EPA-600/3-77-121
October 1977
Ecological Research Series
ENVIRONMENTAL IMPLICATIONS OF TRENDS
IN AGRICULTURE AND SILVICULTURE
Volume I: Trend Identification
and Evaluation
Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Athens, Georgia 30601
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
cies, and materials. Problems are assessed for their long- and short-term influ-
ences. Investigations include formation, transport, and pathway studies to deter-
mine the fate of pollutants and their effects. This work provides the technical basis
for setting standards to minimize undesirable changes in living organisms in the
aquatic, terrestrial, and atmospheric environments.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/3-77-121
October 1977
ENVIRONMENTAL IMPLICATIONS OF TRENDS
IN AGRICULTURE AND SILVICULTURE
Volume I: Trend Identification and Evaluation
by
Dr. Samuel G. Unger
Principal Investigator
Development Planning and Research Associates, Inc.
Manhattan, KS 66502
and
The Tuolumne Corporation
Corte Madera, CA 94925
Contract No. 68-03-2451
Project Officer
Dr. George W. Bailey
Environmental Research Laboratory
Athens, GA 30605
ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
ATHENS, GA 30605
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DISCLAIMER
This report has been reviewed by the Environmental Research Laboratory,
U.S. Environmental Protection Agency, Athens, 6A, and approved for publica-
tion. Approval does not signify that the contents necessarily reflect the
views and policies of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or recom-
mendation for use.
11
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FOREWORD
Environmental protection efforts are increasingly directed towards pre-
venting adverse health and ecological effects associated with specific com-
pounds of natural or human origin. As part of this Laboratory's research on
the occurrence, movement, transformation, impact, and control of environmental
contaminants, management or engineering tools are developed for assessing and
controlling adverse environmental effects of non-irrigated agriculture and of
silviculture.
Agricultural and silvicultural practices, already significant sources of
water and air pollution, represent areas of increasing environmental concern
as these production systems expand to meet growing population needs. This
study assesses the environmental implications and effects of short- and long-
term trends in American agriculture and silviculture and identifies research
needs and policy issues. The developed information should benefit environmen-
tal managers as they attempt to anticipate pollution problems of the future.
David W. Duttweiler
Director
Environmental Research Laboratory
Athens, Georgia
111
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PREFACE
The results of this research study, i.e., "Environmental Implications of
Trends in Agriculture and Silviculture," are presented in two parts:
Volume I: Trend Identification and Evaluation, and Volume II: Environ-
mental Effects of Trends.
Volume I identifies, defines, rates and rank-orders the most important
environmentally-related trends within all major subsectors of agriculture
and silviculture. The environmental ratings and rankings were made by
selected panels of professionals from throughout the nation, given the
Contractor's interim report of trend-by-trend assessments. Over 240 spec-
ific subtrends, representing over 70 trend groupings, were evaluated across
five panel areas, i.e., subsectors of agriculture and silviculture. These
panel areas were: (1) Nonirrigated Crop Production, (2) Irrigated Crop
Production, (3) Feedlot Production, (4) Range and Pasture Management, and
(5) Silviculture and Harvest Management. Separate sections of the Volume I
report are devoted to each of these panel areas of study.
Volume II extends the environmental assessment for major trends from each_
panel area, primarily the crop production subsectors. Ultimately, the main
evaluations of Volume II were assessments of each trend's probable ecological
effects, i.e., aquatic life, terrestrial life and human health impacts.
These evaluations were also completed by professionals in a workshop setting
given the Contractor's background summary of detailed findings for each trend-
subtrend. Volume II also contains an assessment of continuing research needs
and prospective policy issues involving agriculture and silviculture and
environmental quality management.
Throughout the study both short term (1985) and long term (2010) effects
were evaluated, although emphasis was placed on the long term. Further-
more, the study considered beneficial as well as adverse effects of trends
in agriculture and silviculture. The intent was that the nation's environ-
mental quality can perhaps be as readily enhanced through the promotion of
beneficial trends as through the control of adverse trends. Finally, the
research approach of this study relied heavily upon the value judgements
of professionals from agriculture, silviculture and the basic sciences.
This approach was regarded as essential given our current data and knowl-
edge of the environmental effects of agriculture and silviculture. On
balance, we believe that the composite, informed professional judgements
as presented herein are most reflective of the environmental implications
of trends in agriculture and silviculture.
IV
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ABSTRACT
This study determined and assessed those current and emerging trends in U.S.
agriculture and silviculture which will have the most significant environ-
mental implications in the future. Volume I, the first of two volumes, de-
lineates trends and presents a general environmental implications assessment
of trends and developments in all major subsectors of agriculture and silvi-
culture; and Volume II presents a more detailed environmental assessment
of selected major trends, including specifically an assessment of each trend's
ecological effects. The study considered beneficial as well as adverse en-
vironmental implications in the assessment process; and, further, assessed
the environmental implications of trends in both the short term (1985) and
the long term (2010).
Five major subsectors of agriculture and silviculture were included in the
analysis: (1) Nonirrigated Crop Production, (2) Irrigated Crop Production,
(3) Feedlot Production, (4) Range and Pasture Management, (5) Silviculture
and Harvest Management. Within each subsector, numerous trends and develop-
ments were identified and defined by the Contractor. Thereafter, an eval-
uation workshop, comprised of subsector professionals from throughout the
nation, evaluated, rated and rank-ordered the most significant environ-
mentally-related trends both by subsector designation and across subsectors
of agriculture.
A more detailed evaluation was made of selected trends from among the leading
five trends from each panel area in the second part of the study. Namely,
additional research was conducted on the extensiveness of each trend, re-
source use implications, productivity changes and pollutant changes by media.
Additionally, a second workshop emphasizing ecological effects of the major
trends was conducted to ascertain probable aquatic life, terrestrial life
and/or human health impacts associated with these trends.
The study further determined relevant research needs to enhance subsequent
environmental implications assessments in agriculture and silviculture,
and enumerated probable policy issues involving the agriculture and silvi-
culture sectors and environmental quality management. These research needs
and policy issues are also described in Volume II.
This report was submitted in fulfillment of EPA Contract No. 68-03-2451
by Development Planning and Research Associates, Inc., Manhattan, Kansas,
and its subcontractor, The Tuolumne Corporation, Corte Madera, California,
under the sponsorship of the Environmental Protection Agency. Work was
completed as of August, 1977.
v
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CONTENTS
FOREWORD 111
PREFACE 1v
ABSTRACT v
LIST OF EXHIBITS 2L
ABBREVIATIONS xiii
ACKNOWLEDGEMENT xiv
EXECUTIVE SUMMARY xvi
I. INTRODUCTION 1
A. Scope of Study 1
B. Procedures and Assumptions 2
C. Definitions 4
II. ENVIRONMENTAL ISSUES INVOLVING AGRICULTURE AND
SILVICULTURE 5
A. Major Pollutants and Their Sources 5
1. Pesticides 5
2. Nutrients 8
3. Soil Sediment and Heavy Metals 9
4. Salinity 9
5. Other Pollutants and Sources 9
B. Potential Environmental Effects of Pollutants
from Agriculture and Silviculture 11
1. Water Pollution 13
2. Soil Pollution 15
3. Air Pollution 16
4. Potential Environmental Pollution From
Other Agricultural and SiIvicultural
Practices 16
C. Pollution Effects on Silviculture and Agriculture 17
III. A SCENARIO OF THE FUTURE: 1976-2010 18
A. Output Projections 18
B. Resource Availability 20
C. General Assumptions 23
D. Function of Moderate Growth Scenario 28
IV. THE EVALUATION WORKSHOP 30
A. The Evaluation Workshop 30
B. Workshop Procedures 31
C. Participants 36
VI1
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CONTENTS (continued)
V. THE LEADING ENVIRONMENTALLY-RELATED TRENDS: AGRICULTURE
AND SILVICULTURE 38
VI. ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVI-
CULTURAL TRENDS: PANEL 1 - NONIRRIGATED CROP PRODUCTION 41
A. Major Trend Rankings and Practices Assessments 41
B. Environmental Implications of Major Trends and
Practices 45
C. Background Summary 49
1. Overview and Base Data 49
2. Trends and Environmental Implications 56
VII. ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVI-
CULTURAL TRENDS: PANEL 2 - IRRIGATED CROP PRODUCTION 74
A. Major Trend Rankings and Practices Assessments 74
B. Environmental Implications of Major Trends and
Practices 78
C. Background Summary 81
1. Overview and Base Data 81
2. Trends and Environmental Implications 89
VIII. ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVI-
CULTURAL TRENDS: PANEL 3 - FEEDLOT PRODUCTION 107
A. Major Trend Rankings and Practices Assessments 110
B. Environmental Implications of Major Trends and
Practices 112
C. Background Summary 115
1. Overview and Base Data 116
2. Trends and Environmental Implications 124
IX. ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVI-
CULTURAL TRENDS: PANEL 4 - RANGE AND PASTURE MANAGEMENT 135
A. Major Trend Rankings and Practices Assessments 135
B. Environmental Implications of Major Trends and
Practices 136
C. Background Summary 141
1. Overview and Base Data 141
2. Trends and Environmental Implications 144
X. ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVI-
CULTURAL TRENDS: PANEL 5 - SILVICULTURE AND HARVEST
MANAGEMENT 156
A. Major Trend Rankings and Practices Assessments 157
B. Environmental Implications of Major Trends and
Practices 161
C. Background Summary 163
1. Overview and Base Data 163
2. Trends and Environmental Implications 167
van
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CONTENTS (continued)
XI. WORKSHOP RANKING OF MAJOR TRENDS ACROSS PANELS 175
XII. CONCLUSIONS AND RECOMMENDATIONS 180
A. Conclusions 180
B. Recommendations 181
XIII. BIBLIOGRAPHY
APPENDIX A - THE EVALUATION WORKSHOP: PURPOSE AND PROCEDURES A-l
APPENDIX B - THE EVALUATION WORKSHOPS DETAILED PANEL RATINGS A-17
IX
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LIST OF EXHIBITS
Number Page
1 Summary of each panel's ranking and adjusted ratings
(AR) of major environmentally-related trends in
agriculture and silviculture xviii
2 Summary of workshop rankings of major trends in agri-
culture and silviculture xix
II-l Major pollutants from agriculture and silviculture 6
II-2 Representative rates of erosion from various land uses 10
11-3 Relative erosion from various land uses: Nationwide 10
II-4 A flow diagram of sources of environmental pollution
and their implications 12
III-l Exogenous variables: Projections under moderate growth
assumptions on population, per capita personal income,
housing starts, and gross national product with current
environmental controls 19
III-2 Exogenous variables: Graphical representation under
moderate rates of growth 19
III-3 Projections by commodity for selected years 1985 and
2010 under moderate growth assumptions 21
III-4 Projections index for agricultural resources for selected
years 1985 and 2010 under moderate growth assumptions 22
111-5 Agricultural resources: Projections under moderate
growth assumptions 22
III-6 Distribution of U.S. land by use category (estimated
acres) 1975 24
111-7 Potential for Copland with development necessary by
land uses (estimated acres) 1975 25
111-8 Sources of "potential cropland" by current use (esti-
mated acres) 1975 26
IV-1 Environmental implications of trends in agriculture
and silviculture 32
IV-2 Rating system definition for the assessment of environ-
ment implications of trends in agriculture and
silviculture 35
V-l Summary of panel and workshop rankings of major trends
in agriculture and silviculture, 1976-2010 39
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LIST OF EXHIBITS (Continued)
Number Page
VI-1 Ranking of environmentally-related trends, 1976-2010:
Nonirrigated Crop Production 42
VI-2 Description of major environmentally-related trends,
1976-2010: Nonirrigated Crop Production 43
VI-3 Environmental ratings of top ten trends and associated
practices: Nonirrigated Production 44
VI-4 Nonirrigated cropland as a percent of total cropland
harvested: 1969 49
VI-5 Relative potential contribution of cropland to watershed
sediment yields 51
VI-6 Location of cropland - corn, soybeans, cotton, wheat 53
VI-7 Acres receiving fertilizer and average fertilizer rates
of four crops in the United States, 1974 54
VI-8 Croplands treated with pesticides and herbicides: 1969 55
VI-9 Crop production system: Nonirrigated Cropland 57
VI-10 Environmentally-related trends: Nonirrigated Cropland 58
VI-11 Description of environmentally-related trends and
developments: Nonirrigated Cropland 61
VI-12 Environmentally-related trends: Nonirrigated Cropland 65
VII-1 Ranking of environmentally-related trends, 1976-2010:
Irrigated Crop Production 75
VII-2 Description of major environmentally-related trends,
1976-2010: Irrigated Crop Production 76
VI1-3 Environmental ratings of top ten trends and associated
practices: Irrigated Crop Production 77
VI1-4 Irrigated cropland harvested as a percent of total
cropland harvested: 1969 82
VII-5 Irrigated cropland in specified crops and pasture on
farms: 1969 83
VII-6 Irrigated cropland receiving high rates of fertilization 85
VII-7 Concentrations of feedlots which include dairy farms,
beef, hogs, and chickens 87
VII-8 Croplands treated with pesticides and herbicides: 1969 88
VII-9 Crop production system: Irrigated Cropland 90
VII-10 Environmentally-related agricultural trends: Irrigated
Cropland 91
VII-11 Description of environmentally-related trends and
developments: Irrigated Cropland Production 94
VII-12 Environmentally-related trends: Irrigated Cropland 98
VIII-1 Ranking of environmentally-related trends, 1976-2010:
Feedlot Production 108
VIII-2 Descriptions of major environmentally-related trends,
1976-2010: Feedlot Production 109
XI
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LIST OF EXHIBITS (Continued)
Number
VIII-3 Environmental ratings of ten trends and associated
practices: Feedlot Production
VIII-4 Cattle fattened on grain and sold for slaughter. Each
dot represents 5,000 head
VIII-5 Milk cows. Each dot represents 1,000 milk cows
VIII-6 Hogs and pigs. Each dot represents 10,000 hogs Tjg
VIII-7 Broilers and other meat-type chickens. Each dot
represents 500,000 chickens 120
VIII-8 Chickens 3 months old or older. Each dot represents
50,000 chickens 121
VIII-9 Livestock production projections ]25
VIII-10 Livestock production system (feedlots) 126
VIII-11 Environmentally-related trends in agriculture: Feedlot
production 127
VIII-12 Description of environmentally-related trends and
developments: Feedlot Production 129
VIII-13 Overall trends in feedlot concentrations 132
IX-1 Ranking of environmentally-related trends, 1976-2010:
Range and Pasture Management 136
IX-2 Description of major environmentally-related trends,
1976-2010: Range and Pasture Management 137
IX-3 Environmental ratings of top ten trends and associated
practices: Range and Pasture Management 138
IX-4 Range and pasture systems 145
IX-5 Environmentally-related trends: Range and Pasture 145
IX-6 Description of environmentally-related trends and
developments in range and pasture 148
IX-7 Environmentally-related trends: Ranges and Pastures 151
X-l Ranking of environmentally-related trends, 1976-2010:
Silviculture and Harvest Management 157
X-2 Description of major environmentally-related trends,
1976-2010: Silviculture and Harvest Management 158
X-3 Environmental implications of all silviculture trends,
regional and national, 1976-2010 159
X-4 Environmental rating of top ten trends and associated
practices: Silviculture and Harvest Management 160
X-5 Summary of softwood timber demands projected to 2020 164
X-6 Summary of hardwood timber demands projected to 2020 165
X-7 Silvicultural production system 168
X-8 Environmentally-related trends: Silviculture 169
X-9 Description of trends and developments: Silviculture
and Harvest Management 171
XI1
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LIST OF EXHIBITS (Continued)
Number Page
XI-1 Summary of workshop rankings of major trends in
agriculture and silviculture 176
XI-2 Panel's ranking of their top five trends within
twenty major trends 178
A-l Rating system definition for the assessment of environ-
ment implications of trends in agriculture and silvi-
culture A-3
B-l Summary of all panel's rankings of twenty major trends A-19
B-2 Summary of Individual participant's ranking of twenty
major agriculture trends A-20
B-3 Summary of individual participant's integration of
second five trends (#6-#10), as identified by his
panel, into major twenty trends A-21
ABBREVIATIONS
The following abbreviations were used in the text of this research study.
DDE - 1,1-dichloro - 2,2-bis (p-chlorophenyl) ethylene
DDT - 1,1,1 trichloro - 2,2 bis (p-chlorophenyl) ethane
DDTR - a compilation of all members of the DDT group
ERS - Economic Research Service
FAO-WHO - Foreign Agriculture Organization-World Health Organization
mg - milligram, .001 gram
OBERS - Bureau of Economic Analysis (formerly Office of Business
Economics), U.S. Department of Commerce, and Economic
Research Service, U.S. Department of Agriculture
ppb - parts per billion
ppm - parts per million
ppt - parts per trillion
ug - microgram, .000001 gram
Xlll
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ACKNOWLEDGEMENT
Many individuals and work groups participated in this research study. In
particular, Dr. George W. Bailey, Environmental Research Laboratory, EPA,
Athens, Georgia guided the study as Project Officer. Thomas E. Waddell,
Office of Research and Development, EPA, Washington, D. C. assisted with
the coordination of research efforts and provided liaison support.
Special thanks goes to Richard L. Duesterhaus and Glen H. Loomis, Office
of Environmental Quality Activities, U. S. Department of Agriculture (USDA)
and the associated interagency (USDA-EPA-Uniyersity) Ad Hoc Subcommittee
on the Environmental Implications of Trends in Agriculture and Silviculture.
This work group reviewed the study's plan of work, made constructive com-
ments, and subsequently recommended participants for the Evaluation Work-
shop that reviewed the Contractor's initial work. These recommendations
included professionals of many disciplines from USDA, the universities,
and the private sector who are located throughout the nation. All phases
of agriculture and silviculture were considered via the assistance of this
Subcommittee and its affiliation with the Office of the Secretary, U. S.
Department of Agriculture.
Particularly important to this study, also, were the individual and combined
efforts of the evaluation workshop participants (both in the Volume I and
Volume II portions of study) who assessed the environmentally-related trends
in agriculture and silviculture, 1976-2010. These participants, as briefly
named below by panel area, are identified further within the report. DPRA
sincerely acknowledges their contributions.
Nonirrigated Crop Production
George M.
William L
Pierre L.
Velmar W.
Victor J.
Ralph L.
Browning,
Colville
Crosson
Davis
Kilmer
Leonard
Ch.
. Gary Margheim
. Walt H. Wischmeier
Irrigated Crop Production
. Roy S. Rauschkalb, Ch.
. Charles M. Hohn
. Gerald L. Homer
. R. Eugene Merrill
Range and Pasture Management
. Glen D. Fulcher, Ch.
. John L. Launchbaugh
. James M. Scholl
. John Studeman
Silviculture and Harvest Management
. Noel Larson, Ch.
. George Dissmeyer
. Warren C. Harper
. Stanley J. Ursic
. David D. Wooldridge
xiv
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Feedlot Production Agriculture-Ecology Panel
. Raymond C. Loehr, Ch. . Lloyd C. Hulbert
. Daniel D. Badger . H. Page Nicholson
. D. Eugene Becker . Fred W. Oehme
. Bartley P. Cardon . Walt H. Wischmeier
. James K. Koelliker . John L. Zimmerman
Within DPRA and the Tuolumne Corporation, many professional staff and
consultants assisted with the preparation of this report: Dr. Raymond
E. Seltzer, Arthur C. Barker, Dr. Gary A. Davis, Dr. S. McCallum King,
AT H. Ringleb, and Rita D. Walter contributed importantly. From the
Tuolumne Corporation, the principal contributors were Peter Arnold,
James L. Zeigler, and Dr. F. Bruce Lamb.
Samuel G. Unger
Principal Investigator
xv
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EXECUTIVE SUMMARY
This study for the Environmental Protection Agency determined and assessed
those current and emerging trends in U.S. agriculture and silviculture
which will have the most significant environmental implications -- either
beneficial or adverse. This Volume I report, the first of two volumes,
presents a general assessment of numerous trends and developments in all
major subsectors of agriculture and silviculture. Volume II presents a
detailed assessment of selected major trends and their expected environ-
mental effects.
A. Purpose and Scope of Study
The primary objectives of the overall study were:
(1) to assess the environmental implications of both short-term
(1985) and long-term (2010) trends in American agriculture
and silviculture, and
(2) to identify pertinent environmental issues, associated re-
search needs, and policy issues.
Two phases of research were involved in the study:
(1) Phase I, the subject of this report, determined on a priority
basis the major environmentally-related trends in agriculture
and silviculture, and
(2) Phase II, assessed the environmental impacts of selected key-
trends (i.e., quantified, where possible, their environmental
effects) and identified research needs and policy issues.
B. Research Procedures
Phase I of the study was designed (1) to identify germane major pollu-
tants stemming from agricultural and silvicultural practices and to
describe their potential beneficial or adverse environmental effects,
(2) to prepare from acceptable and documented ERS and OBERS data a
moderate-economic-growth projection reflective of short-term (1985)
and long-term (2010) agricultural and silvicultural product demands,
and (3) to identify current and potential agricultural and silvi-
cultural practices which impinge upon environmental concerns. Upon
xvi
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the basis of these three steps, a preliminary report of findings was
prepared which served as a basis for a workshop evaluation conducted
by representatives of Development Planning and Research Associates,
Inc., Environmental Protection Agency, and the Tuolumne Corporation,
a subcontractor to DPRA which assisted in preparing the silviculture
part of this study.
The Evaluation Workshop brought together, in addition to EPA and Contractor
representatives, twenty-six participants from throughout the U.S. and from
a complex variety of appropriate scientific and technological disciplines.
The group was divided into panels reflecting the agricultural and silvi-
cultural sectors considered in the report, namely:
1. Nonirrigated Crop Production
2. Irrigated Crop Production
3. Feedlot Livestock Production
4. Range and Pasture Management
5. Silviculture and Harvest Management
Taking as their data base the preliminary report prepared by DPRA, the
participants modified that data where necessary and (a) identified the
key agricultural and siIvicultural trends by panel area, (b) assessed
the environmental effects of their composite practices, (c) assigned
environmental ratings to each trend, and (d) ranked, in the order of
their importance, the leading twenty agricultural and leading five
siIvicultural trends.
Following the Evaluation Workshop, DPRA assessed the workshop's findings
and prepared the present report.
C. Organization of Report
This Volume I report organizes the findings of the Phase I study as
follows:
Section I: discusses the major components of the study and
briefly describes its procedures and assumptions,
Section II: surveys germane biological and chemical pollution
data and discusses the affect of such pollutants
on air, water, and land eco-systems,
Section III: presents and discusses the economic growth model
data pertinent to agriculture and silviculture re-
sources and demands,
Section IV: describes the Evaluation Workshop and its procedures,
Section V: presents, as an overview previous to further dis-
cussion in succeeding sections, the rankings of the
leading trends in each sector considered in the report.
xvn
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Sections VI-X: presents for each panel area (a) the major trend
rankings and their composite practices assess-
ments, (b) the environmental implications of those
trends and practices, and (c) the preliminary over-
view base data descriptive of the major trends and
practices,
Section XI: presents the Evaluation Workshop's integrated
rankings of the leading twenty agricultural and
leading five silviculture! trends,
Section XII presents this report's conclusions and recommenda-
tions, and the
Appendices: presents additional workshop procedural details
and supplemental workshop trend rankings.
D. Results of the Study
1. Rankings of Panel Trends
The major results of this study are the rankings of the five most environ-
mentally-related trends in each of the agricultural and silvicultural sub-
sectors in the study.
Each of the Evaluation Workshop panels delineated, assessed, rated and,
finally, rank-ordered the major environmentally-related trends (and
probable developments) in its subject area, i.e., Nonirrigated Crops..
Irrigated Crops, Feedlot Production, Range and Pasture Management, and
Silviculture and Harvest Management. A summary of each of the panel's
leading trends is shown in Exhibit 1.
The trends shown are only part of the findings by each panel. The re-
maining trends (a total of 71) and also subtrends (a total of 241) are
described in detail in the text. However, the twenty-five trends as
listed in Exhibit 1 adequately illustate the range and diversity of
environmentally-related trends which occur in the agriculture and silvi-
culture sectors of the economy. Associated environmental problems are,
consequently, diverse and potentially complex.
Also shown in Exhibit 1 are the panel's "adjusted rating" scores which
reflect the relative environmental importance—based upon the panel's
judgements—of each of the leading trends (a maximum absolute score of
25 was permitted). However, caution is advised in making comparisons
across panels since each panel independently applied the rating system
of the workshop.
Next, and in accordance with the workshop procedures, the leading five
trends from each panel were submitted to the general workshop for further
evaluation and overall ranking.
XVlll
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Exhibit 1. Summary of each panel's ranking and adjusted ratings (AR) of major environmentally-related trends
in agriculture and silviculture
X
Trend
Panel No. I/ Trend
1.
Nom'rrigated Crop (104) Runoff & Erosion Control
Production (119) Improvement of Seeds & Plants (103 4 114)
(101; Conservation Tillage
(120) Scouting & Integrated Controls (112 + 117)
Initial Panel
Rank of Top
Five Trends
1
2
3
4
Panel Adjusted
Rating (AR)
18
16
14
13
(121) Developing New Biological and Chemical
2.
Pesticides (115 + 116)
Irrigated Crop (208) Improving Water Application
Production (204) Runoff & Erosion Control
(211) Methods of Nutrient Application
(220) Developing Integrated Controls
(210) Using Plant 4 Soil Analysis
3.
Feedlot Production (308) Feedlot Size
(319) Feedlot Design for Waste Management (306 + 311 + 312)
(317) Residual Disposal (312 + 315)
(313) Odor Control
(318) Feed Efficiency & Ration (302 + 305)
4.
Range & Pasture (406) Grazing Practices: Range & Pasture
Management (405) Stocking Ranges
(401) Range & Pasture Renovation
(416) Using Increased Resources (411 + 415)
(417) Range & Pasture Improvement (402 + 404 + 407)
5.
Silviculture and (502) Access to Timber Resource (Woods)
Harvest Management
505) Site Preparation
503) Log Extraction
504) Utilization (Logs & Residues)
510) Fire Control
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
12
22
18
15
12
9
15
12
10
9
8
8
7
6
5
5
4
4
3
2
2
The trend number denotes both the panel designation (first digit) and the sequence number (third and fourth digits) within each
panel area. Also, the Workshop participants combined and/or redefined selected trends as Indicated in the trend description If
appropriate. These numbers are used throughout this report for reference purposes.
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Exhibit 2. Summary of workshop rankings of major trends in
agriculture and silviculture
Trend
No.
(104)
(101)
(208)
(204)
(119)
(120)
(121)
(319)
(308)
(317)
(211)
(406)
(405)
(220)
(401)
(210)
(313)
(416)
(318)
(417)
(502)
(505)
(503)
(504)
(510)
Agriculture Trends
Runoff and Erosion Control (Nonirrigated)
Conservation Tillage
Improved Water Application
Runoff and Erosion Control (Irrigated)
Improvement of Seed and Plants
Scouting and Integrated Controls
Developing New Biological and Chemical
Pesticides
Feedlot Design for Waste Management
Feedlot Size
Feedlot Residual Disposal
Method of Nutrient Application
Grazing Practices: Range & Pasture
Stocking Rates: Range & Pasture
Developing Integrated Controls
Range & Pasture Renovation
Using Plant & Soil Analysis
Odor Control
Using Increased Resources: Range & Pasture
Feed Efficiency and Rations
Range and Pasture Improvement
Silviculture Trends
Access to Timber Resource
Site Preparation
Log Extraction
Utilization (Logs & Residues)
Fire Control
Workshop
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Rank by Panel 5 -f
1
2
3
4
5
If Silviculture trends were rated separately by Silviculture Panel 5 and
are not included in overall workshop rankings.
-------
2. Rankings of Major Trends
With the understanding that only the most significant five trends from
each panel were to be further assessed and ranked, the workshop concluded
that the major trends of agriculture and of silviculture should be ranked
as shown in Exhibit 2. The agriculture trends were purposefully separated
from the silviculture trends.
Within agriculture, the trends occurring in Nonirrigated Crop Production
tend to be ranked relatively high. Some trends in Irrigated Crop Production
are relatively important and are followed by key Feedlot Production trends.
Range and Pasture Management trends are generally ranked in the lower half
of the leading agriculture trends (two trends, however ranked near the mid-
range of the rankings).
The silviculture sector's leading five trends are shown separately. While
the original workshop procedures requested a joint-ranking of agriculture
and silviculture trends, a judgement was made to separate the two sectors.
This decision was reached after deliberations both by the workshop as a
whole and, especially, by the Silviculture Panel. In part, the separation
reflects the Silviculture Panel's reluctance to rank the agriculture panels'
trends, and vice versa. Also, however, a genuine concern exists in com-
paring (without more quantified environmental data) the environmental impli-
cations of largely different production sectors (e.g., forestry produces
on a 30 to 60 year or more growth cycle; agriculture produces intensely
on basically an annual growth cycle). In addition, silviculture is rela-
tively more concerned with environmental factors such as ecological dis-
ruptions, wildlife habitat and aesthetics than is agriculture. On balance,
however, a general observation of the workshop was that silviculture trends
would tend to be ranked in the lower half of the trends shown when such
ranking considers basic soil, water and air media effects only.
A further observation of the workshop was that the major trends shown
in Exhibit 2 would include some secondary trends (such as trends 6 to 10
of Nonirrigated Crop Production) if these trends had been included in the
ranking procedure. Again, this limitation must be assessed independently—
which is done in the text of this summary report.
E. Directions for Future Study
The objectives of this Phase I report were realized—the major environ-
mentally related trends of agriculture and silviculture were evaluated
and ranked—under a rather strict set of guidelines and within a limited
scope of study. As a byproduct of the workshop, Development Planning
and Research Associates recommended that additional attention be focused
on the following factors in future efforts to assess the environmental
implications of trends in agriculture and silviculture.
xxi
-------
1. Regionalization of Trends. Regional variations in the significance
of specific trends should be assessed.
2. Segmentation of Panel Areas. Further segmentation of a panel area
is warranted. For example, species categorization for Livestock
and the separation of ranges and pastures in Range and Pasture Manage-
ment would provide additional important results.
3. Additional Trends. The trend coverage of the workshop was comprehen-
sive but not exhaustive. Some panelists voiced concern for potential
but as yet not fully realized research that may significantly affect
agriculture and silviculture production. Their assessments would
complement this report.
4. Quantified Environmental Data. Few empirical data exist for
quantitative national assessments of expected environmental effects.
The Workshop was primarily founded on the principal that informed
value judgements were our best resource for the evaluations. An
improved quantitative data base is highly desirable.
5. Public and Private Support of Trends. The Workshop was generally
optimistic about the continuation of public and private support of
sound, realizable environmentally-related policies and programs,
e.g., soil conservation, improved management systems, farm policies,
etc. However, further study is warranted of the infrastructures
that are necessary to maintain viable, environmentally respon-
sible agriculture and silviculture sectors of the U. S. econ-
omy.
6. Rating System Improvements. The rating system utilized by the work-
shop was effective as implemented by each panel. However, refine-
ments might be made to facilitate the use of rating scores across
panel areas.
7. Time Frame. The Workshop was constrained by time to focus principally
on the long-term future, i.e., 2010. Further assessments of the short-
term future were recognized as important, especially since some environ-
mental effects could worsen in the near future prior to the adoption
by the majority of the farmers and foresters of improved management
practices which will eventually provide beneficial environmental
effects relative to current practices.
In conclusion, Development Planning and Research Associates regards the
identification and ranking of the leading trends in each panel area as
the principal results of the Evaluation Workshop. Secondly, the overall
rankings across panels in agriculture, and separately for silviculture,
are informative and helpful in the aggregate; however, from the stand-
point of balanced environmental policies and programs, each panel area
represents a major, diverse segment of the economy which will require
focused attention and management resources if future environmental im-
provements are to be realized.
xxn
-------
SECTION I
INTRODUCTION
Agricultural and silvicultural management systems in the United States
contribute to environmental pollution. Although these pollutants
(residuals of the production systems) are dispersed throughout the
nation, their environmental implications are consequential both in
the aggregate and where local-regional concentrations of pollutants
occur.
Nationally, the agricultural and silvicultural sectors of the economy
are important sources of water, air and soil pollutants. They are
jointly the largest source of suspended solids (e.g., sediment, nutrients)
and biological pollutants (e.g., cropland, feedlot, grassland and forest
residues) in surface waters. On the local-regional level, specific en-
vironmental damages have at times been traced to the detrimental impacts
of agriculture-silviculture residuals, £e_r se_. Also, air (e.g., dust,
smoke, odor) and soil (e.g., salinity) pollution problems are potentially
serious on a local-regional basis.
As the agricultural and silvicultural sectors continue to increase output
through both intensive and extensive management practices, even greater
aggregate levels of residuals and/or local-regional concentrations may
occur; therefore, an assessment of the environmental aspects of critical
trends within these sectors of the economy is warranted.
A. Scope of Study
This study for the Environmental Protection Agency sought to determine
those current and emerging trends in U.S. agriculture and silviculture
which will have the most significant environmental implications—either
beneficial or adverse. The primary objectives of the study were:
(1) to assess the environmental implications and impacts of
both short-term (1985) and long-term (2010) trends in
American agriculture and silviculture, and
(2) to identify pertinent environmental issues, associated
research needs and policy issues.
Two phases of work were involved in the overall study:
-------
Phase I, the subject of this Volume I report, determined on a
priority basis the major environmentally-related trends in agri-
culture and silviculture, and
Phase II, the subject of the Volume II report, assessed the
environmental impacts of selected key trends (i.e., quantified
their effects where possible) and will identify research needs
and policy issues.
Included within Phase I was a workshop conference of selected agri-
cultural and forestry experts. This conference group assisted the
Contractor in determining those trends of major significance and
helped assess their related environmental implications.
B. Procedures and Assumptions
Prior to the workshop evaluation, the Contractor prepared a background
summary report, primarily a reference document which served as the data
basis for the workshop conference of agricultural and silvicultural ex-
perts. The report categorized and enumerated the principal environ-
mentally related trends and developments within agriculture and silvi-
culture as identified by the Contractor. The workshop participants
were asked to further judge the significance of these trends and de-
velopments according to procedures as setforth herein. Where necessary,
the workshop participants were advised to modify the Contractor's pre-
liminary data and assumptions.
The evaluation workshop group was divided into five panels to cover
various aspects of agriculture and silviculture as follows:
Agriculture
. Nonirrigated Crop Production
. Irrigated Crop Production
. Feedlot Livestock Production
. Range and Pasture Management
Silviculture
. Silviculture and Harvest Management
Workshop participants participated in their respective panels and in
general sessions in order both to identify major trends within their
major areas of expertise and to assess the overall relative importance
of all major trends across the five panel areas. The detailed proce-
dures and workshop agenda are described further in the Appendix of
this report.
-------
Using the Contractor's preliminary data base as a guide, the workshop
panelists reviewed the identified trends for validity and complete-
ness and rated the key environmentally-related trends in agriculture
and silviculture. The results of the workshop, as summarized herein,
served as principal input into Phase II over the overall study.
The framework of study required that trends and developments in agri-
cultural and silvicultural production be assessed for the period 1976-
2010. Obviously, many alternative production projections could reason-
ably be given based upon differing assumptions as to population growth
rates (domestic and world), economic growth rates (e.g., gross national
product), the levels of technological developments, the levels of foreign
trade, and alternative governmental policies affecting energy, environ-
ment, employment, etc. The study to be uniformly consistent utilized
one selected "scenario" of production which reflects moderate growth in
agriculture and silviculture.
The selected source for the future projections of agriculture and silvi-
culture was the OBERS Projections of the Water Resources Council as pre-
pared by the U. S. Department of Commerce and the U.S. Department of Agri-
culture. In addition, the contractor used data supplemental to this pro-
jection as published by the Economic Research Service of the U. S. Depart-
ment of Agriculture in its current publication "Agriculture, The Third
Century."
The rationale for choosing a specific scenario projection is that the
present study, with its limited scope, was to emphasize the assessment
of the environmental implications for one level of economic development
rather than assess the implications of alternative futures. To be sure,
the trends and developments in agriculture and silviculture would be quan-
titatively impacted by changes in the baseline scenario; however, the basic
environmental implications of such trends would not be largely altered.
(Note: the most demanding impact of agriculture on the environment would
result if foreign trade (export demand) were assumed high enough to require
the utilization of significantly more new cropland acreage. Unless such
does happen, the trends and developments are likely to continue as des-
cribed herein.)
A scenario of the future—1976-2010— is described in section III, below.
For comparison, alternative agricultural output levels which are about
20 percent higher to about 10 percent lower in 2010 than the baseline
projection of this study have been projected. This range of aggregate
output levels suggests the degree of future variability that may be con-
templated. Again, however, this study sought to identify and assess those
trends in agriculture and silviculture which are expected in association
with the baseline scenario case. The emphasis is on those trends which
are deemed to have the most significant environmental implications—either
beneficial or adverse.
-------
C. Definitions
Agriculture will refer only to those activities directly involved with
farming, including crop production (nom'rrigated and irrigated), live-
stock production, and range and pasture management. Agribusiness acti-
vities such as processing, distribution and farm supply are not included.
Other agriculture-related activites, e.g., strip mine reclamation and
wetlands management, were also excluded from the study. Trends and de-
velopments in these areas are clearly of concern to the Environmental
Protection Agency, but these remaining areas were not included in this
study's scope of work.
Silviculture will refer to both forest production and harvest management
in this study. Silviculture commonly refers to the establishment, com-
position, constitution and growth of forests. The harvesting of forest
products, including area access and logging are incorporated herein as
an integral part of overall forest management.
For both agriculture and silviculture, the primary focus will be toward
those trends and developments which occur or are implemented on-site,
i.e., at the farming or producing location. Off-site activities, such
as food processing or lumber milling are not included in the study.
-------
SECTION II
ENVIRONMENTAL ISSUES INVOLVING AGRICULTURE AND SILVICULTURE
Besides their most recognized and generally useful outputs, agricultural
and silvicultural systems also produce residuals which affect various
environmental media, including:
. surface water (quality and supply)
. groundwater (quality and level)
. air (quality)
. soil (composition)
The presence of such residuals does not necessarily represent an en-
vironmental hazard, for most ecosystems have natural sources of re-
siduals (sediment, nutrients, etc.) which are utilized in food chains;
however, if toxic substances or excessive quantities of residuals are
discharged into ecosystems, the subsequent uses of these environments
are detrimentally affected.
A. Major Pollutants and Their Sources
Major pollutants from agriculture and silviculture activities include
sediment, plant nutrients, heavy metals, salts, biodegradable organics,
pesticides, pathogens, odors, and fugitive dusts. These residues, plus
others, stem from the various sources summarized in Exhibit II-l. A
discussion of these pollutants and their effects follows.
1. Pesticides
Pesticide residues are pollutants from irrigated and non-irrigated crop-
lands, from silviculture practices, and occasionally from range and
pasture lands. Cropland pesticides constitute the largest source of
these residues; smaller amounts are contributed by silviculture, range,
and pasture land managements. The residues contaminate surface water,
ground water, soil, the earth's atmosphere, and the human food chain.
Water loading. Pesticides reach water through direct surface run-off
(pollutants dissolved in solution and bound on sediment), ground water
seepage, aerial drift during application, and by being redeposited in
waters upon volatilization. The literature on pesticide levels in U.S.
waters and in surface run-off exhibits a wide variety of results reflecting
-------
regional differences in pesticide usage, different experimental techniques,
and assay methods. The percentage of the total applied pesticide which
appears in surface run-off ranges from 0.05 percent trifluralin, 0.12
percent durion (Williss, 75), 2-4 percent chloro-s-triazines (Hall,
72 74: White, 67) to as much as 7.01 percent dichlobenzil and 11.4 percent
atrazine (Bailey, 74). (The higher percentages for atrazine and dichlobenzil
Exhibit II-l. Major pollutants from agriculture
and silviculture
Pollutant
Source
Biodegradable
N P Salts Organics
Sedi-
ment
Pesti-
cides
Micro-
organisms
Crop Production
Small Grains XX X
Row Crops XX X
Hay and Forage XX X
Fruits XX X
Vegetables X X X
Pasture and Rangeland X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Livestock Production
Dairy
Beef
Pasture
Confinement
Hogs
Poultry
Sheep
Idle Land
Farm Woodland
Silviculture
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Source: A. Aleti, and others, "Methods for Identifying and Evaluating the
Nature and Extent of Non-point Sources of Pollutants from Agri-
culture." In: Processing and Management of Agricultural Waste.
Proceeding of the 1974 Cornell Agricultural Waste Management Con-
ference, 1974.
-------
resulted from a simulated hundred-year storm frequency within one hour
of pesticide application. Under typical conditions, less than 5 percent
of the applied pesticides are estimated to enter surface water from
run-off (USDA-EPA, 75)).
Surface run-off pesticide concentrations depend upon the pesticide
solubility, soil type, application techniques, quantity applied, and the
amount and timing of rainfall. (Guenzi, 74; McElroy, 76)
Pesticide residue levels in U.S. waters vary from non-detectable
amounts to 1,000 ppt for DDT (Edwards, 73; Hoi den, 75). Analyses show
that few rivers exceed 10 ppt DDT or 5 ppt DDE. Residue levels of other
pesticides were lower, usually below detection limits. Reported pes-
ticide levels in city water supplies have been minor.
Soil residues. Soil residues of pesticides have been documented by both
the U.S. Soils Monitoring Service and individual investigators. The soil
residue levels range from non-detectable limits to highs of 107.45 ppm
arsenic (presumably, though not necessarily, from non-agricultural sources),
78.4 ppm DDTR, and 35.92 ppm of p.p. DDT (Wiersma, 71, 72). The most
widely spread residue was dieldrin, occurring in 30 percent of the tested
sites. DDTR had the highest mean level of 0.31 ppm in cropland soil.
Most other pesticide mean residue levels ranged from less than 0.01 ppm
to 0.06 ppm. On occasion, soils from non-agricultured areas were shown
to contain pesticide residues.
The persistence of soil residue pesticides depends upon their chemical
properties. DDT, DDTR, and dieldrin are organochlorine pesticides,
are considered persistent,and are found in their active form in the soil
from 3-5 years after application. Phosphate insecticides, such as
parathion and diazion, are non-persistent and usually disappear within 1 -
3 months. Other pesticides, including herbicides, persist from a few weeks
to 18 months.
Atmospheric contamination. Pesticides enter the air through aerial drift
upon application and volatilization following application. Residue
levels in the atmosphere range from 0.0003 ppt-0.158 ppm (Edwards, 73)
with a mean value of 0.001 ppb - 0.002 ppt. They have been found world-
wide in the atmosphere.
Some investigators believe volatilization is the chief source of the pes-
ticide residues in the atmosphere.. Woodwell (71) estimates that as much
as 50 percent of applied DDT ends up in the atmosphere; however, other
investigators find this value to be high (Edwards, 73). Volitilization
may result in 2.9 percent of the applied dieldrin ending up in the atmos-
phere. Large losses of pesticides to the air result from aerial drift
during application. Under adverse weather conditions, 50 percent of aerial
applied pesticides may never reach the target area (Edwards, 73; Spencer, 75)
-------
Food residues. Food in the human food chain receives pesticide residues
from direct uptake by crops, and from the tissues of birds, fish and other
animals. Fish tissue concentrates can be 100 times the water level of
pesticides (Edwards, 73). While some animal tissue tested does exceed
recommended safety limits for pesticide residue levels, they are usually
within these limits. Food crop pesticide residues are well within the
limits set up by FAO-WHO; the highest levels found are only 10 percent
of the safety 1imit.
2. Nutrients
Agricultural and silvicultural residues of nitrogen and phosphorus enter
surface and ground waters from run-off and leaching losses associated
with animal wastes and from movement of sediments into surface waters.
Estimates of total nitrogen contributed to the nation's waters varies
from 1,500 to 15,000 million pounds per year from rural agricultural
land, and 400 to 1,900 million pounds per year from rural non-agricultural
lands. The total phosphorus loading in U.S. waters is estimated at
120 to 1,200 million pounds per year from rural agricultural land and 150 -
750 million pounds per year from rural non-agricultural lands (Dornbush, 74).
The total amounts of nitrogen and phosphorus lost to pollution are dependent
upon a number of variables. For cropland, these include application rates,
soil properties, terrain, soil erosion tendencies, crop management prac-
tices, and rainfall amounts. Many experiments have determined the amount
of nitrogen and phosphorus lost to waters in individual agricultural situ-
ations. The estimates of total applied nitrogen which reach surface waters
vary from 15-54 percent (EPA, 73; NAS, 72). Ranges of total applied
nutrients lost to surface waters are 0.03 - 8.4 pounds per acre for nitro-
gen and 0.01 to 0.80 pounds per acre for phosphorus (Dornbush, 74). Prac-
tices which reduce run-off and soil erosion will tend to reduce nutrient
losses to streams. (Caution: The loading and concentration values of
pollutants per event are generally of more environmental significance
than annual runoff values—absolute or percentage.)
Leaching and run-off losses of nutrients from undisturbed forest areas
and range lands are usually small, but increasing fertilization practices,
clear cutting, and high stocking rates tend to increase the nutrient trans-
port from these sectors. In one selected case of forest fertilization,
nitrogen run-off increased from 0.48 pounds per acre to 0.62 pounds per acre
for urea fertilizer and to 0.92 pounds per acre for ammonium sulfate
fertilizers (Cole, 65). Experimental clear cutting under conditions
dissimilar to those used in silvicultural practices increased nitrogen
loading from 1.78 pounds per acre to more than 53.5 pounds per acre per
year (Bormann, 68). These selected studies are but representative of the
type of increases that can occur, and they are not national figures or
averages. An increased loss of nutrients occurs from range and pasture
land without adequate cover to protect surface soil against erosion.
-------
Run-off and leaching losses of nutrients from animal wastes in housing
and productive units occur, but the extent of this loss varies by geo-
graphic area, size and type of animal unit, and type of waste disposal
system used. Closed confined housing of animals minimize potential
pollution when wastes are properly disposed. Open feedlots present
the severest hazard to potential pollution: a 32,000 head feelot can
produce 1,400 metric tons of nitrogen yearly (comparable to the nitrogen
waste of 260,000 humans (NAS, 72)). The nitrogen content of the soil
under a Colorado feedlot was 1,143 pounds per acre compared to 403 pounds
per acre for irrigated fields, 208 pounds per acre for cultivated dry
lands, and 72 pounds per acre for native grasslands (NAS, 72). Pollution
potential from animal wastes is greatest when the waste is spread on snow
or frozen ground.
3. Soil Sediment and Heavy Metals
Soil sediment enters the nation's waters from all agricultural and silvi-
cultural segments, and it is a transport agent of heavy metals, pes-
ticides and plant nutrients. Any practice that increases(or reduces)
sediment transport affects heavy metals transport similarly. Slope, cover crop
cultivation practices, and timber harvest methods influence the amount of
sediment lost. EPA (76) estimates that 5,200,000 tons of sediment are
deposited in U.S. waters each day from cropland, 3,400,000 tons per day
from range and pasture land, 720,000 tons per day from forests, and
57,000,000 tons per day from urban sources. Exhibits II-2 and II-3 show
relative comparison rates of erosion stemming from various land uses.
The exhibits show total erosion from cropland is 168 times greater than
total erosion losses from commercial forests; however, no actual or poten-
tial erosion rates are available because of the localized nature of
erosion losses. Individual testing of sediment losses show ranges from
less than 1 ton per acre yearly to more than 21 tons per acre yearly.
Many tests reported values of 7 - 8 tons per acre per year (Dornbush, 74).
(Note: Multiple transport modes exist. Water flow may transport more
wastes, with less concentration, because of its high volume. Also, some
wastes, e.g., heavy metals, may be chelated with organic matter as well
as transported with sediment.)
4. Salinity
Salinity results from irrigated crop practices, as well as occurring
naturally, and affects the quality of ground water and surface water, and the
soil productivity. Irrigation techniques are now 30 - 70 percent efficient.
Practices which increase irrigation efficiency will demonstrate potential
benefits by decreasing salinity in soil and return flows.
5. Other Pollutants and Sources
Drugs, hormones, and other chemicals are used as implants and feed additives
to increase animal feed efficiency and rates of gain. Their use causes con-
cern because they may be present in animal tissues at slaughter. Some of
these residues are not destroyed by cooking, and the long term effects of
small doses on humans have not yet been determined.
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Exhibit II-2. Representative rates of erosion from various land uses
Forest
Grassland
Abandoned Surface Mines
Cropland
Harvested Forest
Active Surface Mines
Construction
Source: EPA, Methods for
Erosion
Metric Tons/
sq km/year
8.5
85
850
1,700
4,250
17,000
17,000
Rates
Tons/
sq mi/year
24
240
2,400
4,800
12,000
48,000
48,000
Identifying and Evaluating the Nature
of Non-Point Sources of Pollutants,
1973.
Relative to
Forest = 1
1
10
100
200
500
2,000
2,000
and Extent
Exhibit IT-3. Relative erosion from various
land uses: Nationwide
Relative Erosion Values
Conmerclal Forests (Erosion index base = "1"J 1
Abandoned Surface Mines < 1
Active Surface Mines 2
Construction 6
Harvested Forests 11
Grassland 11
Cropland 168
Note: This index represents approximate relative rankings of the con-
tributions of sediment (on-site), on a nationwide basis, from the seven
types of non-point sources listed in Exhibit II-2 above.
Source: EPA, Methods for Identifying and Evaluating the Nature and Extent
of Non-Point Sources of Pollutants, 1973.
10
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Wind erosion pollutes U.S. waters and degrades soil quality. Valuable
top soil is lost, land productivity may decrease and gullies may form.
Severely eroded land may also be aesthetically displeasing.
Other sources of pollutants may develop in the future. For example,
integrated pest management practices may be a source of additional
bacteria and viruses. Also, crop residues associated with no till
management practices may be a source of insect, rodent and disease vectors.
Surface run-off and leaching from animal waste disposal areas may in-
crease microbial populations in the soil and water, but they are not
considered serious pathogens. The size of the animal production units
and the type of waste disposal systems used will determine the signi-
ficance of microbial pollutant quantities.
Irrigation practices have resulted in lower ground water levels in many
sections of the U.S. and land subsidence is a severe problem in some
locations.
Smoke, dust, and odors arise from certain agricultural and silvicultural
practices and contribute to air pollution. Smoke comes from prescribed
and slash burnings in silviculture and agriculture. Wind erosion, culti-
vation practices, and harvesting methods create fugitive dust problems.
Odors arise from cattle feedlots and other animal production units.
Thermal pollution from silviculture raises the temperatures of some streams
above the endurance levels of some fish and enhances the foreutrophication
of streams. Forest streams!de cutting is the major cause of thermal
pollution.
B. Potential Environmental Effects of Pollutants
from Agriculture and Silviculture
The potential environmental effects of pollutants from agriculture and
silviculture often cannot be directly or separately assessed. Various
other sources of pollutants may be regularly mingled within common
environmental receptors -- streams, rivers, lakes, and airsheds; con-
sequently, synergistic pollutant effects and associated environmental
implications may result.
As an aid to assess the potential environmental implications of trends in
agriculture and silviculture, a schematic relationship of agriculture
(and silviculture) to other sources of pollution and their linkage to a
common environment is shown in Exhibit 11-4. Within this framework, the
ultimate end-uses of environmental resources (water, air, land) are shown
to be the main determinants of the environmental implications of concern,
for the impact of pollutants on subsequent uses of the environmental re-
sources gives rise to man's concern for pollution.
11
-------
Exhibit II-4. A flow diagram of sources of environmental pollution
and their implications
Producing and Consuming
Sectors
Residuals 1 <
Environmental Receptors
and
Pollutant Interaction
Environmental
Implications-Impacts
Agriculture and Silviculture
- irrigated croplands
- nonirrigated croplands production
- range and pasture production
- livestock production
- silviculture production
Other Sectors
- industrial
- municipal
- mining
L, - etc.
. Agriculture and Silviculture
- sediment
- nutrients
- pesticides
- salts
- heavy metals
- animal waste and microorganisms
- dust, smoke, odor
- etc.
. Other Sector's Pollutants
Water
Land
Air
Food Chain
Wildlife and Wildlife Habitat
Ecological Systems
Human Health
Agricultural Production
Recreation
Aesthetics
12
-------
Clearly, agricultural and silvicultural pollutants enter the earth's water,
air, and soil. Surface water and ground water have increased salinity,
sediment, pesticide residues, plant nutrients, easily oxidizable organics
from crop residues, pathogenic organisms, and heavy metals as a result of
agricultural and silvicultural practices. Pesticides, plant nutrients, and
salt contribute to soil pollution. Agricultural chemicals, dust, odor,
and smoke are sources of air pollution. Soil erosion, clear cutting, loss
of wetlands, and reduction of ground water levels all produce an impact on
the environment.
The assessment of these pollutants upon the environment is difficult, how-
ever, because although potentially harmful environmental effects do exist,
experimental data on their quantities and effects are inadequate. When
residue levels are obtained, they are usually at sublethal concentrations.
Since it is not possible to finitely assess their impacts on the environ-
ment, only their potential environmental effects will be considered here.
1. Water Pollution
By volume, sediment is the major pollutant in surface water, and it is also
the transport agent for other residues: nitrogen, phosphorus, pesticides,
bacteria, and heavy metals. Sediment obstructs stream drainage and irriga-
tion canals, fills reservoirs and lakes, and creates turbidity. It becomes
an obvious economic problem when it becomes necessary to clear canals and
reservoirs of sediment.
Surface and ground waters have increased salinity from irrigation practices.
Currently, there is no danger to human health from increased salinity in
surface waters (Color, 74), and its control is primarily an economic issue,
for it increases municipal and industrial water treatment costs and accelerates
oipe corrosion. High salinity levels result in unpleasant water taste,
hardness, and a loss of aesthetic quality.
Salt buildup in ground water directly affects crop yields which decrease
in all soils with excessive salinity. Crop production has become econom-
ically infeasible in areas of toxic salt levels. This results in lost
profits and productive agricultural land.
Increased levels of nitrogen compounds and phosphates in surface waters
lead to excessive algae growth which clutters streams and overburdens a
body of water's supply of dissolved oxygen. The resultant stagnation in
shallow water can cause (1) increased mosquito population and their
consequent threat to health, (2) a decrease in fish populations and other
aquatic life (3) an overall decrease in animal and human water use, and
(4) tastes and odors. From current available data, the possibility of
stagnation occurring in anything other than shallow streams and ponds (and
then only infrequently) does not seem likely (NAS, 72). High concentrations
of nitrates in livestock water has been reported to cause cattle illness
and death (NAS, 72). The chronic effects of sublethal doses of nitrates on
humans and animals are not well documented. Although, experiments show re-
duced productivity in animals with long term exposure to high nitrate
levels, animals are also known to adapt to long term nitrate levels.
13
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Seepage of ground water containing high concentrations of nitrates into
well waters is the major direct threat to humans from nitrates. The U.S.
Public Health Service has set 10 mg of nitrate per liter as the upper safety
limit, and many wells, as well as some surface waters, exceed these limits.
The U.S. has had 350 cases of nitrate poisoning (41 fatalities) in infants
reported since 1944 (NAS, 72). All but 5 cases were caused from well-water
nitrate poisoning.
Pesticide residues in surface and ground waters have been reported by many
investigators (Guenzi, 74; Edwards, 73; Dornbush, 74; Haque, 75). A wide
range of residue levels were found, ranging from undetectable amounts to
1,000 ppt for DDT, but an analyses of many rivers show that few exceed 10
ppt DDT or 5 ppt DDE (Edwards, 73; Holden, 75). Generally, all pesticides
are found in small concentrations within recommended limits. Of primary
concern are the high levels of pesticide residues found in the tissues of
birds, fish, and other aquatic life, for aquatic life can concentrate pes-
ticides at several times the level found in water (Edwards, 73; Holden, 75).
Tissues of fish used in the human food chain have been found to have pesticide
residues exceeding safety limits set up by FAO-WHO, and the excessive pes-
ticide loadings of streams caused by careless application or from accidental
dumps by pesticide producers have been reported to cause massive fish kills
(Edwards, 73; Nicholson, 67). Certain birds have impaired reproduction
rates caused by thin shelled eggs being produced when pesticide residue
levels are high. Other birds carry heavy pesticide levels in their tissue
with no apparent effects (Edwards, 73). The longterm effects of sublethal
doses of pesticides upon human and animal populations are not known. Although,
little evidence supports the idea that pesticide residue levels in our environ-
ment are widely harmful, it is impossible to prove otherwise as well. Recent
government investigations and independent research studies have implicated
certain pesticides and other related agricultural chemicals as possible
carcinogenic agents when ingested or inhaled, and previous "safe" limits
are being re-evaluated in light of these possible carcinogenic effects
(Environ. Sc., 76).
Little can be said on ground water pesticide levels. Obviously, high pes-
ticide levels can contaminate well water, but no cases of human deaths or
illnesses have been reported.
The thermal pollution of water by certain silvicultural practices (such as
streamside cutting) can cause adverse effects on some aquatic life. Tem-
peratures are raised to a level that certain fish cannot endure; however,
in some instances, the increased water temperatures can create a more
favorable environment for lower links in the food chain.
Bacterial contamination of surface waters from animal wastes have been
determined by a number of researchers (Dornbush, 74; Eunhle, 70), and this
is a potential hazard to human health. Salmonella bacteria, occasionally
found in animal wastes, may live in water and can cause Salmonellosis in
humans. One investigator (Kunhle, 70) found fecal and coliform counts,
after a storm run-off, to be greater than those acceptable for swimming
waters. The difficulty of analyzing data from bacterial counts in water
supplies stems from the inability to differentiate human from animal sources
of contamination.
14
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The major non-point heavy metal loading of surface waters is carried by
sediment. These metals are for the most part sparingly soluble in water,
so that little of the total metal load is solubilized in surface water.
Their impact on water quality is much less than what would be calculated
on the basis of the total load discharged into a water suoply (McElroy, 76).
Iron and maganese contribute the largest part of heavy metal load into
surface waters. Small amounts of arsenic, copper, lead, and zinc are also
carried into surface and ground water from sediment. Isolated tests of
high concentrations of these metals on fish, algae, and other aquatic life
have shown them to be toxic. Temperature, water pH, dissolved oxygen,
suspended solids, turbidity, as well as experimental condition variables
all influenced the measured degree of the toxicity of each metal; there-
fore, no uniform standards of toxicity values for the metals have been
reached by investigators. Most experiments have been carried out under
laboratory conditions and do not reflect the true incidence of aquatic
life poisoning by heavy metals (Battelle, 71). Because most of the
literature on non-point source pollution from agriculture does not make
mention of the potential environmental effects of heavy metals, these
effects may be minimal for surface and ground water (Dornbush, 74; USDA-
EPA, 75).
2. Soil Pollution
Increased soil salinity results in decreases in crop yields, land produc-
tivity, and profits. Salinity increases when irrigation practices such as
evapotranspiration remove water from the soil and concentrate its salts.
Both persistent and non-persistent pesticides are also found as residues
in soil. Persistent pesticides may remain chemically active in the soil
for several years; non-persistent pesticides disappear within a few months
of application. Of primary concern is the uptake by crops of soil pesticides
which contaminate foods. Monitoring by the U.S. government has found pes-
ticide residues in food to be well within the safety limits; thus, no
danger is posed to human health at this time (Edwards, 73). Theoretically,
pesticide buildup in the soil could present an economic threat through de-
creased crop yields; however, there is little evidence to support this
theory. Pesticide residues may be considered a potential environmental
threat if projected increased pesticide levels are realized. Pesticide
residues may also affect soil microbial populations. Soil microbes are
often necessary to maintain proper ecological balances, for they aid in
nitrogen fixation, are sometimes the natural predators of plant pests, and
often provide other natural benefits to plants. Although soil microbial
populations may be slowly altered by pesticide residue levels, little
documented evidence exists to support this theory (Guenzi, 74; Edwards, 73),
and studies do show that pesticides applied in proper doses are not likely
to acutely affect the microbial population.
15
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3. Air Pollution
Agricultural and silvicultural residues contribute to air pollution. Pes-
ticide application by aerial sprays result in drift losses, and pesticides
may also volatilize into the air after soil application. The ranges of
pesticide levels in the atmosphere were found from 0.0003 ppt to 0.158 ppm
with a mean level of 0.01 ppb to 0.002 ppt (Edwards, 73). Research in-
dicates that human inhalation of 2 - 32 ug of pesticides per day is possible
(Tabor, 66), but since this represents only 2-5 percent of the total up-
take of pesticides by a human (ARC, 70) it is probably not significant.
Instances of illnesses and deaths from pesticide poisoning have been
recorded, but these have resulted from direct contact during aerial appli-
cation or from an individual being in the proximity of a freshly, heavily
sprayed field (Edwards, 73). (The oossible carcinogenic effects of pes-
ticides when ingested or inhaled were previously discussed.)
Dust from agricultural practices such as harvesting and wind erosion enters
the air as a pollutant and is a carrier of pesticides, plant nutrients, and
heavy metals. While dust may be irritating to eyes, nose, and throat, and
have detrimental effects on people suffering from bronchial illnesses and
allergies, its effect on the environment is usually synergestic. By itself,
dust is not significant as an environmental threat, but in conjunction with
chemical residues, industrial and municipal effluents, auto exhaust, and other
air pollutants, it will contribute to the overall degradation of air quality.
Odors arising from feedlots and dairy farms are aesthetically displeasing.
Odors are objectionable, and they occasionally cause minor illnesses. The
potential environmental effects of odors are limited, and they are not
generally considered harmful to human or animal health.
Smoke results from some silvicultural, and range and pasture land manage-
ment practices. Smoke is temporary and it has no lasting effects upon
the environment.
4. Potential Environmental Pollution From Other
Agricultural and Silvicultural Practices
Soil erosion results in losses of valuable top soil, changes soil structure,
increases gully formation, decreases soil productivity, hampers farming
operations, and increases costs for land renovation. In some instances,
land may be left completely non-oroductive and aesthetically displeasing.
Drug and chemical residues in animal tissue for human consumption are a
potential threat to humans. Even after cooking foods for long time
periods, some drugs still remain chemically active in beef and pork. Current
research seeks to determine the possible carcinogenic effects of these drug
residues.
The conversion of forest land into cropland, pasture, and range land, the
draining of wetlands for agricultural usage, and the stocking of range lands
all disrupt ecological systems. Wildlife, wildlife habitat, and recreational
areas are changed and often lost when land is put into productive agricultural
use. Proper management practices will minimize these environmental effects.
16
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The increasing usage of irrigation has lowered ground water levels to
dangerously low levels in certain sections of the U.S. Eventually, many
areas utilizing groundwater supplies will have to revert to their former
land uses or be abandoned as water supplies become depleted.
C. Pollution Effects on Silviculture and Agriculture
The above discussion highlights the effects of agricultural and silvi-
cultural pollutants on the environment; however, it is generally recognized
that both agriculture and silviculture production systems may also be
impacted by polluted environments. Pollution that affects agriculture
and silviculture arises from three principal areas: municipal and indus-
trial air pollution, municipal solid-waste disposals on agricultural lands,
and salinity buildup from irrigation return flows.
Agricultural cropland and forests existing in close proximity to large
cities may suffer significantly from air pollution. Ponderosa pine trees
above the Los Angeles Basin are being killed from that city's air pollution.
Chemicals in the air may cause leaf rot and other plant diseases. Leaf
foliage is often coated with a layer of grime or chemical which screens sun-
light and results in lower photosynthesis and plant evapotranspiration rates.
Lead from automotive exhaust is deposited in the soil and is available for
olant uptake. The total impact of air pollution on agriculture is difficult
to assess, for its effects are localized and do not affect a large sector
of agriculture. Field crop areas are usually affected less than large
vegetable farm areas since the latter are often located close to cities.
Heavy metal contamination of soil and crops is the chief adverse effect of
municipal solid waste disposal on agricultural lands. Crops concentrate
heavy metals. Also, beef cattle fed corn silage grown on sludge sites can
concentrate the heavy metals in their tissues, and the human consumption
of this beef will result in further concentrations of these metals. Heavy
metals deposited on the soil are also available for ground and surface water
contamination. Ocean dumping of waste is not permitted because heavy metal
concentrations adversely affect marine life. Heavy metals concentration
in surface waters affects aquatic life. Industrial pretreatment to remove
heavy metals would eliminate most adverse effects that stem from municipal
waste. Although a potential threat does exist from human pathogens infecting
crops and animals, various pathogen treatments and control procedures make
this highly unlikely.
Agriculture adversely affects itself through its salinity buildup from
irrigation practices. The need to use available water more efficiently
has led to using irrigation return flows whose residue salts will further
concentrate soil salinity. Agricultural productivity may suffer from this
increased soil salinity.
17
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SECTION III
A SCENARIO OF THE FUTURE: 1976-2010
An assessment of the environmental implications of trends in agriculture
and silviculture requires, minimally, the establishment of a baseline
projection of these sectors of the economy. Such a baseline projection,
i.e., scenario of the future, is presented below for both the short-term
(1985) and the long-term (2010). Alternative scenarios are obviously
possible, and the associated environmental effects would differ from the
baseline case. However, this study seeks to thoroughly survey and delineate
all trends and developments within agriculture and silviculture that have
major environmental implications. A single and widely accepted scenario
of the future: 1976-2010, has been incorporated herein to accomplish the
main objective. Additional research, beyond the scope of this study, is
needed to assess the effects of alternative futures.
A. Output Projections
Future production levels and product mixes of the agricultural and
silvicultural sectors are clearly based upon variables whose future
values cannot be precisely determined. Thus, innumerable projections
can be obtained by assuming various rates of growth for these variables.
Since it was necessary to establish a firm baseline upon which the sig-
nificance of the future environmental trends could be measured, known
and generally accepted projections were utilized: ERS projections for
1985 (USDA, 76) and the OBERS projections for 2010 (USWRC, 1975). Inherent
in the models on which these projections were based are assumptions
concerning variables such as population, economic growth, technological
advance, housing starts, and international trade. For reference, these
assumptions are discussed further in section C, below. An additional
assumption germane to the present study is that current environmental
policies will remain constant through 2010.
The ERS and OBERS projections of selected key variables are given
numerically in Exhibit III-l and graphically in Exhibit III-2. These
projections reflect moderate rates of growth. Exhibit III-l indicates
that U.S. population is expected to increase from about 210 million
in 1972-74 to 235 million in 1985 and 281 million in 2010. Estimates
by the Bureau of the Census (Series E) assume a fertility level of
2,100 per 1000 women by 2005 and zero population growth levels by mid-
century. The Gross National Product (total man hours employed x output
per man hour) is expected to increase to $2,890 billion (1958 dollars)
18
-------
by 2010. This projection assumes that output per manhour will increase
2.9 percent annually and that total manhours worked will decrease at a
rate of 0.35 percent per year. Housing starts, an indicator for the
most important consuming sector of processed wood, will increase 40
percent over 1972-74 by 2010.
Per capita personal income, an alternative measure of economic growth,
is expected to increase to $9,370 (1958 dollars) by 2010.
Exhibit III-l. Exogenous variables: Projections under moderate growth
assumptions on population, per capita personal income, housing starts,
and gross national product with current environmental controls
Variable
Population
Unit
Million
1972-74
210.4
Index (1972-74 = 100)
Current 1985 2010
100 111 134
Gross National Product Billion of
1958 $ 817.0
Per Capita Personal
100
147
354
Income
Housing Starts
Agricultural Output
Index
1958 $
Million
1967=100
3,155.0
1.93
110
100
100
100
150
133
118
297
140
151
Exhibit III-2. Exogenous variables: Graphical representation under
moderate rates of growth
400
6NP
8
i
CM
300
200
100
•4-
1972-1974 1985
Per capita
Personal Income
Ag Output
Housing Starts
Population
2010
Year
19
-------
The trend in foreign demand is influenced by such variables as world
population growth, production capacity, market conditions, and weather.
Interruption in foreign demand caused by temporary fluctuations in
foreign production levels make predictions difficult; however, it was
generally felt that these disturbances would tend to show an upward
bias from the permanent trend. In silviculture, imports and exports
do not significantly affect U.S. supplies. The silviculture export
variable is not as important in its effect upon production as is that
for agriculture.
Agriculture and silviculture technological advancements defy precise
measurements. They are expected to advance but at a slower rate than
that which has occurred over the last two decades.
The baseline agriculture and silviculture production projections for
1985 and 2010 are given in Exhibit III-3. The 1967-based agricultural
output index is projected to increase from 110 in 1972-74 to 130 and 166
in 1985 and 2010 respectively. Of the major grain crops, soybeans is
expected to grow most dramatically to the year 2010, with growth projected
at 228 percent from the 1972-74 average production of 1,350 million
bushels. Corn (5,290 million bushels in 1972-74) and wheat (1,681 million
bushels in 1972-74) are projected to grow 75 percent and 26 percent
respectively over the same time period. Beef production will increase
from 22,700 million pounds in 1972-74 to 39,600 million pounds in 2010,
a growth of 75 percent. Pork will increase 49 percent in the same time
period.
Timber, roundwood basis, is projected to increase by 119 percent to 25,200
million cubic feet by the year 2010. Pulpwood shows the most significant
rate of growth, increasing from 3,800 cubic feet (1972-74) to 12,500 cubic
feet (2010) which is a 229 percent growth.
B. Resource Availability
The availability of resources for agriculture and silviculture should
not present a production constraint of any significance to the year
2010. Supplies of important minerals and chemicals used in the pro-
duction of fertilizers and pesticides will be adequate. Neither energy
nor land should constrain production to the year 2010.
The current and projected agricultural use of fertilziers, pesticides,
cropland harvested, and energy are given in numeric form in Exhibit III-4
and graphically in Exhibit III-5. Total agricultural production will in-
crease by 51 percent from 1972-74 to 2010. To achieve this level of
production, the key inputs will also increase: nitrogen fertilizer will
increase by 106 percent, pesticices by 118 percent, and energy by 10
percent. Harvested croplands will increase by 14 percent.
20
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Exhibit III-3. Projections by commodity for selected years 1985
and 2010 under moderate growth assumptions
Commodity
Crops
Wheat
Rye
Rice
Corn for grain
Silage
Grain Sorghum
Oats
Barl ey
Fruits and nuts
Vegetables
Hay
Soybeans
Flaxseed
Peanuts
Cotton
Sugarcane
Sugarbeets
Tobacco
Irish & sweet potatoes
Dry beans & peas
Livestock
Beef and veal
Pork
Lamb and mutton
Chickens
Turkeys
Eggs
Milk
Timber
All roundwood
Sawlogs, veneer logs &
other industrial
products
Pul pwood
Farm output index 1967=1
Mi 1 1 i on
units
bu.
bu.
cwt.
bu.
tons
bu.
bu.
bu.
Ibs.
cwt.
tons
bu.
bu.
Ibs.
bales
tons
tons
Ibs.
cwt.
Ibs.
Ibs.
Ibs.
Ibs.
Ibs.
Ibs.
doz.
Ibs.
cu. ft.
cu. ft.
cu. ft.
00
72-74
1,681
24.9
88
5,290
140l/
789
660
384
48, 41 32/
49,457
130
1,350
14.4
3,476
12.7
16.9
25.1
1,828
324.8
2,167
22,669
13,384
509
9,028
2,569
5,610
1,169
ll,525l/
"D /
6,7684V
3,800^
no
1985
1,764
40
118
6,618
146
1,132
885
550
48,795i/
56,745
140
1,835
28.0
4,813
10.7
19.7
33.6
2,140
367.9
2,234
30,051
15,745
195
11,973
2,639
6,353
1,211
17,170
10,000
6,676
130
2010
2,109
51.4
159
9,271
174
1,664
1,106
699
58,603
70,416
173
3,071
23.9
6,998
10.8
26.5
43.2
2,348
446.1
2,245
39,563
19,979
202
16,136
3,727
7,349
1,273
25,200
12,100
12,500
166
iy Production for 1971
2J Citrus and non-citrus fruits only
37 Preliminary
Source: ERS, Agriculture the Third Century, USDA, 1976. OBERS, 1972 OBERS
Projections Supplement, U.S. Water Resources Council, 1975.
21
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Exhibit III-4. Projections index for agricultural resources for
selected years 1985 and 2010 under moderate
growth assumptions
Variable
Cropland Harvested
Fertilizer
Nitrogen (N)
Phosphates
Potash (k20)
Pesticides
Energy
Agricultural Output Index
Unit 1972-74
Million
acres
Million of
tons
Million of
tons
Million of
tons
Million Ibs
Billion gals
1967=100
311
8.2
5.0
4.7
8.0
no
Index (1972-74 =100)
Current
100
100
100
100
100
100
100
1985
102
146
110
119
166
101
118
2010
114
206
122
140
218
no
1M
Sources: ERS, USDA estimates and DPRA projections
Exhibit III-5. Agricultural resources: Projections under moderate
growth assumptions
§
s
5
•o
220 •
200 •
180 •
160
140
120
100
1
1972-1974
1985
Pesticides
Nitrogen Fertilizer
Agricultural Output
Potash Fertilizer
Phosphate Fertilizer
Energy
2010
Year
22
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Fertilizer and pesticide use in silviculture has been minimal, although
under current projections, some 10.6 million acres of commercial forest
land are eligible for potentially viable fertilizer treatment. Specific
fertilizer use projections for forest growth vary widely and have not
been projected by ERS or OBERS.
In 1972, 830,000 forest acres, significantly less than one percent of
the commercial forest lands, received insecticide application. Since
insecticides are used on an as-needed basis, their application fluctuates
year by year and region by region. In 1972, 490,000 acres were treated
with herbicides. At an application rate of 2.9 pounds per acre, the
estimated annual consumption level was 710 tons.
An examination of Exhibit III-6 reveals that 400 million acres or 27.8
percent of the total U.S. acres are classified as cropland and 375
million acres or 26 percent are classified as forest. The 400 million
acres of cropland includes idle cropland, summer fallow, and cropland
harvested. With a projected cropland harvested in 2010 of 355 million
acres, sufficient land presently considered "cropland" exists to meet
demand under baseline conditions; however, if demand is significantly
above the assumed level, 111 million additional acres of land considered
"high" and "medium" in conversion potential are available for crop pro-
duction (SCS, 1976).
A breakdown in acres by potential category and development needed
classification is given in Exhibit III-7 and a breakdown of current use
is presented in Exhibit III-8. Of the 111 million acres, high and medium
conversion potential land, 24 million acres would require only tillage
to bring it into production. An additional 74 million acres would require
efforts by individuals (e.g., removing stones or improved management
techniques) to make production possible. This additional land will pro-
vide an ample reserve should demand warrant its use.
Forest lands are projected to decline by about 4 percent by 2010--a
result of both reductions of and additions to "commercial" forest land.
The forest lands in 2010 are also expected to be managed in a variety
of ways ranging from the retention of stagnating old growth in the West
to accelerated pulp rotations in the South.
C. General Assumptions
The OBERS projections are based on long run-secular criteria that adjust
for the cyclical fluctuations which consistently characterize the shortrun
path of the national economy. The general assumptions that underlie
the projections are as follows:
23
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Exhibit III-6.
Distribution of U.S. land by use category (estimated
acres) 1975
Pasture And
Range
39.6%
Water
0.5%
Urban
Use Category
Cropland
Pasture and Range
Forest
Other Land
Urban
Water
Total
Acres -
400,416,747
570,880,743
375,448,062
69,830,326
16,635,613
6,708,738
1,439,920,
-I Excludes Alaska and Hawaii
Source- United States Department of Agriculture, Soil Conservation Service,
"Potential Cropland Study", Wushincjton, D.C., 1976 (Preliminary).
24
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Exhibit III-7. Potential for cropland with development necessary
by land uses (estimated acres) 1975 I/
Development
Necessary
Pasture and Range
None
On-farm
Multi-farm
Project action
TOTAL
Forest
None
On-farm
Multi-farm
Project action
TOTAL
Other Land
None
On-farm
Multi-farm
Project-action
TOTAL
High Potential
(acres)
30,794,671
23,301,705
1,091,440
1,869,187
62,057,003
260,010
12,006,286
355,712
719,583
13,341,591
919,341
1,866,897
51,255
30,856
2,868,349
Medium Potential
(acres)
4,894,499
13,846,315
734,150
617,256
20,092,220
46,138
8,481,315
656,751
1,683,521
10,867,725
225,817
1,038,001
84,909
495,857
1,844,584
V Excludes Alaska and Hawaii
Source: United States Department of Agriculture, Soil Conservation Service,
"Potential Cropland Study", Washington, D,C., 1976,
25
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Exhibit III--8. Sources of "potential cropland" by current use
(estimated acres) 1975 I/
Medium Potential
1.
High Potential
4.3X
High Potential
0.9%
Medium Potential
0.3%
Medium Potential
0.72
Note: High and Medium Potential Cropland
Tc'.il Potential C, ^plav.d Acres - 111 million acres
Percent of Total Land =7.7
Percent of 1975 Cropland ^= 27.7
-• Excludes Alsaska and Hawaii
Source: United States Department of Agriculture, Soil Conservation
Service, "Potential Cropland Study," Washington, D.C. 1976.
-------
(1) Growth of population will be conditioned by a fertility
rate which represents "replacement level fertility."
(2) Nationally, a "full employment" rate (includes 4 percent
unemployment) will prevail at the points for which pro-
jections are made. As in the past, unemployment will be
disproportionately distributed regionally, but the extent
of disproportionality will diminish.
(3) The projections are assumed to be free of the immediate
and direct effects of wars.
(4) Continued technological progress and capital accumulation
will support a growth in private output per manhour of 2.9
percent annually.
(5) The new products that will appear will be accommodated
within the existing industrial classification system, and
therefore, no new industrial classifications are necessary.
(6) Growth in output can be achieved without ecological disaster
or serious deterioration although diversion of resources for
pollution control will cause changes in the industrial mix
of output.
In dealing with projections, a margin of sensitivity should be con-
sidered. The projections given represent levels of production and
utilization that would occur should the underlying assumptions hold.
For example, the export demand component is not likely to follow a
steady secular trend. It has been assumed that this variable will grow
moderately, but the last few years has demonstrated that rapid increases
in demand can occur as unexpected interruptions.
Food production is likely to vary seasonally due to the fluctuation
of weather and climate. Unfortunately, current forecasts cannot produce
reliable predictions of future conditions. Thus, it was necessary to
assume normal weather with poor and above normal conditions averaged
over time.
Current environmental standards have been assumed to remain intact
throughout the projection period. Any signficant movement toward
more stringent controls is likely to reduce agriculture production.
Changes likely to be made under stringent controls would be, for ex-
ample, the mandatory rather than the voluntary adoption of certain con-
servation practices, restrictions on use and formulation of fertilizers
and banning of certain pesticides for all uses.
27
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The development of regulations upon silviculture for environmental
protection has been accelerating. While protecting the environment,
these regulations are increasing costs of harvest and administration.
It was assumed that despite additional costs, the rate of harvest will
not be affected appreciably. In addition, the Forest Service has
withdrawn areas in the West, especially in the Rocky Mountain Region
for further study as wilderness areas. It was assumed that no further
withdrawals of high-site commercial forest land will occur during the
projection period.
Small private ownerships provided 49 percent of the nation's roundwood
needs in 1970. By 2010 private holdings are expected to provide 57 per-
cent of a total consumption figure that will have more than doubled.
If this level of production is to be met, this private non-industrial
sector must practice more intensive management. It was assumed that
enough private forest land will come under management to provide the
volumes projected.
D. Function of Moderate Growth Scenario
Doubtless, a scenario descriptive of long-term economic and technological
conditions and developments is tentative at best. Problems attendant upon
population, energy resources, world trade, and international social needs
are not susceptible to quantifiable definition that a definitive long-term
analysis would require. Too, the present technological sophistication of
agriculture and silviculture — their response to increasing mechanization,
greatly varied and changing agronomical cultural practices, and an increasing
reliance on constantly developing chemical and biological agents -- has re-
sulted in a rapidly altering agro-technical science that precludes an in-
vesigator's knowing with assurance what the future technological profiles
of these economic sectors will be. Thus, though analysis be thorough and
consistent, researchers must nevertheless recognize that best projections
and assumptions cannot be ultimately descriptive of so varied and complex
an entity as long-term food and fiber needs and scientific response to them.
Obviously, then this study's foregoing projections and assumptions, though
based on the generally accepted ERS and OBERS models, remain suppositional.
The study uses a moderate growth model, in part because moderate growth
is a reasonable and measurable assumption, and in part, because such a
projection does not necessitate the use of a highly distorted and most
tentative set of assumptions concerning agri-science's technological de-
velopment. It must be realized, also, that the assumption of a moderate
growth model rather than a uniquely different one or even alternate sets
of assumptions is consistent with the purpose of the study. The scope of
the study does not envision the construction of indices attempting to
quantify in precise terms the environmental impact of agricultural and
silvicultural practices and inputs in either the short or the long term,
28
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for such indices would be but tentative. The rationale for the study,
rather, is that it should seek to identify, classify, and rank in their
order of magnitude the present and probable trends in agriculture and
silviculture which will effect either beneficial or deleterious environ-
mental change. To the extent reasonable, such trends and their consequent
effects should, additionally, be ranked in relative order and be assigned
terms indicative of the extensiveness and intensiveness of their effects
upon the environment.
The overall relationships and the relative environmental effects of the
various trends will not appreciably change under any but the most extreme
scenario variations. To be sure, for instance, an extensive long term
drought over a wide geographic area affecting a substantial portion of
world population would create an export demand for agricultural products
so encompassing that it would severely impact agricultural practices.
The resulting need to employ marginally productive acreage and chemical
and biological agents would be great enough to distort seriously the
"normal" relationships among the applicable agricultural trends and their
environmental effects. But though such a possibility may exist, its
unpredictability and unknown specificity make it unreasonable to attempt
a measurement of it. Such would be true of any extensive distortion
of the generally accepted growth patterns incorporated in the ERS and
OBERS projections used in the present study. Thus, the reader, in con-
sidering the foregoing scenario and its specific measurements, must recog-
nize that the scenario is essentially a means to an end, a baseline pro-
jection by which the central purpose of this study is forwarded. Seen in
this light, the study's use of a moderate growth pattern is both instru-
mental and reasonable.
29
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SECTION IV
THE EVALUATION WORKSHOP
As mentioned previously (Section I: "Introduction") the Contractor's ten-
tative analysis of the environmental effects of agricultural and silvi-
cultural trends and management practices was submitted to an evaluation
workshop for review and, where necessary, elaboration. Initially, the
Contractor researched the study by examining pertinent economic and agri-
culture and silviculture data and by consulting with appropriate specia-
lists in germane disciplines. This initial research resulted in a pre-
liminary report which (1) defined acceptable resource and demand projections,
(2) identified and categorized agricultural and silvicultural sectors, (3)
classified and characterized the major production practices and trends in
those sectors, (4) described currently available measurements of the en-
vironmental effects of those practices and trends, and (5) designed the
evaluation procedures applicable to the examination of the study's pre-
liminary findings. The reoort became the working document used by the
evaluation workshop to assess the overall and the specific assumptions
of the Contractor's preliminary findings. The preliminary report in
large part is reflected in the present study in Sections I, II, and III,
in the various Part C: "Background Summary" portions of Sections VI - X,
and in the "Appendix B."
The present section briefly describes the evaluation workshop and its pro-
cedure and offers a general description of its participants.
A. The Evaluation Workshop
Under the sponsorship of the U.S. Environmental Protection Agency (EPA)
and its Environmental Research Laboratory, Athens, Georgia, an Evalu-
ation Workshop was held February 1-4, 1977 in Athens, Georgia to assess
the environmental implications of selected key trends in agriculture and
silviculture. These selected trends were defined prior to the workshop
in the preliminary report which was prepared as a working document for
the workshop by Development Planning and Research Associates, Inc. and
the Tuolumne Corporation.
During the workshop, a single "scenario" of moderate growth rates in the
general economy, including agriculture and silviculture, was assessed
from 1976 to 2010, i.e., basically the OBERS E1 projections to 2010.
Both higher and lower demand cases were perceived as plausible, but the
30
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limited time for the workshop necessitated that only the moderate case
be evaluated.
The workshop participants evaluated the environmental significance of
principal environmentally related trends and developments in agriculture
and silviculture as identified by the Contractor. Moreover, the workshop
participants were free to modify, re-group and/or add or delete trends
as they deemed appropriate. Their evaluations included judgments of both
the short-term and long-term significance of the selected trends and de-
velopments, but the primary focus of the workshop was on the long-term
future, i.e., 2010.
Two types of rankings of trends were determined by the Workshop. First,
rankings of the major trends in each of five panel areas were determined
by each respective panel, i.e.,
Agriculture
Panel 1: Nonirrigated Crop Production
Panel 2: Irrigated Crop Production
Panel 3: Feedlot Production
Panel 4: Range and Pasture Management
Silviculture
Panel 5: Silviculture and Harvest Management
In particular, each panel identified the ten most significant environ-
mentally related trends (whether beneficial, adverse or both) in their
own panel area.
Second, the five most important trends from each panel were assessed and
ranked by the workshop participants collectively. (Subsequently, during
the workshop, agriculture and silviculture trend rankings were independently
grouped as explained below.) Caution is advised when interpreting the
overall agriculture trend rankings since some panel trends (ranked 6 to 10,
for example) may justifiably have been among the major twenty if the Work-
shop procedures had permitted more than five trends from any one panel
to have been evaluated in the overall rankings. In other words, although
20 major trends from four agriculture panels (5 trends from each) were
ranked, these trends are not necessarily the 20 most significant environ-
mentally related trends in agriculture.
B. Workshop Procedures
The evaluation workshop consisted of an alternating series of general
sessions and individual panel sessions as indicated in the Workshop
Agenda, Exhibit IV-1. The proceedings were so structured that specific
forms were to be completed at each panel session and results summarized
at the general sessions. The eight forms that were utilized are in-
cluded in the Appendix.
31
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Exhibit IV-1.
Environmental implications of trends in agriculture
and silviculture
WORKSHOP AGENDA -'
AGENDA
TUESDAY - FEB. 1
REGISTRATION
WEDNESDAY - FEB. J
BREAKFAST
GENERAL SESSION I
PANEL SESSIONS I
LUNCH
PANEL SESSIONS II
DINNER
TIME
8:00 p.m.
ACTIVITY
7:15 a,
8:00 a,
8:30 a.m.
m.
m.
10:30 a,
11:00 a,
12:00 p.
1:00 p.
3:00 p.m.
3:30 p.m.
5:00 p.m.
6:00 -
7:00 p.m.
PANEL SESSIONS III 7:30 p.m
9:30 p.m.
Arrive from Atlanta (Charter Bus)
Light buffet supper
Registration and informal discussion
Group breakfast (designated dining area)
Registration (late arrivals)
Opening remarks - George Bailey, EPA
Introduction of Participants - Ray Seltzer, DPRA
Welcome
. Henry Garren, Dean of Agric., U.of Ga.
. David Duttweilar, Director of Environmental
Research Laboratory, Athens, Ga.
Overview of agriculture and silviculture:
1976-2010 - Sam Unger, DPRA and
Pete Arnold, Tuolumne
Briefing on workshop procedures - Gary Davis, DPRA
Break
Five panels meet separately (designated areas)
Chairman leads - EPA and Contractor arc
resource people only
Begin Form 1 - Extensiveness values
Group lunch (designated dining area)
Complete Form 1 (before break)
Begin Form 2 - Intensiveness values
Break
Complete Form 2 (before adjournment if possible)
Adjour panel sessions
Group dinner (designated area)
Complete Form 3 - Environmental implications
ratings and adjusted ratings
Determine top 5 and second most important 5
environmentally related trends
Complete Form 4 - Summary of ratings and
rationale
Chairman outline panel presentation
Adjourn
Submit panel's Form 4 to DPRA representative
. DPRA prepare all panel summaries for subsequent
distribution
S. Environmental Protection Agency, Environmental Research
Under Contract by Development
Sponsored by the U
Laboratory, Athens, Georgia, February 1-4, 1977.
Planning and Research Associates, Inc., Manhattan, Kansas and the Tuolumne
Corporation, Belvedere-Tiburon, CA.
32
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Exhibit IV-1 (continued)
AGENDA
THURSDAY - FEB. 3
BREAKFAST
GENERAL SESSION II
TIME
ACTIVITY
LUNCH
GENERAL SESSION III
PANEL SESSION IV
DINNER
FRIDAY - FEB. 4
BREAKFAST
GENERAL SESSION IV
LUNCH
7:15 a.m. Group breakfast (designated dining area)
8:30 a.m. . Distribute panel rating summaries (top 5,
plus next 5)
. Panel chairmen present top trends
. Discussion of each panel's results
10:00 a.m. . Break
10:30 a.m. . Continue panel rating summaries and discussions
12:00 p.m. . Group lunch (designated dining area)
1:00 p.m. . Finish panel rating summaries and discussion
(prior to break if possible)
2:30 p.m. . Break
3:00 p.m. . Each panel rank 25 major trends (top 5
from each panel)
Complete Form 5
. Chairman outline panel presentation
5:00 p.m. . Adjourn
. Submit panel's Form 5 to DPRA representative
. DPRA summarize panel findings on Form 6
6:30 - . Dinner banquet (Charlie Williams' Pinecrest Lodges)
9:30 . Transportation provided per instructions
7:15 a.m. . Group breakfast (designated dining area)
8:30 a.m. . DPRA present summary of all panel's
rankings - Form 6
. Panel chairmen present rationale for
panel's rankings
. Limited discussion
10:00 a.m. . Break
10:30 a.m. . Each participant rank 25 major trends
independent of panel - Form 7
. Each participant add trends from his panel
which should be in top 25 (from trends 6
to 10 only) - Form 8
11:00 a.m. . Workshop Wrap-Up
. Ray Seltzer, DPRA
. Pierre Crosson, RFF
. George Bailey, EPA
11:30 a.m. Adjourn
11:45 a.m. Group lunch
12:00 p.m. Air transport bus arrives for loading
1:00 p.m. Bus leaves for Atlanta (Estimated arrival
at 3:00 p.m.)
33
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These procedures were discussed in the report which was distributed
to the workshop participants prior to the meeting and again during
the first General Session of the workshop.
The evaluation procedure also involved the use of a rating system as is
explained in Exhibit IV-2. Each trend (or prospective development) was
rated in relative terms for both its "extensiveness of use" and "inten-
siveness of effect" to yield a multiplicative rating:
Environmental ... . . ..
Implications = Extensiveness of Use X
Rating Intensiveness of Effect
or,
R = E X I,
as defined in Exhibit IV-2. This rating procedure was used within each
panel to establish relative ratings among the trends (subtrends). These
ratings were then used as the basis for ranking trends within each panel.
The "intensiveness of effect" rating, (I), should be noted in particular.
By definition, for the workshop, a trend could have either a beneficial
(+) effect or an adverse (-) effect on the environment in 2010 compared
to its effect in the current period (1976). It was also possible for a
trend (subtrend) to have both beneficial and adverse effects upon the
environment. For example, conservation tillage would reduce soil erosion,
but generally require increased pesticide usage.
The extensiveness (E) and intensiveness (I) ratings within panels were
applied to subtrends within trends, rather than the overall trend, per se.
That is, as shown within each panel summary, trends are usually comprised
of two or more components. These components identify much more specific
management practices or developments (including emerging technological
developments which are projected to be important by 2010). Hence, a
"trend" in this analysis is generally a cluster of subtrends, and the
reader is advised to assess the component parts to better understand
the meaning of the trend. (In fact, some trend labels appear as "problems'
not as "trends." However, by assessing the subtrends, the proper inter-
pretation can be made of the trend. This topic is discussed further in
Section V, below.)
The panels of experts were permitted, furthermore, to adjust their en-
vironmental implications rating, R, following their initial assessments
of each trend. This adjusted rating, AR, best reflects each panels'
34
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Exhibit IV-2. Rating system definition for the assessment of environment
implications of trends in agriculture and silviculture
Environmental
Rating
R
4(1 -25)
. Extensivcness Intcnsivcness
of Use * ••• Effect
(E)
0-5)
x (I)
1 (1-5) 1'
where,
Rating:
Factor 1:
An Index of the overall environmental significance of a
trend or development in terms of both the scope of the
trend (E) and the seriousness of the environmental impli-
cations (1) of the trend. R Is the product of the ratings
for E (1 to 5) and for I (+ 1 to 5) as defined below.
Extenslveness of use of the trend (current or projected).
Criteria shall include:
(1) geographic scope (national vs local)
(2) degree to which total acreage or sector ouput
of the nation is impacted
(3) Other (define)
Factor 2:
A rating of 1 to 5 shall be qualitatively and subjectively
determined for each trend or development as follows:
Rating Scale
1
2
3
4
5
Description
liinor significance
(limited)
moderate significance
(important)
najor significance
Intenslveness of effect of the trend (Including Its persistence
and, potential Irrsverslb'.lHy of effsct.). Criteria shall include:
human health effects
ecological system disruptions
wildlife and wildlife ..a bit at effects
recreation effects
aesthetic consequences
yields, production, and associated effects
other (define)
A rating i,.' *(l-5) shall be Qualitatively and subject'vely
determined for esch "unit" of production to which the trend or
development applies, i.e., Irrespective of scope of the trend.
A plus(+) rating denotes t positive or beneficial effect on the
environment (on balance); whereas, a negative (-) rating denotes
i negative or adverse effect on the environment (on balance).
The ratings shall be as follows:
Rating Scale
+ or -
+ or -
•» or -
t or -
Description
minor significance
(limited)
nod.--ate significance
(Important)
major significance
beneficial, (-) ' adverse
Each factor shall be rated on a scale from 1 to 5 (E has positive values only
whereas I nay be either positive or negative, representing beneficial or adverse
environmental effects, respectively). These factors, when multiplied, may yield
in environmental rating, R, from + (1 to 25). Relatively high absolute, ratings
will denote the most important environmentally related trends, whereas relatively
low absolute scores will denote the less significant environmentally related trends.
The $TglTb7~the rating plus (+) or minus (-) will denote whether the trend Is
tlther beneficial or adverse on an aggregate basis. Special remarks should ac-
company this overall rating In the case of conflicting/offsetting beneficial and
adverse environmental components to explain the resolution of the conflict.
Each selected trend or development In agriculture and silviculture Is to be
Judged based on the rating scales as defined. Relative ratings, R, across
trends provides a conmon basis for qualitatively ranking major environmentally
related trends In agriculture and silviculture.
35
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value judgements of the relative significance of each trend's environ-
mental implications by 2010. As is explained in the discussion of the
panel sections below, each panel utilized the rating system somewhat
differently to arrive at its judgements of the leading trends that will
have associated environmental effects. I/
In most instances, the panels would have preferred to have regionalized
their results, subdivided their area into more specific production seg-
ments, and taken more time to assess the temporal dimensions of the prob-
lem. Nevertheless, the final rankings by each panel at the national level
were determined with generally firm agreement as to the trends' relative
importance vis-a-vis environmental change from the current period (bene-
ficial and/or adverse).
After the rankings within panels, each panel submitted its five top trends
to the entire workshop in general session for review and discussion. The
participants then returned to panel sessions to determine a combined ranking
of all of the panel's leading five trends. As is explained below, in the
final ranking, the trends of agriculture were separated from the trends of
silviculture, resulting in a ranking from 1 to 20 of the major trends from
agriculture, and a ranking from 1 to 5 of the major trends from silviculture.
Finally, upon completion of the workshop rankings, each participant was also
given the opportunity to rank the trends independent of his panel.
C. Participants
A total of twenty-six participants from throughout the United States were
involved in the evaluation workshop. These participants were selected to
serve on the specific panel which considered their individual areas of
professional expertise.
— Criteria used in reaching extensiveness of use and intensiveness of
effect ratings are shown in Exhibit IV-2. Note is made of the sixth
criterion for intensiveness ratings: yields, production, and associ-
ated effects. While the other criteria deal with direct and indirect
environmental implications, this criterion deals with productivity, (an
indirect environmental effect given a specified demand level) and caused
some concern within the panels when incorporating this into intensive-
ness values. Consequently improper emphasis may have been given to
this criterion when assessing trends (subtrends) dealing directly with
"practices," but this criterion was important when evaluating the in-
tensiveness that many "development" subtrends would have on the environ-
ment in 2010. However, since panels were allowed to adjust their ratings
(R) to reflect value judgements, this allowed for the desired perspective
for intensiveness ratings.
36
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All geographic regions of the U.S., and many disciplines within agri-
culture, silviculture and environmental science were represented by
the participants. Also, representatives of government (federal and
state), universities (including extension) and private industry were
involved. Naturally, the workshop as a whole was more broadly represen-
tative than were individual panels. An effort was made within the size
constraints of the workshop, to provide adequate expertise on each panel
to effectively complete the evaluations. However, for example, the
Irrigated Crop Production Panel did not have a pesticide expert; and,
consequently, they did not evaluate the pest control trends, per se
(the panel basically referred this assessment to the Nonirrigated Crop
Production Panel—which did have pesticide and pest control expertise).
Aside from this type of specific limitation, the panels were generally
balanced across disciplines needed for the assessment.
Each panel's participants are identified below in the panel summary
discussions.
37
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SECTION V
THE LEADING ENVIRONMENTALLY-RELATED TRENDS:
AGRICULTURE AND SILVICULTURE
This brief section is intended only to offer the reader a generalized
ranking of each agricultural and silvicultural panel's leading environ-
mentally-related trends in the major sectors considered in this study.
The trends are not considered at length at this point. Such discussions
are considered in Sections VI-X which are devoted to the five panel areas.
The present discussion is but an introductory overview partially indica-
tive of the findings of each panel.
An important aspect of this study's assessment of the environmental im-
plications of trends in agriculture and silviculture is the "level-of-
aggregation" of the study. In reality, the sources of residuals (and
pollutants) in the environment are usually individual production manage-
ment practices throughout the agriculture and silviculture sectors. How-
ever, it was not feasible to consider all specific management practices
within each segment of agriculture and silviculture in this study.
The approach of this assessment involved, first, the subdivision of these
sectors into five distinct production systems; and, second, the partitioning
of management practices and developments within each production system into
major groupings. Thirdly, key management practices and developments within
each management grouping were delineated and described. Finally, available
environmentally-related information (mostly qualitative at this time) was
included for each of the selected key trends and developments.
As discussed in Section IV, each of the panels examined the preliminary
study done by DPRA and its own subject area. Each panel then submitted
its area's five trends for general review and discussion. These leading
panel trends are summarized in Exhibit V-l.
The major trends and developments within each panel area are quite diversi-
fied and often unique to a specific panel area. Consequently, Development
Planning and Research Associates believed that each panel area required
focused attention if the major environmentally related trends of agri-
culture and silviculture were to be comprehensively understood.
Also shown in Exhibit V-l are each panel's "adjusted ratings" of the
relative environmental significance of each trend within the respective
panel areas (scores ranging from 1 to 25 were possible as explained in
38
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Exhibit V-l. Summary of panel and workshop rankings of major trends in agriculture and silviculture, 1976-2010
CO
10
1.
2.
3.
4.
5.
Panel
Nonirrigated Crop
Production
Irrigated Crop
Production
Feedlot Production
Range & Pasture
Management
Silviculture and \l
Harvest Management
Initial Panel
Trend Rank Of To,
No. £' Trend Five Trends
(104) Runoff & Erosion Control
(119) Improvement of Seeds & Plants (103 + 114)
(101) Conservation Tillage
(120) Scouting & Integrated Controls (112 + 117)
(121) Developing New Biological and Chemical
Pesticides (115 + 116)
(208) Improving Water Application
(204) Runoff & Erosion Control
(211) Methods of Nutrient Application
(220) Developing Integrated Controls
(210) Using Plant & Soil Analysis
(308) Feedlot Size
(319) Feedlot Design for Waste Management (306 + 311 *• 312)
(317) Residual Disposal (312 + 315)
(313) Odor Control
(318) Feed Efficiency & Ration (302 + 305)
(406) Grazing Practices: Range & Pasture
(405) Stocking Ranges
(401) Range & Pasture Renovation
(416) Using Increased Resources (411 + 415)
(417) Range & Pasture Improvement (402 + 404 + 407)
(502) Access to Timber Resource (Woods)
(505). Site Preparation
(503) Log Extraction
(504) Utilization (Logs & Residues)
(510) Fire Control
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
Panel
Adjusted
Rating (AR)
18
16
14
13
12
22
18
15
12
9
15
12
10
9
8
8
7
6
5
5
4
4
3
2
2
Final Work-
shop Rank
of Trends
1
5
2
6
7
3
4
11
14
16
9
8
10
17
19
12
13
15
18
20
iy Silviculture trends were rated by the silviculture panel only and were not Included in overall workshop rankings.
-J The number reflects those trend numbers used in Phase I- Interim Report
-------
Section IV, above). These ratings are not strictly comparable across
panels, for each panel evaluated its trends independently.
Furthermore, extreme care must be emphasized when interpretations of,
or conclusions about the trend ratings are made. First of all, the
environmental trend ratings are numerical scores which quantify the
opinions of selected professional agriculturalists who have specific
knowledge about their panel areas. The most important distinction which
must be recognized by environmentalists, agriculturalists, and any others
who may desire to interpret these environmental ratings is that these
ratings indicate only how important certain trends in agriculture and
silviculture will be, in regards to improving or degrading the environ-
ment. The ratings only indicate how a certain practice can potentially
change an environment from its current status.
In an attempt to clarify the distinction between trend ratings and en-
vironmental problems, the following example was constructed. If a par-
ticular trend had a rating of +20, this rating implies that the trend
would be expected to improve the environment in a relatively important
manner. The rating (+20) does not mean that the particular trend will
eliminate environmental problems; rather it merely means that the trend
is a relatively important activity which is expected to preserve (or
improve) an environment's quality. It also does not imply that an en-
vironment is currently "good" or "bad".
Notwithstanding the individual panel's results, the workshop did continue
to evaluate the relative importance of the top five trends from each panel.
In the end, only the agriculture trends were cross-ranked, i.e., from 1
to 20, representing the four agricultural panels. It was determined
that cross-ranking of trends in silviculture with those of agriculture
was not feasible because of difficulties in comparing the two. Silvi-
culture involves management over a long growth cycle, e.g., 30 to 60
years or more while agriculture comprises relatively intense management
on an annual basis. Consequently, silviculture trends were listed
separately. Ideally, much more quantitative information of environ-
mental effects should be gathered before explicit rankings of trends are
made. The workshop generally agreed that the Silviculture and Harvest
Management trends would most likely rank in the lower half of the major
twenty-five trends. This judgement was secondary, however, to the desire
and concern of the workshop—especially the Silviculture Panel, to first
recognize fundamental differences between agriculture and silviculture.
The data upon which each panel's judgements were made were those provided
by DPRA in its economic scenario projections, the agricultural and silvi-
cultural practices and input trend data compiled by DPRA and included in
subsequent panel-area sections of the present study, and the individual
knowledge and expertise of the panel participants.
The results of the overall ranking of the agriculture trends are discussed
below in Section XI following the summarization of each panel's trends and
ratings. For summary purposes, however, the final rankings of each panels
trends are also shown in Exhibit V-l, but without further explanation here.
40
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SECTION VI
ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVICULTURAL TRENDS:
PANEL 1 - NONIRRIGATED CROP PRODUCTION
The primary purpose of the Nonirrigated Crop Production Panel, as with
other subsector panels, was to assess and rank-order the major environ-
mentally related trends in its own area of expertise. The Panel 1 trends
assessed, and their rankings, are as shown in Exhibit VI-1. Brief des-
criptions of the ten most significant trends are presented in Exhibit
VI-2 (and in greater detail in subsection C, below). Additionally, the
panel members assessed both the extensiveness of use and the intensive-
ness of environmental effects of each trend or practice, which are sum-
marized in Exhibit VI-3; and, therefrom, the rankings were derived.
The Nonirrigated Crop Production Panel was the largest in the workshop
and included the eight members listed below. The panelists represented
a broad area of expertise: agronomy, pesticides, economics, fertilizers,
erosion, management systems, and soil erosion and runoff. The chairman
of the panel was George Browning, Regional Director of State Agriculture
Experiment Stations, Iowa State University.
Name
George Browning
W. L. Colville
Velmar Davis
Victor Kilmer
R. L. Leonard
Gary Margheim
Walt Wischmeier
Pierre Crosson
Representing
USDA-CSRS
University of Geo.
USDA-ERS
TVA
USDA-ARS
USDA-SCS
Consultant
RFF
Specialty
Management systems
Crop production
Economics
Fertilizer
Pesticides
Erosion
Erosion
Economics
Location
Ames, Iowa
Athens, Georgia
Washington, D.C.
Muscle Shoals, Ala.
Athens, Georgia
Washington, D.C.
West Lafayette, Ind.
Washington, D. C.
A. Major Trend Rankings and Practices Assessments
As discussed previously (Section IV, "Workshop Procedures") the procedure
used by the panel in assessing trends involved an analysis of the extensive-
ness (E) and intensiveness of effect (I) of each of the subtrends. The
product of these two ratings gave a significance rating for the subtrend.
Based on an examination of the ratings of all of the subtrends, a composite
rating was assigned to each major trend. The final step in ranking the
trends was an evaluation of all of the trends and a subsequent adjustment
41
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of the ratings in order to reflect a proper weighting among the trends
(Exhibit VI-1). In this step, six ratings were adjusted with the greatest
adjustment being made in the rating of Runoff and Erosion Control (104).
This trend was initially assigned a rating (R) of nine. After the panel
considered the impact of this trend in light of the impact of all other
trends, it doubled the rating to eighteen.
Exhibit VI-1. Ranking of environmentally-related trends, 1976-2010:
Nonirrigated Crop Production
Panel
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Trend
Number
(104)
(119)
(101)
(120)
(121)
(107)
(108)
(106)
(110)
(113)
(111)
(102)
(105)
(109)
(118)
Adjusted
Trend I/ Rating
Runoff & erosion control
Improvement of seed and plants
Conservation tillage
Using scouting & integrated controls
Developing new biological & chemical pesticides
Improving soil -plant analysis
Methods of nutrient applying
Wind erosion control
Developing nitrogen-fixation sources
Improving pesticide application methods and
timing
Developing improved fertilizer
Crop sequencing
Moisture conserving
Alternative nutrient sources
Using increasing rates and amounts of crop
production inputs
18
16
14
13
12
10
8
8
8
7
6
4
2
2
1
II The panel specifically ranked the top ten trends as shown. Trends 11-15
were ranked by DPRA according to the intensiveness and extensiveness
ratings associated by the panel.
42
-------
ExhTbU Vl-2. Description of major environmentally-related trends, 1976-2010: NonirHgated Crop Production
Panel
Rank
Trend Number and Title
Adjusted Rating
for 2010
Comments and ,iodifications
CO
10
(104) Runoff and Erosion Control
(119) Improvement of Seed and Plants
(101) Conservation Tillage
(120) Using Scouting and Integrated
Controls
(121) Developing New Biological and
Chemical Pesticides
(107) Improving Soil-Plant Analysis
(108) Methods of Nutrient Applying
(106) Wind Erosion Control
(110) Developing Nitrogen-Fixation
Sources
(113) Improving Pesticide Application
Methods and Timing
18
16
14
13
12
10
Runoff and erosion control measures stabilize the soil im-
peding sediment movement and nutrient and pesticide runoff.
The primary effect of these measures will be the reduction
of water and land pollution; the recondary effect will be
the increase of moisture retained in the soil and percolated.
These improvements include increases in production effi-
ciency and increases in resistance to weather, insects,
disease and other pests. These increases are expected to
Increase crop yields and decrease the overall requirements
for pesticides.
Conservation tillage includes no-till and other practices
involving a reduction in tillage over conventional systems.
The increasing utilization of these practices will have
major effects on water and soil quality by the reduction
of runoff and soil movement.
Scouting, which involves both surface means and remote
sensing, is expected to reduce the overall pesticide use by
reducing requirements for continued application in areas
having no threat of pest infestation. Integration of bio-
loqical, chemical, and mechanical methods will increase the
efficiency of pest control and decrease the overall pesticide
requirements.
Developments in new pesticide formulations and biological
controls are expected to increase the efficiency of pest
control.
New soil-plant analysis techniques for analyzing nutrient re-
quirements are being developed which are expected to receive
widespread application and will benefit both crop yield and
the environment.
Methods are being developed and utilized which increases the
efficiency of commercial fertilizer application. Generally,
these methods have beneficial effects by increasing crop
yield and reducing fertilizer runoff.
The co'.trol measures, which include strip-cropping, barrier
rows, and tree windbreaks, stabilize the soil and impede
sediment movement.
Developments in biological nitrogen-fixation, both in legumes
and non-legumes, are expected to significantly decrease com-
mercial fertilizer use.
Improvements 1n methods of applying pesticides, such as dual
application and improved placement, are occurring which will
improve the efficiency of pesticide use and reduce the poten-
tial for pesticide runoff.
-------
Exhibit VI-3.
Environmental ratings of top ten trends and associated
practices: Ncnirrigated Production
Panel
Rank
1
2
3
4
5
6
7
8
9
10
Trend
Number
(104)
(119)
(101)
(120)
(121)
(107)
'(IDS)
(106)
(110)
(113)
Extensiveness Intensiveness
Trend Rating Rating
Trend and Subtrcnd
Runoff & Erosion Control
a. Contour farming or contour strip-
cropping
b. Terraces and grass waterw?vs
c. Optimizing time of operations
d. Narrow rows
Improvement of Seed and Plants
a. Weather resistance
b. Salt resistance
c. Production efficiency
d. Disease rosistan: crtips
e. Insect & nematode resistant crops
Conservation Tillage
a. No-tillage
b. Reduced tillage
Using Scouting and Integrated Controls
a. Surface scouting
b. Remote sensing scouting
c. Using integrated controls
Developing New Ciological and Chemical
Pesticides
a. Micro-encapsulated pesticides
b. Systemic pesticides
c. Surfactants for herbicides
d. Bio-degradable pesticides
e. Alternat've formulations
f. Juvenile hormones
g. Pheromones
h. Sterile males
1. Predator and parasites
Improving Soil-Plant Analysis
Methods of Nutrient Applying
a . roTTar fertilization
b. Multiple applications
c. Fall application
d. Liquid fertilizers
e. Aerial and float--r application
f. Improver' nutrient placement
Wind Erosion Control
a. Strip-cropping
b. Barrier row
c. Windbreaks
Developinq Nitrogen-Fixation Sources
a. Legume sources
b. Non-legume sources
Improving Pesticide Application
Methods and Timing
a. Improving aerial application
b. Improving floater application
C. Fertilizer and pesticide dual
application
d. Improving pesticide placement
1976
3
4
3
3
4
1
4
5
3
1
3
1
1
2
1
2
1
3
3
1
1
1
1
3
1
3
3
3
1
4
2
1
1
2
1
3
1
3
2
1935
4
5
4
4
4
1
4
5
4
1
4
3
1
3
2
3
2
4
4
2
2
1
1
4
2
3
3
4
1
4
2
1
1
3
1
4
1
4
3
2010
5
5
4
5
5
1
5
5
5
2
5
5
2
4
3
4
3
5
5
4
4
2
1
9
2
4
4
5
2
4
3
3
2
4
3
4
2
4
4
2010
+4
+4
+4
+3
+2
+2
+3
+3
43
44
43
44
41
44
42
43
42
44
42
43
43
44
42
43
41
42
-2
41
-1
43
43
43
43
42
43
41
41
41
43
44
-------
B. Environmental Implications of Major Trends
and Practices
The workshop findings for each major trend are summarized below. Back-
ground descriptions and definitions of each of these major trends and
the associated practices (or subtrends) are included in Part C: "Back-
ground Summary."
Runoff and Erosion Control (104). The panel rated this trend as the most
significant environmentally rated trend based on the environmental impli-
cations expected from the individual subtrends which included contour
farming, terracing, optimizing time of operations, and the use of narrow
rows. Of these subtrends, contour farming and terracing were considered
to have the greatest potential implications. The former subtrend received
a 1976 extensiveness rating of moderate, while the latter received a
rating of important. The extensiveness of both were expected to increase
to a major level by 2010. The intensiveness of each was expected to be
important (beneficial) by 2010. The panel observed that the trend in the
use of narrow rows was increasing rapidly. Its 1976 extensiveness
rating was moderate; however, this was expected to increase to a major
level by 2010. The environmental implications were considered to be
overall beneficial with a moderate rating. In extensiveness, optimizing
time of operations received a moderate rating for 1976; it was expected
to become important by 2010. In intensiveness, this subtrend was expected
to have an important beneficial effect by 2010.
Improvement and Seed Plants (119). This trend was developed by the panel
by combining two separate trends contained in the preliminary report (Seed/
Plant Improving (103) and Developing Resistant Crops (114). */ In this trend
the panel found difficulty in defining the research interaction between
subtrends, though it did conclude that this major trend could have as
much economic potential as any of the trends examined, particularly so
in the case of developing disease resistant crops. The intensiveness
of all of the subtrends was expected to be beneficial. The most exten-
sive subtrend was considered by the panel to be the development of disease
resistant crops. Its extensiveness in 1976 was considered to be major
and was expected to continue so to 2010. The trends in production ef-
ficiency were considered to increase from a 1976 rating important to a
level of major impo-tance by 2010. Trends in insect and nematode re-
sistant crops were expected to increase from moderate to major importance
by 2010. All three of the above subtrends were expected to have a moder-
ate intensiveness by 2010. The intensiveness of the remaining two trends,
weather resistance and salt resistance, were expected to result in only
limited benefits to the environment. In extensiveness, improvements
in weather resistance were expected to be major in 2010; improvements
in salt resistance were expected to be minor through 2010.
-f See Part C: "Background Summary" for details of original trend
descriptions.
45
-------
Conservation tillage (101). No tillage and reduced tillage were expected
to have significant environment implications because of their reduction
of soil movement and run-off. However, the panel expressed the concern
that the required increase in pesticide and fertilizer application
would have adverse effects. Because of the increased fertilization and
reduced run-off, the nitrate content of the groundwater could be expected
to increase. Although the practice of reduced tillage and no-till both
were considered to have substantial implications, beneficial on the
environment , moderate intensiveness for reduced tillage and important
for no-tillage), the expected extensiveness varied considerably between
the two. The 1976 extensiveness was rated as minor for no tillage and
was expected to be only limited by 2010. On the other hand, the exten-
siveness of reduced tillage in 1976 was considered to be moderate and
was expected to increase to major by 2010.
Using Scouting and Integrated Controls (120). This trend represents a
combination of two separate trends contained in the preliminary report
(Using Scouting (112) and Developing Integrated Controls (117). The
trend was expected to have significant beneficial implications for the
environment because of its resultant overall reduction in pesticide use.
The subtrends include surface scouting, remote sensing scouting, and
integrated controls use. Remote sensing was expected to have the least
environmental implication both in extensiveness and intensiveness. Its
extensiveness was rated as minor for 1976 and was not expected to increase
significantly, becoming of only limited importance by 2010. Its inten-
siveness implication was considered by the panel to be minor. On the
other hand, the intensiveness of both of the other subtrends was rated
as major. Surface sensing was considered to have only a minor extensive-
ness in 1976 but a major extensiveness by 2010. Using integrated controls
was rated limited in extensiveness for 1976 but was expected to increase
to important by 2010.
Developing New Biological and Chemical Pesticides (121). This trend was
developed by the panel by integrating two separate trends contained in
the preliminary report, Developing New Pesticides (115) and Developing Bio-
logical Controls (116). The panel felt that all of the subtrends in-
volving both chemical and biological pesticides would have overall bene-
ficial implications. According to the panel, biological controls can
generally be expected to replace chemical pesticides if anticipated
breakthroughs occur. However, the panel felt the extensiveness of
the subtrends associated with chemical pesticides would be somewhat
greater than those with biological controls. The subtrends with the
greatest extensiveness (major) were the development of biodegradable
pesticides and use of alternative formulations; both were rated as
moderate for 1976 and were expected to be major by 2010. In intensive-
ness, the environmental implications .of the use of bio-degradable pesti-
cides was the greatest, receiving a rating of important while that of the
use of alternative formulations received a rating of limited. The panel
felt that, assuming breakthroughs, the use of juvenile hormones and
pheromones would become the most widespread of biological controls.
Although both were rated as minor in extensiveness for 1976, they
received a rating of important for 2010. The intensiveness for both
46
-------
trends was moderate. The use of sterile males received the highest
rating in intensiveness (major) but was considered to have only limited
application (receiving an extensiveness rating of only limited for
2010).
Improving Soil-PIant Analysis (107). New techniques have been developed
and are expected to be further developed to increase the efficiency of
fertilization. The benefits from the use of these techniques are an
increase in crop yield and a decrease in fertilizer runoff. The trend
was considered to be moderate (in extensiveness) for 1976, but it was
expected to be major by 2010. The beneficial implications of the expected
use of these techniques received an intensiveness rating of moderate.
Methods of Nutrient Applying (108). This major trend includes a number
of subtrends to increase the efficiency on the economics of appli-
cation. Most of these trends were considered by the panel to have overall
beneficial implications; however, two of them received adverse ratings:
fall application and aerial and floater application. The panel felt that
fall application increases the potential for runoff and, consequently,
assigned it an adverse rating of limited. The extensiveness of this sub-
trend was rated moderate for 1976 and was expected to increase somewhat
by 2010. Application by floaters and aircraft was rated at minor exten-
siveness for 1976; it would increase to only a limited rating by 2010.
In intensiveness, the adverse implications of this subtrend were considered
to be minor. The subtrend with the greatest implication (beneficial)
major in intensiveness, was designated by the panel as that of improved
nutrient application. Its extensiveness was rated at important for 1976
and was expected to remain at that level through 2010. The subtrend
having the greatest application was the use of liquid fertilizer. It
received a rating in extensiveness of major. Its environmental impli-
cation, however, was rated as only minor in intensiveness.
Wind Erosion Control (106). Practices included in this trend are strip
cropping, barrier rows, and windbreaks, all of which have beneficial
effects by stabilizing the soil and impeding sediment movement. All of
the practices were considered to have about the same environmental impli-
cation by the panel and received a rating in intensiveness of moderate.
Strip cropping and barrier rows were expected to have the same application
in 2010, receiving a rating of moderate in extensiveness. Wind breaks
were expected to have only limited use in 2010.
Developing Nitrogen-Fixation Sources (110). Considerable research is
going forward in this area and, according to the panel, much more needs
to be done. Nitrogen-fixation would benefit the environment by a reduc-
tion in the application of commercial fertilizers resulting in less nutrient
runoff. Fixation in non-legumes offers the greatest potential for re-
ducing fertilizer use; however, much research is required before any sig-
nificant breakthrough can be expected. Consequently, the panel rated the
extensiveness of this subtrend as minor for 1976 and moderate in 2010.
Its intensiveness received a moderate rating. Fixation in legume sources
was considered to be of limited extensiveness for 1976 and was expected
to increase only slightly by 2010. The intensiveness of this subtrend
was rated as only limited.
47
-------
Improving Pesticide Application (113). This trend was rated as tenth in
importance by the panel. Subtrends include improved application of
pesticides by aircraft and floaters, dual application of fertilizer
and pesticides, and pesticide placement improvement. The environmental
implications in terms of their intensiveness, of all of these subtrends
were considered by the panel to be beneficial. Improving placement was
considered to have the most extensive application (limited for 1976 and
important by 2010) as well as the highest rating in intensiveness (moderate),
The trend rated lowest in extensiveness was the improving of floater appli-
cation. Considered to have a minor rating for 1976, it would become only
limited for 2010. The remaining subtrends received moderate to important
ratings in extensiveness; however, in each case, the intensiveness was
rated as minor.
Other Trends. Trends ranked 11 to 15 in Exhibit VI-1 received relatively
low adjusted rankings from the panel, except for that of Developing Im-
proved Fertilizers (111). This trend received a rating nearly equal to
that for the tenth trend (Improving Pesticide Application). Using Increased
Rates and Amounts of Inputs (118) was considered to be of only minor im-
portance by the panel. This consideration was based on the assumption
that inputs would be optimized and that applications would be adequate.
The individual subtrends were both adverse and beneficial and when taken
in light of each other, their overall implications were expected to be
minor.
C. Background Summary
The following descriptions and definitions of the trends and management
practices related to nonirrigated crop production were provided to the
workshop participants as background for the workshop evaluation. In
some cases, the workshop panel chose to re-group selected subtrends into
new groups or to add/delete subtrends as noted. As such, this summary
is quasi-independent of the workshop results as presented in parts A and
B, above; but it provides appropriate background base data, definitions
and descriptions of the trends and practices assessed in this study.
1. Overview and Base Data
During 1972-74, about 276 million acres of harvested cropland, or
close to 90 percent of the total U.S. harvested cronland, were classi-
fied as nonirrigated. Exhibit VI-4 shows nonirrigated cropland har-
vested as a percent of total cropland harvested within each state by
the 1969 Census of Agriculture. Essentially all, or 98 percent of the
cropland in the thirty Eastern states were classified as nonirrigated.
The only significant irrigation of cropland within these states occurred
in Florida and Arkansas which irrigated 46 and 15 percent of their crop-
land respectively.
48
-------
Exhibit VI-4. Nonirrigated cropland as a percent of total cropland harvested: 1969
Alaska — 93%
Hawaii — 60%
91X
-------
In the seventeen Western states and Louisiana, slightly over 75 percent
of the cropland harvested was nonirrigated. Neither Nevada nor Arizona
had significant amounts of nonirrigated cropland. Nonirrigated cropland
in California amounted to less than 20 percent of the total. Utah, Idaho,
Wyoming and New Mexico had less than 50 percent.
The total nonirrigated cropland harvested is projected to increase to
280 million acres in 1985 and to 318 by 2010. The major increases are
expected to occur in Minnesota and in the Corn Belt states. Slight
decreases are expected to occur in many Eastern seaboard and Northwest
states.
Crop production on nonirrigated land contributes, in various degrees,
to the pollution of water, air and land. Additionally it may result
in other environmental damages to ecology .aesthetics and human health.
Its major environmental effects are to surface water and to soil erosion.
Although it may cause significant other environmental problems in local
areas, such problems are nationally inconsequential.
The major nonirrigated cropland pollutants affecting surface water include
sediment, pesticides, fertilizer, plus pollutants arising from animal waste,
municipal waste and crop residue. They are transported to surface water
bodies through direct runoff, sediment movement, and percolation. Sediment
movement in addition to transporting pollutants to surface water also con-
stitutes soil erosion, by far the major cause of land pollution.
On the basis of volume, soil erosion sediment is the chief pollutant
and it is measured by estimating the average annual rates of soil
movement from cropland. Erosion losses from cropland vary from
negligible to more than 100 tons per acre. On both irrigated and
nonirrigated cropland, an average loss of 8 tons of soil per acre is
estimated to occur on 20 percent of the land, between 3 and 8 tons on
50 percent of the land, and fewer than 3 tons on the remaining 30
percent.
Although actual erosion rates have not been mapped on a national
scale, the relative potential cropland erosion problems have been
estimated as illustrated in Exhibit VI-5. Very high erosion rates
are estimated to occur in the Corn Belt and in the western parts of
Tennessee and Kentucky. High rates occur in most of the remaining
portions of the North Central Region. Low rates generally occur in
the Eastern seaboard states, throughout Florida, and along the Gulf
Coast.
Estimates made by Holeman (ASCE, 1970) show the annual erosion rates
in the contiguous United States at 4 billion tons with about half
of this reaching waterways. In recent estimates made by EPA, the
annual sediment loading from all cropland was determined to be 1.9
billion tons. Since the major portion of sediment yield comes from
nonirrigated harvested cropland, that agricultural land contributes
50
-------
Exhibit VI-5. Relative potential contribution of cropland to watershed sediment yields
Low
Moderate
High
Very High
-------
over 50 percent of the nation's total sediment yield to surface
waters.
Although sediment is the chief pollutant by volume, fertilizer and
pesticides have attracted the greatest public concern. Pollution
problems from fertilizers may be expected to occur in those areas
in which large numbers of acres receive high rates of application.
Exhibit VI-6 shows the location of the major (mostly nonirrigated)
cropland harvested for the four most significant crops in terms of
total production (corn, soybeans, cotton and wheat). The greatest
corn cropland acreage is in the Corn Belt. Most nonirrigated cotton
cropland is located along the southern part of the Mississippi River.
Nonirrigated soybean cropland is concentrated along the Mississippi
River with cotton and in the Corn Belt with corn. Exhibit VI-7 lists
the total acres of these crops harvested (1974) and their respective
average fertilizer application rates. Corn shows the most acres
harvested and the highest application rates. Cotton, the crop with
the lowest total acreage harvested, shows the second greatest appli-
cation rate. The data in the above exhibits indicate those areas
having the major potential pollution problems from fertilizers.
Commercial fertilizers contain the plant nutrients nitrogen (N), phos-
phorus (P) and potassium (K). Since no evidence suggests that K poses
any significant problem in water pollution, the only nutrients having
environmental implications are N and P. These two nutrients are trans-
ported to surface waters largely by two means: nitrogen, relatively
soluble, reaches the surface waters via runoff and percolation; phosphorus,
relatively insoluble, is attached to sediment and enters the water through
sediment movement. Exhibit VI-7 shows the amounts of these nutrients
which were applied to the four major crops.
Although commercial fertilizer is the major source of cropland applied
nitrogen, supplying over 9 million tons annually, animal wastes (manure)
are a significnat source of over 1 million tons. Animal waste can pose
more significant local N and P pollution problems than commercial fer-
tilizer when high per acre rates are applied. Since manure is disposed
of on cropland in the vicinity of the feedlots in which it was produced,
the greater threat of pollution will be concentrated in the major live-
stock producing areas. Beef feedlots and dairy farms each produce over
300 thousand tons of nitrogen annually. The greatest concentration of
beef feedlots disposing of wastes on nonirrigated cropland is found in
Nebraska and Iowa. Dairy farms are concentrated rather uniformly through-
out the Lake states and the Northeast Farm Production Regions. Hog
feedlots produce a total of 300 thousand tons of nitrogen annually and
are concentrated in the Corn Belt. Poultry production, yielding 125
thousand tons of nitrogen annually, is concentrated in the Southeast.
Pesticide pollutants, while minor in terms of total volume, have created
great concern because of the toxicity and persistence of some. Little
national data exist on pesticide loading from cropland in surface waters.
The most recent national survey of agricultural pesticide use was made
in 1971, and it showed that a total of 466 million tons was used on
52
-------
Exhibit VI-6. Location of cropland - corn, soybeans, cotton, wheat.
v\
si
Wheat
Corn
Soybeans
Cotton
-------
cropland (irrigated and nonirrigated). Sales data estimate that the
total increased by close to 70 percent in 1975 with much of the in-
crease attributed to the growing use of conservation tillages which
require higher application rates of herbidices. Exhibit VI-8 shows
the acreage of crops treated with herbicides and insecticides in 1969,
and it is assumed to reflect current usage. Close to 80 percent of all
crop pesticides is applied to the four major crops: corn, wheat, cotton,
and soybeans; consequently, as illustrated in the exhibit, the major
potential pollution of nonirrigated cropland from pesticides is concen-
trated in those crops' major growing areas. No estimate has been made
of the total amount of pesticides entering the nation's streams and
rivers; however, many investigations have been made of runoff in local
areas. These limited studies suggest that pesticide runoff from crop-
land is less than 5 percent of the applied amounts. (Caution: Concen-
tration of pesticides, not percent of run-off, produces environmental
effects of concern.)
Exhibit VI-7. Acres receiving fertilizer and average fertilizer rates
of four crops in the United States, 1974
Percent fertilized
Crop
Corn
Cotton
Soybeans
Wheat
Acres harvested
63.7
13.1
52.5
64.1
N
94
79
22
66
P
87
58
28
46
Pounds/acre rate
N
103
78
15
46
P
27
23
18
17
Source: U. S. Department of Agriculture/U.S. Environmental Protection
Agency, Control of Water Pollution from Cropland, Report No.
ARS-H-5-1, Wash. D. C., 1975.
54
-------
Exhibit VI-8. Croplands treated with pesticides
and herbicides: 1969
Acreage of non-hay crops treated with insecticides
Acreage of crops treated with herbicides
Source: Control of Water Pollution from Cropland. Volume I.
USDA, EPA. 1975.
55
-------
2. Trends and Environmental Implications -
Crop production on nonirrigated cropland encompasses a wide variety of
management practices which differ considerably among crops and among
geographical regions. Although the entire production system must be
viewed to assess the total impact of this cropland on the environment,
each of the practices can be examined to determine its specific environ-
mental implications.
Trends. The general relationships of these management practices within
the production system are illustrated in Exhibit VI-9. Included in the
system are the management practices (resource management), resource in-
puts, technological developments, and the production outputs (including
residuals generated). This system provided the framework in which the
trends in crop production on nonirrigated cropland were identified. Those
trends discussed and analyzed are listed in Exhibit VI-10 and subsequently
described in Exhibit VI-11. The specific trends have been grouped under
the following major practices: (1) crop management, (2) soil-water manage-
ment, (3) nutrient management, and (4) pest control. The trends, expressed
in brief terms, implicitly reflect the adoption or the increasing utiliza-
tion of the specific management practice.
Environmental Implications. In the Contractor's preliminary analysis of
the trends, a matrix (Exhibit VI-12) was developed so that the potential
interactions between the specific practices and the generation of pollu-
tants could be examined. These interactions represent changes that would
occur in the amount of pollutants produced on a representative unit of
production (acre of nonirrigated cropland) if it were cropped under conven-
tional practice and conditions prevalent in 1976. The interactions were
denoted by pluses (+) and minuses (-) (+ represents a decreasing effect
or beneficial environmental impact; - denotes an adverse environmental
impact). The matrix not only illustrates the interactions between specific
practices and pollutants generated, but also represents, in certain cases,
logical interactions among practices. For example, the primary impact
of no-till planting is a decrease in soil sediment; however, no-till re-
quires an attendant increase in the use of pesticides. Consequently, this
increase is reflected in the matrix as an interaction between the practice
of no-till and the generation of pesticide pollutants. Based on a review
of the interactions displayed in the matrix, general conclusions were drawn
about the trends and environmental implications.
— Though not of substantive concern affecting the trend rankings and prac-
tice assessments arrived at in this study, major trend categories dis-
cussed in these base data were in some cases regrouped by the workshop
panels to facilitate assessments. These changes are as follows for Panel
Base data category became Revised category
103, 114 119
112, 117 120
115, 116 121
56
-------
Exhibit VI-9. Crop production system: Nonirrigated Cropland
SCIENCE t
TECH.ttLOGY
RESOURCES
INPUT
RESOURCES
HWGEMENT
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IZATION
1
r
MECHAN-
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I LEVEL
4
f
TILLAGE
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,
SEEDS
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FERTILIZER
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_ ^
1
i
(>EST KARVESTINS
CO.NTROL
YIELD
OUTPUT
OUTPUT
\
YIELD
^
SEDIMENT
^
NUTRIENTS
X .
WASTE
WATER
1
INORGANIC
SALTS 1
MINERALS
f
t
PESTICIDES
4
BIODEGRAD-
ABLE
ORGAN I CS
4
CROPS
1
CROD
RESIDUE
57
-------
Exhibit VI-10. Environmentally-related trends: Nonirrigated Cropland
CROP MANAGEMENT TRENDS
101. CONSERVATION TILLING
a. No-tillage
b. Reduced tillage: chisel plowing, under-
cutting, chemical
102. CROP SEQUENCING
a. Mono-crop sequencing
b. No-meadow crop sequencing
c. Relay cropping
d. Double cropping
103. SEED/PLANT IMPROVING *J
(Genetic development)
a. Weather resistance
b. Salt tolerance
c. Production efficiency
SOIL WATER MANAGEMENT TRENDS
104. RUN-OFF AND EROSION CONTROLLING
a. Contour farming: contour planting,
contour-strip cropping
b. Using terraces and grass waterways
c. Using winter cover crops
d. Optimizing time of operations :
tillage, planting
e. Using narrow rows
f. Using chemical erosion-control agents
105. MOISTURE CONSERVING (STORAGE)
a. Fallow cropping: moisture storage,
salt-seeps
b. Using evapo-transpiration reducing
agents
106. WIND EROSION CONTROLLING
a. Using strip cropping (other than
contour-strip)
b. Using barrier rows (crops)
c. Using free windbreaks
58
-------
Exhibit VI-10 (continued)
NUTRIENT MANAGEMENT TRENDS
107. IMPROVING SOIL-PLANT ANALYSIS
(CROP LOGGING)
108. METHODS OF NUTRIENT APPLYING
a. Using foliar fertilization
b. Using multiple applications
c. Using fall application
d. Using liquid fertilizers
e. Using aerial and floater
application
f. Using improved nutrient
placement
109. USING ALTERNATIVE NUTRIENT SOURCES
a. Using animal wastes
b. Using municipal treatment plant
wastes
c. Using green manure crops
110. DEVELOPING BIOLOGICAL NITROGEN-FIXATION
SOURCES
a. Developing legume sources
b. Developing non-legume sources
111. DEVELOPING IMPROVED FERTILIZERS
a. Developing controlled-release
fertilizers
b. Developing high nitrogen content
fertilizers
c. Developing high phosphate content
fertilizers
PEST CONTROL TRENDS
112. USING SCOUTING *J
a. Using surface scouting
b. Using remote sensing scouting
113. IMPROVING PESTICIDE APPLICATION METHODS
AND TIMING
a. Improving aerial application
b. Improving floater vehicle application
c. Developing fertilizer and pesticide
dual application
d. Improving pesticide placement
59
-------
Exhibit VI-10 (continued)
114. DEVELOPING RESISTANT CROPS */
a. Developing disease resistant crops
b. Developing insect and nematode resistant crops
c. Developing bird resistant crops
115. DEVELOPING NEW PESTICIDES t!
a. Developing micro-encapsulated pesticides
b. Developing systemic pesticides
c. Developing surfactants for herbicides
d. Developing bio-degradable pesticides
e. Developing alternative formulations
116. DEVELOPING BIOLOGICAL CONTROLS */
a. Developing juvenile hormones
b. Developing pheromones
c. Developing sterile males
d. Developing predators and parasites
117. DEVELOPING INTEGRATED CONTROLS*/
(i.e., chemical-biological-mechanical)
RESOURCE USE TRENDS
118. USING INCREASED RATES AND AMOUNTS OF CROP
PRODUCTION INPUTS
a. Using commercial fertilizers
b. Using other nutrient sources: livestock
wastes, municipal sludges
c. Using chemical pesticides: herbicides,
insecticides, fungicides, rodenticides, etc.
d. Using energy: petroleum products, electricity,
sunlight
e. Using new cropland (including set-aside lands)
- See subsection C-2: Trends and Environmental Implications, for changes
in trend groupings by the evaluation workshop.
60
-------
Exhibit VI-11. Description of environmentally-related trends and
developments: Nonirrigated Cropland
CROP MANAGEMENT TRENDS
101. CONSERVATION TILLING - general reduction in cropland soil
disturbance
a. No till plant: seeding without pre-planting tillage
b. Reduced tillage: weed control and soil breaking
with limited soil inversion coupled with chemical
treatment
102. CROP SEQUENCING - cropping patterns
a. Mono-cropping: successive planting of one crop on
the same plot of land
b. No-meadow: eliminates pastures or meadows from
rotation sequence
c. Relay cropping: planting the second crop before the
first crop is harvested
d. Double cropping: planting the second crop after the
first crop is harvested in the same growing season
103. SEED/PLANT IMPROVING V
a. Weather resistance: plants genetically developed to
withstand winds, drought, etc.
b. Salt tolerance: developing plants capability to pro-
duce in a saline environment
c. Production efficiency: genetic development of plants
which utilize nutrients and sunlight more efficiently
and have desired growth characteristics of root De-
velopment, growth and maturity.
SOIL WATER MANAGEMENT TRENDS
104. RUNOFF AND EROSION CONTROLLING
a. Contour farming: farming operations are performed
according to the land evaluations
b. Terracing: soil embankments which slow the downhill
flow of surface waters
c. Cover crops: stubble mulching and grassed waterways
to slow runoff flew.
d. Optimizing time of operation: performing farm operations
to minimize the time period that the soil is bare
e. Narrow rows: reducing the distance between adjoining
rows of seeded crops
f. Chemical erosion-control: Chemical agents applied to
reduce soil erosion
61
-------
Exhibit VI-11 (continued)
105. MOISTURE CONSERVATION
a. Fallow - allowing the land to rest during one year
of cropping rotation to enhance moisture and nutrient
content
b. Evapo-Transpiration: agents used to reduce moisture
loss through leaf surfaces
106. WIND-EROSION CONTROLLING
a. Strip cropping: dividing the field in alternate
narrow bands of crop and fallow land
b. Barrier rows: use of taller crops to act as wind
breaks
c. Wind breaks: planting trees and shrubs to reduce the
effect of the wind and soil loss
NUTRIENT MANAGEMENT TRENDS
107. IMPROVING SOIL-PLANT ANALYSIS (crop logging) - monitoring
nutrient uptake, soil nutrients available, and plant condi-
tion to provide information to adjust fertilizer rates, timing,
and cultural practices
108. METHODS OF NUTRIENT APPLYING
a. Foliar fertilization: applying fertilizer as a spray
so that nutrients are taken up through the leaves of
the plant
b. Multiple application: fertilizer is applied more
than one time to realize optimum growth and crop
production
c. Fall fertilization: application of fertilizer dur-
ing the fall season prior to the crops primary grow-
ing season
d. Liquid fertilizer: application of nutrients as a
liquid to enhance crop production
e. Aerial and floater application: fertilizer is applied
via airplane, helicopter, or by ground machines equipped
to traverse wet and dry ground with limited soil com-
pactions
f. Improved nutrient placement: aerial, water, side band
broadcast application methods
USING ALTERNATIVE NUTRIENT SOURCES
a. Animal wastes: solid and liquid wastes from live-
stock feedlots contain nutrients and organic matter.
b. Municipal treatment plant wastes: use of municipal
wastes as a source of nutrients
c. Green manure crops: crops grown for the intended
purpose of incorporating immature plants into the
soil structure
62
-------
Exhibit VI-11 (continued)
110. DEVELOPING BIOLOGICAL NITROGEN-FIXATION SOURCES
a. Legumes: plants capable of fixing atmospheric nitrogen
and accumulating it in root nodules
b. Non-legume: soil microbacterial populations that are
able to fix nitrogen from the air.
111. DEVELOPING IMPROVED FERTILIZERS
a. Controlled-release: chemical inhibitors to delay nitri-
fication, leaching etc. are added to fertilizers
b. High nitrogen content: use ammonia to supply a high
concentration of nitrogen
c. High phosphorus content: use of polyphosphates to
increase phosphorus content about 50 percent more than
ordinary fertilizers
PEST CONTROL TRENDS
112. USING SCOUTING-/
a. Surface: determine types of pests and potential crop
damage by visual inspection
b. Remote sensing: insect populations and locations are
determined by satellite information
113. IMPROVING PESTICIDE APPLICATION METHODS AND TIMING
a. Aerial application: new methods to decrease pesticide
drift during application by increasing and homogeneous
partical size
b. Floater vehicle: can be used on wet soil for timely
application
c. Dual application: Herbicides, pesticides, and liquid
fertilizer simultaneous application
d. Pesticide placement: using the most effective and
efficient manner, for applying pesticides
114. DEVELOPING RESISTANT CROPS -/
a. Disease resistant: genetically developing plant species
capable of resisting specific diseases
b. Insect and nematode resistant: genetically developing
plant species capable of resisting selected insects and
nematodes
c. Bird resistant: genetically developing plant species
that are less accessible to feeding bird populations
63
-------
Exhibit VI-11 (continued)
DEVELOPING NEW PESTICIDES-/
a. Micro-encapsulated pesticides: pesticides in micro-
capsule form that slowly release the pesticide over a
longer time period
b. Systemic pesticides: pesticide compounds that are
absorbed by the plant which make it toxic to pests
c. Surfactants: chemical materials which enhance the
adsorption and absorbtion properties of herbicides
d. Bio-degradable pesticides: chemicals which are affective
against pests and are decomposable by the environment
with limited persistence.
e. Alternative formulations: different methods combining
chemicals which are effective against pests.
116. DEVELOPING BIOLOGICAL CONTROLS */
a. Juvenile hormones: Hormonal compounds capable of pre-
venting normal development and maturation of insects
b. Pheromones: chemical compounds containing organo-
phosphorus insecticide used to selectively attract
insects.
c. Sterile males: release sexual sterile insects to
decrease or control insect population
d. Predators and parasites: use of natural enemies,
fungi, virsuses, bacteria, to control insect populations
117. DEVELOPING INTEGRATED CONTROLS V-integrating chemical, bio-
logical, and mechanical treatment methods to achieve desired
control over cropland production
RESOURCE USE TRENDS
118. USING INCREASED RATES AND AMOUNTS OF CROP PRODUCTION
INPUTS - increasing demands for cropland production will
affect the quantity of fertilizer, animal and municipal wastes,
chemicals, energy and land used for food production
— See subsection C-2: Trends and Environmental Implications, for changes
in trend groupings by the evaluation workshop.
64
-------
Exhibit VI-12. Environmentally-related trends: Nonlrrigated Cropland
0\
tn
CROP
101
102
TDCMnC
MANAGEMENT TRENDS
. CONSERVATION TILLING
a. No-tillage
b. Reduced tillage: chisel
plowing, undercutting,
chemical
. CROP SEQUENCING
a. Mono-crop sequencing
b. No-meadow crop sequencing
c. Relay cropping
d. Double cropping
103. SEED/PLANT IMPROVING
SOIL
(Genetic development)
a. Weather resi stance.
b. Salt tolerance
c. Production efficiency
WATER MANAGEMENT TRENDS
104. RUN-OFF & EROSION CONTROLLING
105
a. Contour farming: contour
planting, contour-strip
cropping
b. Using terraces & grass waterways
c. Using winter cover crops
d. Optimizing time of operation:
tillage, planting
e. Using narrow rows
f. Using chemical erosi on-
ce ntrol agents
. MOISTLRE CONSERVING (STORAGE)
a. Fallow croooina: moisture
Surface Water
Inorganic
Sedl- NHro- Phos- Pestl- salt and
nent aen phorus ddcs minerals
+ + * 0
+ + + 0
+ + + - 0
0
0
o
+ + + T 0
+ + + •> 0
+ 0 + 0 0
+ 0 + 00
0000 0
+ + + 0 0
+ + + -- 0
+ + + + 0
+ + + + 0
+ + + + 0
+ + + + 0
+ + + + 0
+ + f + 0
0 - ^
o - +
Biode-
gradable
oraan1cs_
-
-
-
0
0
-
-
•
-
0
-
+
+
+
+
0
-
0
+
+
Grou
Nitrates
-
-
-
0
0
+
-
"*
0
0
0
"
-
-
-
-
+
+
-
.
.
nd liater
Pesti-
cides
-
-
-
-
-
~
-
"
0
0
0
0
-
-
-
-
+
+
-
+
•*•
Incrginic
sa'.t and
ml neral s
0
0
0
0
0
0
0
0
0
0
0
0
—
-
-
-
+
0
-
-
0
— AT?
Par-
ti cu-
Gases lares
0 +
0 +
0 +
0
0
0
0 +
0 +
0 +
0 +
0 0
0 +
0,
+
0 +
0 +
*
0 +
- +
0 +
+
+
Son Sa-
eroslon Unity
+ 0
+ 0
+ 0
0
0
0
+ 0
+ 0
+ 0
+ 0
0 0
+ 0
+ f\
0
+ 0
+ 0
+ 0
+ 0
. f\
+ 0
+ 0
-
- -
L.ir.a
Ke&vy
metals
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pesti-
cide
residues
*
-
-
-
~
~
~
0
0
0
0
•
~
*
+
+
-
0
0
Fiode-
orQanlcs
~
-
~
0
~
-
0
"•
~
~
0
-
-
storage, salt-seeps
b. Using evapo-transpiration
reducing agents
-------
Exhibit VI-12 (continued)
Surface Uater
Potc-irtfa1"_Cont"riiVjtion to PoT.uticr^-' c. Using fall application
C^ d. Using liquid fertilizers
e. Using aerial and floater application
f. Using improved nutrient
109. USING ALTERNATIVE NUTRIENT SOURCES
a. Using animal wastes
b. Using municipal treatment plant wastes
c. Using green manure crops
110. DEVELOPING BIOLOGICAL NITROGEN-FIXATION
SOURCES
a. Developing legume sources
b. Developing non-legurae sources
111. DEVELOPING IMPROVED FERTILIZERS
a. Developing controlled-release
fertilizers
b. Developing high nitrogen content
fertilizers
c. Developing high phosphate content
fertilizers
0
0
0
0
u
0
0
0
I
c
c
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
Exhibit VI-12 (continued)
O\
Potential Contrib
Surface Water
TRENDS
PEST CONTROL TRENDS
112.
113.
114.
115.
USING SCOUTING
a. Using surface scouting
b. Using remote sensing scouting
IMPROVING PESTICIDE APPLICATION
METHODS MO TIMING
a. Improving aerial application
b. Improving floater vehicle application
c. Developing fertilizer and pesticide
dual application
d. Improving pesticide placement
DEVELOPING RESISTANT CROPS
a. Developing disease resistant crops
b. Developing insect and nematode
resistant crops
c. Developing bird resistant crops
DEVELOPING NEW PESTICIDES
a. Developing micro-encapsulated
pesticides
b. Developing systemic pesticides
c. Developing surfactants for herbicides
d. Developing bio-degradable pesticides
e. Developing alternative formulations
Sed1-
0
0
0
+
0
•f
+
0
+
+
+
•f
0
0
0
0
0
0
nitro-
gen
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Phos-
phorus
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Inorganic
Pesd- salt and
cides minerals
+ 0
+ 0
+ 0
0
•r 0
+ 0
0 0
+ 0
+ 0
4- 0
+ 0
+ 0
+• 0
+ 0
+ 0
+ 0
+ 0
+• 0
Biode-
gradabl e
orqjMcs
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
ution to Pollution—Major
Ground Water
Nitrates
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Inorganic
Festt- salt and
cides minerals
+• 0
+• 0
+- 0
-i- 0
0 0
+ 0
0 0
+ 0
+ 0
+ 0
+ 0
+ 0
+• 0
+ 0
+ 0
+ 9
+ 0
+ 0
Pollutants
Air
Gases
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Par-
ti cu-
lates
0
0
0
+
0
+
0
0
+
+
+
•f
0
0
0
0
0
0
Soil
erosion
0
0
0
+
0
+
0
0
+
+
+
4-
0
0
0
0
0
0
Sa-
linity
0
0
0
0
0
0
0
0
c-
0
0
0
0
0
0
0
0
0
Ltr.i
Keavy
ratals
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pesti- Biode-
d£e gradaale
residues orcar.ics
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
0 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
-------
Exhibit VI-12 (continued)
oo
Potential Contribution tc Pollution — Major
Surface Water
116.
117.
RESOURCE
118.
TRENDS
DEVELOPING BIOLOGICAL CONTROLS
a. Developing juvenile hormones
b. Developing pheromones
c. Developing sterile males
d. Developing predators and parasites
DEVELOPING INTEGRATED CONTROLS
(i.e. , chemical-biological-mechanical)
USE TRENDS
USING INCREASED RATES AND AMOUNTS OF
CROP PRODUCTION INPUTS
a. Using conmercial fertilizers
b. Using other nutrient sources:
livestock wastes, municipal sludges
c. Using chemical pesticides: herbicides,
insecticides, fungicides, rodenticides
d. Using energy: petroleum products,
electricity, sunlight
e. Using new cropland (including set-
Sedi- Nitro-
ment gen
+ 0
+ 0
t- 0
+ 0
+ 0
0 0
.
_
-
0
0 0
Phos-
phorus
0
0
0
0
0
0
.
_
-
0
0
Inorganic
Pestl- salt and
cities minerals
+ 0
+ 0
+ 0
+ 0
+ r
+ 0
.
0 0
0 0
0
0 0
graddble
oreanics
0
0
0
0
0
0
_
-
-
0
0
Ground Uiter
Nitrates
0
0
0
0
0
0
.
-
-
0
0
Inorganic
Pestl- salt and
ddes minerals
+ 0
+ 0
+ 0
+ 0
+ 0
+ 0
_
0 0
0 0
0
0 0
Pollutants
Air
Gases
0
0
0
0
0
0
-
.
-
0
0
Par-
ticu- Soil Sa-
lates erosion Unity
+ + 0
+ + 0
+ + 0
+ + 0
+ + 0
000
_
p
0
0
000
Li-i
H;avy
totals
0
0
0
0
0
0
.
0
0
0
0
Pest-.- Eioc=-
dce gradaMe
residjes oroanics
+ 0
+
+ 0
+ 0
+ 0
+ 0
-
0
0
0
0 0
aside lands)
-------
(a) Crop management trends. The principal trends projected in crop
management involve conservation tilling, crop sequencing, and seed/plant
improving. In conservation tilling (101). the increased utilization of
no-tillage and reduced tillage practice will have the following major
impacts on both water and soil quality: (1) the reduction in soil
disturbance and the greater cover of residue on the cropland will impede
soil erosion by reducing runoff, and this, in turn, will reduce the
sedimentation of the surface water. (2) Although direct runoff can be
expected to decrease, percolation and leaching will increase since a
greater part of the moisture will be retained on the cropland. (3)
With the increased utilization of conservation tilling, a greater infes-
tation of cropland by insects and diseases will occur; consequently,
increased applications of pesticides will be required and will result
in a greater potential for pesticides runoff. (4) Conservation tilling
may also result in increased nutrient runoff, however, both because of
the large amounts of organic matter in the cropland and the prospectively
greater applications of fertilizers. (5) Although total runoff will be
decreased, nitrogen concentration in that runoff may be increased. (6)
The increased percolation, will increase the potential for nitrates
entering ground water. (7) Because of the reduction in sedimentation,
movement of phosphorus to surface water will be substantially decreased.
Thus, the overall implication of conservation tillage will be the re-
duction of the potential for water and land pollution.
The trends in crop sequencing (102) carry diverse implications. The
mono-cropping and no-meadow rotation practices would tend to increase
water and land pollution. Under mono-cropping, which increases the
threat of insect and disease infestion, pesticide applications may
increase. Too, mono-cropping, depending upon the type of crop involved,
may increase or decrease erosion. (With row crops, the potential is some-
what increased; those crops affording better cover would decrease the
overall potential.) Omitting meadows from the rotation sequence would
increase erosion potential and typically require increased fertilizer
application. Both of these would contribute to water and land pollution.
Although the above crop sequencing practices would affect the environment
adversely, relay - and double-cropping may have indirect beneficial
effects. Both of these practices may impede erosion and reduce, in many
cases, fertilizer requirements on a unit of output basis, i.e., more
intensive double cropping on one location may be preferred to extensive
cropping on multiple locations. Slight increases in insecticide require-
ments would increase the potential for pesticide runoff, however.
Seed/pi ant improvements (103) environmental effects are largely
indirect.These genetic developments primarily affect crop yields
and such increases have minor impacts on any given acre of cropland.
The most significant implication stemming from increased yields would be
69
-------
a decrease in the cropland required to meet a specific level of demand,
and although the overall cropland requirements will continue to in-
crease, that increase would not be as great as it would have been
without the improved crops.
(b) Soil-water management trends. Trends in soil-water management
include practices designed to reduce runoff and soil erosion, to enhance
the moisture storage capacity of the cropland, and to decrease wind
erosion. Erosion controls (104) such as contour farming, terracing, and
the use of winter cover crops are traditional methods of stabilizing the
soil. Their use continues to increase since they are recognized to be
environmentally sound and benefit the producers. The principle feature
of these practices it that they impede runoff and retard sediment move-
ment and their environmental effect is to reduce both water and land
pollution. A secondary effect is that they increase the moisture
retained in the soil and percolated. This increased percolation
presents a greater potential for nitrates entering the ground
water.
Two trends are significant to moisture conservation (105) and storage
in the soil: fallow cropping and using agents to reduce e.vapo-
transpiration. Fallowing is common in semi-arid areas with rainfall
that is insufficient to produce a satisfactory annual crop. It not only
promotes nitrification, but it aids in controlling noxious weeds.
Additional benefits of fallowing are an increase of soil moisture and a
slight decrease in the requirements for nitrogen fertilizer and herbi-
cides. An adverse effect is the increased potential for both wind and
soil erosion, particularly when fallowing is accomplished with cultivation.
The using of agents to reduce evapotranspiration and, consequently,
increase soil moisture could significantly increase crop yields within
moisture deficient areas. The effect on the environment is similar to
that of increasing crop yields through improved crops (discussed above).
The impact is indirect, for the pressure on the increasing requirements
for cropland is slightly reduced because of the greater production levels
resulting from decreased evapo-transpiration.
Mind erosion (106) damages have been severe during such times as the
drought in the 1930's and, more recently, in the 1950's. Although
wind erosion is most severe in semi-arid and arid regions under
irrigation, it is significant on nonirrigated cropland. Strip-
cropping, barrier rows, and tree windbreaks play an important role in
offsetting the damages of wind erosion. Reducing wind erosion not only
stabilizes the soil and reduces land pollution, but it also impedes
sediment movement in active surface waters. These effects, also reduce
the potential for air and water (surface) pollution.
(c) Nutrient management trends. In nutrient management, trends with
environmental implications include new methods in applying fertilizer,
alternative nutrient sources, biological nitrogen-fixation, and certain
technological developments. New soil plant analysis techniques (107)
70
-------
for analyzing nutrient requirements of the soil and plants are being
developed and utilized. Widespread application of such analyses are
expected in the future with benefits not only to crop yield but also
to the environment. The significant effect of these analyses is a
potential reduction in unnecessary applications of fertilizers and an
associated reduction in nutrient runoff.
Methods of nutrient application (108) of commercial fertilizer are
receiving increasing utilization. These methods are generally more
efficient and cause less soil disturbance during application. Multiple
applications are designed to apply the fertilizers on the cropland during
times which are most beneficial for nutrient uptake by the plants;
this reduces the rate of application during any one period and, conse-
quently, lessens the potential for nutrient runoff. However, multiple
applications increase, to a small degree, soil disturbance with a
resultant increase in soil erosion potential.
Fall application of fertilizer is increasing significantly. This practice
has both beneficial and detrimental effects. The major benefit is that
it precludes the application of fertilizer in the spring time when the
ground is most vulnerable to erosion forces. On the other hand, the
fertilizer remains in the soil a longer period of time before plant uptake
and is subject to greater runoff, e.g., snowmelt, and leaching. Also, through
percolation, the potential for contaminating surface waters is slightly greate
although there is no evidence to show that this has become a problem.
With the increasing sizes of farms, use of floaters in crop management
has been increasing dramatically. The high flotation lines reduce com-
paction and soil disturbance and facilitate a more efficient application
of fertilizers on the cropland. This reduces both problems in sedimen-
tation and nutrient runoff. Although application of fertilizer by air-
craft is relatively minor at the present, the development of high con-
centration and foliar types of fertilizer are expected to make this
type of application more feasible. This delivery system would facilitate
fertilization of cropland at the time nutrient intake was the greatest in
the crops and would lessen the amounts of fertilizer subject to runoff.
Additionally, there would be little disturbance of the soil with a min-
imum risk of soil erosion.
Alternative nutrient sources (109) are expected to become more
important in crop production. This will result primarily from disposal
requirements for feedlot and municipal wastes. Cropland is often a
feasible type of land on which these wastes can be disposed. Disposal
is normally accomplished by spreading without incorporation; consequently
nutrients contained in these wastes are often more vulnerable to runoff
than those in commerical fertilizer. In addition problems with other
fertilizers may occur (an inherent difficulty is determining nutrient
content of the wastes and nutrient release to the soil). Another
problem may exist with heavy metals in municipal waste when applied on
cropland.
71
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Biological nitrogen-fixation (110) developments are expected to have
far reaching effects on crop production in the future. Expected
developments include ways of using nitrogen more efficiently, means
of increasing the nitrogen fixing by plant micro-organism, and methods
of improving symbiotic relationships between plants and micro-organisms.
Also, genetic developments are anticipated in introducing nitrogen-fixing
capabilities into non-legume plants requiring high applications of ferti-
lizers such as corn. With such nitrogen fixation developments consider-
able reductions in fertilizer use would occur. This would reduce
potential nitrogen runoff and leaching.
Improved fertilizers (111) developments are expected to occur in the
future which will have major effects on practices in nutrient manage-
ment. Control!ed-release fertilizers will decrease the runoff potential
of nitrogen into surface water and will decrease the eutrophication in
those waters that do receive nutrient loading from fertilizers applied
to cropland. Additionally, this development will increase the efficiency
of nutrient intake of crops which will reduce the amounts of nutrients
available for runoff and leaching. Development of nitrification and
leaching inhibitors will reduce problems associated with contamination
of ground water. These collective trends in nutrient management (other
than the increasing use of fertilizers) are expected to have an overall
beneficial effect on the environment.
(d) Pest control trends JVTrends in pest control include improved
methods of application, scouting, developments in new pesticides,
resistant crops and biological controls. Scouting (112) both surface
and by remote sensing, is expected to reduce overall pesticide use by
reducing the requirements for continued application in areas in which
there is no threat of pest infestation.
Improvements in application practices (113) are expected to have
beneficial effects, improvements in aerial application techniques will
reduce the amount of pesticides applied to non-target areas with a
consequent reduction in pesticide use and a greater efficiency of
application. These improvements will result in an increasing share of
all pesticides being applied by aircraft. Also, the increasing use of
floaters not only promotes efficiency in the application of pesticides,
but also facilitates more timely applications. The combined effects of
these improvements will be a reduction in pesticide requirements. In
addition to the reductions in potential pesticide pollution, a slight
reduction in soil erosion will be associated with the floater application.
Developments in dual application of fertilizer and pesticides will carry
both favorable and unfavorable implications. Dual application decreases
the movement of vehicles across the cropland which would lessen somewhat
- See subsection C-2: Trends and Environmental Implications, for changes
in trend groupings by the evaluation workshop.
72
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the disturbance of the soil. However, applications under this technique
are generally not optimal for both fertilizer and pesticide use. Conse-
quently, one of the two would be subject to runoff for a period of time
greater than necessary.
More resistant crop (114) developments are expected to reduce the
requirements for pesticides. The most beneficial developments are
anticipated in the area of new improved crops resistant to pests such
as insects, nematodes, birds, plus diseases. Although no dramatic
developments are expected soon, gradual improvements are envisioned
which will alleviate some of the potential pesticide problems.
New pesticides (115) are being developed which will have environmental
implications. They include formulations such as micro-encapsulated and
systemic pesticides. The benefits from these will be derived from their
greater efficiencies and the associated reduction in the total level of
pesticides required. Surfactants for herbicides will facilitate more
timely applications and the use of alternative pesticides. Significant
impacts are expected with developments of biodegradable pesticides. These
will reduce both the contamination of water (surface and ground) and of
the soil itself.
Biological control (116) developments are expected which will also
influence pest control practices. Potential developments involve the
use of juvenile hormones, pheromones, sterile males, predators, and para-
sites. Both beneficial and adverse effects may occur with these develop-
ments. Biological control, in some cases, would decrease the requirements
for pesticides on specific crops. This, of course, would reduce potential
pollution problems: however, the introduction of these biological controls
could have potential damaging effects on the environment if they affected
non-targeted plants or beneficial insects.
(e) Resource use trends. The trends discussed above were viewed in
light of impacts which were expected to occur from changes in practices
as utilized on a single unit of cropland. In many cases the practices
involved changes in the use of resources such as land, pesticides, and
fertilizer. Collectively these practices may be expected to have signi-
ficant effects on resource use and hence on the environment, although
the trends with an overriding importance are those of the increasing
levels of agriculture inputs associated with the increasing demand for
food. The inputs that pose significant environmental implications are
fertilizers, pesticides, and land. By the year 2010, the use of ferti-
lizers and pesticides is projected to increase well over a 100 percent
while land required for nonirrigated cropland is projected to increase
by fifteen percent. These increases, which constitute the basic forces
on the environment, bring into focus the fundamental problems involving
water, air, and land pollution. All of the practices and developments
previously identified must be viewed in this perspective.
73
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SECTION VII
ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVICULTURAL TRENDS:
PANEL 2 - IRRIGATED CROP PRODUCTION
The Irrigated Crop Production Panel assessed and ranked the major en-
vironmentally related trends in its' own area of expertise. Using as
a basis the preliminary report of trends (see Part C: "Background
Summary," below) the panel evaluated and ranked irrigated crop produc-
tion trends as shown in Exhibit VII-1. A brief description of the top
ten trends, and comments concerning their environmental implications,
are contained in Exhibit VII-2. Furthermore, the panel's extensiveness
of use and intensiveness of effects ratings, which were developed as a
means for establishing an overall environmental rating, are presented
in Exhibit VII-3. These exhibits are discussed further below.
Panel 2 was comprised of four members and was chaired by R. S. Rauschkalb.
It represented a broad background in areas such as economics, crop produc-
tion, water resource contraol, and irrigation engineering.
Name
Charles M. Hohn
G. L. Horner
Gene Merrill
R. S. Rauschkalb
Representing
New Mex. St. Un.
USDA-ERS
St. of Calif.
Un. of Calif.
Specialty
Location
Irrigation engineer Las Cruces, NM
Economics Davis, CA
Water Res. Contr. Sacramento, CA
Crop production Davis, CA
A. Major Trend Rankings and Practices Assessments
As discussed previously, (Section IV, "Workshop Procedures") the procedure
used by the panel in assessing trends involved an analysis of the exten-
siveness (E) and intensiveness of effect (I) of each of the subtrends.
The product of these two ratings gave a significance rating for the sub-
trend. Based on an examination of the ratings of all of the subtrends,
a composite rating was assigned to each major trend. The final step in
ranking the trends was an evaluation of all of the trends and a subsequent
adjustment of the ratings in order to reflect a proper weighting among the
trends.
Although the Contractor's preliminary report was used as a basis of the
panel's assessment, the panel was given the opportunity to modify the
74
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trend categories contained in the report. In the case of Panel 2, a
number of modifications were made and are discussed below. Included in
the trends contained in the preliminary report were a number involving
pest control. The panel did not feel that it had sufficient competence
in pesticides to adequately assess the implications of these trends.
Exhibit VII-1. Ranking of environmentally-related trends, 1976-2010:
Irrigated Crop Production
Panel
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Trend
Number
(208)
(204)
(211)
(220)
(210)
(209)
(206)
(203)
(213)
(214)
(221)
(202)
(212)
(201)
(205)
(207)
Trend
Improving water application
Runoff & erosion control
Methods of nutrient application
Developing integrated controls
Using soil-plant analysis
Directly monitoring irrigation needs
Using sprinkler irrigation
Seed/plant improvement
Developing nitrogen-fixation sources
Developing improved fertilizers
Using increased rates and amounts of crop
production
Crop sequencing
Using alternative nutrient sources
Conservation tilling
Wind erosion control
Using drip or trickle irrigation
Adjusted
Rating
22
18
15
12
9
7
6
5
5
4
3
3
3
2
2
1
75
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Exhibit VII-2. Description of major environmentally-related trends, 1976-2010: Irrigated Crc; Production
Panel
Rank
Trend Number and Title
Adjusted Rating
for 2010
Comments and Modifications
(208) Improving Water Application
(204) Runoff £ Erosion Control
(211) Methods of Nutrient Application
18
15
en
(220) Developing Integrated Pest Controls 12
(210) Use of Soil-Plant Analysis
(209) Directly Monitoring Irrigation
Needs
(206) Using Sprinkler Irrigation
(203) Seed/Plant Improving
(213) Developing Nitrogen-Fixation
Sources
(214) Developing Improved Fertilizers
This trend encompasses those practices which tend to optimize
water application to crops and includes irrigation develop-
ments and scheduling systems. These practices are expected
to have beneficial effects by improving both production
efficiency and soil quality, (i.e., reduce pollution loading of
sediment, salinity, etc)
Runoff and erosion control include measures such as contour
farming, terracing, and using winter crops in order to
stabilize the soil to impede soil movement and water runoff.
An important subtrend identified by the panel was land
grading.
New techniques and methods of applying fertilizer are being
developed and adopted which increase the efficiency of
fertilization and have potential environmental implications
by reducing run-off.
Integration of biological, chemical, and mechanical methods
not only increase the efficiency of pest control but benefit
the environment as a result of the reduction of pesticide use.
Increasing use of techniques in soil-plant analyses is
expected to benefit the environment through more efficient
nutrient management.
Systems used to monitor irrigation requirements significantly
improve the efficiency of water application and benefit the
environment.
Sprinkler irrigation is roost effective when used in connec-
tion with shallow rooted plants.
Seed/plant improvements while generally favorable to crop
yields were expected to adversely affect the environment
because of increasing soil salinity.
Expected developments include ways of using nitrogen more
effic-'°ntly, means of increasing the nitrogen fixed by plant
micro-organisms, and methods of improving the symbiotic re-
lationships between plants and micro-organisms. These
developments would result in appreicable reductions in fer-
tilizer requirements, and reduce nutrient loss in runoff.
Developments in controlled release and nitrate Inhibitors are
expected to increase the efficiency of nutrient application
and benefit the environment, by reducing nutrient loading.
-------
Exhibit VII-3. Environmental ratings of top ten trends and associated
practices: Irrigated Crop Production
Panel
Rank
Trend
Number
Trend and Subtrend
Extensiveness
Trend Rating
T57619852010
Intensiveness
Rating
2010
4
5
6
10
(208) Improving Mater Application
a. Furrow basin
b. Large sprinklers
c. Recycling & controlling tail water
d. Timing and amount with respect
to crop and soil condition
e. Irrigation scheduling
(204) Runoff & Erosion Control
IT. Contour farming
b. Terraces & grass waterways
c. Winter cover crop
d. Land grading
(211) Methods of Nutrient Application
aTFoliar application
b. Multiple applications
c. Fall application
d. Aerial & floater application
e. Improved nutrient placement
f. Irrigation application
(220) Developing Integrated Controls
(210) Using Soil-Plant Analysis
(209) Directly Monitoring Irrigation Needs
a. Measuring soil moisture content
b. demote sensing of plant or soil
water stress
c. Field soil examination
(206) Using Sprinkler Irrigation
(203) Seed/Plant Improving
a. Weather resistance
b. Salt tolerance
c. Production efficiency
(213) Developing Nitrogen-Fixation Sources
a"! Legume sources
b. Non-legume sources
. c. Non-symbiotic non-legume
(214) Developing Improved Fertilizers
a. Controlled release ferti1izers
b. High phosphate content fertilizers
c. Liquid
d. Nitrate inhibitors
0
1
1
2
1
1
0
0
1
2
1
0
0
0
3
4
2
1
0
1
5
1
3
1
2
3
2
1
3
1
1
0
0
1
2
2
1
0
0
4
5
3
2
4
1
3
4
3
1
4
2
1
3
2
2
+1
-1
+3
+3
+5
+1
+2
+2
+5
+1
+3
-1
-1
+3
-H
+2
+3
+3
+2
+2
-3
+1
+4
+4
+2
0
0
+1
77
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Consequently, the list of trends ranked by the panel excludes the pest
control trends, (specifically Trends 215 through 219) except for De-
veloping Integrated Controls (220). This trend was considered to cover
other aspects of pest control relating to crop management which were
within this panel's area of expertise. However, the panel did not want
the other trend exclusions to imply that pest control trends were not
considered important enough to be ranked among the top ten.
B. Environmental Implications of Major
Trends and Practices
Each of the major irrigated crop production trends, as determined by
Panel 2, are summarized below. Background descriptions and definitions
of these trends which served as the basis for the workshop's evaluations,
are included in Part C: "Background Summary," for reference as needed.
Improving Hater Application (208). This trend represents a modification
of the trend included in the preliminary report (see Part C) as "reducing"
water application. The panel concluded that "improving water application"
was a more appropriate classification since there are considerable areas
in which application will be increased. The trend, as viewed by the panel,
reflects a general movement towards an optimization of water application.
This trend includes practices (subtrends) which are expected to occur in
irrigation developments and improvements in scheduling. As reflected in
Exhibit VII-3, the use of furrow basins and large sprinklers will be vir-
tually eliminated by 2010 with the introduction of more modern systems.
The extensiveness of use of systems involving recycling and controlling
tail water was considered to be only limited in 1976 but was expected to
increase to an important level by 2010. The intensiveness of the effects
of these systems was considered by the panel to be moderate.
Practices specifically involving the proper timing and amount of applica-
tion were considered to be in moderate use (extensiveness) in 1976 and
were expected, by the panel, to be used widespread in 2010 as reflected
in the major rating. The intensiveness (environmental effect) was rated
as moderate for these practices. The practice expected to have the greatest
environmental impact in 2010 involved irrigation scheduling; it was rated
to have a major intensiveness of effect. In extensiveness, its use was
considered minor in 1976 but was expected to increase to moderate by 2010.
Runoff and Erosion Control (204). This trend includes those measures de-
signed to stabilize the soil such as contour farming, terracing, and land
grading. The latter was a practice identified by the panel which was not
included in the preliminary report. The effect of the stabilization brought
about by these measures enhances water quality by reducing sedimentation
and promotes the retention of the soil quality. Contour farming was con-
sidered by the panel to be of minor importance in irrigated crop production
both in extensiveness of use and intensiveness of effect. According to
panel, very little terracing or use of grass waterways was done in 1976;
78
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even'for 2010, only minor use was expected as reflected in the extensiveness
rating. The effect in the areas where they will be used was expected to be
beneficial but only of limited importance. The extensiveness in the use
of winter coyer crops was considered minor in 1976 and was not expected to
increase in importance by 2010. The intensiveness of the effect of the
practice was expected to be beneficial but again of limited importance.
Land grading was considered to be used widely in 1976 and was expected to
be of major importance (in extensiveness) by 2010. Also, the environmental
effects were expected to be of major significance.
Methods of Nutrient Application (211). A number of innovations in apply-
ing commercial fertilizers have been adopted and are being developed which
affect the efficiency of nutrient management. In many cases, these prac-
tices will have environmental implications both favorable and unfavorable.
Two practices which the panel felt would have the most beneficial effects
were multiple applications and improved nutrient placement. Both of these
practices were rated by the panel as having only limited extensiveness of
use in 1976 but were expected to have wider application in 2010, receiving
a moderate rating. The intensiveness of effect was expected to be moderate
by 2010. Foliar application and application in irrigation were expected to
have only minor impacts as shown in the intensiveness rating. Extensiveness
ratings of these practices ranged from minor to moderate. Two practices were
considered to have potentially adverse impacts, although the actual effects
were expected to be minor. Fall application was expected to pose greater
potential problems in runoff. However, the extensiveness of use was expected
to be minor; consequently, the overall problem was not considered to be signifi-
cant. Aerial and floater applications were expected to have a minor but
detrimental effect principally because of the drift problems associated with
aircraft. By 2010, application by these two type vehicles was expected to
be at a moderate level.
Developing Integrated Controls (220). The trend in the integration of
mechanical, biological, and chemical measures was considered by the panel
to have a beneficial effect on the environment because of the overall
reductions in pesticide requirements. According to the panel, this system
found only limited use in 1976 but is expected to find an increasing use in
the future as reflected in the important extensiveness rating received for
2010. The intensiveness in effect of this system was rated as of limited
importance in 2010.
Use of Soil-Plant Analysis (210). This trend is a modification of the
trend described in the preliminary report as the "improving of soil-
plant analysis". In the view of the panel, the significant aspect of
the trend was the increasing use of these techniques. Any improvement
was considered secondary. According to the panel, the use of these tech-
niques was minor in 1976; however, it will increase in the future to
moderate level in 2010. The intensiveness of effect was expected to be
moderate by 2010.
79
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Directly Monitoring Irrigation (209). A requirement for efficient water
application is the direct monitoring of irrigation needs. Systems designed
to accomplish this benefit crop yield and generally benefit the environment
by conserving water and, in many cases, reducing the salinity of the soil.
Monitoring involves practices such as measuring soil moisture content, re-
mote sensing of plant or soil stress, and examining field soil. According
to the panel, the practice having the greatest beneficial effect is that of
measuring soil moisture content. It received a moderate rating in intensive-
ness. Although its extensiveness in use was considered minor for 1976, it
is expected to increase to moderate by 2010. Remote sensing had very little
application during 1976. However, its use was expected to increase somewhat
by 2010. Its intensiveness of effect was rated as minor by the panel. Field
soil examination using augers was considered by the panel to have minor appli-
cation in 1976 and was not expected to increase significantly by 2010. The
intensiveness of effect on the environment was expected to have only limited
importance by 2010.
Using Sprinkler Irrigation (206). This type of irrigation is being used
principally for shallow rooted and high value plants. This method is
generally more efficient than furrow and promotes water conservation. Based
on this conservational aspect, the panel rated its intensiveness in 2010 as
beneficial but only of limited importance. The panel rated this practice
as having only limited application (extensiveness) in 2010.
Seed/PI ant Improving (203). Three types of improvements were considered by
the panel as having environmental implications: weather resistance, salt
tolerance, and production efficiency. Those improvements involving increased
weather resistance and production efficiency were expected by the panel to
have beneficial effects although minor as shown in the intensiveness rating.
Additionally the extensiveness of these two type improvements was expected
to be of minor or limited importance by 2010. Improvements in salt tolerance
were expected to have adverse effects on the environment with an increase in
soil salinity as a result of an overall increase in water use. The panel
rated this intensiveness of effect as moderate. In extensiveness, the panel
considered these improvements to be of limited importance in 1976 but ex-
pected then to increase to an important level by 2010.
Developing Nitrogen-Fixation Sources (213). The panel considered both legume
and non-legume sources in their assessment of expected developments. In
addition to these two, which were contained in the preliminary report, it also
considered nitrogen-fixation by non-symbiotic non-legume sources. In their
assessment, the panel concluded that fixation in legumes was minor in 1976
and was expected to be of only limited importance in 2010. Fixation by non-
legume source (including non-symbiotic) is expected to occur only through long
term research. According to the panel, these types were expected to find
only a minor level of application by 2010. In intensiveness, nitrogen-
fixation by legume sources was expected to have only a limited effect while
that of non-legumes was expected to have a major effect.
-------
Developing Improved Fertilizers (214). The panel examined a number of
potential developments involving fertilizers and concluded that there
would probably be no great environmental impact from these trends. The
only developments which were considered to have an effect were those
related to controlled fertilizers (limited in intensiveness) and nitrate
inhibitors (minor in intensiveness). The panel emphasized that the im-
portance of controlled fertilizers would not be those associated with
slow-release.
Other Trends. Other trends assessed included using Increased Rates and
Amounts of Crop Production Inputs (221), Crop Sequencing (202), Using
Alternative Nutrient Sources (212), Conservation Tilling (201), Wind Ero-
sion Control (205), and Using Drip or Trickle Irrigation (207). The panel
concluded that the impacts from these trends would be relatively minor.
C. Background Summary
The following descriptions and definitions of trends and management
practices (subtrends) related to irrigated crop production were pro-
vided to the workshop participants as background for the workshop eval-
uation. In some cases, the panel members chose to re-group selected
subtrends or add/delete subtrends as noted. As such, this summary is
quasi-independent of the workshop results as presented in Parts A and
B, above. However, it provides appropriate background base data; de-
finitions and descriptions of the trends and practices assessed in this
portion of the overall study.
1. Overview and Base Data
During 1972-74, an estimated 35 million acres of harvested cropland or
about 10 percent of the nation's total, were classified as irrigated. I/
Exhibit VII-4 shows the irrigated cropland as a percent of the total U.S.
cropland harvested in 1969. Essentially all of the irrigated cropland
was located in the seventeen Western States and Louisiana, Arkansas and
Florida. About 3 million acres or 2.3 percent of the cropland in the
thirty Eastern States was irrigated, and most was located in Louisiana,
Arkansas, and Florida. In the seventeen Western States, there was a total
of about 29 million acres of irrigated cropland or 23 percent of the total
cropland. About 40 percent of the total irrigated cropland was located in
two states: California with 6.9 million acres and Texas with 6.8 million.
Only two Western States had no significant amounts of irrigation of crop-
land—North and South Dakota, each with less than 200 thousand acres each.
Exhibit VII-5 shows the total irrigated cropland in specified crops and
-' In 1974, a total of 40.4 million acres was classified as irrigated land,
but only an estimated 35 million acres were harvested cropland.
81
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Exhibit VII-4. Irrigated cropland harvested as a percent of total cropland harvested: 1969
00
--
Alaska -- 7%
Hawaii -- 40%
-------
Exhibit VII-5. Irrigated cropland in specified crops and pasture on farms: 1969
00
CO
1,000
THOUSANDS OF ACRES IRRIGATED
2.000 3.000
4,000
ALFALFA HAY AND MIXTURES
SORGHUM FOR GRAIN I
CORN FOR GRAIN
COTTON I
CROPLAND PASTURE
HAY OTHER THAN ALFALFA
LAND IN ORCHARDS
ALL WHEAT
ALL VEGETABLES
BARLEY FOR GRAIN |
CORN FOR SILAGE
IRISH POTATOES
SOYBEANS FOR BEANS
OATS FOR GRAIN
ALFALFA SEED
PEANUTS FOR NUTS |
NURSERY AND GREENHOUSE
TOBACCO • 110
HAY CROPS CUT AND FED GREEN • 92
SORGHUMS FOR SILAGE • 91
ALL OTHER CROPS
0
1.000
2,000 3,000
THOUSANDS OF ACRES IRRIGATED
4.000
Source: Department of U.S. Commerce, 1969 Census of Agriculture.
-------
pastures in 1969. Hay (alfalfa and other types) accounted for about 7.5
million acres. Sorghum, corn, and cotton each accounted for over 3 mil-
lion acres. Wheat was irrigated on less than 2 million acres, and soy-
beans on about 0.7 million acres.
The total irrigated cropland harvested has continued to rise and is pro-
jected to increase to 37 million acres by 1985 and to remain at that
level through the year 2010. The greatest increase is expected to occur
in Texas, and other significant increases are projected for California,
Florida, Nebraska, and Kansas.
Crop production on irrigated cropland contributes, in varying degrees,
to the pollution of water, air, and land. It can also cause other en-
vironmental damages to the ecology, to aesthetics, and to human health.
The potential irrigated cropland pollutants include sediment, pesticides,
fertilizer, animal and municipal wastes, crop residue, and irrigation re-
turn flow salinity. These are considered major pollutants, and they are
variously transported to water and air. They contribute to water pollu-
tion through direct runoff, sediment movement, percolation, and to a
small extent by wind erosion. They contribute to air pollution by wind
erosion and volatilization.
Significant pollution problems are posed both to surface water (streams
and rivers) and ground water by pollutants from irrigated cropland. The
major surface water pollutant (by volume) is sediment resulting from soil
erosion. While soil erosion per se is not a major concern in irrigated
cropland, the sediment yielded appreciably increases sediment loading
above the background loading and also carries other pollutants such as
pesticides and fertilizers.
Fertilizer and pesticide pollution is receiving growing concern, for
these pollutants affect not only surface but also ground water. Ferti-
lizer pollution problems can be expected to occur in those geographical
areas having considerable cropland acreage receiving high rates of appli-
cation. Exhibit VII-6 shows these areas for sorghum, vegetables, cotton,
wheat and orchard cropland. Irrigated wheat cropland receiving some of
the highest rates is located principally in the western parts of Kansas,
Oklahoma, and Texas and in the eastern part of Washington. The major
pollution problems from the fertilization of irrigated cotton and sor-
ghums occur primarily in Texas. The Imperial Valley of California and
the southern part of Texas face major problems stemming from irrigation
of orchard and vegetable cropland.
Commercial fertilizers contain the plant nutrients nitrogen (N), phos-
phorus (p), and potassium (K). Since there is no evidence that potas-
sium causes any significant problems in water pollution, the only two
nutrients having environmental implications are nitrogen and phosphorus.
Nitrate nitrogen, soluble in water, pollutes surface waters through di-
rect runoff and ground water through percolation. Phosphorus, rela-
tively insoluble, is of concern primarily for surface water pollution.
Attached to sediment, it enters the water via sediment movement.
84
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Exhibit VII-6. Irrigated cropland receiving high rates of fertilization.
'S-
in
Uheat
Cotton
Veqetables \
Sorghum Orchards
^^ —
Source: Control of Water Pollution from Cropland. Volume I. USDA, EPA. 1975
-------
Although commercial fertilizers provide the major source of plant nutrients,
animal wastes (manure) provide a significant source in feedlot and dairy
farm areas. Manure can pose significant problems in local areas when high rates
per acre are applied. Exhibit VII-7 shows the major areas of feedlot and
dairy farm concentrations.
Manure from beef feedlots can be expected to pose major pollution problems
on irrigated cropland in the Texas Panhandle and in the eastern part of
Colorado. Milk cow and poultry wastes present pollution problems to irrigated
cropland primarily in the Imperial Valley.
Pollutants from pesticides, while minor in terms of total volume, have been
receiving increasing public interest because of the toxicity and persistence
of some. Pollution problems can be expected in those areas in which crop-
land receives high rates of application, but there is little documentation
to indicate any significant national problems. Exhibit VII-8 shows the crop-
land areas treated with herbicides and insecticides in 1969. These pesticides
were used chiefly on irrigated cropland in the Texas Panhandle, in the Imperial
Valley of California, and in Washington. Although there has been no compre-
hensive documentation of the pesticide runoff on irrigated cropland, a number
of research projects investigating runoff on limited scales have been con-
ducted. These projects lead to the general conclusion that runoff is less
than 5 percent of the amount applied.
Irrigation return flow salinity is a significant pollutant to surface water,
ground water, and soil composition. The major components of salinity .[salinity s
the presence of dissolved solids in the water] include water-soluble compounds
of the cations calcium, magnesium, sodium, and potassium and of the anions
carbonate, bicarbonate, sulfate, and chloride. Minor amounts of iron,
aluminum, manganese, and other cations are also present. Salinity, or
salt pickup, occurs during normal irrigation practices as a portion of the
irrigation water is carried to the subsoil or ground water. This percolat-
ing water, carrying with it salts accumulated in the root zone, can move
up or down in the soil profile. Some is eventually collected by drains and
returned to the main stream, and the salt concentration of the irrigation
return flow may be two to five times that of the initial irrigation water.
Another fraction accumulates on or near the surface.
Salinity problems are associated principally with cropland irrigated with
surface water. They are particularly acute in California, Arizona, and New
Mexico where over 50 percent of the water supplied to irrigated cropland
stems from surface sources and in Montana, Wyoming, Washington, Utah, and
North Dakota where about 90 percent of the irrigation water is from such
sources.
86
-------
Exhibit VII-7. Concentrations of feedlots which include dairy farms, beef, hogs, and chickens.
3eef
Dairy Farms
Hogs
Source: Control of Water Pollution from Cropland. Volume I.
Chickens
USDA, EPA. 1975
-------
Exhibit VII-8. Croplands treated with pesticides
and herbicides: 1969
Acreage of non-hay crops treated with insecticides
Acreage of crops treated with herbicides
Source: Control of Water Pollution from Cropland. Volume I
USDA, EPA. 1975.
88
-------
2. Trends and Environmental Implications
Crop production on irrigated cropland encompasses a wide variety of
management practices which differ considerably among crops and among
geographical regions. Although the entire production system must be
viewed to assess the total impact of this cropland on the environment,
each of the practices can be examined to determine its specific environ-
mental implications.
Trends. The general relationships of these management practices within
the production system are illustrated in Exhibit VII-9. Included in
the system are the management practices (resource management), resource
inputs, technological developments, and the production outputs (including
residuals generated). This system provides the framework in which the
trends in crop production on irrigated cropland have been identified.
Those trends discussed and analyzed are listed in Exhibit VII-10 and
subsequently described in Exhibit VII-11. The specific trends have
been grouped under the following major practices: (1) crop management,
(2) soil-water management, (3) nutrient management, and (4) pest control.
The trends, expressed in brief terms, implicitly reflect the adoption or
the increasing utilization of the specific management practice.
Environmental Implications. In the analysis of the trends, a matrix
(Exhibit VII-12) was developed so that the potential interactions be-
tween the specific practices and the generation of pollutants could be
examined. These interactions represent changes that would have occurred
in the amount of pollutants produced on a representative unit of produc-
tion (acre of irrigated cropland) had it been cropped under conventional
practice and conditions prevalent in 1976. The interactions were denoted
by pluses (+) and minuses (-) [+ represents a decreasing effect or bene-
ficial environmental impact; - denotes an adverse environmental impact].
The matrix not only illustrates the interactions between specific practices
and pollutants generated, but also represents, in certain cases, logical
interactions among practices. For example, the primary impact of no-till
planting is a decrease in soil sediment. However, no-till requires an
attendant increase in the use of pesticides. Consequently, this increase
was reflected in the matrix as an interaction between the practice of no-
till and the generation pesticide pollutants. Based on a review of the
interactions displayed in the matrix, general conclusions were drawn
concerning trends and environmental implications.
(a) Crop management trends. The principal trends projected in crop
management involve conservation tilling, crop sequencing, and seed/plant
improving. In conservation tilling (201), the increased utilization of
no-tillage and reduced tillage practice will have the following major
impacts on both water and soil quality: (1) the reduction in soil
disturbance and the greater cover of residue on the cropland will impede
soil erosion by reducing runoff, and this, in turn, will reduce the
sedimentation of the surface water. (2) Although direct runoff can be
expected to decrease, percolation and leaching will increase since a
89
-------
greater part of the moisture will be retained on the cropland. (3)
With the increased utilization of conservation tilling, a greater infes-
tation of cropland by insects and diseases will occur; consequently,
increased applications of pesticides will be required and will result
in a greater potential for pesticides runoff. (4) Conservation tilling
may also result in increased nutrient runoff, however, both because of
the large amounts of organic matter in the cropland and the prospectively
greater applications of fertilizers. (5) Although total runoff will be
decreased, nitrogen concentration in that runoff may be increased. (6)
The increased percolation, will increase the potential for nitrates
entering ground water. (7) Because of the reduction in sedimentation,
movement of phosphorus to surface water will be substantially decreased.
Thus, the overall implication of conservation tillage will be the re-
duction of the potential for water and land pollution.
Exhibit VII-9. Crop production system: Irrigated Cropland
IMPROVED
MECHAN-
IZATION
!AJI-
TMI
VEL
CROP
IMPROVEMENT
(Breeding)
1
,
SEEDS
• *
FERTILIZER
DEVELOPMENT
PUNTING
FERTILIZER
( An 1 mj 1
wastes)
f
r 1
PESTICIDE BIOLOGICAL
DEVELOPMENT CEVELCPKEM
KICRO-
P"TICIDES CUAMBS
•
NUTRIENT
"AN5KKENT
{
,
j
T
.1
PEST
IRRIMTlCt
CONTROL
MA
IK CCXTRO:
TECHNOLOGY
OUTPUT
OUTPUT
90
-------
Exhibit VII-10. Environmentally-related agricultural trends
Irrigated Cropland
CROP MANAGEMENT TRENDS
201. CONSERVATION TILLING
a. No-till age
b. Reduced tillage: chisel,
piowing,. undercutti ng, chemi cal
202. CROP SEQUENCING
a. Mono-crop sequencing
b. No-meadow crop sequencing
c. Relay cropping
d. Double cropping
203. SEED/PLANT IMPROVING
(Genetic development)
a. Weather resistance
b. Salt tolerance
c. Production efficiency
SOIL WATER MANAGEMENT TRENDS
204. RUN-OFF AND EROSION CONTROLLING
a. Contour farming: contour planting,
contour-strip cropping
b. Using terraces and
c. Using winter cover crops
d. Optimizing time of operations;
tillage, planting
e. Using narrow rows
f. Using chemical erosion-control agents
205. WIND-EROSION CONTROLLING
a. Using strip-cropping (with furrow and solid
set sprinkler irrigation)
b. Using barrier rows (crops)
c. Using free windbreaks
206. USING SPRINKLER IRRIGATION
207. USING DRIP OR TRICKLE IRRIGATION
208. REDUCING WATER APPLICATION
a. Using furrow basin
b. Using large sprinklers
c. Applying less frequently
d. Recycling and controlling tailwater
91
-------
Exhibit VII-10 (continued)
209. DIRECTLY MONITORING IRRIGATION NEEDS
a. Measuring soil moisture content
b. Remote sensing at plant or soil water stress
NUTRIENT MANAGEMENT TRENDS
210. IMPROVING SOIL-PLANT ANALYSIS
(Crop logging)
211. METHODS OF NUTRIENT APPLYING
a. Using foliar fertilization
b. Using fertigation
c. Using multiple applications
d. Using aerial and floater vehicle application
e. Using fall fertilization
f. Using liquid fertilizers
212. USING ALTERNATIVE NUTRIENT SOURCES
a. Using animal wastes
b. Using municipal treatment plant wastes
c. Using green manure crops
213. DEVELOPING BIOLOGICAL NITROGEN-FIXATION SOURCES
a. Developing legume sources
b. Developing non-legume sources
214. DEVELOPING IMPROVED FERTILIZERS
a. Developing controlled-release fertilizers
b. Developing high nitrogen content fertilizers
c. Developing high phosphorus content fertilizers
PEST CONTROL TRENDS V
215. USING SCOUTING
a. Using surface scouting
b. Using remote sensing scouting
216. IMPROVING PESTICIDE APPLICATION METHODS AND TIMING
a. Improving aerial application
b. Improving floater vehicle application
c. Developing fertilizer and pesticide dual application
d. Improving pesticide placement
217. DEVELOPING RESISTANT CROPS
a. Developing disease resistant crops
b. Developing insect and nematode resistant crops
c. Developing bird resistant crops
92
-------
218. DEVELOPING NEW PESTICIDES
a. Developing micro-encapsulated pesticides
b. Developing systemic pesticides
c. Developing surfactants for herbicides
d. Developing bio-degradable pesticides
e. Developing alternative formulations
219. DEVELOPING BIOLOGICAL CONTROLS
a. Developing juvenile hormones
Developing pheromones
Developing sterile mal
Developing sterile males
Developing predators and parasii
220. DEVELOPING INTEGRATED CONTROLS
(i.e., chemical-biological-mechanical)
RESOURCE USE TRENDS
221. USING INCREASED RATES AND AMOUNTS OF CROP PRODUCTION INPUTS
a. Using commercial fertilizers
b. Using other nutrient sources: livestock wastes,
municipal sludges
c. Using chemical pesticides: herbicides, insecticides,
fungicides, rodenticides, etc.
d. Using energy: petroleum products, electricity, sunlight
e. Using new cropland (including set-aside lands)
*/
See Subsection C-2: Trends and Environmental Implications, for
changes in trend groupings by the evaluation workshop.
93
-------
Exhibit VII-11. Description of environmentally-related trends and
developments: Irrigated Cropland Production
CROP MANAGEMENT TRENDS
201. CONSERVATION TILLING - general reduction in cropland soil
disturbance
a. No till plant: seeding without pre-planting tillage
b. Reduced tillage: weed control and soil breaking
with limited soil inversion
202. CROP SEQUENCING - cropping patterns
a. Mono-cropping: successive planting of one crop on
the same plot of land
b. No-meadow: eliminates pastures or meadows from
rotation sequence
c. Relay cropping: planting the second crop before the
first crop is harvested
d. Double cropping: planting the second crop after the
first crop is harvested in the same growing season
203. SEED/PLANT IMPROVING
a. Weather resistance: plants genetically developed to
withstand winds, drought, etc.
b. Salt tolerance: developing plants capability to pro-
duce in a saline environment
c. Production efficiency: genetic development of plants
which utilize nutrients and sunlight more efficiently
and have desired growth characteristics of root de-
velopment, growth and maturity.
SOIL WATER MANAGEMENT TRENDS
204. Runoff and Erosion Control
a. Contour farming: farming operations are performed
according to the land evaluations
b. Terracing: soil embankments which slow the downhill
flow of surface waters
c. Cover crops: stubble mulching and grassed waterways
to slow runoff flow.
d. Optimizing time of operation: performing farm operations
to minimize the time period that the soil is bare
e. Narrow rows: reducing the distance between adjoining
rows of seeded crops
f. Chemical erosion-control: Chemical agents applied to
reduce soil erosion
94
-------
Exhibit VII-11 (continued)
205. WIND-EROSION CONTROLLING
a. Strip cropping: dividing the field in alternate
narrow bands of crop and fallow land
b. Barrier rows: use of taller crops to act as wind breaks
c. Wind breaks: planting trees and shrubs to reduce the
effect of the wind and soil loss
206. SPRINKLER IRRIGATION - application of water to crops dispersing
droplets through the air
207. USING DRIP OR TRICKLE IRRIGATION - application of water to crops
by dispersing through subsurface delivery systems
208. REDUCING WATER APPLICATION
a. Furrow basins: small earth dams used to impound water
in furrows
b. Sprinklers: dispersing irrigation water droplets
through the air
c. Limited application: reducing irrigation frequency to
eliminate over-irrigation
d. Recycling and controlling tailwater: using irrigation
water runoff for application to other crops and improving
irrigation water management.
209. DIRECTLY MONITORING IRRIGATION NEEDS
a. Measure soil moisture content: direct field probes
b. Remote sensing of plant and water stress: by using
satellite information
NUTRIENT MANAGEMENT TRENDS
210. IMPROVING SOIL-PLANT ANALYSIS (crop logging) - monitoring nutrient
uptake, soil nutrients available, and plant condition to pro-
vide information to adjust fertilizer rates, timing, and
cultural practices
211. METHODS OF NUTRIENT APPLYING
a. Foliar fertilization: applying fertilizer as a spray
so that nutrients are taken up through the leaves of the
plant
b. Fertigation: fertilizer application through irrigation
systems
c. Multiple application: fertilizer is applied more than
one time to realize optimum growth and crop production
d. Aerial and floater application: fertilizer is applied
via airplane, helicopter, or by ground machines equipped
to traverse wet or dry ground with limited soil com-
pactions
95
-------
Exhibit VII-11 (continued)
e. Fall fertilization: application of fertilizer during the
fall season prior to the crops primary growing season
d. Liquid fertilizer: application of nutrients as a liquid
to enhance crop production.
212. USING ALTERNATIVE NUTRIENT SOURCES
a. Animal wastes: solid and liquid wastes from live-
stock feedlots contain nutrients and organic matter.
b. Municipal treatment plant wastes: use of municipal
wastes as a source of nutrients
c. Green manure crops: crops grown for the intended
purpose of incorporating immature plants into the
soil structure
213. DEVELOPING BIOLOGICAL NITROGEN-FIXATION SOURCES
a. Legumes: plants capable of fixing atmospheric nitrogen
and accumulating it in root nodules
b. Non-legume: soil microbacterial populations that are
able to fix nitrogen from the air.
214. DEVELOPING IMPROVED FERTILIZERS
a. Controlled-release: chemical inhibitors to delay nitri-
fication, leaching etc. are added to fertilizers
b. High nitrogen content: use ammonia to supply a high
concentration of nitrogen
c. High phosphorus content: use of polyphosphates to
increase phosphorus content about 50 percent more than
ordinary fertilizers
PEST CONTROL TRENDS V
215. USING SCOUTING
a. Surface: determine types of pests and potential crop
damage by visual inspection
b. Remote sensing: insect populations and locations are
determined by satellite information
216. IMPROVING PESTICIDE APPLICATION METHODS AND TIMING
a. Aerial application: new methods to decrease pesticide
drift during application by increasing and homogeneous
partical size
b. Floater vehicle: can be used on wet soil for timely
application
c. Dual application: herbicides, pesticides, and liquid
fertilizer simultaneous application through irrigation
water
d. Pesticide placement: using the most effective and
efficient manner for applying pesticides
96
-------
Exhibit VII-11 (continued)
217. DEVELOPING RESISTANT CROPS
a. Disease resistant: genetically developing plant species
capable of resisting specific diseases
b. Insect and nematode resistant: genetically developing
plant species capable of resisting selected insects and
nematodes
c. Bird resistant: genetically developing plant species
that are less accessible to feeding bird populations
218. DEVELOPING NEW PESTICIDES
a. Micro-encapsulated pesticides: pesticides in micro-
capsule form that slowly release the pesticide over a
longer time period
b. Systemic pesticides: pesticide compounds that are
absorbed by the plant which make it toxic to pests
c. Surfactants: chemical materials which enhance the
adsorption and absorbtion properties of herbicides
d. Bio-degradable pesticides: chemicals which are affective
against pests and are decomposable by the environment
with limited persistence.
e. Alternative formulations: different methods combining
chemicals which are effective against pests.
219. DEVELOPING BIOLOGICAL CONTROLS
a. Juvenile hormones: Hormonal compounds capable of pre-
venting normal development and maturation of insects
b. Pheromones: chemical compounds containing organo-
phosphorus insecticide used to selectively attract
insects.
c. Sterile males: release sexual sterile insects to
decrease or control insect population
d. Predators and parasites: use of natural enemies,
fungi, virsuses, bacteria, to control insect populations
220. DEVELOPING INTEGRATED CONTROLS - integrating chemical, bio-
logical, and mechanical treatment methods to achieve desired
control over cropland production
RESOURCE USE TRENDS
221. USING INCREASED RATES AND AMOUNTS OF CROP PRODUCTION
INPUTS - increasing demands for cropland production will
affect the quantity of fertilizer, animal and municipal wastes,
chemicals, energy and land used for food production
*/
— See subsection C-2: Trends and Environmental Implications, for
changes in trend groupings by the evaluation workshop.
97
-------
Exhibit VII-12. Environmentally-related trends: Irrigated Cropland
vo
00
Potential Contribution to Pol :utior--K3icr
Surface Water Ground 1,'itar
CROP
201.
202.
203.
TRENDS Sed1- Nitro-
iMnt sen
MANAGEMENT TRENDS
CONSERVATION TILLING 4 +
a. N'o-tillace + +
b. Reduced tillage: chisel plowing.
undercutting, chemical 4 +
CROP SEQUENCING
a. Mono-crop sequencing
b. No-meadow crop sequencing
c. Relay cropping + 4
d. Couble cropping * +
SEEO/PL/OT IMPROVING (Genetic development) + 0
a. Weather resistance + 0
b. Salt tolerance 0 0
c. Production efficiency + +
Inorganic Bioae-
Ptos- Pesti- salt and gra ble
phorts cides minerals o/'sa.iics Nitrates
+ - 0
4 - o - -
4 - o - -
000
000
0 - +
4 4 0 - -
4 + 0
+ C 0 - 0
+ 00-0
00000
+ 0 0
Inorganic
Pesti- salt and
cifles minerals
0
0
0
0
0
0
0
0
0 0
0 0
0 0
0 0
Pollutants
Air
Gases
0
0
0
0
0
0
0
0
0
0
0
0
Par-
ticu- Soil Sa-
lates erosion linitv
+ + 0
+ + 0
+ + 0
0
0
0
+ + 0
+ + 0
+ + 0
+ + 0
00 0
+ + 0
Ltni
Heavy
netal s
o
o
0
0
0
o
o
0
o
o
o
0
Pesti-
cide
residues
-
.
_
-
o
o
o
0
£iode-
orgsnUs
-
0
o
0
o
SOIL WATER MANAGEMENT TRENDS
204.
205.
RUN-OFF & EROSION CONTROLLING 4 +
a. Contour farming: contour planting,
contour-strip cropping 4 +
b. Using terraces & grass waterways + +
c. Using winter cover crops 4 +
d. Optimizing time of operation:
tillage, planting + +
e. Using narrow rows 4 +
f. Using chemical erosion-control agents + +
MOISTURE CONSERVING (STORAGE) - 0
a. Fallow cropping: moisture storage,
salt-s;eps - 0
b. Using evapo-transpiration
reducing agents 4 ft
+ + 0 +
+ + 0 + -
+ + 0 +
+ + 0 +
+ +00 +
+ + 0 - +
+ +00-
+ - +
- + +
+ 000-
_
_ _
_ _
fc _
+ +
+ 0
+
+ 0
0
o
o
0
0
0
+
+
0
+ + 0
+ + 0
+ + 0
+ + 0
+ + 0
+ + 0
+ + 0
+ + 4
o
o
o
0
o
o
0
o
o
0
4
•f.
n
V
0
o
5
0
-------
Exhibit VII-12 (continued)
Potential Contribution to
Surface Water
206.
207.
208.
209.
211.
212.
TRENDS Sedi-
wnt
SPRINKLER IRRIGATION +
USING DRIP OR TRICKLE IRRIGATION +
REDUCING WATER APPLICATION +
a. Furrow basins +
b. Sprinkler +
c. Limited applicaton +
d. Recycling and controlling '. lil water +
DIRECTLY MONITORING IRRIGATION NEEDS +
a. Measure soil moisture content +
b. Remote sensing +
METHODS OF NUTRIENT APPLYING +
a. Foliar fertilization +
b. Fertigation +
c. Multiple application
d. Aerial and floater application +
e. Fall fertilization +
d. Liquid fertilizer +
USING ALTERNATIVE NUTRIENT SOURCES +
a. Using animal wastes +
b. Using municipal tr eatnent plant wastes +
c. Using green manure crops
Inorganic
(iitro- PSos- Pestl- salt sr4
Cen phorLS cid^s minerals
; : ;
+ + +
+ + 0
+ + o
+ + 0
0
+ + 0
+ + 0
+ + 0
0
0
0
+ + 0
I
*
0
0
0
0
0
0
0
0
0
0
0
Bioce-
gratiable
orqanics
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
_
_
-
-
PoHutior.--Haior Pollutants
Ground Kater
• itrates
*
+
0
+
0
_
+
_
0
.
_
-
-
cides
+
+
0
0
0
0
0
0
0
0
0
0
0
Inorganic
salt and
minerals
:
•*•
0
0
0
0
0
0
0
0
0
0
0
Air
Par-
ti cu- Soil
Gases lates erosion
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 + +
0 - -
0 + +
0 - +
0 + +
+
- +
+
•f-
Si-
linity
-
-
0
0
0
0
0
0
0
0
0
0
0
Uni
H?avy
ratals
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pesti-
cide
residues
-
-
0
0
0
0
0
0
0
0
0
0
0
orcirncs
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
Exhibit VII-12 (continued)
o
o
Potential Contribution to
Surface Water
213.
214.
TRENDS
DEVELOPING BIOLOGICAL NITROGEN-FIXATION
SOURCES
a. Developing legume sources
b. Developing non-legume sources
DEVELOPING IMPROVED FERTILIZERS
a. Developing control led-release
fertilizers
b. Developing high nitrogen content
fertilizers
c. Developing high phosphate content
fertilizers
Sedi-
ment
4
4
4
0
0
0
0
Nitro-
gen _
4
4
+
+
4
-
0
Pftos-
phg.ru j_
0
0
0
4
4
-
0
Pesti-
cides
0
0
0
0
0
0
0
Inorganic
salt and
minerals
0
0
0
0
0
0
0
3iode-
gntstrte
ornaMcs
-
-
0
0
0
0
Ground Water
nitrates
4
4
4
4
4
-
0
Pesti-
cides
0
0
0
0
0
0
0
Inorganic
salt and
minerals
0
0
0
0
0
0
0
Mr
Pir-
ticu- Soil
Gases Utes erosion
0
0
0
0
0
0
0
+
4
0
0
0
0
4
4
0
0
0
0
Sa-
.11 nit* .
0
0
0
0
0
0
0
Land
Pesti-
Heavy clde
metals residues
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bloie-
gradaol e
crqanfcs
-
-
0
0
0
0
PEST CONTROL TRENDS
215.
216.
217.
USING SCOUTING
a. Using surface scouting
b. Using remote sensing scouting
IMPROVING PESTICIDE APPLICATION
METHODS AND TIMING
a. Improving aerfaT application
b. Improving floater vehicle application
c. Developing fertilizer and pesticide
dual application
d. Improving pesticide placement
DEVELOPING RESISTANT CROPS
a. Developing disease resistant crops
b. Developing insect and nematode
resistant crops
c. Developing bird resistant crops
0
0
0
4
0
4
4
0
4
4
4
+
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
4
4
4
4
4
0
4
4
4
4
4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
4
+
4
0
4
0
+
+
4
4
+
0
0
c
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
0
4
0
0
4
4
4
4
0
0
0
4
0
4
0
0
4
4
4
4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
4
4
4
4
4
0
4
4
4
4
4
0
0
0
0
0
0
0
0
0
0
0
0
-------
Exhibit VII-12 (continued)
Surface lister
TR£NDS s*,. Nltro-
218.
219.
220.
DEVELOPING NEW PESTICIDES 0
a- Developing micro-encapsulated
pesticides 0
b. Developing systematic pesticides 0
c. Developing surfactants for herbicides 0
d. Developing bio-degradable pesticides 0
e. Developing alternative formulations 0
DEVELOPING BIOLOGICAL CONTROLS +
a. Developing juvenile hornonew +
b. Developing pherorones +
c. Developing sterile males +
d. Developing predators and parasites +
DEVELOPING INTEGRATED CONTROLS 0
(i.e., chemical-biological-mechanical)
0
0
0
0
0
0
0
0
0
0
0
0
Inorganic
Pftos- Pesti- salt ir.d
phorus ddes minerals
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +•
0 +
0
0
0
0
0
0
0
0
0
0
0
0
Pctenti a
Ccntri fcufiori to Po lutn:ri-
Ground Uater
Biodi-
gradibl e ?^sti-
orcenlcs Nitrates cides
0
0
0
0
0
0
0
0
0
0
0
0
0 +
0 +
0 +
0 -r
0 +
0 +
0 +
0 *
0 -H
0 +
0 +
0 +
"Inorganic
Silt cr.d
nlneralc
0
0
0
0
0
0
0
0
0
0
0
0
Air '-=ni
fzr-
ticu- Soil
Esses lites erosion
0
0
0
0
0
0
0
0
0
0
0
0
0 0
0 0
0 0
0 0
0 0
0 0
+ +
+ ^
+ +
+ +
+ *
0 0
Si-
Unlty
0
0
0
0
0
0
o
o
0
o
0
o
Heavy cice
Bttils rescues
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
0 +
" S'.Cie-
qrsiible
crcanics
o
o
o
o
o
0
o
o
o
o
D
o
RESOURCE USE' TRENDS
221.
USING INCREASED RATES AND AMOUNTS OF
CROP PRODUCTION INPUTS
a. Using conwercial fertilizers
b. Using other nutrient sources:
livestock wastes, municipal sludges
c. Using chemical pesticides: herbicides,
insecticides, fungicides, rodenticides -
d. Using energy: petroleum products,
electricity, sunlight 0
e. Using new cropland (including set-
aside lands)
_
_
-
0
0
-
_ _
0
0
0
0 0
-
_
0
0
0
0
-
..
_
.
0
0
-
- _
0
0
0
0 0
-
_
0
0
0
0
.
_
_
_
0
0
_
_
_
_ _
_
0 0
.
Q
0
o
o
_
0 0
0 0
0
0 0
_
_
o
o
_
-------
The trends in crop sequencing (202) carry diverse implications. The
mono-cropping and no-meadow rotation practices would tend to increase
water and land pollution. Under mono-cropping, which increases the
threat of insect and disease infestion, pesticide applications may
increase. Too, mono-cropping, depending upon the type of crop involved,
may increase or decrease erosion. (With row crops, the potential is some-
what increased; those crops affording better cover would decrease the
overall potential.) Omitting meadows from the rotation sequence would
increase erosion potential and typically require increased fertilizer
application. Both of these would contribute to water and land pollution.
Although the above crop sequencing practices would affect the environment
adversely, relay - and double-cropping may have indirect beneficial
effects. Both of these practices may impede erosion and reduce, in many
cases, fertilizer requirements on a unit of output basis, i.e., more
intensive double cropping on one location may be preferred to extensive
cropping on multiple locations. Slight increases in insecticide require-
ments would increase the potential for pesticide runoff, however.
The impacts on the environment associated with those ^eed/plant
improvements (203) included as crop management trends would largely
be indirect. These genetic developments primarily affect crop yields
and such increases have minor impacts on any given acre of cropland.
The most significant implication stemming from increased yields would be
a decrease in the cropland required to meet a specific level of demand,
and although the overall cropland requirements will continue to increase,
that increase would not be as great as it would have been without the
improved crops.
(b) Soil-water management trends. Trends in soil-water management
include practices designed to reduce runoff and soil erosion, and to
decrease wind erosion. Major trends in irrigation involve the increas-
ing use of sprinkler and to a lesser degree dry or trickle irrigation.
Erosion controls (204) such as contour farming, terracing, and the use
of winter cover crops are traditional methods of stabilizing the soil.
Their use continues to increase since they are recognized to be not only
environmentally sound but also economically profitable. The principle
feature of these practices is that they impede runoff and retard sediment
movement and their environmental effect is to reduce both water and land
pollution. A secondary effect is that they increase the moisture re-
tained in the soil and percolated. This increased percolation presents
a greater potential for nitrates entering the ground water.
The damages done through wind erosion (205) have been severe during such
times as the drought in the 1930's and, more recently, in the 1950's.
Although wind erosion is most severe in semi-arid and arid regions
under irrigation, it is significant on nonirrigated cropland. Strip-
cropping, barrier rows, and tree windbreaks play an important role in
offsetting the damages of wind erosion. Reducing wind erosion not only
stabilizes the soil and reduces land pollution, but it also impedes
sediment movement in active surface waters. These effects, also reduce
the potential for air and water (surface) pollution.
102
-------
Sprinkler irrigation (206) has been increasing significantly since World
War II with the development of more efficient sprinkler, lightweight
aluminum pipe, more efficient pumps, and low cost electrical power.
Sprinklers are being used on all types of soil and for many crops.
Their use is particularly effective on land having steep slopes and
easily erodable soils and an undulating land too costly to level for
surface irrigation.
The uniform distribution of water in sprinkler irrigation reduces the
potential for soil erosion and facilities leaching of salts from the
root zone.
Drip or trickle irrigation (207) is being used for crops grown under a
wide range of conditions, but is particularly beneficial in temperate
areas where irrigation is utilized to supplement moisture from rainfall
during the growing season. The system finds wide application for irrigat-
ing newly planted orchards and vineyards. Drip irrigation is often more
effective than other systems when used to irrigate vegetable crops
(grown on raised beds) with water having a relatively high salt content
since the salts are moved with the water away from the plant roots. In
this type of system, a potential danger from salt accumulation in the
soil exists since salts normally accumulate on the periphery of that
portion of the wet soil, when moisture is extracted from the soil, a
reversal in the flux of water from the periphery back into the root
zone can occur. With inadequate irrigation, crops can be injured by
this reverse movement of salts in saline soil conditions.
Reducing water application (208) in irrigation which is accomplished
principally for economic reasons has both beneficial and adverse effects
on the environment. The primary benefit involves the conservation of
water resources; adding excessive moisture during irrigation not only
waste water, which may be in scarce supply, but also may damage the
crop. The use of farrow basins and large sprinklers, when properly used,
may leach salts from the root zones and prevent salinity in the soil.
On the other hand, recycling and controlling tail-water may increase
problems in salinity.
Directly monitoring irrigation needs (209) is a prerequisite for the
proper management of water practices discussed above concerning reduced
irrigation. It both conserves water and promotes better crop yield.
(c) Nutrient management trends. In nutrient management, trends with
environmental implications include new methods in applying fertilizer,
alternative nutrient sources, biological nitrogen-fixation, and certain
technological developments. New soil plant analysis techniques (210)
for analyzing nutrient requirements of the soil and plants are being
developed and utilized. Widespread application of such analyses are
expected in the future with benefits not only to crop yield but also
to the environment. The significant effect of these analyses is a
potential reduction in unnecessary applications of fertilizers and an
associated reduction in nutrient runoff.
103
-------
A number of innovations involving methods of application (211) of
commercial fertilizer are receiving increasing utilization. These
methods are generally more efficient and cause less soil disturbance
during application. Multiple applications are designed to apply the
fertilizers on the cropland during times which are most beneficial for
nutrient uptake by the plants; this reduces the rate of application
during any one period and,consequently, lessens the potential for nutrient
runoff. However, multiple applications increase, to a small degree,
soil disturbance with a resultant increase in soil erosion potential.
Fall application of fertilizer is increasing significantly. This practice
has both beneficial and detrimental effects. The major benefit is that
it precludes the application of fertilizer in the spring time when the
ground is most vulnerable to erosion forces. On the other hand, the
fertilizer remains in the soil a longer period of time before plant uptake
and is subject to greater leaching. Also, through percolation, the
potential for contaminating surface waters is slightly greater although
there is no evidence to show that this has become a problem.
With the increasing sizes of farms, use of floaters in crop management
has been increasing dramatically. The high flotation lines reduce com-
paction and soil disturbance and facilitate a more efficient application
of fertilizers on the cropland. This reduces both problems in sedimen-
tation and nutrient runoff. Although application of fertilizer by air-
craft is relatively minor at the present, the development of high con-
centration and foliar types of fertilizer are expected to make this
type of application more feasible. This delivery system would facilitate
fertilization of cropland at the time nutrient intake was the greatest in
the crops which would lessen the amounts of fertilizer subject to funoff.
Additionally, there would be little disturbance of the soil with a min-
imum risk of soil erosion.
The use of alternative nutrient source (212) is expected to become more
important in crop production. This will result primarily from disposal
requirements for feedlot and municipal wastes. Cropland is often a
feasible type of land on which these wastes can be disposed. Disposal
is normally accomplished by spreading without incorporation; consequently
nutrients contained in these wastes are often more vulnerable to runoff
than those in commerical fertilizer. In addition, problems with other
fertilizers may occur (an inherent difficulty is determining nutrient
content of the wastes and nutrient release to the soil). Another
problem may exist with heavy metals in municipal waste when applied on
cropland.
The development of biological nitrogen-fixation (213) is expected to
have far reaching effects on crop production in the future. Expected
developments include ways of using nitrogen more efficiently, means
of increasing the nitrogen fixing by plant micro-organism, and methods
of improving symbiotic relationships between plants and micro-organisms.
Also, genetic developments are anticipated in introducing nitrogen-fixing
capabilities into non-legume plants requiring high applications of ferti-
104
-------
lizers such as corn. With such nitrogen fixation developments considerable
reductions in fertilizer use would occur. This would reduce potential
nitrogen runoff and leaching.
A number of developments in improved fertilizers (214) are expected to
occur in the future which will have major effects on practices in
nutrient management. Controlled-release fertilizers will decrease the
runoff potential of nitrogen into surface water and will decrease the
eutrophication in those waters that do receive nutrient loading from
fertilizers applied to cropland. Additionally, this development will
increase the efficiency of nutrient intake of crops which will reduce
the amounts of nutrients available for runoff and leaching. Development
of nitrification and leaching inhibitors will reduce problems associated
with contamination of ground water. These collective trends in nutrient
management (other than the increasing use of fertilizers) are expected
to have an overall beneficial effect on the environment.
(d) Pest control trends. Trends in pest control include improved
methods of application, scouting, developments in new pesticides,
resistant crops and biological controls. Scouting ( 215) both surface
and by remote sensing, is expected to reduce overall pesticide use by
reducing the requirements for continued application in areas in which
there is no threat of pest infestation.
Recent improvements in application practices (216) are expected to have
beneficial effects. Improvements in aerial application techniques will
reduce the amount of pesticides applied to non-target areas with a
consequent reduction in pesticide use and a greater efficiency of
application. These improvements will result in an increasing share of
all pesticides being applied by aircraft. Also, the increasing use of
floaters not only promotes efficiency in the application of pesticides,
but also facilitates more timely applications. The combined effects of
these improvements will be a reduction in pesticide requirements. In
addition to the reductions in potential pesticide pollution, a slight
reduction in soil erosion will be associated with the floater application.
Developments in dual application of fertilizer and pesticides will carry
both favorable and unfavorable implications. Dual application decreases
the movement of vehicles across the cropland which would lessen somewhat
the disturbance of the soil. However, applications under this technique
are generally not optimal for both fertilizer and pesticide use. Con-
sequently, one of the two would be subject to runoff for a period of time
greater than necessary.
Reductions in requirements for pesticides are expected with developments
involving more resistant crops (217). The most beneficial developments
are anticipated in the area of new improved crops resistant to pests such
as insects, nematodes, birds, plus diseases. Although no dramatic develop-
ments are foreseen on the horizon, gradual improvements are envisioned
which will alleviate some of the potential pesticide problems.
105
-------
New pesticides (218) are being developed which will have environmental
implications. They include formulations such as micro-encapsulated and
systemic pesticides. The benefits from these will be derived from their
greater efficiencies and the associated reduction in the total level of
pesticides required. Surfactants for herbicides will facilitate more
timely applications and the use of alternative pesticides. Significant
impacts are expected with developments of biodegradable pesticides. These
will reduce both the contamination of water (surface and ground) and of
the soil itself.
Developments in biological control ( 219) are expected which will also have an
influence on pest control practices. Potential developments involve the
use of juvenile hormones, pheromones, sterile males, predators, and para-
sites. Both beneficial and adverse effects may occur with these develop-
ments. Biological control, in some cases, would decrease the requirements
for pesticides on specific crops. This, of course, would reduce potential
pollution problems: however, the introduction of these biological controls
could have potential damaging effects on the environment if they affected
non-targeted plants or beneficial insects.
Developing integrated controls (220) is generally the most effective
system of pest control. In many cases it benefits the environment by
facilitating reductions in pesticide use.
(e) Resource use trends. The trends discussed above were viewed in
light of impacts which were expected to occur from changes in practices
as utilized on a single unit of cropland. In many cases the practices
involved changes in the use of resources such as land, pesticides, and
fertilizer. Collectively these practices may be expected to have signi-
ficant effects on resource use and hence on the environment, although
the trends with an overriding importance are those of the increasing
levels of agriculture inputs associated with the increasing demand for
food. The inputs that pose significant environmental implications are
fertilizers, pesticides, and land. By the year 2010, the use of ferti-
lizers and pesticides is projected to increase well over a 100 percent
while land required for nonirrigated cropland is projected to increase
by fifteen percent. These increases, which constitute the basic forces
on the environment, bring into focus the fundamental problems involving
water, air, and land pollution. All of the practices and developments
previously identified must be viewed in this perspective.
106
-------
SECTION VIII
ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVICULTURAL TRENDS:
PANEL 3 - FEEDLOT PRODUCTION
The Feedlot Production Panel assessed and ranked the major environ-
mentally related trends and practices in its area of expertise.
The preliminary report of trends and practices in this panel area,
as shown in Part C: "Background Summary", below, was the principal
basis for the evaluation. The trend rankings by the Feedlot Production
panel are as presented in Exhibit VIII-1; and, Exhibit VIII-2 describes
briefly the top ten trends and the panel's rationale for establishing
the relative rankings as indicated. Furthermore, the panel's exten-
siveness of use and intensiveness of effects ratings for each subtrend,
which were used to develop the overall environmental rating for each
trend, are presented in Exhibit III-3. These exhibits are described
further below.
The Feedlot Production panel assessed, in particular, beef, dairy,
swine, sheep and poultry. This panel's assessment was limited to
feedlot activities, and specifically excluded livestock maintained
on range or pasture land (which was considered by Panel 4--Range and
Pasture Management).
The panel was comprised of five members with diverse capabilities and
professional training. A wide geographic area was represented by these
panelists.
Name
Raymond C. Loehr
James K. Koelliker
Dan D. Badger
B. P. Cardon
D. E. Becker
Representing
Cornell Univ.
Specialty
Agr. Engineer-
Waste Disposal
Treatment
Oregon St. Univ. Agr. Engineer-
Waste Disposal
Okla. St. Univ. Agr. Economics
Arizona Feeds
Univ. of 111.
Feedlot Produc-
tion
U.S. Geographic
Area
Northeast
Northwest
South-Midwest
West
Animal Science Midwest
107
-------
Exhibit VIII-1. Ranking of environmentally-related trends, 1976-2010:
Feedlot Production
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
Trend ,
Number -
308
319
317
313
318
309
316
301
314
307
303
304
310
,, Adjusted
- Trend Rating
Feedlot Sizes
Feedlot Design for Waste Management
Feedlot Residual Disposal - Solids and Liquids
Odor Control
Increased Feed Efficiency and Alternative
Ration Composition
Geographic Concentration
Increasing Pesticide Use
Improved Animal Breeding
Dust and Pest Control
Veterinary Services
Improved Birth Control
Alternative Bedding Material
Specialization, Mechanization and Use of
Multiple Man Units
15
12
10
9
8
8
6
6
4
2
<2
<2
<2
' Numbers are those trend numbers given in Phase I, Interim Report.
108
-------
Exhibit VIII-2. Descriptions of major environmentally-related
trends, 1976-2010: Feedlot Production
Adjusted Rating
Rank Trend Number and Title for 2010
Comments and Modifications
1 308 - Feedlot Sizes
15
2 319 - Feedlot Design for 12
Waste Management
3 317 - Feedlot Residual Dis- 10
posal - Sol ids and
Liquids
4 313 - Odor Control
5 318 - Increased Feed Efficiency 8
and Alternative Ration
Composition
6 309 - Geographic Concentration 8
7 ,316 - Increasing Pesticide Use 6
8 301 - Improved Animal
Breeding
9 314 - Dust and Pest
Control
All classes of livestock will
use new and larger feedlots
and they will select environ-
mentally preferred sites and
use better controls as the
number of smaller feedlots
decrease,
Feedlots would continue to im-
prove facilities and management
practices which would enhance
the environment. The trend will
be accelerated by construction
of new and larger size feedlots.
Utilizing these management
practices will reduce the
environmental problems of
feedlots--each class of
livestock may select different
practices.
The trend towards improved
waste management is most
Important for odor control.
Roughage usage is relatively
unimportant in this trend,
chemicals used to enhance
animals utilization of feeds
Is of moderate importance.
Little change 1n geographic
distribution is expected and
adequate environmental con-
trols will be utilized.
There will be increased but
better managed use of pesti-
cide at the feedlot.
Increased use by producer is
expected to achieve better
feedlot gains to reduce
grain consumption and wastes
per unit of production.
Small but improved fly, dust
and rodent controls are
foreseen.
10 307 - Veterinary Services
Death losses will be lower
and feedlot gains will be
higher, but only small changes
1n practices are expected.
109
-------
A. Major Trend Rankings and Practices Assessments
The process of evaluating environmentally related trends for U. S. feed-
lots revealed that none of the trends would cause tremendous environment-
al changes over the next 35 years. The range of scores for any particular
trend was allowed to go as low as a negative 25 and as high as a positive
25 under the chosen rating system. The range in scores for all manage-
ment practices and trends-was between a negative eight and a positive 15.
Consequently, it appears that the trends and practices evaluated by the
feedlot production panel were considered to have only moderate or minor
effects on the 2010 environment.
Several generalizations could be made concerning feedlot effects on the
environment in the year 2010. Feedlots in 2010 are expected to cause
less environmental degradation than feedlots currently may cause. This
conclusion is primarily due to the relatively new emphasis on waste
handling practices as an important managerial variable. Future feedlots
will consider waste management as part of their normal activity. The
most important future changes which are expected to occur are that the
size distribution of feedlots is expected to shift towards larger lots
and the land base associated with the feedlots is expected to decline.
This implies that feedlots of the future will be less likely to be of
the farmer-feeder type. In addition, trends which reduce the quantity
of feedlot wastes are considered about as equally important as trends
which improve waste disposal techniques.
All classes of livestock are expected to utilize new and larger feedlots.
This expansion in feedlot size was expected to occur only at environment-
ally preferred sites where surface water runoff and odor problems can be
minimized. Feedlots are expected to adjust their facilities either as
they expand or as they attempt to comply with environmental regulations.
Surface water runoff control facilities and total confinement facilities
are expected to be more numerous.
The complete feedlot panel ratings are shown in Exhibit VIII-3. The
1976, 1935, and 2010 extensiveness of use in ratings of all subtrends are
included. The intensiveness ratings were determined for the year 2010
only; they are also included in Exhibit VIII-3.
The three feedlot trends which were expected to have the greatest environ-
mental effect are:
1. Feedlot Sizes (308)
2. Feedlot Design for Waste Management (319)
3. Feedlot Residual Disposal - Solids and Liquids (317)
110
-------
Exhibit VIII-3. Environmental ratings of ten trend", and associated
practices: Feedlot Production
Rank
1
2
3
4
5
6
7
a
9
10
Trend
No. Trend and Sub-Trend
308
319
317
313
318
309
316
301
314
307
Size of Feedlots
a. Beef
b. Dairy
c. Swine
d. Sheep
e. Poultry
Feedlot Design for Waste
Management
a. Open lot
b. Dry lot
c. Total confinement
d. Retention ponds
e. Diversion terraces
f. Settling basins
g. Lagoons
h. Oxidation ditch
1. Storage pit
Feedlot Residual Disposal -
Solids and Liquids
a. Dally disposal
b. Temporary storage of solids
c. Off-site disposal of solids
d. On-site disposal of solids
e. Refeeding of solids
f. Liquids disposal
Odor Control
a. Feedlot animals
b. Waste management
Increased Feed Efficiency and
Ration Composition Adjustments
a. Ruminants
b. Non- ruminants
c. Roughage usage
d. Concentrate usage
Geographic Concentration
a. Beef
b. Dairy
c. Swine
d. Sheep
e. Poultry
Increasing Pesticide Use
Improved Animal Breeding
a. Artificial Insemination
b. Cross breeding
c. Breed selection
Dust and Pest Control
Improvement
a. Feedlot flies
b. Rodents and dust
Veterinary Services
a. Prenatal lumunization
b. Vaccines and antibiotics
c. Consulting veterinary
Intenslveness
Extenslveness Trend Rating Rating
1976
3
2
3
3
4
2
3
2
2
2
5
2
4
1
1
1
2
5
3
1
4
4
4
4
4
4
2
2
3
1
1
2
1
4
2
1985
4
3
4
3
5
2
2
3
2
2
2
2
1
3
2
5
3
3
1
2
1
3
5
3
2
4
4
4
4
3
4
3
3
4
2
1
3
1
4
2
2010
5
4
5
3
5
2
2
4
4
4
4
2
1
4
2
5
4
2
,
3
2
4
5
4
2
4
4
4
4
3
4
4
4
5
2
2
3
\
4
2
2010
+3
+3
+3
+3
+3
-2
-1
+2
+2
+2
+1
-1
+1
+1
+1
+2
+3
+3
+3
+3
+2
+3
+2
+2
-2
-2
+2
+2
+2
+2
+2
>2
+1
+1
+1
+2
+2
+1
+3
+1
m
-------
These three trends were expected to be inextricably woven together in
their development. As feedlots increase in size, the expanded portion
of a feedlot or any new facility is expected to incorporate recommended
facility designs and to utilize alternative residual disposal methods.
Although these three trends could be viewed as separate and distinctly
different, it was expected by the panel members that the three trends
will develop together.
B. Environmental Implications of Major
Trends and Practices
Each of the major trends in feedlot production, as determined by
Panel 3, are summarized below. Background descriptions and definitions
of these trends, which served as the basis for the workshop's evalua-
tions, are included for reference in Part C: "Background Summary",
as needed.
Feedlot Sizes (308). The trend toward larger feedlots, generally only
now beginning, will have the most important environmental implication
for feedlot production. Only a moderate beneficial effect is expected
to occur as feedlots increase in size. Beef, dairy, and swine feedlots
are considered to be moderate in size-extensiveness, but by 1985 the
trend will be important in extensiveness. Sheep feedlots are not ex-
pected to change substantially in size, and poultry facilities are al-
most through their trend towards larger sizes.
The feedlot panel deliberated between evaluating the size trend by the
number of feedlots or by the quantity of production from those feedlots.
The decision was to evaluate this trend relative to the number of lots
rather than to the proportion of production from each size of feedlot.
Increased feedlot size was considered the most environmentally important
trend because of the adjustments which it will require. As feedlots
increase in size, their economies are generally enhanced in two ways.
First, their capital outlay per head for abatement facilities is consider-
ably less, about one-fourth, for a large (1000+) feedlot as compared to
a smaller (200-500 head) feedlot. Second, their financial resources are
also greater. Larger feedlots will then use a smaller proportion of
their financial resources to obtain proper waste facilities.
Additionally, as feedlots increase in size, they will do so in environ-
mentally preferred locations. Producers have been made aware of the
possibility of legal problems and the associated financial risks of locat-
ing or expanding feedlot facilities near streams and population centers.
Over time, as current producers retire and as environmental regulations
and enforcement procedures are developed, feedlots located in environ-
mentally sensitive areas will phase out of production.
112
-------
Feedlot Design for Waste Management (319). This particular trend was
derived from a combination of preliminary report trends 306, 311, and
312 (see, Part C), including those for housing facilities, feedlot
runoff control structures, and several waste handling methods. These
are separate variables which management may combine in several ways,
and since no precise logical separation of these variables seems
appropriate, the panel combined them into one trend. The use of open
and drylot I/ feedlot facilities were expected to remain at current
use levels or decline slightly between 1976 and 2010. Continued use of
open lots and drylots will cause a minor adverse impact on the environ-
ment; however, legal statutes and pollution control technologies will
importantly affect the trend.
Totally confined feedlots are expected to increase from a limited use
level to a relatively important use level by 2010; however, considerable
controversy existed among the panel members over the environmental impli-
cations of totally confined feedlot facilities. A trend toward total con-
finement facilities is considered beneficial since feedlot runoff poten-
tial should be reduced. The adverse environmental aspect of this trend
was concerned primarily with totally confined swine facilities. Air de-
gradation due to odors was not completely assessed, but it was generally
thought to be caused by improper management practices. It was not de-
termined whether the management practices associated with the totally
confined hog facility were constrained by managements knowledge of proper
operating procedures or by other factors such as limited land disposal
opportunities due to crop production or legal regulations.
The use of runoff control facilities such as settling basins, retention
ponds and diversion terraces was relatively limited in 1976. By 1985,
the number of feedlots using these facilities will increase from a minor
use level to a limited use level, and by 2010 their use would be relative-
ly important. This predicted growth is consistent with that for open
and drylot facilities and the assumption of enforced legal statutes.
Other waste handling facilities such as lagoons and oxidation ditches
will be adopted by relatively few feedlots. The use of storage pits
should double by 2010, primarily by swine feedlots.
Feedlot Residual Disposal - Solids and Liquids (317). The proper
and effective use of waste disposal methods including those other
than the traditional waste handling practices are expected to cause
some improvement in the environment.
I/ See Part C: "Background Summary", for definitions of management
variables and practices.
113
-------
Three general predictions about solid waste handling practices resulted
from the panel discussions. The use of daily and temporary storage V
of solid wastes will not change over the next 35 years. The major change
expected in solid waste disposal is that off-site or off -farm disposal
and it will be important in 2010. Conversely, on-site disposal would
be subsequently reduced comparably. Refeeding of animal wastes is con-
sidered of very minor importance today and in 1985, but by 2010, refeeding
will be of moderate importance for feedlots.
Since it was assumed that legal requirements will effectuate the proper
disposal of wastes, the environmental effect of this trend is definitely
beneficial. (This trend was trend 315 in the contractor's preliminary
report.)
Odor Control (313). Improvements in odor control by feedlot managers
will enhance our current environment. A gradual increase in the number
of feedlots employing waste odor control will continue until 2010, when
a substantial (important) number of feedlots will employ these practices.
Increased Feed Efficiency and Alternative Ration Compositions (318).
Considered one of the five most important environmentally related trends
in feedlot production, this trend's evaluation is complicated by its
having both beneficially significant and adversely significant effects.
Its beneficial effects are derived from practices which improve or main-
tain high grain.- to -feed rations. Feed efficiency reduces the feedlot
industry's demand for feed grains and, consequently, decreases its waste
materials. Feed efficiency for ruminant animals is extensively sought
by a significant proportion of these feedlots. It was believed, however,
that in the aggregate, feedlots with non-ruminant animals can improve
their feed efficiency from a current moderate level of significance by
2010.
The ration composition of feedlots will probably result in an adverse
environmental trend. If high roughage rations are used, and it is
believed that their use will increase by 2010, longer feeding periods
will result. Consequently, as each animal requires more feed, its
waste materials will increase too since longer feeding periods will also
be required, feedlot space will increase. If high concentrate rations
are used in 2010, the increased grain demand due to increased cattle
numbers will add pressure in increased cropland production. It was
generally believed that high concentrate rations would not be used
by a larger proportion of the feedlots in 2010 than in 1976, but the
number of feedlots using a high roughage ration will increase. (This
trend combined, for ease of discussion, preliminary report trends
302 and 305.)
-/ Temporary storage in the context of panel discussion implied close
covered or contained storage, not solid wastes remaining where deposited.
114
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Geographic Concentration (309). This particular trend received a
moderate level of importance for the environment, relative to other
feedlot production trends. All classes of feedlot livestock, because
of regional production concentrations, already have a relatively high
level of concentration. Too, since adequate land will be available in
2010 and current legal statutes for waste management practices will
presumably be fully implemented, this trend will not adversely affect
the environment. No change in geographic distribution for the major
proportion of feedlot livestock was foreseen.
Increasing Pesticide Use (316). A trend towards increasing pesticide
use is expected over the next 35 years. Although pesticide use by
feedlots would probably double by 2010, no adverse environmental effect
is expected. The application of insecticides to and around livestock
has been regulated by the USDA and the Federal Food and Drug Administra-
tion for several years; consequently, adequate pesticide management
should exist in 2010. In addition, the use of pesticides will increase
the feed efficiency of livestock and, subsequently, reduce feed demands
and waste disposal requirements.
Improved Animal Breeding (301). Improved animal breeding should enhance
the environment in 2010.Artificial insemination and cross breeding will
nearly double over the next 35 years and will, in turn, increase feedlot
efficiency. Two of the basic assumptions behind this conclusion are that
considerable gains in estrus control will occur, and artificial insemina-
tion will increase in popularity.
Dust and Pest Controls (314). A minor improvement in the 2010 environ-
ment is expected to result as the number of feedlots using available
controls increase slightly.
Veterinary Services (307). This trend is the tenth most important en-
vironmentally related feedlot trend. Prenatal immunization and the use
of consulting veterinary services were not considered to have anything
more than very minor significance in the future. Vaccines and anti-
biotics will be of major significance today and in the future. By
itself, this subtrend ranked nearly equal to the subtrends of the most
important environmental feedlot trend. The beneficial effect of the
decrease in death loss and in diseased feedlot animals was evaluated
relatively high by the feedlot panel members.
C. Background Summary
The following descriptions and definitions of trends and management
practices (subtrends) in feedlot production were provided to the work-
shop participants as background for the workshop evaluation. In some
cases, the panel members chose to re-group selected subtrends or add/
delete subtrends as noted. As such, this summary is quasi-independent
115
-------
of the workshop results as presented in Parts A and B, above. However,
this summary provides appropriate background base data, definitions,
and descriptions of the trends and practices assessed in this portion
of the total study.
1. Overview and Base Data
Livestock production has a substantial financial and regional impact on
the agricultural sector. Between 1971 and 1973, livestock products pro-
vided over half of the cash receipts to farmers, and two-thirds of these
came from the sale of red meat animals. Many of these received grain or
concentrates in a feedlot prior to being marketed. The geographic concen-
tration of livestock production was shown in Exhibits VIII-4 to VIII-8.
The feedlot industry was defined to be consistent with the intentions of
the Environmental Protection Agency. Any livestock operation which has
a "concentrated confined animal and poultry growing operation for meat,
milk or egg production, a stabling in pens or houses wherein the animals
or poultry are fed at the place of confinement and crop or forage growth
or production is not sustained in the area of confinement" is considered
part of the feedlot industry.
The feedlot industry is very diverse. It is geographically dispersed; it
is composed of several classes of livestock produced in a variety of
facilities; it utilizes facilities which vary from merely fenced pasture
land to totally confined housing units. The economic base and the owner-
ship structure account for many of the differences found in the Feedlot
Industry.
Beef Feedlots. Beef feedlots exist in almost every state of the United
States and are predominate in the Midwest and West. Feedlot growth is
occurring in the Southeast. Feedlots vary in size, in facilities and in
economic importance.
The major type of beef feedlots is classified as farmer-feeders with less
than 1,000 head capacities. Approximately 98 percent of all feedlots
produced fewer than 1,000 head, but they marketed only 35 percent of the
fed cattle in 1974. Nearly three-fourths of all feedlots produced fewer
than 100 head of fed beef.
Beef feedlots range in size from just a few head to thousands of feeders.
There has been a general trend toward larger and larger feedlots, and
each year the number of smaller feedlot categories have decreased while
the production from larger feedlots has steadily increased. There has
also been a regional shift in beef feedlot production which has accom-
panied this growth in feedlot size. As feed grains become readily avail-
able in the South and West, many large feedlots are constructed to utilize
the new feed source at its production site.
116
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Exhibit VIII-4. Cattle fattened on grain and sold for slaughter. Each dot represents
5,000 head.
IMi CtHSutOf ACMtCVlTUftl
Oir*«TlilNT (X GOMMIMCI
ANG ICDNOMiG JTfcTrSTtCJ AO**iNIIT«*TC
•UKIAU or THI ciwtm
-------
Exhibit VIII-5. Milk cows. Each dot represents 1,000 milk cows.
-------
Exhibit 1/III-6. Hogs and pigs. Each dot represents ?0,000 hogs
-------
Exhibit VIII-7. Broilers and other meat-type chickens. Each dot represents
500,000 chickens.
a
-------
Exhibit VIII-8. Chickens 3 months old or older. Each dot represents
50,000 chickens.
ro
'Mi CfXSUt Of AGHIOJLTUM
OfPAftTlflMT Of COMMIHCI
IDCtAL AM) ICDMOMIC 1TATIITICS ADHIMItTIUTlC
•UNCAU Of THI CtNtUi
-------
Many of the new and larger feedlots have adopted the traditional Western
feedlot facility design—open feedlots with unpaved surfaces and little
or no shelter. The major facility change has been the addition of feed
processing equipment. In the eastern half of the United States, beef
feedlots have partial housing facilities with mostly unpaved feedlot
surfaces. Only two percent of the Eastern feedlots are totally confined
facilities.
Swine Feedlots. Hog production is concentrated in the North Central and
Southeastern states. The Corn Belt-Lake States have generally produced
nearly two-thirds of the total U.S. hog production with Iowa and Illinois
alone producing one-third of the U.S. hog production. Often cattle feed-
ing and hog production will occur on the same farm.
Many hog producers are farmer-feeders. Seventy-five percent of all hog
producers in the 15 major hog producing states sell fewer than 200 hogs
per year. This industry has long been noted for its rapid change of pro-
duction levels as many small producers with other sources of agricultural
income react to hog and feed grain prices. Commonly,hog feeders enter
and exit hog feedlot activities more rapidly than do other livestock
feeders.
Housing facilities for hog production vary considerably. Nearly half of
the farms selling hogs in the 15 major hog producing states use open lots
with partially paved or unpaved lots. One-third of the farms use pasture
lots, and nearly 13 percent use paved lots. About eight percent use
totally confined facilities. The incidence of total confinement facili-
ties increases as the quantity of hogs sold increases. Nearly half of
the producers with lots in excess of 1,500 head capacities use totally
confined facilities, but fewer than five percent of the hog feedlots
under a 100 head capacity use total confinement.
Dairy Feedlots. Dairies are heavily concentrated in the Southeast, the
Northeast and California. Most dairy farms will produce a major part of
their feed requirements. This usually involves production of a high
proportion or all of their pasture and silage requirements and most of
their feed grain and hay needs. The degree of production of these feed-
stuff does vary regionally within the United States. California has
been the major exception where large dry lot producers purchase nearly
all of their feed and replacement livestock.
The number of dairy feedlots has been declining rapidly. Between 1964
and 1973, the number of dairy feedlots decreased 70 percent. Small dairy
farms (30 or fewer milk cows), however, have remained viable and consti-
tute over half of the dairy producers. Only seven percent of the dairy
farms were estimated to have 100 cows or more.
All phases of milk production technology have substantially changed over
the past few decades, including milking methods and milk handling. Milk-
ing machines have replaced hand milking. Bulk milk handling and storage
facilities have been widely adopted. The milking facilities have also
changed and are classified under three general groups:
122
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. Stall barn with milk room - partially or totally
covered facilities
. Free stall barn with milking center - partially or
totally covered facilities
. Cow yard with milking center - open lot system.
Partially housed dairy facilities are predominant across all regions of
the United States.
Poultry Feedlots. Confined turkeys, ducks, and broilers are considered
parts of the poultry feedlot industry. The turkey industry, a highly
concentrated industry has relatively few growers, and these are located
in limited geographic areas. Turkey production is widely scattered
throughout the United States, but there is a concentration of turkey
producers in Minnesota, California, North Carolina, and Missouri. Duck
production is largely held in the hands of proprietorships and close
held family corporations which specialize in duck production. In 1973,
there were only 65 production locations for ducks. Broiler production
occurs within highly integrated production systems. Most broiler pro-
duction occurs in the Southeast, East, and California in large confined
facilities.
Turkey. All turkeys are started in brooder houses for the first eight
weeks of production. The turkeys are then moved to a feeding operation.
First, and still the dominant type of operation, is to feed them on
fenced pasture land with portable feeders and waterers. The feeding
area is moved about the pasture, for the intense concentration of birds
near the feeding and watering area generally tramples the grass into
barren land.
Duck. Ducks are raised in confined areas until they reach a slaughter
weight between five and seven pounds, normally about seven weeks after
hatching. Generally seasonal, duck production primarily occurs between
March and December. Production activity is often supplemented by the
care and maintenance of the brood flock which is usually kept for 12 to
18 months prior to their disposal. Those producers with totally con-
fined housing facilities operate on a year around basis.
About half of the 65 duck feedlots produce between 15,000 and 55,000
ducks per annum, while one-fourth of the duck feedlots are below and
one-fourth are above this production range. Generally, the number of
producers have tended to decline in the under 15,000 head capacity size
group. Total production has been relatively constant since 1962 with
production ranging between 9 million and 11 million birds annually.
There are three major types of duck production facilities: wet lots,
dry lots, and total confinement. Wet lots allow the ducks to have ac-
cess to swimming water. Dry lots provide only drinking water for the
ducks. Confined facilities utilize a litter over a solid surface and
flushing troughs. It was estimated that nearly four-fifths of the duck
feedlots are wet lots and about one-fifth are totally confined facilities,
123
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Broiler. The concentration and efficiency of the broiler industry have
increased consistently since the depression as the industry has changed
from small, widely scattered production units to a large, concentrated
industry. Over four-fifths of the broiler production is concentrated in
ten states. In addition, 95 percent of the production is either grown
under contract or vertically integrated into the entire feeding, processing,
and marketing structure of large firms.
Broilers are usually raised in confined facilities using a floor litter
system. In about eight weeks time, the broilers are slaughtered as they
approach a weight of four pounds.
Nearly five percent of the broiler chicken population is breeder stock
kept in totally confined facilities with nesting material, litter covered
floors, and slatted or wire covered perches built over pits.
Sheep Feedlots. Sheep feedlots are primarily (80 percent) located in the
Western region of the United States and about one-fifth of the sheep feed-
lots are in the Midwestern Corn Belt States and New York. In the Western
region, nearly two-thirds of the feedlots have the capacity to feed between
1,000 and 5,000 head; of the remaining forty percent of the feedlots, about
half are below and half are above this 1-5 thousand feedlot size group.
Open feedlots are the predominate housing facility.
*/
2. Trends and Environmental Implications —
The feedlot industry encompasses a wide variety of livestock which are
geographically dispersed. Consequently the environmental implications
are expected to differ among geographic regions. The major aspect common
to this very diverse industry is that livestock production will increase
substantially by 2010. The management practices which prevail in the
future will ultimately determine the environmental impacts of this in-
creased production.
Trends. The general agricultural trend between 1972-74 and 2010 is one
of increasing production. The projected farm output index is expected
to increase from 110 to 166. Within the livestock sector, production
is expected to increase for all classes of livestock except sheep. The
output projections for each livestock class is shown in Exhibit VI11-9.
below.
*/
— Though not of substantive concern affecting trend rankings and
practice assessments arrived at in this study, major trend cate-
gories discussed in these base data were in some cases regrouped
to facilitate workshop panel discussion. These changes are as
follows:
Base Data Categories became Revised Categories
315 317
302, 305 318
306, 311, 312 319
124
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Exhibit VIII-9. Livestock production projections
Million Ibs. Produced Percentage Change from 1972-74
Commodity 1972-74 1985 2010
Beef and Veal
Pork
Chickens
Milk
Lamb and Mutton
22,669
13,384
9,028
1,169
509
+ 32
+ 18
+ 33
+ 4
- 62
+ 75
+ 49
+ 79
+ 9
- 60
The manner in which the feedlot industry increases its production will
have an important affect on the environment. Without prejudging the
positive or negative affect of this projection for increased production,
the overall intent is to identify current or future feedlot trends which
may be used to achieve the projected production goals.
The major feedlot practices which were expected to have some environmental
implication were first initially identified by using a systems approach
to feedlot production which is illustrated in ExhibitVIII-10. Aggregate
groupings were identified according to science and technological develop-
ments, which were: animal science, agricultural engineering, veterinary
science, and economics. Trends within these aggregate groupings were
identified and are shown in Exhibit VHI-lland subsequent descriptions
are included in Exhibit VIII-12.
The overall number of feedlots are expected to be reduced by at least 50
Percent by 2010. This decrease in feedlots and increase in production
(i.e. increased size concentrated) is shown in Exhibit VIII-13.
•Environmental Implications. The feedlot industry trends which have been
identified and described are expected to impact on the environment by
either affecting the total quantity of wastes or the concentration of
inputs and/or residual factors.
(a) Animal Science Trends. Five specific trends from the Animal Science
research were identified: animal breeding, feed efficiency, birth controls,
bedding material, and ration formulation.
improved animal breeding (301) provides the potential to increase pro-
ductivity per animal. Artificial insemination, cross breeding, and
breed selection can impact the environment in two respects: the number
of animals required to produce a given output level should decrease and
the associated fecal matter should decrease.
Improved feeding efficiency (302) has several possible implications. Feed
efficiency, p_e_r_ se_, will reduce feed consumption, thus reducing the crop-
125
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Exhibit VIII-10. Livestock production system (feedlots)
OUTPUT
OUTPUT
A
SEDinCNT
1 i
IWTIIIEKTS
PESTICIDES
i
BIOOLSHAD-
A8LE
CRunics
A
1IGBGA.SIC
SALTS t
NKKALS
a 1
HASTE
HATH
AIIIHAL
HASTES
1
AN::«L
MCDUCT
1
PATHOCENS
land production demands and livestock fecal production. Increased use
of high cellulose feeds due to processing or chemical treatments will
also reduce the grain consumption demands of livestock but it will in-
crease the quantity of livestock wastes. The use of non-conventional
feeds by non-ruminants would reduce grain consumption and possibly reduce
aggregate livestock wastes for disposal to croplands.
The use of implants is known to increase feed efficiency but it is also
suspected to be hazardous to human health.
Improved birth control (303) could drastically reduce the livestock brood
herd requirements as much as fifty percent. This has several environ-
mental implications. To achieve brood herd reductions, the brood herds
may have to leave the traditional dispersed pasture or range setting
and shift to concentrated feedlots to obtain the necessary birth control.
Although feed consumption would be reduced, it may mean an increased con-
centration of animals.
126
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Exhibit VIII-11. Environmentally-related trends in
agriculture: Feedlot Production
ANIMAL SCIENCE TRENDS
301. IMPROVED ANIMAL BREEDING
a. Artificial insemination
b. Cross breeding
c. Breed selection
302. IMPROVED FEEDING EFFICIENCY-/
a. Ruminants: non-protein nitrogen, rumen fermentation,
chemical treatment of forage and crop residue, lipids,
processed grains and by-products,
b. Non-Ruminants: fish protein, single cell protein, leaf
protein,
c. Chemicals: DES, Zeranul, Synonex appetite stimulants
303. IMPROVED BIRTH CONTROL
a. Hormone implants
b. Estrus control
c. Multiple births
304. ALTERNATIVE BEDDING MATERIAL
(straw)
(sawdust)
(other)
305. ALTERNATIVE RATION FORMULATION-/
a. High roughage ration
b. High concentrate ration
c. Other
AGRICULTURAL ENGINEERING
306. ALTERNATIVE FACILITY DESIGN-/
a. Open lot
b. Dry lot
c. Total confinement
VETERINARY SCIENCE TRENDS
307. VETERINARY SERVICES
a. Prenatal immunization
b. Vaccines and antibiotics
c. Consulting veterinary services
127
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Exhibit VIII-11 (continued)
ECONOMIC TRENDS
308. INCREASED SIZE OF FEEDLOTS
a. Beef
b. Dairy
c. Swine
d. Sheep
e. Poultry
309. INCREASED GEOGRAPHIC CONCENTRATION OF FEEDLOTS
a. Beef
b. Dairy
c. Swine
d. Sheep
e. Poultry
310. INCREASED SPECIALIZATION, MECHANIZATION AND USE OF MULTIPLE MAN UNITS
a. Vertical integration
b. Single enterprise firms
WASTE MANAGEMENT TRENDS
*/
311. FEEDLOT RUNOFF CONTROL'
a. Retention ponds
b. Diversion terraces
c. Settling basins
312. LIQUID WASTE CONTROL-''
a. Lagoons
b. Oxidation ditch
313. ODOR CONTROL
a. Feedlot animals
b. Waste management
314. DUST AND PEST CONTROL
a. Feedlot
b. Feed preparation
315. SOLID DISPOSAL-7
a.
_. Temporary storage
c. On site or farm
d. Off site or off farm
PESTICIDE DEVELOPMENT TRENDS
316. INCREASING PESTICIDE USE (chlordane, aldrin, etc.)
Trend changes were made by the evaluation workshop as noted in
Subsection C-2: Trends and Environmental Implications.
128
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Exhibit VIII-12. Description of environmentally-related trends and
developments: Feedlot Production
ANIMAL SCIENCE TRENDS
301. IMPROVED ANIMAL BREEDING
a. Artificial insemination: Use of stored semen for increasing
the number of progenyfrom genetically superior males
b. Cross breeding: Mating different breeds of livestock to
achieve desired breed characteristics and hy-bred vigor
in the offspring
c. Breed selection: Developing the desired characteristics
of particular livestock breeds
302. IMPROVED FEEDING EFFICIENCY^
a. Ruminants: The addition of chemicals to feedstuffs will
enhance the nutritive value obtained from roughage and
other high fiber content feed
b. Non-ruminants: Capable of utilizing non-conventional
feedstuffs and animal wastes --reduce grain demands
c. Chemicals: The implanting or feeding of chemicals which
enhance, the consumption or feed conversion capabilities of
livestock - increased feed efficiency is near 11 percent
303. IMPROVED BIRTH CONTROL
a. Hormone imp!ants: Affect litter size -(?.s much as 84
percent in swine;
b. Estrus control: Greatly improves the efficiency of arti-
ficial insemination by the use of chemicals (Prostsqlandin
F2 )
c. Multiple births; Increased number of offspring by drug
treatments
304. ALTERNATIVE BEDDING MATERIAL - Dry matter added to the
feedlot to absorb moisture and odor
305. ALTERNATIVE RATION COMPOSITION ^
a. High roughage ration; Feedstuffs have a high cellulose
content which causes a lower rate of gain and longer feeding period
b. High concentrate ration: Feedstuffs having relatively
high energy content per unit.and higher rates of gain
129
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Exhibit VIII-12 (continued)
AGRICULTURAL ENGINEERING TRENDS
306. ALTERNATIVE FACILITY DESIGN*/
a. Open lot: Feedlots with no roofed shelters and no paved
surfaces except limited areas in front of feed bunks
b. Dry lot: Feedlots with roofed structures and paved or
unpaved surfaces
c. Total confinement: Feedlots with either cold-covered
shelters enclosed or at least three sides or warm-enclosed
shelters
VETERINARY SCIENCE TRENDS
307. VETERINARY SERVICES
a. Prenatal immunization: Pre-birth innoculations to produce
disease-free livestock at the time of birth
b. Vaccines and antibiotics: Innoculations to reduce death
losses and maintain or improve feedlot gains
c. Consulting veterinary services: Routine use of veterinary
skills to improve herd health - only 30 percent of initial
disease occurrence is treated by veterinarians
ECONOMIC TRENDS
308. INCREASED SIZE OF FEEDLOTS - Among most classes of livestock
production is increasing and the number of feedlots are
decreasing - exception is sheep. (See Exhibit IV-C 10)
309. INCREASED GEOGRAPHIC CONCENTRATION OF FEEDLOTS - The location of
specific feedlot types have become more concentrated in par-
ticular regions - see Exhibits IV-C-1 to 5
310. INCREASED SPECIALIZATION. MECHANIZATION, ANJ5 USE DF MULTIPLE
MAN UNITS - An increase in the concentration of man
power and machinery has resulted f^om the growth in large
feedlots
WASTE MANAGEMENT TRENDS
311. FEEDLOT RUNOFF CONTROL
a. Retention ponds: A facility designed to temporarily
store feedlot runoff and waste water
b. Diversion terraces: An earthen embankment used to divert
surface water away from the feedlot surface
c. Settling basins: A shallow pit between the feedlot
surface and the retention pond to allow heavier solids
to settle out of the runoff prior to reaching the
retention pond
130
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Exhibit VIII-12 (continued)
312. LIQUID WASTE CONTROL V
a. Lagoon: An excavated pond for biological treatment of
runoff, waste water and manure
b. Oxidation ditch: An aerated open channel which receives
animal wastes which are reduced by aerobic bacteria-nearly
odorless operation which uses a relatively high quantitiy
of energy and water
313. ODOR CONTROL
a. Feedlot animals: Odors are emitted from the fecal matter
deposited on the feedlot surface - effective controls
have not been established
b. Waste management: Improper operation of retention ponds
allows odor causing anaerobic bacteria to grow
314. DUST AND PEST CONTROL
a. Feedlot: Flies are a common problem around many feedlots
b. Feed preparation: Rodents and dust generally occur around
feedlots with feed processing equipment
315, SOLIDS DISPOSAL t!
ly: Da
dairy feedlots )
a. Daily: Daily disposal of solid wastes (a common practice
for dai
b. Temporary storage: Temporary storage of wastes ( a new
trend among dairy producers to reduce spreading of wastes
on frozen ground )
c. On site or farm: On site or on farm disposal of solid
wastes is traditional practice of farmer-feeder operations
d. Off site or off farm: Off site or off farm disposal of
solTd wastes (increasing as large feedlots become land
intensive )
316. INCREASING PESTICIDE USE - pesticides has been used for control of
lice, mites, flies, grubs, ticks, screw worms, and mange.
Trend changes were made by the evaluation workshop as noted in
Subsection C-2: Trends and Environmental Implications.
131
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Exhibit VIII-13. Overall trends in feedlot concentrations
Livestock/Year
Total
Estimated No. of Feedlots
1973
953,065
1977
<844,500
1983
Beef
Swine
Sheep
Dairy
Turkey
Duck
185,000
425,000
10,000
329,000
4,000
65
142,500
370,000
(-)
N.A.
3,000
(-)
92,500
287,000
(-)
148,200
2,500
(-)
<540,300
Livestock
Units
Estimated Production
1973
1977
1983
Beef
Swine
Sheep
Dairy
Turkey
Duck
mil .
mi
'mi
bi
mi
mi
1.
1.
1.
1.
1.
head
head
head
Ibs.
birds
birds
31
82
2
115
132
10
.6
.0
.8
.0
.0
.99
38
96
N.
N.
150.
t
A
A
0
rel ati
3
2
•
.
vely
41
106
N.
109
163
constant
.6
.4
A.
.0
.0
Alternative bedding material (304)
odor associated with fecal matter.
however, increases the quantity of
lot.
can reduce the moisture content and
Bedding added to the feedlot surface,
solids to be disposed of from the feed-
Alternative ration composition (305) allows feedlot producers to adjust to
economic conditions. Increased roughage use will tend to increase the
length of the feeding period and the quantity of feedlot wastes. High
grain or concentrate rations tend to increase the demands on cropland
production.
(b) Agricultural Engineering Trends. Agricultural engineers have dealt
with many aspects of the feedlot industry. Facility designs were solely
identified as having important environmental implications. Other contri-
butions by these engineers were included in other trends but were not
specifically identified as engineering contributions.
132
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Alternative facility designs (306) allow for the reduction in feedlot
runoff as exposed surface areas are reduced by various housing types.
Research has also indicated that total confinement systems lower death
losses (10-20%) and increase feed efficiency about 10 percent.
(c) Veterinary Science. Several contributions to the livestock industry
can be attributed to the improved health of livestock.
Veterinary services (307) tend to reduce the incidence of livestock death
and disease. Productivity is generally increased. No correlation with
human health hazards due to chemical treatments has been found.
(d) Economic Trends. The financial incentive to produce feedlot live-
stock has resulted in gains to the owners as well as society. These bene-
fits, however, have been partially offset by the increased incidence of
environmental degradation.
Increased size of feedlots (308) is expected. The environmental implica-
tion is uncertain since the size factor and the geographic location are
both important variables. Generally, increasing the concentration of any
environmentally sensitive factor will put additional demands on the
assimilative capacity of the environment.
Increased geographic concentration of feedlots (309) will increase the
quantity of feedlot wastes which must be assimilated into the local
environment.
Increased specialization, mechanization and multiple man units (310) will
add additional pressure on the environment. Odor, dust and noise pollu-
tion will probably be affected most drastically.
(e) Waste Management Trends. These trends have basically reduced the
potential of environmental degradation. Further efforts are needed to
encourage the proper operation of facilities and the continued adoption
of waste management technology.
Feedlot runoff control (311) affects the quantity of wastes which are
carried by surface water. Feedlot runoff is generally high in B.O.D.
and organic matter. Increased control will require additional cropland
disposal sites which mav affect cropland production.
Liquid waste controls (312) are designed to decompose animal wastes.
These practices reduce the quantity of solids which must be disposed
on to cropland.
Odor controls (313) are essential non-existent for feedlots. As feedlots
increase in size and population centers expand, continued conflicts are
expected. Proper waste management can affect the odors resulting from
feedlot runoff systems.
133
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Dust and pest controls (314) affect the air and health environment of
surrounding population centers.
Solids disposal (315) affect the quality of cropland runoff. Daily
spreading encourages solid disposals on wet and frozen ground; such
activity permits potential surface water runoff degradation. Temporary
storage can reduce surface water runoff but it can also reduce the en-
vironmental aesthetics and may increase odor potential.
Increasing pesticide use (316) has occurred with new chemical develop-
ments. Approximately 5-6 percent of the pesticide expenditures in 1964
were applied to livestock and poultry. The application of insecticides
to and around livestock is regulated by the USDA and the Federal Food
and Drug Administration to limit the health hazard of contaminated
meat and milk.
134
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SECTION IX
ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVICULTURAL TRENDS:
PANEL 4 - RANGE AND PASTURE MANAGEMENT
The Range and Pasture Management Panel evaluated and ranked the maor en-
vironmentally related trends in this subsector of agriculture as summarized
in Exhibit IX-1, and as described briefly in Exhibit IX-2. Also, the panel's
ratings of each subtrends extensiveness of use and intensiveness of environ-
mental effects, which were developed as a means for establishing the overall
environmental ratings, are as shown in Exhibit IX-3.
The trends assessed by Panel 4 were those associated with livestock manage-
ment practices on the nation's 1,202 million acres of rangeland (ranges in
native or natural grasses, plus forested ranges) and the 101 million acres
of land in pastures.
The Range and Pasture Management Panel was comprised of four members and was
chaired by Glen Flucher. The panelists represented a balance both in special-
ties and geographical areas of interest.
Name
Glen D. Fulcher
John Launchbaugh
J. M. Scholl
John Studeman
Representing
Bureau of Land Mgt.
Kansas State Univ.
University of Wis.
Agriculture Research
Service
Specialty
Range Management
Range Management
Forage Crops
Pastures, Animal
Science
Geographical
Area
Western
Great Plains
Northeast
Southeast
A. Major Trend Rankings and Practice Assessments
The trends which Panel 4 considered adequate as a basis for its assessment
were those contained in the Contractor's preliminary report. A number of
modifications were made by the panel: these include the addition of several
subtrends and a combination of a number of trends into single trends. As
previously discussed in Section IV, "Workshop Procedures", the procedure used
by the panel in assessing trends involved: an analysis of the extensiveness
135
-------
(E) and intensiveness (I) of each of the subtrends; a determination of the
overall significance rating (R) of these subtrends (R = EXI); a determination
of a composite rating when all trends were considered; and finally, a ranking
of the trends based on these adjusted ratings (AR). In the initial
assessment by the panel, the individual subtrends were analyzed separ-
ately in pasture and range management because of the significant dif-
ferences between the two; however, in the final ranking, the subtrends
were combined, and a single rating was determined for each trend.
Exhibit IX-1 shows the ranking of the trends as determined by the
panel.
B. Environmental Implications of Major Trends and Practices
Each of the major range and pasture management trends, as determined by
Panel 4, are summarized below. Background descriptions and definitions
of these trends, which served as the basis for the workshop's evalua-
tions, are included for reference in Part C: "Background Summary,"
as needed.
Grazing Practices (406). Panel 4 determined grazing practices to be
the most significant trend, environmentally, both because of the large
Exhibit IX-1
Ranking of environmentally-related trends, 1976-2010:
Range and Pasture Management
Trend
Rank number!/ Trends/
1
2
3
4
5
6
7
8
9
10
11
12
I/ The
1/Thp
406
405
401
416
417
409
408
403
412
414
410
413
trend
nanpl
Grazing practices
Stocking rates
Range and pasture renovation
Using increased resources
Range and pasture improvements
Increasing nutrition from vegetation
Genetic improvements
Inter-seeding improved or preferred
forage varieties
Insect and disease control
Poisonous plant control
Increasing use of irrigation
Small animal control
number reflects those numbers used in the Phase
rankorl nnlv trpnrlQ 1 thrnimh 7 TvonHc P_l 9 UIQV
Adjusted
rating
8
7
6
5
5
4
4
2
2
2
1
1
I-Interim Report
'Q vanl/oH
by DPRA based on the extensiveness and intensiveness ratings made
by the panel.
136
-------
Exhibit IX-2. Description of major environmentally-related trends, 1976-2010; Range and Pasture Manaqement
Panel
Rank
Trend Number and Title
Adjusted Rating
for 20:0
Comments and Modifications
CO
(406) Grazing Practices
(405) Stocking Rates
(401) Range and Pasture Renovation
(416) Using Increased Resources
(417) Range and Pasture Improvements
(409) Increasing Nutrition from
Vegetation
(408) Genetic Improvements
Grazing practices include continuous grazing systems and
specialized systems, which allow for rotations during certain
seasons. A trend toward specialized systems will generally
improve soil and vegetation more rapidly than continuous
grazing.
Proper numbers of animals are allowed to graze for the type
of vegetation and management system used. Proper rates will
enhance forage quality and productivity and reduce soil
erosion.
Renovation practices include mechanical and chemical methods
and prescribed burning. Environmental quality will be in-
proved by the establishment of grass cover and stabilization
of soil.
Range and pasture will use increased amounts of fertilizers
and pesticides, and will develop new range and pasture.
Quality, quantity, and productivity of range and pasture
will be affected beneficially by increased resource use.
The t-end toward water improvement, with the construction of
ponds, catchment basins, and drainage structures, and such
structural developments as fire barriers and fencing, will
aid in grazing management and improve forage quality.
Nutritional levels of vegetation will result from the use
of chemical additives and forage supplements. Quality and
digestibility of forage will improve from use of this trend.
Forage quality will be Improved by the genetic developments
of .'orage with Increased stress tolerance, digestibility,
and production.
-------
Exhibit IX-3. Environmental ratings of top ten trends and associated practices: Range and Pasture Management
CO
00
Rank
1
2
3
4
5
6
7
8
9
10
Trend
Number
(406)
(405)
(401)
(416)
(417)
(409)
(«08)
(403)
(412)
(414)
Extensiveness
Trend and Subtrends
Grazing , ractices
a. Continuous
b. Specialized grazing systems (rotations)
c. Complementary forage seedings
Stocking Rates (controlled grazing)
Range and Pasture Renovation
a. Mechanical
b. Chemical
c. Prescribed burning
Using Increased Resources
T. Using chemicals, pesticides, & fertilizers
b. Developing new range & pasture lands
Range and Pasture Improvements
a. Ponds & catchment basins
b. • Drainage
c. Wells, pipe lines & troughs
d. Range fire barriers
e. Cross & containment fencing
f. Sediment & erosion co.-.trol structures
g. Hater and salt dispersal
Increasing Nutrition from Vegetation
a. Increasing rumen efficiency
b. Increasing retention of forage quality
c. Increasing vitamin & protein supplements
d. Improved nutrient balance
Genetic Development
a. Increasing forage quality & quantity
b. Increasing stress tolerance
Inter-Seeding Improved or Preferred Forage
Varieties
a . Legumes
b. Preferred grasses
Insect and Disease Control
Poisonous (Noxious) Plant Control
Range
(1976)
3
1
1.
2
1
2
1
1
1
2
0
1
1
1
1
2
1
1
2
1
1
1
1
1
<1
1
(1585)
3
1
i.
3
1
2
2
1
1
2
0
2
1
2
2
2
3
1
3
2
1
1
1
1
<1
1
(2010)
2
2
3
A
1
3
2
1
2
3
0
3
2
3
2
3
4
2
3
3
2
2
1
1
<1
1
Pasture
(1976)
2
2
1
2
1
1
0
2
1
1
1
1
0
2
1
1
1
1
1
2
2
1
1
1
2
2
(1981)
2
3
2
3
3
2
0
3
1
2
1
1
0
3
1
2
3
2
2
3
2
2
2
2
2
2
(2010)
2
3
3
4
3
2
0
4
2
2
1
1
0
3
2
3
3
3
2
4
3
3
3
2
3
2
Intensiveness
Range
-2
+2
+2
+3
+2
+1
+2
+1
+2
+2
0
+1
-1
+1
+1
+1
+1
+1
+1
+1
+1
+1
+1
+1
+1
+1
Pasture
+1
+2
+2
+3
+2
+2
N.A.
+2
+2
+1
+1
+1
N.A.
+1
+1
+1
+1
+1
+1
+1
+1
+1
. «
+1
+1
+1
+1
-------
land area involved in pasture and range and because of the environmental
implications of the various types of practices. There was considerable
controversy within the panel concerning the actual trends in practices
that could be expected between now and 2010 and in the environmental
implications of continuous grazing. One point of view held was that
continuous grazing was extremely detrimental to the environment and,
because of this, other types of systems will necessarily have to be
implemented. The opposite point of view was that continuous and properly
controlled grazing was beneficial to the quality of forage and would be
the only system economically feasible in the future. Regardless of the
specific trends and effects (beneficial vs. adverse) under the two points
of view, the panel agreed that trends in grazing practices constitute the
major concern in range and pasture management.
The basic subtrends in grazing practices involve continuous and specialized
systems. Complimentary seeding practices can be incorporated into either
of the two systems. According to the panel, continuous grazing is rela-
tively extensive on ranges, while rotation grazing is minor. By 2010, the
extensiveness of the two will be at somewhat the same levels with continuous
grazing declining and specialized grazing increasing. In pasture opera-
tions, the extensiveness of continuous grazing is expected to remain
essentially the same through 2010; however, with new pasture development,
the specialized systems are expected to increase to a moderate level by
that year. The extensiveness of complimentary seeding is expected to
increase significantly on both range and pasture. As discussed above,
conflicting points of view were expressed in the panel in connection with
the environmental impact of continuous range grazing. Most of the
panelists gave an intensiveness rating of minus 2 to this practice to
reflect the potentially adverse effects of continuous grazing. The
ratings of other subtrends in range and pasture reflected generally
beneficial effects.
Stocking Rates (405). This trend, directed towards controlled (or
proper) stocking rates, was ranked second. The panel's discussion
of this trend centered on what the trend toward proper rates actually
meant and where or how the trend should be classified. In most of the
regions, a trend towards controlled rates suggests that the change
will be from overgrazing to proper grazing. However, in the South-
east, the trend reflects a change from undergrazing to proper grazing,
for there, the problem is one of undergrazing which results in the
growth of less desirable grasses and forbs. Two of the panelists
felt that the stocking rate was a component of the grazing system and,
consequently, should be combined with grazing systems. However, the
trend was kept separate and was given a rating in environmental signi-
ficance close to that of grazing practices.
The trend toward controlled (or proper) stocking rates was considered
essentially the same in both range and pasture management. Currently,
the extensiveness of proper grazing is considered relatively minor;
however, by 2010 it is expected to increase significantly to an im-
portant level. This trend is expected to have a significantly bene-
139
-------
ficial effect on the environment as reflected in the intensiveness
rating given by the panel.
Range and Pasture Renovation (401). This trend, ranked third, was con-
sidered to include nonstructural improvements such as revegetation and
brush control and seedbed preparation in pastures. The panel concluded
that renovation was a more significant factor in pasture operations
than it was in range management.
As indicated in Exhibit IX-3, the panel expects the trend in mechanical
renovation to increase significantly by 2010 in pasture operation while
it is expected to remain at a minor level in range operations. On the
other hand, the panel rated the extensiveness of chemical renovation
as relatively more important in range management than in pasture oper-
ations. Chemical application on both range and pasture is expected to
increase slightly by 2010. The environmental effects associated with
these types of renovation were judged by the panel to have overall bene-
ficial effect even though, in most cases, short-term detrimental effects
may occur, primarily from soil compaction and disturbance. Prescribed
range burning is occurring now only at minor levels, but it is expected
to increase somewhat by 2010. Again the effects are beneficial in the
long run. Prescribed burning is not expected for pasture renovation.
Using Increased Resources (416). The panel ranked this trend fourth,
although its adjusted rating of vie was the same as fifth ranked,
Range and Pasture Improvements (417). It is a composite of Trends 411
and 415 as described in Part C, below. Increased use of fertilizer,
pesticides, and chemicals on land and as well as the development of
new pasture and range lands are covered by this trend. The panel con-
cluded that the development of new pastures and ranges is expected to
occur primarily in the Southeast with foest land here being converted
to range and pasture. Use of these increased resources was adjudged
by the panel to have overall beneficial effects upon the environment
even in light of potentially adverse short-term effects. Chemicals
and pesticides are currently being used only to a minor degree on
ranges; no significant changes in this use are anticipated for 2010.
This use is considerably greater on pasture and is expected to in-
crease to even higher levels by 2010. In developing new range and
pasture, only a slight increase is expected by 2010; the most exten-
sive development is anticipated to occur in the Southwest.
Range and Pasture Improvements (417). This trend, ranked five, is a
consolidation of trends 402, 404 and 407 contained in Part C, below,
including an increasing use of structural improvements in water de-
velopment, fencing, erosion control, and fire barriers.
The extensiveness of the use of these improvements was considered cur-
rently minor for both range and pasture but are expected to increase
slightly by 2010. All of these trends in the developments were given
beneficial ratings in intensiveness except in the case of fire barriers.
The panel felt that the use of fire barriers would impede the use of con-
trolled fires on ranges and, consequently, it would result in some ad-
140
-------
verse effects. As shown in Exhibit IX-3, the remaining subtrends in
range and pasture management were expected to have beneficial effects;
however, as reflected in the intensiveness ratings, these effects were
expected to be relatively minor.
Other trends. The panel ranked two additional trends. Increasing Nutri-
tion from Vegetation (409) and Genetic Improvements (408) at an adjusted
rating of four. The remaining trends contained in the Phase I-Interim
Report were considered by the panel to be relatively minor and were not
ranked. They are listed in Exhibit IX-3 with extensiveness and inten-
siveness ratings as discussed below.
The rankingsoutlined above were arrived at by the panel based on its
evaluation of the extensiveness and intensiveness ratings. Ratings
for the subtrends are shown in Exhibit IX-3 for both range and pasture
management.
C. Background Summary
The following descriptions and definitions of trends and practices
(subtrends) related to range and pasture management were provided to
the workshop participants as background for the workshop evaluation.
In some cases, the panel members chose to re-group selected subtrends
or add/delete subtrends as noted. As such, this summary is quasi-
independent of the workshop results in Parts A and B, above. However,
it provides appropriate background base data, definitions and descrip-
tions of the trends and practices assessed in this portion of the total
study.
1. Overview and Base Data
Ranges, which include both rangeland (lands in native and natural grass)
and forest land, comprised 1202 million acres in 1970 in the conterminous
48 states (USDA, 72). The total acreage of rangeland and the percent of
it that is grazed for each of the ecogroups is listed below.
U.S. Ranqeland in 1970
Ranges Grazed
Ecogroup Total Ranges Acres Percent
(million acresl
Western Range 418.6 360.8 86
Western Forest 160.6 97.2 61
Great Plains 228.9 217.1 95
Eastern Forest 393.4 159.8 41_
ALL RANGES 1,201.5 834.9 70
1.41
-------
Alaska's ranges comprise over 300 million acres; however, largely
federally owned, they were grazed very little. Hawaii has less than
3 million acres and most is under private ownership.
Over 50 percent of the ranges in the Western area are under federal
ownership. On the other hand, in the Great Plains, just over 10 percent
is federally owned and, in the Eastern Forest, less than 10 percent.
The level and types of range management vary significantly among the
ecogroups. The most extensive use of range occurs in the Great Plains
with over 90 percent of the range being grazed. The least extensive
use of range occurs in the Eastern Forest with only about 40 percent
of the rangeland being used for grazing purposes.
The 1970 total acreage in improved pastures is listed below (USDA, 72).
Pastures differ from ranges in two respects: (1) pasture forages are
generally non-native and (2) pastures generally receive annual improvment
such as fertilization.
Improved Pastures by Geographic Region
Geographic Region Pastures Percent
(million acres)
Western 8.9 9
Plains 24.0 24
Northeast 39.9 39
Southeast 28.3 28
Total 101.1 100
Source: The Nation's Range Resources (USDA, 72).
The potential sources of pollution from ranges and pastures include
sediment, pesticides, fertilizer, and animal and plant wastes. These
pollutants can be transported to surface waters by direct runoff, sedi-
ment movement, or percolation.
Sediment is not only the most significant pollutant in terms of volume,
but it is also the chief carrier of plant nutrients, pesticides, organic
and inorganic matter, pathogens, and other water pollutants. While sedi-
ment from ranges and pastures contribute to water pollution, soil erosion
(movement of the sediment from the land) represents the greatest environ-
mental damage to the land itself. Soil erosion presents more significant
problems on ranges than it does on pastures, because of the improvements
that pastures receive. The range acre rates for hydralogic output by eco-
group are listed below.
142
-------
Ecogroup Water Yield Quality Water Storm Runoff- Sediment
Acre Feed Acre Feed Per Inches Per Tons Per
Acre Per Year Acre Per
Year
Western Range 0.24 0.23 0.32 2.74
Western Forest 1.10 1.05 0.44 0.52
Great Plains 0.80 0.03 0.72 1.12
Eastern Forest 1.24 1.11 1.37 0.43
Weighted Average 0.65 0.59 0.76 1.38
]_/ Runoff expected from a 2-year 2-day storm.
Source: The Nation's Range Resources (USDA, 72).
The annual loss of sediment from ranges averages 1.38 tons per acre. The
loss in the Western Range is over twice as much as for any of the other groups
even though the water yield and storm runoff is significantly less. The
Eastern Forest which has the greatest water yield and storm runoff has the
least sediment loss. In recent estimates made by the Environmental Protec-
tion Agency, the total annual sediment loss from both ranges and pastures
is about 1.2 billion tons. Cropland which comprises total acreage of less
than a fourth of that of ranges and pastures accounts for 1.8 billion tons.
Two types of nutrients are recognized as presenting possible and differing
pollution problems on ranges and pastures: nitrogen and phosphorus. Sources
for these nutrients are fertilizer and animal wastes. Nitrogen, more sol-
uble in water, can pollute both surface and ground water through direct
runoff or percolation; phosphorus relatively insoluble attaches itself to
sediment and moves with it to surface water. While fertilizers and animal
wastes are possible pollutants from ranges and pastures, their actual con-
tribution to the nutrient loading of waterways is relatively minor. Recent
estimates by the Environmental Protection Agency show that nitrogen loading
of water from ranges and pastures, is several tons per day less than cropland
loading. On a weighted average basis, this would indicate that similar
loading from cropland is close to six times as great as that from ranges and
pastures. By far the greatest amount of the nutrients entering the water
are from background concentrations, i.e., natural sources—soil and organic
matter). The actual overall loadings resulting from range and pasture
management is not known; however, it is assumed to be relatively insignifi-
cant. Many studies have concluded that nutrient loading is most reflective
of rainfall amounts than of fertilization ratios.
Most pesticides applied to pastures and ranges are herbicides used for the
control of undesirable vegetation. In 1971, a total of 8.3 million pounds
of these pesticides was applied to pastures and rangelands (USDA, 72), a
total less than 4 percent of that applied to croplands. A number of research
studies have concluded that less than 5 percent of the pesticides enters the
waterways through runoff.
143
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2. Trends and Environmental Implications ^/
Management of ranges and pastures involve the utilization of practices
which differ considerably among ecogroups. Although the entire management
system must be viewed within these ecogroups in order to assess the total
impact on the environment, each of the practices can be examined in
determining its specific implications.
Trends. The general relationship of these practices within the
management systems are illustrated in Exhibit IX-4. Included in the
system are the management practices (resource management) resource
inputs, technological developments, and system outputs to include
the major residuals generated. This system provides the framework
in which the trends in range and pasture management have been iden-
tified. Those trends to be discussed and analyzed are listed in Ex-
hibit IX-5 and then described in Exhibit IX-6. The trends have been
grouped under the following major headings: (1) range and pasture
developments, (2) grazing management trends, (3) plant improvements,
(4) nutrition improvements, (5) irrigation technology, and (6) ferti-
lizer developments and range pollution trends.
Environmental Implications. In the analysis of trends, the matrix
contained in Exhibit IX-7 was developed so that potential inter-
actions between the specific practices and pollutants generated
could be examined. These interactions represent changes that would
occur in the amounts of pollutants produced on a representative range
or pasture managed under practices assumed to be utilized in 1976.
The interactions were denoted with pluses (+) and minuses (-), a
decreasing effect or beneficial impact was indicated with a +,
an increasing effect on pollutants generated was indicated with a
-. Based on a review of these interactions, general conclusions
were drawn on the trends and environmental implications.
(a) Range and pasture developments. Trends in range and pasture de-
velopments included range renovation, water improvements, inter-
seeding improved or preferred grass varieties and structural de-
velopments.
Brush control used in renovation (401) (primarily range) can be ac-
complished by a number of means to include: mechanical, chemicals,
or burning. Each of these measures has both short term and long
term effects on the environment. In the short term, mechanical
- Though not of substantive concern affecting trend rankings and practice
assessments arrived at in.this study, major trend categories discussed in
these base data were in some cases regrouped to facilitate workshop panel
discussions. These changes are as follows:
Base data categories became Revised categories
402, 404, 407 417
411 and 415 416
144
-------
Exhibit IX-4. Range and pasture systems
Ol
SCIENCE I
TECHNOLOGY
RES08RCES
IflPUT
RESOURCE
OEVELOP-
ME!,TS IK
RANGE
MANAGEMENT
1
f
RAIIOC
MANAGEMENT
'
ANIKAL
BREEDING
1
r
XIN3 I
CLASS OF
LIVESTOCK
<
r
GRAZING
MANAGEMENT
PRACTICES
r i
PLANT
IMPROVEMENT
(forages)
^
SEEDS
'
'
SEED3ED
PREPARATION
r 1
J
RESEEOING
1
RENOVATION
p ^
FERTILIZER
DEVELOPMENT
<
'
FERTILIZER
i
FEED
SCIENCE
i
'
FEEDS, FEED
SUPPLEMENTS
I SALTS
' •<
FERTILI-
ZATION
' 1
1 •
WATER
DEVELOPMENT
1
IRRIGATION
TECHNOLOGT
r l
WATER
• 1
FEEDING
' ^
PEST1CIJE
DEVCLOPME.T
r '
WATER
' <
WATERING
' i
r
IRRIGATION
t \
T
PESTICIDES
t CHEMICAiS
i
PEST 1
PLANT
COMML
F 1
YIELD
OUTPUT
OUTPUT
V
SEDIMENT
I
NUTRIENTS
V
PESTICIDES
CHEMICALS 1
WASTE
WATER
^
f
ain-
DEGRADABLE
ORGANICS
v
ANIMAL
WASTES
1
^r V» .
«^rl!i t I PRODUCTION !
MINERALS j |l
f
PATHOGENS
OTHER PRACTICES : Htrding. Hunting. Ftncing. Prtditor control
-------
Exhibit IX-5. Environmentally-related trends: Range and Pasture
RANGE AND PASTURE DEVELOPMENTS
401. RANGE RENOVATION
a. Mechanical
b. Chemical
c. Prescribed burning
402. WATER IMPROVEMENT: RANGE AND PASTURE -/
a. Ponds and catchment basins
b. Drainage
403. INTER-SEEDING IMPROVED OR PREFERRED GRASS VARIETIES: RANGE
AND PASTURE
404. STRUCTURAL DEVELOPMENTS: RANGE AND PASTURE I/
a. Range fire barriers
b. Cross and containment fencing
GRAZING MANAGEMENT TRENDS
405. STOCKING RATES: RANGE AND PASTURE
a. Proper use - range
b. Proper use - pasture
406. GRAZING PRACTICES: RANGE AND PASTURE
a. Continuous
b. Deferred Rotation
c. Rest Rotation
407. DECREASING LIVESTOCK CONCENTRATION: RANGE AND PASTURE
a. Water and salt dispersal
b. Cross fencing
PLANT IMPROVEMENTS
408. GENETIC DEVELOPMENT: RANGE AND PASTURE I/
a. Increasing forage quality and quantity
b. Increasing stress tolerance
NUTRITIONAL IMPROVEMENTS
409. INCREASING NUTRITION FROM VEGETATION: RANGE AND PASTURE
a. Increasing rumen efficiency - monensin
b. Increasing retention of forage quality-chemical treatment
c. Increasing vitamin and protein supplements
- Included in Workshop Panel ratings as Trend 117.
146
-------
Exhibit IX-5 (continued)
IRRIGATION IbUiiNULUGY
410. INCREASING USE OF IRRIGATION
a. Range irrigation
b. Pasture irrigation
FERTILIZER DEVELOPMENTS
411. INCREASING FERTILIZER USE */
a. Commercial application to range
b. Commercial application to pasture
c. Biological nitrogen fixation
RANGE AND PASTURE PROTECTION TRENDS
412. INSECT AND DISEASE CONTROL
a. Range (surveillance, chemicals)
b. Pasture (surveillance, chemicals)
413. SMALL ANIMAL CONTROL
a. Range control (surveillance, chemicals)
b. Pasture control (surveillance, chemicals)
414. POISONOUS PLANT CONTROL
a. Range control (herbicides, controlled grazing)
b. Pasture control (herbicides, controlled grazing)
RESOURCE USE TRENDS
415. USING INCREASED RESOURCES £/
a. Using chemicals, pesticides and fertilizer on range land
b. Using chemicals, pesticides and fertilizers on pasture land
c. Developing new range and pasture lands
2/
— Included in Workshop Panel ratings as Trend 116.
147
-------
Exhibit IX-6. Description of environmentally-related trends and
developments in range and pasture
RANGE AND PASTURE DEVELOPMENTS
401. RANGE RENOVATION
a. Mechanical: cutting and/or uprooting range
shrubs by tractors, chains, blades, etc.
b. Chemicals: herbicide application by aerial or
ground equipment to eleminate shrubs and un-
desirable plants
c. Prescribed burning: predetermined range areas
are intentionally burned to control undesirable
shrubs
402. WATER IMPROVEMENTS*/
a. Ponds and catchment basins: water impoundment made by
constructing a dam or excavating a pit
b. Drainage: removing excess surface or ground water
403. INTER-SEEDING IMPROVED OR PREFERRED GRASS VARIETIES ^planting
seeds among existing grass varieties
404. STRUCTURAL DEVELOPMENTS
a. Fire barriers: creating a barrier of bare or scoured
earth between rangeland and fire hazards such as high-
way, railroad
b. Fencing: containment and cross fencing
GRAZING MANAGEMENT TRENDS
405. STOCKING RATES: RANGE AND PASTURE
a. Proper use range: the proper number of
animals are allowed to graze for the type
of vegetation and management system used.
b. Proper use pasture: the proper number of
animals are allowed to graze for the type
and condition of vegetation and management
system used.
406. GRAZING PRACTICES: Range and Pasture
a. Continuous grazing: vegetation is entirely grazed
by stock
b. Deferred Rotation: alternate use of grazing areas
to develop production of desired species of grass
c. Rest rotation: grazing occurs only during certain
seasons and allows a given area to grow without
livestock interference
148
-------
Exhibit IX-6 (continued)
407. DECREASING LIVESTOCK CONCENTRATION -f
a. Pond and salt dispersal: water and salt are strategically
located to encourage less intensive grazing at specific
sites
b. Cross fencing: used to restrict movement of livestock
towards habitually preferred areas
408. GENETIC DEVELOPMENTS
a. Increasing forage quality and quantity: genetically
developing forage to enhance digestibility, palatability
and production
b. Increasing stress tolerance: genetically developing
grass to produce under saline, drought or excessive
moisture conditions
NUTRITIONAL IMPROVEMENTS
409. INCREASING FORAGE NUTRITION
a. Increasing rumen efficiency: chemical additives de-
signed to increase ruminant's capability to absorb
forage nutrients (monensin)
b. Increasing retention of forage quality: chemical
treatment for maintaining forage quality
c. Increasing vitamin and protein supplements: adding
vitamins and proteins to supplement the nutritive
quality of forage
IRRIGATION TECHNOLOGY
410. INCREASING USE OF IRRIGATION: on ranges and pasture to increase
productivity (sprinklers and well developments are increasing
in usage)
FERTILIZER DEVELOPMENTS
411. INCREASING FERTILIZER USE*/
a. Range applications: relatively limited quantities are
applied since a large share of rangeland is in arid regions
b. Pasture applications: wide range in fertilizer quantity
and composition
RANGE AND PASTURE PROTECTION TRENDS
412. INSECT AND DISEASE CONTROL
a. Ranges: scouting by visual surveillance, use
of pesticides
b. Pastures: scouting by visual surveillance using
pesticides, nematacides, fungicides, bacteriocides
149
-------
Exhibit IX-6 (continued)
413. SMALL ANIMAL CONTROL
a. Ranges
b. Pastures
414. POISONOUS PLANT CONTROL
a. Range: surveillance controlled grazing, herbicides,
burning
b. Pasture: surveillance controlled grazing, herbicides,
burning
RESOURCE USE TRENDS
415. USING INCREASED RESOURCES */
a. Chemicals and pesticides on rangeland
b. Chemicals, pesticides, and fertilizers on pasturelands
c. Developing new range and pasturelands
*/
— See subsection C-2: Trends and Environmental Implications, for changes
in trend groupngs by the evaluation workshop..
150
-------
Exhibit U-7. Environmentally-related trends: Ranges and Pastures
Potential Contribution to
Surface Hater
TRENDS
RANGE AND PASTURE DEVELOPMENTS
401.
402.
403.
404.
GRAZING
405.
<06.
RAHGE RENOVATION
a. Mechanical
b. Chemical
c. Prescribed burning
WATER IMPROVEMENTS: RANGE & PASTURE
a. Por.ds & catchment basins
b. Drainage
1NTERSEED1NG: RANGE & PASTURE
STRUCTURAL DEVELOPMENTS: RANGE AND
PASTURE
a. Range fire barriers
b. Cross ant! containment fencing
MANAGEMENT TRENDS
STOCKING RATES
a. Controlled range grazing
b. Controlled pasture grazing
GRAZING PRACTICES: RANGES & PASTURES
a. Continuous
b. Deferred rotation
c. Rest rotation
Ssdi- Nitro-
nent gen
0
0
0 0
0
+ 0
+- 0
+ 0
+ 0
0 0
0 0
0 0
-v 0
+ 0
+ 0
+ 0
0 0
+ 0
+ 0
Phos-
phorus.
-
.
0
-
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pesti-
cides
-
0
-
0
0
0
0
0
c
0
0
0
0
0
0
0
0
0
Inorganic
salt and
minerals
0
0
0
0
+
0
+
0
0
0
0
0
0
0
0
0
0
0
Biode-
gradable
ors.vi1cs
-
_
•_
-
0
0
0
-
0
0
0
_
-
-
_
0
_
-
?ol tjtior.-
Ground Hater
Nitrates
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3
Pesti-
cides
0
0
0
0
0
0
0
0
0
0
0
0
c
0
0
0
0
0
Inorgamc
salt and
minerals
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3!Po~-~
Vb'Vhta
rts
Air
Gases
C
c
c
0
0
0
0
0
0
0
0
c
0
c
c
0
0
0
Par-
ticu-
lars
-
-
0
-
4-
+.
*
•f
0
0
0
+
4-
+
+
0
+
4-
S011
erosion
-
_
0
-
+
+.
+
+
0
0
0
+.
4-
+
+
0
•f
4-
Sa-
linity
Q
0
0
0
0
0
0
0
0
c
0
0
0
0
0
0
0
0
L*ra
Heavy
raetals
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Pesti-
cii-e
residues
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
orcsnics
-
_
_
-
0
0
-
-
0
0
0
_
-
-
_
0
_
-
-------
Exhibit IX-7 (continued)
TRENDS
Potential Contributicn re Pal.uticr—v~:or Pollutants
Surface Water
GrounJ Hater
Inorganic Bio£a- Inorganic
52
-------
measures such as root plowing, chaining, crushing, and pushing
contribute to water pollution by increasing (in many cases) soil
erosion. The application of herbicides may present problems under
some conditions in pesticide runoff. However, in the long run, these
practices enhance the environment by establishing grass cover and
stabilizing the soil.
Water improvements (402) include the construction of ponds and catch-
ment basins and drainage. Ponds and catchment basins, used in
watering livestock, affect the environment both directly and in-
directly. As a method of water conservation, they decrease the
erosion potential of the soil. Their major impact on the environ-
ment is indirect and involves livestock distribution on the ranges
and pastures. Proper location of these developments reduces the
concentration of livestock in small areas decreasing the chances of
bare spots and sedimentation of nearly streams. Drainage, which is
relatively a small trend on ranges, is used to improve the forage and
access. Its environmental implications are an improvement in soil
stability as well as producing a higher quality forage.
Interseeding improved or preferred grass varieties (403) is used both on
pastures and ranges and is used principally for improving the quality of
the forage. However, benefits to the environment accrue from an improved
soil cover which maintains itself over a longer period of time. Inter-
seeding introduces improved species as well as reestablishing indigious
species.
Structural developments (404) include measures designed to aid grazing
management and to protect the forage. Important trends are an increasing
use of fine barriers on ranges and cross and containment fencing on both
ranges and pastures. The benefits to the environment of these develop-
ments are primarily indirect and relate to the protection of the forage
which in turn promotes soil stability.
(b) Grazing management trends^ Grazing management is conducted under two
basic systems: continuous and rotation. Significant practices include
stocking rates and measures in decrease livestock concentration.
Stocking rates (405) have significant environmental implications both
on ranges and pastures. High stocking rates not only affect the con-
dition and productiveness of the forage but also reduces soil stability
causing erosion and compaction of the soil. On the other hand, low
stocking rates generally enhance forage productivity and reduces soil
erosion.
Grazing practice (406), as indicated above, include continuous and
rotation grazing. In turn, rotation contains two variations: deferred
and rest. Rotation grazing is a more intensive system of management
and generally improve soil and vegetation conditions more rapidly than
the continuous system.
153
-------
Decreasing livestock concentration (407) is accomplished by measures such
as pond and salt dispersed and fencing. By controlling livestock dis-
tribution on ranges and pastures, problems in erosion associated with
compaction and bare spots can be reduced.
(c) Plant improvements. Trends in plant improvement are expected to
occur both on range and pasture and involve genetic developments.
Genetic development (408) encompasses a wide variety of scientific
developments that increase the forage quality and quantity and stress
tolerances. These innovations contribute to soil stability primarily
by introducing on range and pasture a more effective ground cover.
(d) Nutrition improvements. Increasing nutrition from vegetation (409)
is not only beneficial to livestock production but also increase the
grazing capacity of range and pasture. This reduces the potential
for overgrazing and decreases problems in soil erosion. Specific
trends include increasing rumen efficiency, retention of forage
quality-chemical treatment, and vitamin and protein supplements.
(e) Irrigation technology. There is a trend in the increasing use of
irrigation (410) both on range and pasture. Increasingly areas deficient
in water are receiving applications of water by sprinklers and
This is increasing the forage quality and grazing capacity with beneficial
effects on the environment (primarily soil stability).
(f) Fertilizer developments. Increasing fertilizer use (411) on range
and pasture is expected to have both beneficial and adverse effects.
Increasing rates may present some problems in water pollution with the
possibility of greater runoff. However, a more significant effect relates
to the increase in herbage production and quality which will increase
the grazing capacities. As discussed above, this will lessen the potential
of soil erosion.
(g) Range and pasture protection trends. Range and pasture protection
refers to those practices used to control insects, diseases, and small
animals which reduce the production of forage.
Insect and disease control (412) includes both chemical and biological
treatments; however, the major trends are toward pesticide use. Potential
problems exist both on ranges and pastures from pesticide runoff; in
addition, destruction of insects may affect primary food chains on the
range with adverse effects on wildlife.
Small animal (rodent) control (413) includes both chemical and mechanical
measures and is frequently accomplished in conjunction with seeding on
ranges. The environmental impact of these controls, as in insect control,
primarily relates to damages to wildlife rather than water or land pollu-
tion. The destruction of rodents interrupts a primary food chain on
the ranges.
154
-------
Poisonous plant control (414) can involve a number of control measures
to include mechanical, chemical, and biological means and by prescribed
fire. The control of noxious and poisonous plants pose problems similar
to those associated with insect and rodent control. While the threat of
water pollution is minor, the potential damages to wildlife are more
significant.
(h) Resource use trends (415). The trends discussed above were viewed
in light of impacts which were expected to occur from changes in prac-
tices as utilized on a hypothetical range and pasture. In many cases,
the practices involved changes in the use of resources such as land,
pesticides, and fertilizer. Collectively, these practices may be expected
to have significant effects on resource use and hence on the environment,
although the trends with overriding importance are those of increasing
levels of resource inputs associated with the increasing demand for live-
stock products. The inputs that pose significant environmental implications
are fertilizers, pesticides, and land used in range and pasture development.
By the year 2010, the use of fertilizers and pesticides is projected to
increase substantially. These increases, which constitute the basic forces
on the environment, bring into focus the fundamental problems involving
water, air, and land pollution. All of the practices and developments
previously identified must be viewed in this perspective.
155
-------
SECTION X
ENVIRONMENTAL IMPLICATIONS OF AGRICULTURAL AND SILVICULTURAL TRENDS:
PANEL 5 - SILVICULTURE AND HARVEST MANAGEMENT
Panel 5 assessed and ranked the major environmentally related trends in
silviculture and harvest management as summarized in Exhibit X-l. Brief
definitions and descriptions of these trends are presented in Exhibit
X-2; and these trends are discussed further in Part C: "Background Sum-
mary," which was provided to the workshop participants prior to the work-
shop as a basis for the workshop evaluation. Over 490 million acres of
commercial timber owned by the federal government, industry and private
individuals are represented by the Panel's assessment area.
The Silviculture and Harvest Management Panel assessed each trend and its
environmental implications at both the regional and national levels. Ex-
hibit X-3, prepared directly by Panel 5, illustrates, the expected regional
as well as the national environmental implications of selected trends be-
tween 1976 and 20"!0. Also, each subtrend was rated according to its ex-
tensiveness of use and intensiveness of environmental effect for 1976 and
2010 as summarized in Exhibit X-4. These ratings were then used to
establish overall trend ratings by the panel.
The Silviculture and Harvest Management Panel was comprised of five ex-
perts from the government, education and industry. Panel members with
their speciality and geographic area are listed below. Noel Larson
was panel chairman.
Name
Noel Larson
Representing
U.S. Forest Service
Washington, D. C.
George Dissmeyer U.S. Forest Service
Atlanta, Georgia
Warren Harper
Stanley Ursic
David Wooldridge University of Washington
Weyerhaeuser Co.
Tacoma, Washington
U.S. Forest Service
Oxford, Mississippi
Specialty
Hydrology
Hydrology
Hydrology and
Harvest Mgt.
Hydrology
Forest Watershed
Management
Geographic
Area
California
South and
Southeast
Pacific Coast
South
Pacific Coast
156
-------
Exhibit X-l. Ranking of environmentally-related trends,
1976-2010: Silviculture and Harvest Management
Panel
Rank
1
2
3
4
5
6
7
8
9
10
Trend
Number I/
(502)
(505)
(503)
(504)
(510)
(508)
(507)
(509)
(501)
(506)
Trend
Access to timber resource
Site preparation
Log extraction
Utilization
Fire control
Growth enhancement
Stand conversion
Pest control
Cutting system
Stand establishment
Adjusted
Rating
4
4
3
2
2
2
2
2
1
1
I/ The trend number reflects those numbers used in the Phase I—
Interim Report.
A. Major Trend Rankings and Practices Assessments
The "Background Summary" contains the silviculture trends that Panel 5
assessed and ranked. Each panel was free to delete any of these trends,
and new trends, or make other necessary changes to effectively arrive at
trends representing their area. The Silviculture panel did not add or
delete major trends, but did make minor changes at the subtrend level.
The Silviculture Panel felt there were many regional differences within
silviculture trends and their implications. Management of a Douglas Fir
forest in Oregon is completely different from the management of the South's
pine forest, and both are very different from that for the hardwood forests
of the North; consequently, trends and their implications were assessed
on a regional basis by forest types. These regions and forest types are
the West, mixed conifer; the East, hardwood; the East, softwood. Finally
a national assessment was made by adding regional implication assessments.
Exhibit X-3 presents this implication assessment of trends by regions
and nationally for 1976 and 2010. The implications of silviculture trends
were given a 100 rating, nationally, for 1976.
157
-------
Exhibt X-2. Description of major environmentally-related trends, 1976-2010: Silviculture and Harvest Management
Panel
Rank
Trend Number and Title
Adjusted Rating
for 2010
Comments and Modifications
en
CO
10
(502) Access to Timber Resource
(505) Site Preparation
(503) Log Extraction
(504) Utilization
(510) Fire Control
(SOS) Growth Enhancement
(507) Stand Conversion
(509) Pest Control
(501) Cutting System
(506) Stand Establishment
Trends to provide access roads to timber resources will be
for construction of permanent and temporary roads and for
reconstruction of permanent and temporary roads and for
reconstruction and maintenance of existing roads. Emphasis
will be on temporary roads and road maintenance and recon-
struction as harvesting management intensifies.
Fertilizer and chemical treatments, burning prescriptions,
mechanical preparations and log extraction methods will be
used to create more favorable planting sites. Forest re-
generation will be enhanced by these practices.
Harvest management will use olens and specifications for
optimum log extraction systems. Production machinery will
be used in log extractions with trends toward newer, more
efficient machines and application methods.
Loqgir practices will develop to use smaller logs, than cur-
rently being extracted, to use tree species now considered
non-conmercial, and to use waste material left in forest
after extraction.
Improved fire prevention and detection methods, use of fire
to reduce disastrous fire potential, and wildlife suppres-
sion will be used by silviculture in 2010 for fire control.
Forest growth rates and production levels will increase with
thinning practices, elimination of noncommercial tree species,
and with use of fertilization, fire, and chemical application
practices.
Management programs will eliminate undesirable tree species
and plant desirable commercial tree species in their place.
Forest pest control practices will include use of pesticides,
use of biological agents (attractants, repellants, pheromones),
and use of mechanical methods to eliminate infested material.
Trends in forest cutting systems are clear cutting, seedtree
cutting, group cutting, selection cutting, and shelterwood and
diameter cuttings. Each management system will use the cut-
ting method that best meets its needs.
Forest regenerations will be er'-anced, by determining the
best met'iod of regeneration, best species to be planted,
and best type of planting material, method, and spacing for
that species.
-------
Exhibit X-3. Environmental Implications of all silviculture trends, regional and national, 1976-2010 I/
in
10
Panel
Rank
1
2
3
4
5
6
7
8
9
10
Trend
Number
(502)
(505)
(503)
(504)
(510)
(508)
(507)
(509)
(501)
(506)
Western Region-1976 Eastern Regions-1976 1
Trend
Access to Timber Resources
Site Preparation
Log Extraction
Utilization
Fire Control
Growth Enhancement
Stand Conversion
Pest Control
Cutting System
Stand establishment
TOTALS
Mixed Conifer
28
3
4
1
3
1
1
Trace
1
Trace
42+
Hardwood
3
1
4
1
1
1
—
Trace
1
Trace
12+
Softwood
4
26
2
2
2
2
6
Trace »
«_ B
Trace =
44+ =
tetional-
1976
35
30
10
4
6
4
7
1
2
1
100
Western Region-2010 Eastern Regions-2010 Natlonal-
Mixed Conifer Hardwood Softwood 2010
20
4
4
1
3
2
1
Trace
1
Trace
36+
3
3
4
2
1
2
--
Trace
1
Trace
16+
2
18
2
3
2
3
5
Trace •
_• e
Trace »
35+ =
25
25
10
6
6
7
6
1
2
1
89
I/ The environmental implications resulting from all silviculture trends was given a national rating of 100 in 1976. Each trend contributed a certain
percent to this 100 implication value as shown in the National column for 1976. Additionally, there are regional differences for the use and imple-
mentation of each trend, so that the national implication rating for each trend was divided into three regional implication values reflecting the
impact of the trend in that region (i.e. in 1976, Timber Access (502) was resonpslble for 35 percent of all the environmental Implications from
silviculture, with 28 percent resulting from Western region timber access practices, 3 percent from Eastern hardwood region, and 4 percent from the
Eastern softwood region).
These trends were also assessed by regions and natiortaHv for 2010. The national implication value in 2010 was 89 reflecting an 11 percent decrease
In environmental implications from silviculture.
-------
Exhibit X-4. Environmental rating of top ten trends and associated practices: Silviculture and Harvest Management
Rank
1
2
3
4
S
6
7
8
9
10
Trend
Nunber Irene! and Subtrencs
(502)
(505)
(503)
(504)
(510)
(508)
(507)
(509)
(501)
(506)
a.
-------
2010 intensiveness (I) values. The final rating value was derived by
comparing the rating (E X I) for 1976 and the rating (E X I) for 2010.
If the rating improved in 2010 (i.e., current rating was -8, and 2010
rating was -1), the overall rating (R) was positive. The panel considered
this to be a beneficial effect upon the environment. If a trend became
less positive in 2010, the change was judged to be adverse in effect.
This procedure reflects a true change in the rating (R) of each trend.
The Silviculture Panel reflected two additional considerations in
arriving at ratings and ranks for each trend. First, silviculture
practices and management would be more efficient in 2010; thus, the
environmental implications of silviculture would decrease. Second,
aesthetics and certain ecological effects were seen as very complex
issues and the panel did not feel they could assess their intensive-
ness adequately. Thus, these issues were not considered in inten-
siveness assessments. In addition to these considerations, the panel,
also disregarded Alaska's forest systems in their assessments. Although
Alaska's forest inventory and growth capacity are greater than that for
all of the Northern region in the coterminous United States, the ulti-
mate management of this region is still undecided.
The silviculture trends and their ranking are presented below. Their
extensiveness of use and environmental implications are briefly dis-
cussed.
B. Environmental Implications of Major Trends and Practices
Each of the major silviculture and harvest management trends, as deter-
mined by Panel 5, are summarized below. Background descriptions and de-
finitions of these trends, which served as the basis for the workshop's
evaluations, are included for reference in Part C: "Background Summary,"
as needed.
Access to Timber (502). This was ranked the most significant environ-
mentally related silviculture trend. Temporary access roads will con-
tinue to be built as harvest management intensifies. The maintenance
and reconstruction of existing roads will increase by 2010, but con-
struction of permanent roads will decrease to a minor level. Road
building will be concentrated in the Western region. The adverse en-
vironmental effects of creating timber road access will decrease in 2010.
Site Preparation (505). This second ranked trend greatly affects the
Eastern softwood forests, because of the effect of mechanical site prepar-
ation. Extensiveness of associated subtrends show no clear pattern;
some increase slightly; others decrease slightly. Those log extraction
practices which leave the forest site in favorable condition for regen-
eration will largely be Western region activities. Soil moisture control
is a Southern and Lake State practice.
161
-------
Extraction (503). This is ranked third and is concerned with the use of
plans and specification for log extraction and the use and development
of machinery for extraction. This trend and associated subtrends will
increase from the current moderate usage levels to major usage levels
in 2010 and will have a positive effect upon the environment.
Utilization (504). Ranked fourth, utilization has diverse implications
for the future. Two subtrends—minimum size and quality extension of
logs and species usage enlargement—will increase to important levels
in 2010 and will have greater adverse effects upon environmental quality.
A third subtrend, utilization of logging residues will decline from the
present moderate usage to minor usage and will result in a beneficial
environmental effect.
Fire Control (510). This was ranked number five. The prevention and
detection of fires and the use of controlled burning to reduce disastrous
fires will increase as new technologies and research methods are developed.
Wildlife suppression control methods will continue at current usage levels.
Fire control practices, judged to currently have minor adverse implications
for the environment would have no implications (either beneficial or ad-
verse) in 2010, indicating a positive change.
Growth Enhancement (508). This is ranked sixth, and associated subtrends
will have increased usage in all regions in the future. Stocking by
thinning methods and by the elimination of undesirable tree species will
be the most extensively used of these subtrends. All practices associ-
ated with growth enhancement practices will have beneficial implication
for the environment in 2010 compared to their current effects.
Type Conversion (507). Ranked number seven, this is primarily a practice
of the Eastern softwood forests with only minor use in the Western region.
This practice is expected to increase to moderate levels in 1985, but
drop to present levels again in 2010. Its effect upon the environment
will be beneficial.
Pest Control (509). This trend is ranked number eight and is used very
little in any forest region. Biological and chemical agents usage will
increase only slightly by 2010. Selective thinning and salvage logging
to control pests will continue to be a minor practice. The environ-
mental implications of silviculture pest control are very small.
Cutting System (501). Ranked ninth, this trend includes clear cutting,
seed tree cutting, group cutting, selection cutting and shelterwood
and diameter cutting practices. Of these, clearcutting is the most
controversial. Some panelists felt there will be increased opposition
to this practice in the future which will result in a substantial re-
duction in its usage. However, the panel did give a higher extensiveness
rating, five, to this practice for 2010, as compared to a four rating
for 1976. Other cutting systems will vary from minor use to moderate
use in 2010. Cutting systems will have fewer adverse effects upon the
162
-------
environment in 2010, a positive change. It should be emphasized, again,
that silviculture environmental ratings do not consider aesthetics or
ecological disruptions values.
Stand Establishment (506). This trend, number ten, will increase in
use by 2010, with the exception of natural regeneration practices.
Stand establishment practices occur primarily in Eastern hardwood forests
and will decline to minor levels in 2010. Stand establishment practices
will have little impact on the environment.
C. Background Summary
The following descriptions and definitions of trends and management
practices (subtrends) related to silviculture and harvest manage-
ment were provided to the workshop participants as background for the
workshop evaluation. In some cases, the trends or subtrends were modi-
fied to better reflect the panel's judgement for organizing or describing
key trends and subtrends, as noted. This background summary is quasi-
independent of the workshop results as described in parts A and B. How-
ever, it provides appropriate background base data, definitions and des-
criptions of the trends and practices assessed in this portion of the
overall study.
1. Overview and Base Data
Differences in forest ecosystems, land use, and other factors dictate that
the U.S. forest areas be regionally divided to determine specific needs,
trends, and pollutants. These regions are the Pacific Coast region and
the Rocky Mountain region (grouped together in this report under the West
region), and the North and South regions. These regions will be faced
with increasing demand for roundwood and sawtimber products in the future.
Currently 494 million acres are in timberland, but there will be an estimated
5 percent decrease in forest land by 2010. Despite this reduction, increased
demands can be met without annual cut exceeding annual growth. To meet
these demands, there is a need to begin and to carry on intensive forest
management, to apply science and technology, to increase the utilization
of the forests, to protect growing timber, and to prevent further loss of
productive timber lands.
As a result of increased fire protection, tree planting, and other forestry
activities, net annual growth of both softwoods and hardwoods increased
about one third between 1952 and 1970 to a total of 10.7 billion cubic
feet of softwoods and 7.9 billion cubic feet of hardwoods. Exhibits
X-5 and X-6 show total U.S. demand for forest woods projected to
the year 2020 with amounts that can be met by U.S. forests. Based on
the projections, softwood roundwood supplies will increase 29 percent
between 1970 and 2020, hardwood supplies will increase 134 percent,
softwood sawtimber will increase 15 percent, and hardwood sawtimber will
increase 67 percent.
163
-------
Exhibit X-5. Summary of softwood timber demands projected to 2020
iftr
1«2 if
1562 »
!970 11
1130
1990
2000
2C10
20JO
Rotrdwood
TOUT U.S.
fe«n4.
Mill Ml
cubic feet
a.<
S.S
9.7
Cxports
eilllon
Cubic Ifct
0.2
.4
1.2
Ifloorts
it 11 Ion
1.1
1.7
2,1
Oevund
» U.S.
forests
Btnion
ClCTc"T7f~t
7.3
7.2
a.e
Supp'v
fra O.S..
forests -'
Silllm
7.3
7.2
6.8
Supaly-
ie-**nd
balance
lit lit on
'.'.'.
Sl.tl-ier I/
Total U.S.
derano
Billion
39.9
4!. 7
47.6
1970 relative orlces
U.3
13.8
IS. 4
17.2
18.8
2.C
!.l
2.1
2.2
2.2
2.4
2.5
2.S
2.6
2.6
11.9
13.4
14.9
16.3
18.4
10.1
10.7
11.5
11.6
11.6
-1.8
-2.4
-3.4
-5.Z
-6.6
59.3
64.0
68.1
73.3
77.7
exports
Billion
3.6
1.1
1.6
6.9
7.5
S.I
8.3
8.2
Xslno relative prices V
1980
1MO
2000
2C10
2023
11.3
12.1
12.8
13.9
U.8
i.O
2.1
2.2
2.J
2.2
3.2
3.9
4.3
4.4
4.6
10.1
10.3
10.7
11.7
12.4
10.1
10.7
11.5
11.6
11.6
.4
.1
-.1
-.8
S2.4
52.3
50.9
50.7
SO ?
6.9
7.4
8.0
8.2
n i
Imports '
Billion
2.4
4.1
S.S
Dentnd
or. U.S.
8(111 oo
38.1
33.2
45.3
<.(
6.S
6.1
6.3
6.7
59. S
65.3
69..!
75.3
7? I
Supnly
fro* U.SZ/
tllHon
38.1
3B.2
4o.2
48.8
50.9
54.2
54.1
M. 9
Swpoly-
denand
a a ce
StlKw
...
-10.8
-14.1
-15.6
-il.2
-JS.8
8.9
10.8
11.4
11.6
11 R
50.4
48. j
47.5
47. j
4C f
49.8
50.9
54.2
54.1
M Q
-1.5
2.0
6.7
6.8
1 t
telatlve ortces above 1970 averages I/
1930
1990
2000
2010
2020
10.7
12. «
13.7
15.6
17.2
2.1
2.2
2.2
2.2
2.2
3.3
3.8
3.9
3.9
3.9
9.4
10.7
12.0
13.9
15.5
10.1
10.7
11. S
11.6
11.6
.J
O
-2.3
-3.5
49.2
sj. a
57.6
62.4
6< 1
6.8
7.4
8.1
8. 2
R.2
9.6
10. «
10.7
10.6
10.5
46.4
50. «
55.0
60.0
M.n
48.8
SO. 9
54.2
54. 1
?1 1
2.4
.1
-.1
-S.J
.10 j
International 1/4-Inch log rule.
Projections of lupoly ire defined as the irounti of timber that would be available for harveft stralent line basis from actual re.mov»ls 1« 1970 to e. balance wltn jrtwth In tne year
2000 Mi thereafter, (J) rt-oviH on private lands Ir. the Vtst followed trends suo.o.ested ty recent wnloewit >nd ooeritlno practices, tnd
tlla-atle cuti on public lands regained at the 1970 level.
Data for 19S2t 1962, and 1970 are estimates of actual consumption ind harvests end differ somewhat frtw the "trend" estimates shown
tntHt A«««««a«-)t.
Relative ortces nitno. from their 1570 trend levels n follows: Lun*er..i,5 nercent «r ytar-. c'wooi, mtsceHineous cnductt and
fueiwood—l.C percant »r year; paper ind boar^—O.S percent per ye*r. This would wean a «yn«l«t1ve Increase of 62 percent for lumber by
Vie year 2000. and 17 percent for oaMr and boaro".
'Relative prices of lurter end plywood 30 percent, miscellaneous products and fwlwood 15 percint, ind ptper and board 10 percent
•bovu their 1970 average!.
Not*: 0«ta nay not add to totals because of roumttrtQ.
Sources: Data for 1912. 19(2. and 1970 bated on Information oublltned by the. U. S. CcMrUemts af Conearce Mel Ajrleyltur..
•r»)»clteA%t U. 1. 0««*.tv««\ *f Iva.f1ci«\twr*( f«ra»l Urvlce..
-------
Exhibit X-6. Summary of hardwood timber demands projected to 2020
cn
Ittr
"« ^
1962 ''
1970 2'
JtomaWcoo
lottl U.S.
derund
61111*1
3.5 j
1.1
3.0
Exports
Stilton
«/
on
.2
Imports
Billion
0.1
2
Dentnd
or. U.S.
BllUc*
3.S
3.0
.3 2.9
supply
frw U.S.2/
Bllllai
J.5
3.0
2.S
Supply-
der^nd
SUl^or,
...
SMttnftir 1'
Tcul U.S.
demlnd
BIlH^i
11.6
11.7
12.3
Exports
Billion
0.2
.2
.2
Inports
Billion
0.3
1.0
1.3
Dtmani
o> U.S.
Urirn
11.5
10.9
11.2
Supply
fro« U-S...
Billion
11. S
10.9
Supaly-
demmd
(Illltr
...
11.2 :
1970 nelitlvc prl ccl
',S30
1990
2000
2010
JOM
4.3
S.4
6.6
7.9
9.0
.3
.3
.3
.4
.4
.4
.5
.5
.S
.5
4.2
5.2
6.4
7.6
8.9
5.2
6.3
7.<
7.*
7.*
1.0
1.1
1.0
-.4
-1.'
U.7
2C.O
23.1
27.0
30.9
.3
.3
.3
.3
.3
2 1
2.0
2.0
2.0
z.o
15.0
18.3
21.4
25.3
29.2
15.5
18.2
20.6
20.6
20.5
.5
-.1
-.«
-4.7
-6.7
Rlitno relittw or1c«s i'
I960
1990
2000
2010
7920
3.9
4.5
5.4
6.:
7.3
j
.3
.3
.4
.4
.5
.5
.7
.S
.8
3.7
4.3
5.0
S.S
6.9
5.:
6.3
7.<
7.4
7.<
1.5
2.0
2.4
1.6
.5
14.9
16.4
18.0
19.9
21. i
.3
.3
.3
.3
.3
2.0
2.4
2.7
2.3
2.9
13.2
14.3
15.6
!' 4
19.0
15.5
18. 2
20.6
20. 6
20.5
F«l«t1v« ortces ibovc 1970 fvcrcaet I/
1990
1990
2000
2010
2020
3.9
4.3
5.9
7.0
i.:
.3
.3
.3
.4
.4
.6
.6
.«
.6
.6
3.6
4.S
5.6
(.8
9.0
S.2
(.3
7.4
7.4
7.4
1.6
l.S
1.8
.6
-.6
14.1
17.1
20.0
23.6
27.1
.3
.3
.3
.3
.3
2.4
2.4
2.4
2.4
2.4
12.2
15.0
17.9
21. i
25.0
15. S
13.2
20.6
20.6
20. S
2.3
3.9
5.0
3.2
l.S
3.3
3.2
2.7
'.1
-4.S
Int«m«t1oml
log nil*.
6* it projections of Supply an defined I* the amount of Umber that would bt available far h*rvtst1na \f: (1) Forestry proartvia continued
*t 1970 1eveH. (2) tlrbtr rcmoolt In tne £*(t chined on a itriliht-1 1nt bails from actual rcmevill 1n 1970 to * balmct wl U growth, in th«
yiir 2000 and thereafter, 0) rtmov/ali on private lands In th* West followed trendi syr«Jted by ncent mtt,f)inr\i and oocratlnn practices, tni
al1ow*blc cuti on public lands nem*1n«d »t th* 1970 Icwl.
Dili for 19S2. 1962, tnd 1970 art estlinatcs of ketuil consumption And hirvtit» tnd afffcr to^what fro* th* 'trwnd" tst1m«t«l *hawn
Lets tA*n SO Million cubic fe«t.
Relative prices rKInq from thctr 1970 trend levtli «i follo-i; LiMbcr»].5 percent per yt»r; plywood, •Uccllan«ous products Md f^lwooc—
1.0 percent per year; piper and boird— 0.5 percent per year.
Relative prices of lirtur end plywood 30 percent. •Iscillancout products and fuel wood U Mrcent. and o*oer and board 10 percent abavf their
1970 avtrages,
Noli: Data nay not add to tot* It because of rounding.
Sources: Date for IS. , 1962, and 1970 based on infomitlcn published by the U. S. Dtnartntnts «f CnmMixe and Agriculture.
'rejection*: U. S. Department of Agriculture. Forest Service.
-------
In the South region, softwood is the principal product. Management is for
existing pine trees with conversion of some other forest areas to softwood
production. Silviculture in the South region is in the developmental
stages and has the largest growth potential of all the regions. In the
West region, emphasis is on harvesting old growth stands. The North
region is very large and has a wide variety of forest types, but it con-
tributes a smaller proportion of national roundwood production. By 2010,
the North may produce 25 percent of the total U.S. roundwood supplies.
Silviculture practices result in some pollutants that affect environ-
mental quality. These practices include forest fertilization, pesti-
cide application, mechanical forest operations, the construction, main-
tenance, and usage of logging roads, prescribed and slash burnings, and
logging techniques.
Logging road construction, maintenance, and usage and mechanical forest
operations are thought to have the most significant environmental impacts.
Mechanical forest operations can compact the soil and decrease soil pro-
ductivity, destroy wildlife habitat, and leave the soil exposed for po-
tential erosion. Recovery from this soil compaction normally takes 3 to
10 years when soil undergoes freezing and thawing, but it takes much
longer when this does not occur. Increased erosion losses will accompany
logging road construction, and with poor management, stream sediment loads
can greatly increase. Road construction will continue to increase to
2010. Access roads to the national forest system in the West region will
increase to 14,000 Km by 1977 and to 18,000 Km by 2010. These additional
roads will also increase access to public recreational areas.
Pesticide and fertilizer applications occur at infrequent intervals in
forest land. Applications are usually made on a rotational basis with
only a small fraction of the total land area receiving chemical or
nutrients at any one time. During a 30 to 80 year period, each will
receive applications only two or three times. In 1972, only .002 percent
of the commercial forest land received insecticide applications, and while
10.6 million acres are available for fertilization, less than 500,000
acres will receive fertilizer application in ore year. Consequently,
fertilizer and pesticide concentrations are minor compared to those from
productive agriculture usage. They are probably not significant pollutants
of water and air.
Logging techniques result in logging residues which have impacts on the
aesthetic quality of a forest and are potential fire hazards. Water yield
is increased when trees are cut and this may be of benefit if cutting
occurs when or where water is scarce. Where wildlife is affected by
logging practices, each cutting method will favor some species and be
detrimental to others. Clear-cutting practices may, under unusual condi-
tions of steep topography and loose soil underlaid by impermeable rock
formations, result in increased sediment and nutrient loading of streams.
Prescribed and slash burnings change wildlife ecologies, create temporary
air pollution from smoke, and destroy the forest humus and vegetation
166
-------
that is often needed to prevent erosion losses (usually a short term
effect). When vacancies are created in the available growing space by
the death or removal of a species, the remaining vegetation or a new
species quickly fills the vacancy.
2. Trends and Environmental Implications
Forest products originate from a variety of different forest types, a
diversity that results from the distinct ecological conditions that
characterize the various forest regions of the country. Assessments
of the impact on the environment of the silvicultural production system
require an examination of the industry on both the national and regional
levels.
Flow chart. Exhibit X-7 "Silviculture Production Systems" clarifies
the interrelationship of the many factors involved in the silvicultural
production system. This flowchart shows that the environmental impacts
begin at the middle level of the chart under "Resource Management" and
filter downward. The magnitude of these impacts (either positive or
negative) are influenced by developments portrayed at the top level
under "Science and Technology," and how these are, in turn, used at
the next level, "Resource Inputs."
Trends. The specific silviculture practice trends have been grouped in
Exhibit X-8, "Environmentally Related Trends," under the following
headings: (1) timber harvesting, (2) stand control, and (3) damage
control. This grouping provides a convenient framework for the next
step in the analysis, i.e., that of rating the trends in the order of
their overall environmental importance based upon their extensiveness
of use and intensiveness of effect.
Exhibit X-9, Description of Trends and Developments, explains the meaning
of terms used.
Environmental implications. Silviculture practices will have effects
or potential effects upon the environment. Water quality, soil produc-
tivity, air, aesthetics, and ecology will be affected to some extent.
Although regional differences will exist with regard to practices and
the environment, generalized conclusions can be made on environmental
impact.
Sediment losses to streams are associated with road construction, logging
practices, mechanical soil preparations, controlled burns, and occasionally
from clear-cutting. Sediment losses from these practices are usually short
term in effect. Vegetation cover regenerates quickly in forested areas
and after harvesting, a forest area may not be entered for cutting for
several years, so potential erosion situations will arise infrequently.
Forest areas contribute only 14 percent as much sediment as agricultural
croplands. In light of this data, water quality does not usually suffer
significantly from forest sediment sources.
167
-------
Exhibit X-7. Silvicultural production system
CO
S::E:..:E ".D
T£Ci-::.-,iG-v
?^r
S£r
K.TWTS
1
i
{
1 Insecti-
cides
1 i
1 forest >vcn«r.ua-
. i ! tian
S/stun,s i cents !
; i
: " \ "cciian-
"se ization
j
! _ 1 -
ill !
Access i • cul turai
J ! j "ctho;s
;
j j
i i i
1 ! '
1 tur. j t-.cn j 1
t
!
!
Chemicals i
i
i 1
» *
t
fire
Herbicides Retard-
Z.'.tS
1 j ter- 1-lt ; ; Sicijcical Cw.icsl
. ...,pro»t .^ve.o^ , ? | Devciop-
1 sent r.snts ^.-velopnents. r;ci..5 |
! |
(
j
V *'' ^ v ^ t , 7
j £.iecs, Pr . j U ;;! ircyt-ri- j { Micruorg- | 1 jnr ,_ • j Fire
| Sopd*inss, Filiar ; fixing J 1 anisns Herbicides j j * ja"tl" i . Rc.:3rd.
J Clones Sprcys . Syftbiotes Parasites cidcs Ur.ts
U -•* - - - - 4 - i
r | i | ] ] r ^
* A ! «> i •
i ! !
j establish- i
I Ttent Conversion Intermedidte Trea ;:.*u Hardest
r I i
H. ' ' ' i
r— ' 1 i i i i i j !
r-i i 1 I ; '• ' '• • 5 ! • i
j i 1 '!•'"• j • 1 - r
1 ) Ferti- 1 1 ! Ti~icr 1 j Precoii- ICoiawr- | jPrvtec- i fc:ear j (partial ! j Select !
lizorj j i prcviirentj j lh-.nn;ng j j ;n1nnir,g ' n'«e'' 'I '
Y L— .
I
\ ^^"i Wildlife u_.p I'rlMi-y j
Soils Forase 1 Jt:o"«i ....... 1 Forest
j j Potential habitat ; Products J
... 1 J j
! ! !
VXtsa:
Disturb- SediTOn- (onl(,»etlon Yield Flow Quality ««'-
anee Ution j ; d;je!
-------
Exhibit X-8. Environmentally-related trends: Silviculture
TIMBER HARVESTING TRENDS
501. CUTTING SYSTEM USE
a. Clear cutting
b. Seedtree cutting
c. Group cutting
d. Single-tree cutting
e. Shelterwood
502. ACCESS ENLARGEMENT
a. Road construction
b. Road maintenance
503. LOG EXTRACTION METHOD CHANGE
a. Engineering layout
b. Equipment use and development
504. UTILIZATION INTENSITY CHANGE
a. Log extraction residue recovery
b. Log minimum size extension
c. Species use enlargement
STAND CONTROL TRENDS
505. PLANTING SITE IMPROVEMENT
a. Log extraction method prescription .
b. Mechanical preparation
c. Burning prescription
d. Chemical treatment
e. Fertilizer treatment
506. STAND ESTABLISHMENT
a. Species selection
b. Planting material selection and/or development
c. Planting method
d. Stocking control by spacing
507. STAND CONVERSION
a. Species replacement
b. Stand composition enhancement
508. GROWTH ENHANCEMENT
a. Stocking control by thinning
b. Undesirable species elimination
c. Fertilization, chemical composition, method of application
169
-------
Exhibit X-8 (continued)
DAMAGE CONTROL TRENDS
509. INSECT AND DISEASE CONTROL
a. Use of chemical agents: pesticide development
and application
b. Mechanical treatment: selective thinning, salvage
logging
c. Use of biological agents: attractants, repellants,
pheromones, sterilants, parasites
510. FIRE CONTROL
a. Prevention method improvements: hazard reduction,
risk identification, public education
b. Detection method improvement
c. Fire use method improvement
d. Wildfire control method improvement
170
-------
Exhibit X-9. Description of trends and developments: Silviculture
and Harvest Management
TIMBER HARVESTING TRENDS
501. CUTTING SYSTEM USE
a. Clear cutting: The removal in one cut of all trees on
an area. The area may be regenerated from residual re-
production or by natural or artifical methods after
cutting.
b. Seed tree cutting: The removal of all trees in one cut
except for a few of the better seed-producing trees of
desired species which are left well dispersed over the
area to provide seed for regeneration.
c. Group cutting: The removal of all tree size classes in
selected groups up to 2 acres. Regeneration occurs in
the group openings under conditions similar to those
found in small clearcuts.
d. Single-tree cutting: The removal of individual trees
of a pre-determined size, quality, growth rate, and
species. Regeneration is established under the shade
of the remaining trees after each cut.
e. Shelterwood: Any regeneration cutting in a more or less
regular or mature crop designed to establish a new crop
under the protection of the old.
502. ACCESS ENLARGEMENT
a. Road construction: Establishment of forest roadways
for the transportation of forest products and forest
administrative activities.
b. Road maintenance: Activities organized to keep roadways
operable.
503. LOG EXTRACTION METHOD CHANGE
a. Engineering layout; Plans and specifications for log
extraction systems.
b. Equipment use and development: Application of production
machinery to log extraction and development of new machinery
and methods of application.
504. UTILIZATION INTENSITY CHANGE
a. Log extraction residue recovery; Finding ways and
methods of utilizing waste material now left in the
forest after log extraction.
b. Log minimum size extension; Develop methods for using
171
-------
Exhibit X-9 (continued)
smaller diameter and shorter length logs than being
extracted by present use systems.
c. Species use enlargement: Extension of utilization systems
to tree species now considered non-commercial.
STAND CONTROL TRENDS
505. PLANTING SITE IMPROVEMENT
a. Log extraction method precription: Institute specifications
for log extraction methods that will leave the planting site
for the regeneration of a new timber stand in the most favor-
able condition.
b. Mechanical preparation: Use of machinery to establish
favorable site conditions for tree regeneration.
c. Burning precription: Specifications for the use of fire
to establish site conditions favorable for tree regen-
eration.
d. Chemical treatment: Use of chemical formulations to en-
hance site conditions for tree reproduction.
e. Fertilizer treatment: Application of fertilizing prepar-
ations to enhance site conditions for tree reproduction.
506. STAND ESTABLISHMENT
a. Species selection: Organize programs to find tree species
best suited for planting site to be regenerated to forest
trees.
b. Planting material selection and/or development: Organize
programs to determine the best type of planting material
(seedlings, cuttings, etc.) from the species selected.
Establish programs to produce such material.
c. Planting method: Selection of the way to plant tree species
chosen for regeneration program that will produce the most
favorable result under conditions found on the planting site.
d. Stocking control by spacing: Establish specifications for
distance between planting stock that will provide the most
favorable tree stand density considering planting site con-
ditions and potential for survival of planting stock once
planted.
507. STAND CONVERSION
a. Species replacement: Institution of programs to elim-
inate undesirable species and establish in their place
species of greater value.
172
-------
Exhibit X-9 (continued)
b. Stand composition enhancement: Taking measures to encourage or
favor the reproduction and growth of desirable species in a
forest stand.
508. GROWTH ENHANCEMENT
a. Stocking control by thinning: Develop intermediate harvest
programs (before final harvest cut) to attain maximum stand
growth and assure that the growth occurs on the best formed
individual trees or the forest stand.
b. Undesirable species elimination: Orgainze steps to destroy by
by mechanical means, burning or chemical poisoning of species
of no commercial value to favor of crop trees in forest stand.
c. Fertilization (chemical composition, method of application;
Enhance growth potential of forest stand by formulating mixtures
of chemical fertilizers and application to maximize quality and
growth.
DAMAGE CONTROL TRENDS
509. INSECT AND DISEASE CONTROL
a. Use of chemical agents (pesticide development and application);
Develop safe and effective chemical formulations and methods of
application for control of insect and disease infestations.
b. Mechanical treatment ( selective thinning, salvage logging);
Using machinery to eliminate infested material" from forests.
c. Use of biological agents (attractants. repellants. pheromones
sterilants, parasitesTiDevelop and apply natural biological
agents to forest stands to control disease and insects.
510. FIRE CONTROL
a. Prevention method improvements (hazard reduction risk identifi-
cation, public education);Reduce fire danger by Identifica-
tion and elimination of hazardous fuel conditions. Inform the
public to reduce man-caused fires.
b. Detection method improvement; Develop better ways to discover
potentially destructive fires while they are small and control-
lable.
c. Fire use method improvement; Find better ways to use fire to
reduce potential for disastrous, uncontrollable fires.
d. Wildfire control method improvement; Continue and enlarge pro-
grams to develop better strategies, equipment and organization-
al systems for wildfire supression.
173
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Water levels in streams are increased by timber cutting which will benefit
areas where water is scarce and have limited effect in other areas. Cutting
of a large area in a moist climate could create a temporary potential for
flooding situations. Increased water levels are short term and will return
to normal levels with new tree growth.
Logging residues that reach streams create barriers to fish migration,
trap sediment, and make demands on stream BOD levels. Careful logging
management reduce these dangers so that little environmental impact will
result.
Increased water temperatures resulting from streamside cutting will benefit
streams that are too cold for some fish species or growth of adequate food
supplies but may be detrimental to some cold water fish. Buffer zones
between streams and cutting will prevent increased stream temperatures.
Total impact on the environment will be small.
Nitrogen and phosphorus levels in streams are not expected to increase
significantly from the amount of fertilizers used in silviculture. Only
a small forest area receives fertilization each year. The impact of these
nutrients on streams will be insignificant.
Soil nutrient deficiencies resulting from timber cutting may become a
problem with total tree removal practices. Whole tree removals can remove
four and a half times more nutrients from soil than stem removal. Should
this practice increase on a large scale, forest soil could become deficient
in some nutrients requiring increased fertilization. Currently, loss of
nutrients from soil is not an environmental problem.
Soil compaction by heavy machinery during logging operations result in
decreased soil productivity. In some areas, 29 percent of total soil at
a logging site may become compacted. While mechanical operations may not
occur in that area again for several years, the soil will take three to ten
years, minimum, to recover from compaction. Use of lighter, more mobile
equipment, cable systems, and aerial logging will tend to reduce soil
compaction. Total impact of soil compaction is of minor significance.
Forest residues from logging deter from aesthetics and create potential
fire hazards. Whole tree logging, increased uniformity in tree size
and quality, plus clean-up operations minimize residue problems. Environ-
mental impact will be small except in some West region areas where old
growth liquidation coincides with high recreation use of forests.
Air pollution from smoke, dust, and oesticide residues will be short
term and probably produce no lasting ill effect on the environment.
Changes in vegetation, overgrowth, old tree stands, and foliage will
affect the forest wildlife and habitat. While some environmentalists feel
that any change in forests will be detrimental to wildlife, each cutting
practice will benefit some wildlife species and be harmful to others.
174
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SECTION XI
WORKSHOP RANKING OF MAJOR TRENDS ACROSS PANELS
An additional goal of this study was to assess the overall importance of
major trends across the five panel areas. Each panel, having identified
the top five trends in its area, presented these trends to the entire
workshop with the rationale of their importance. The reasons given in-
cluded both the extensiveness of use and the intensiveness of effect of
the trends and their environmental assessments projected to 2010. Also,
the professional knowledge and judgments developed in the panel sessions
were summarized. Each of the five panels was then asked to assess and
rank from 1 to 25 the five major trends from all panels.
The Silviculture and Harvest Management Panel, after long discussion and
with the consent of the Contractor, ranked only the top five trends iden-
tified within its own panel area and did not rank the top trends of the
other four panels. As explained previously, the Silviculture Panel felt
it lacked the expertise to assess the importance of agricultural trends
and its assessment would only dilute the judgments of the agricultural ex-
perts. Also, the Silviculture Panel generally felt that forestry manage-
ment trends should be assessed separately from agriculture due to distinct
differences in the growth cycles of forests vs. agriculture cycles, and
other factors.
Exhibit XI-1 presents the workshop ranking of the twenty major agricultural
trends, five from each panel with the panels as follows:
1. Nonirrigated Crop Production
2. Irrigated Crop Production
3. Feedlot Production
4. Range and Pasture Management
This workshop rank was determined from a summary of the rankings by
Panels 1, 3, and 4. Panel 2 did rank the twenty trends but used a dif-
ferent rating system to arrive at a rank number. This panel began with
the number one trend from each of the four panels and ranked it from one
to four, the second trend of each panel was ranked from five to eight and
so on, although additional shifts were made thereafter. The other panels
ranked the trends in what they assessed as the order of overall national
importance. In theory, all the trends from one panel could have been
judged the most important by the workshop and ranked one through five.
For this reason, the rankings from Panel 2 were not used to arrive at a
final workshop rank for each trend.
175
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Exhibit XI-1. Summary of workshop rankings of major
trends in agriculture and silviculture
Workshop Rank \J
Determined from
Agriculture Trends Panels 1, 3, 4 2/
(104) Runoff and Erosion Control (Nonirrigated) i
(101) Conservation Tilleg^ 2
(203) Improved Water Application 3
(204) Runoff and Erosion Control (Irrigated) 4
(119) Improvement of Seed and Plants 5
(1?0) Scouting and Integrated Controls 6
(121) Developing New Biological and Chemical
Pesticides 7
(319) Feedlot Design for Waste Management 8
(003) Feedlot Size 9
(317) Feedlot Residual Disposal 10
(211) Method of Nutrient Application 11
(406) Grazing Practices: Range fi Pasture 12
(105) Stocking Rates: Range & Pasture 13
(220) Developing Integrated Controls 14
(401) Range & Pasture Renovation 15
(210) Using Plant & Soil Analysis 16
(313) Odor Control 17
(416) Using Increased Resources: Range I Pasture 18
(318) Feed Efficiency and Ration": 19
(417) Range and Pasture Improvement .;0
Silviculture Trends Rank by Panel 5 21
(502) Access to Timber Resource 1
(505) Site Preparation 2
(503) Log Extraction 3
(504) Utilization (Logs & Residues) 4
(510) Fire Control 5
\J Panel 2 was cxxluded from this summary since they used a different ranking system
for the twenty major trends.
2/ Panels:
1) Nonirrigated Crop Production
2) Irrigated Crop Production
3) Foedlot Production
.4) Range and Pasture Management
(5) Silviculture and Harvest Management
176
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Analysis of the Workshop rank of the twenty trends shows that all five
trends from Panel 1, Nonirrigated Crop Production, are ranked within the
first seven places. These rankings indicate that nonirrigated crop pro-
duction trends will be a relatively important agricultural influence on
environmental quality (both beneficial and adverse).
Runoff and Erosion Control (104) was ranked as the number one trend of
the workshop, with Conservation Tillage (101) ranked number two, implying
that both will be of major environmental concern in 2010. Comparisons of
the rankings of the individual panels, show that all three panels ranked
Runoff and Erosion Control, number one, and Conservation Tillage, number
two. (See Appendix for comparisons of panel rankings of the major twenty
trends.)
Trends from Panel 2, Irrigated Crop Production, range from number three
to number sixteen. Improved Water Application (208) and Runoff and
Erosion Control-Irrigated (204) trends were included with the five
trends of Panel 1 to complete the top seven. Trends from Feedlot Pro-
duction, Panel 3, had a high ranking of eight and a low ranking of nine-
teen. The workshop ranks of these two panels indicate that some trends
in each will be very important to environmental quality in 2010. Other
trends from these panels will have an effect, but were judged to have
neither the extensiveness of use nor the intensiveness of effect upon
the environment as compared to other trends.
Pasture and Range Management trends, Panel 4, were clustered in the bottom
half of the twenty. These trends ranged from number twelve to number
twenty.
The top five trends of Silviculture and Harvest Management, Panel 5,
are included in Exhibit XI-1. While Silviculture did not rate agri-
cultural trends across panels, the other four panels did rate silvi-
culture trends along with their trends. In summary, these rankings
placed silviculture trends in the bottom half of the trend placement.
In general, the Workshop concurred that substantially more quantita-
tive measures are important before the environmental implications of
silviculture can be appropriately cross-ranked with agriculture.
Exhibit XI-2 shows the rank each trend had within its panel, the rank
each trend received from its own panel when integrated into the top
twenty, and final workshop rank of each trend. Panels 1 and 2 changed the
relative order of their trends when putting them in the major twenty.
Panel 1 reversed the order of two trends, while Panel 2 changed the order
of four trends, and combined trend 204 with trend 104, and trend 220 with
trend 120. The rankings by Panels 1 and 4 of their trends closely paralleled
the final workshop rank of these same trends.
177
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Exhibit XI-2. Panel's ranking of their top five trends within twenty major trends
oo
Panel
1. Uonirrlgated Crop
Production
2. Irrigated Crop
Production
3. Feedlot Production
4. Range ! Pasture
Kar.aceir.ant
5. Silviculture and
Harvest Ksnagener.t
Trend
(204) Runoff 4 Erosion Control
(119) Imorovement of Seeds 5 Plants '103 + 114}
(101) Conservation Tillage
(1JO) Scouting & Integrated Controls (112 + 117)
(122) Developing New Biological and Chenical
Pesticides (115 + 115)
(208) Improving Water Application
(204) Runoff 5 Erosion Control
(211) Methods of Nutront Application
(220) Developing Integrated Controls
!210) Using Plant S, Soil Analysis
(303) Feedlot Size
(319) Feedlot Design for Waste Management (:0« + 311 + 312)
(317) Residual Disposal (312 + 315)
(313) Odor Control
(313) Feed Efficiency & Ration (302 t 305)
(406) Grazing Practices: P,ange 4 Pasture
(4C5) Stocking Rages
(401) Range & Pasture Renovation
(416) Using Increased Resources (411 + 415)
(417) Range & Pasture Iirprovenent (402 + 4CK + 407)
(502) Access to Tir,be" Resource (Woods)
(505) Site Preparation
(503) Log Extraction
(504) utilization (Logs 4 Residues)
(510) Fire Control
Initial Panel
Rank of Top
Five Trends
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1 3/
2
3
4
5
Panel's P.ank
of The:r Trends
in Twenty
1
3
2
6
7
2
iy
6
52/
12
3
5
6
15
13
12
13
14
18
19
Workshop
Final Rank
of Trends
1
C.
2
6
7
3
4
11
14
16
9
8
10
17
19
12
13
15
18
20
I/ Ranked Xua&er 1 along with (104).
y Ranged N'urber 5 alr.ng with (120).
3/ Silviculture trends were rated separately by silviculture panel only and arc not Included in top twenty trends.
-------
Individual participants were also given the opportunity to rank the
top trends without regard to panel preference. While emphasis of the
workshop was on judgements and assessments of panels and not on indi-
viduals, note should be made of the summary of rankings by the indi-
vidual participants (see Appendix). This assessment shows a ranking
that follows the overall Workshop ranking very closely, with the biggest
change in any rank by only three places. Individual participants would
seem to have placed confidence in the overall Workshop rankings of the
major trends.
Participants were also given the opportunity to integrate other trends
from their panel into the top twenty. Of most significance was the
Wind Erosion Control (106) trend from Panel 1. Several panel members
thought that this trend was important enough to be considered in the
top twenty trends. This is a good reminder that the twenty major
trends in agriculture are "limited" to only five from each panel—as
prescribed by the procedures of the Workshop. The major twenty trends
presented should not necessarily imply the top twenty trends, but rather,
they do indicate relative importance under the terms of the Workshop.
179
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SECTION XII
CONCLUSIONS AND RECOMMENDATIONS
In reviewing the contractor's preliminary findings, the Evaluation
Workshop provided the desired assessments of environmental implica-
tions of trends in agriculture and silviculture. Development Planning
and Research Associates, Inc. reached the following conclusions re-
garding the workshop's judgements. Also, recommendations concerning
future efforts with this type of workshop assessment are presented below.
A. Conclusions
In reference to the preceding summarization of the workshop findings,
four main conclusions are highlighted:
1. Panel Rankings. Each panel reached a consensus opinion of how the
trends or developments in its area should be ranked relative to its
associated environmental effects. These panel results are clearly a
key conclusion of the workshop, and the U.S. Environmental Protection
Agency can advisedly follow the panels' ranking of these major trends
realizing, importantly, both the beneficial and adverse dimensions of
the component subtrends within each trend.
2. Workshop Rankings. The workshop also ranked five major trends from
each panel area (agriculture panels only). This ranking, from 1 to
20 for the four agriculture panels, was the second important result
of the workshop for it establishes an overall priority of concern
for environmental effects emanating from the apricultural sector.
The silviculture sector was regarded as distinctly different from
the agriculture sector, primarily due to the longer growth cycle of
forest production. Consequently, the trends of silviculture were
not officially cross-ranked with the trends of agriculture—although
the agriculture panels did integrate silviculture trends with their
trends and placement of silviculture trends was in the lower half of
major ranked trends. Certain aesthetic, wildlife habitat, and eco-
logical issues associated with silviculture production and harvest
management were not adequately resolved within the silviculture panel
(which would add to this panel's ratings); and, thus, cross panel
comparisons were, perhaps, indeed premature.
180
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3. Relative Ratings Within Panels. A third valuable result (and con-
clusion) of the workshop was the assignment of adjusted ratings, AR,
to each of the panels trends (which was used to determine each trends
ranking). These ratings, as presented above, are a further enumer-
ation of the panel's judgement of the relative environmental importance
of each of the trends. (Note, however, that these panel ratings should
not be compared across panels, only within each panel.)
As required by the workshop, the panels were to present a composite
panel rating. Individual judgements within a panel may have differed
from the final ratings; however, the panel's conclusions were the
primary results sought by the Workshop.
4. Diversity of Segments. Agriculture and silviculture represent major sec-
tors of the economy which are diverse not only in management and produc-
tion procedures but also in their environmental implications. The major
environmental concerns in agriculture involve direct effects on soil, air,
and water quality and indirect effects, primarily on the human food chain.
In silviculture, considerable concern surrounds the indirect environmental
effects involving ecology, aesthetics, and recreation.
Substantial differences in environmental implications exist among
specific segments within agriculture. Crop production activities
are non-point sources of pollution; feedlot operations are classified
as point-sources. Range and pasture management take on aspects of
both agriculture and silviculture. The problems and concerns of each
of the segments are not only diverse in operations but are also, in
many cases, regionalized. Irrigated crop production occurs pre-
dominately in the western 17 states while nonirrigated production
occurs primarily in the eastern United States. Types of timber har-
vesting vary significantly between regions. Because of this diversity
in operations, environmental implications, and regions involved, the
various segments will require focused attention as a requirement for
an effective environmental program.
B. Recommendations
As a byproduct of the workshop experience, and not as a planned result,
several recommendations can be offered for future efforts to turther
the assessment of the environmental implications of trends in agri-
culture and silviculture. The suggestions are briefly presented below.
Special Note. These recommendations do not_ include DPRA's input to
EPA concerning Phase II of this overall study, i.e., evaluation of the
environmental impacts (vs. implications) of selected key trends. How-
ever, this Evaluation Workshop Summary will be the principal basis for
DPRA's recommendations for Phase II.
181
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1. Regionalization of Trends. While it was anticipated that regional
variations in trends or developments would exist, the panels would
have generally preferred that the rating system be regionalized so
that known regional differences could have been pinpointed. Further
studies of this type should isolate important regional variations in
trends.
2. Segmentation of Panel Areas. In some instances, a further segmenta-
tion of a panel's area, e.g., species categories in Livestock, or
ranges plus pastures in Range and Pasture, would have been desirable.
This was largely accomplished by the Range and Pasture Panel by first
assessing each component—which were then aggregated. However, it
appears that providing for segmentation within the prepared forms
would generally be desirable, although, thereafter, the aggregation
process was found feasible.
3. Additional Trends. Because of the time constraints for completing
the required forms, most panels had little time to consider the addi-
tion of trends (and subtrends) to those provided by the Contractor.
This is not to say that the major trends were not identified and
rated; however, a more elaborate enumeration of trends, and especially
possible developments, could have been generated by the panels.
The Contractor recommends that future efforts include time allotments
for the generation of additional trends and probable developments
which may have significant environmental implications.
Related to this limitation, time was also not available to pursue
the relative importance of secondary trends, e.g., trends 6 to 10,
of each panel area. Individual summaries were obtained, but no
overall workshop evaluations were possible. To some extent the
relative adjusted ratings may be used to approximate the overall
ranking of secondary trends, but further assessment is warranted.
4. Quantified Environmental Data and Environmentalist Representation.
There was general agreement that sufficient quantitative data on the
environmental effects of specific agricultural and silvicultural prac-
tices (trends or subtrends) do not generally exist. When available,
such data tend to be site specific (a desirable attribute), but the
consequences cannot be readily generalized to regions or the nation.
Obviously, more quantified data are desired, but in the meantime
considered value judgements are needed.
The workshop format was designed to predominantly include professionals
within agriculture and silviculture who are knowledgeable both of the
trends and of associated environmental effects. Presumably more em-
phasis could be given toward inclusion of environmental professionals
whose emphasis is not necessarily agriculture or silviculture technology
or production. Thi.s may have altered the focus of the workshop, however.
182
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The plan of study is to incorporate both more quantitative data (as
available) and more environmentalist input in the Phase II-Evaluation
of the impact (vs. implication) of selected trends in agriculture and
silviculture. Also, however, future workshops which have either a
narrower focus, and/or a more established ordering of key trends may
well benefit from the addition of more professional disciplines which
would broaden the scope of understanding of environmental effects of
trends and developments.
5. Public and Private Support of Trends. Throughout the panels'
evaluations, a recurrent theme was that if a given trend is
fostered through public and private channels, then the environ-
mental implications will be major, etc. In other words, various
trend assessments were conditional evaluations such that if "A"
happens then "B" will follow. The workshop instructions were for
the participants to make collective judgements as to the expected
outcome of each trend given their knowledge of current and expected
socio-economic-political conditions. In many cases, the underlying
trends or possible developments do require continued support by
local-state-federal governments if the trends are to be realized.
Future workshops might benefit from a more explicit evaluation and
summarization of associated supporting legislation to foster selected
trends and developments. This workshop relied primarily on the know-
ledge and measurements made by the respective panel participants.
6. Rating System Improvements. Each of the panels utilized the rating
system definitions effectively to determine the desired rankings
within their panel area. However, the rating system, as defined,
allowed for variation in use when assessing changes over time.
As a recommendation, the procedures utilized by the Silviculture
Panel most nearly capture the intent of the workshop—which assesses
the 2010 environmental implications as compared to 1976 (current)
by first "defining" the current period rating. Subsequently, the
changes in environmental effects are more rigorously defined.
The other panels implicitly defined current period environmental effects
but assessed changes only. Again, each panel resolved the rating
system issues to their own satisfaction so that their ratings within
panels are valid. The across-panel ratings were specifically deter-
mined without reliance on the adjusted ratings which were stressed
as panel values only.
7. Time Frame. The time frame for the assessment was from 1976 to 2010.
A short-term period, i.e., 1985, was also designated vs. the long-
term period of study, i.e., 2010. The workshop focused on the 2010
period only due to the limited time available for review by the par-
ticipants. Further study of the short-term, as well as long-term,
data contained in this summary is warranted and planned in Phase II.
183
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Further research in this area of study may justifiably include greater
emphasis on the distinction of short-term vs. long-term environmental
implications of trends in agriculture and silviculture. An expressed
observation by the workshop itself was that the "beneficial" results
by 2010 may not be fully realized by 1985; and, hence, the short-
term effects may tend to be "adverse." This result could compound
the environmental issues associated with trends in agriculture and
silviculture.
184
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SECTION XIII
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Erosion," Environmental Science and Technology, 1(9): 740-744,
1967.
Wiersma, G. B., H. Tai, and P. F. Sand, National Soils Monitoring Pro-
gram for Pesticide Residues, FY-1969, U.S. Environmental Protec-
tion Agency, 1972.
Wiersma, G. B., F. F. Sand, and E. L. Cox, Pesticides Monitoring Journal.
5: 63-66, 1971.
Williss, G. H., et. al_., "Losses of Duiron Tinuion, Fenac, Trefluralin
in Surface Urainage Waters," J. Environmental Quality, 4(3): 399-
402, 1975. :
Wittwer, S. H., "Food Production: Technology and the Resource Base,"
Science. 188 (4888): 579-584, 1975.
188
-------
APPENDIX A
THE EVALUATION WORKSHOP: PURPOSE AND PROCEDURES
The Contractor's preliminary assessments of trends and developments in
agriculture and silviculture which have potentially significant environ-
mental implications were submitted to a workshop evaluation in order to
more usefully serve the needs of the Environmental Protection Agency
(EPA). Those identified trends (and/or others specified by the workshop)
were delineated on a priority basis with respect to their environmental
implications—either beneficial or adverse. This was the principal task
of the Evaluation Workshop.
As is readily understood by those who are familiar with the breadth and
complexity of environmental issues, it is not possible to adequately
document and quantify all the direct, indirect and synergistic impacts
of pollutants from diverse sources that occur locally and regionally
throughout our nation. Consequently, any assessment to provide a priority
ranking of major environmentally-related trends in agriculture and silvi-
culture must necessarily be based on informed judgments of qualified
individuals and groups.
The participants of the Evaluation Workshop were selected because of
their individual experience and expertise involving agricultural or
silvicultural production and environmental implications. Collectively,
these participants provided informed, and necessarily, qualitative -
subjective judgments as had been requested by EPA through this study.
A. Purpose of the Evaluation Workshop
The primary purpose of the Evaluation Workshop was to rank the major
environmentally-related trends and developments in agriculture and
silviculture which are expected during the 1976-2010 time period. The
basis for this assessment included specifically the Contractor's pre-
liminary data findings. However, the workshop participants further
assessed and modified,where necessary, the trends and developments as
selectively defined by the Contractor.
Phase II of this study will incorporate the findings that emerged from
the Evaluation Workshop.
B. Procedures for the Evaluation Workshop
The workshop participants were divided into five panels for the detailed
trend assessments. These panels represented specific segments of agri-
culture and silviculture:
A-l
-------
Agriculture
1. Nonirrigated Crop Production
2. Irrigated Crop Production
3. Feedlot Production
4. Range and Pasture Management
Silviculture
5. Silviculture and Harvest Management
Workshop participants were involved in their respective panel sessions
and in general sessions to establish major trends in their specific areas
of expertise and to assess the overall relative importance of major trends
across the five panel areas.
To accomplish the overall objectives of the Evaluation Workshop in the
time available, a formally-structured evaluation procedure was defined.
This procedure involved two main components:
1. A rating system
2. A series of forms
The rating system is explained in detail in Exhibit A-l. The essence of
this rating system is that each trend (or prospective development) was
to be rated in relative terms for both "extensiveness of use" and "inten-
siveness of effect" to yield a multiplicative rating:
Environmental Implications Rating = Extensiveness of Use x
Intensiveness of Effect
or,
R = E x I,
as defined in Exhibit A-l. Again, this procedure is a relative rating
system, but it is suitable for assessing priorities as desired for the
present study.
The series of forms, illustrated for Panel 1, are essentially worksheets
for each panel (copies for each participant were provided) such that when
the forms were "completed", the required tasks were accomplished.
In total, each panel had seven forms. These seven forms, numbered 1 to 7,
e.g., Form 1-1 to Form 7 for Panel 1, were completed sequentially as
explained below.
A-2
-------
Exhibit A-l. Rating system definition for the assessment of environment
Implications of trends In agriculture and silviculture
Environmental
Rating
R
+J1-25)
Extenslveness
of Use
(E)
0-5)
X
X
Intenslvcness
of Effect
(0
i d-5) y
where,
Rating:
Factor 1:
An Index of the overall environmental significance of a
trend or development 1n terms of both the scope of the
tr;nd (E) and the seriousness ot" the environmental impli-
cations (I) of the trend. R (s the product of the ratings
for E (1 to 5) and for ! (+_ 1 to 5) as defined below.
Extenslveness of use of the trend (current or projected).
Criteria shall Include:
(1) geographic scope (national vs local)
(2) degree to which total acreage or sector ouput
of the nation Is Impacted
(3) the economic Importance of the trend (short-
term and/or long term)
(4) Other (define)
A rating of 1 to 5 shall be qualitatively and subjectively
determined for each trend or development as follows:
factor Z:
Rating Scale
V
2
3
4
S
Description
nlnor significance
moderate significance
major significance
Intenslveness of effect of the trend (Including Its persistence
and potential IrreverslblHty of effect). Criteria shall Include:
huiti.ii health effects
ecological system disruptions
wildlife and wildlife habitat effects
recreation effects
aesthetic consequences
agricultural (and sllvlcultural) production effects
other (define)
A rating of +(1-5) shall be qualitatively and subjectively
determined 'or each "unit" of production to •••Men the trend or
development applies, I.e., Irrespective of scope of the trend,
». plus(+) rating denotes 'a positive or beneficial effec'. on the
environment (on balance); whereas, a negative (-) rating denotes
a negative or adverse effect -on the environment (on balance).
The ratings shall be as follows:
Rating Scalp
+ or -
+• or -
+ or -
+ or -
+ or -
1
2
3
4
5
Description
minor significance
moderate significance
major significant
'(+) • beneficial, (-) • ad-erse
£»ch factor shall be rated on a scale from 1 to 5 U has positive values only
whereas I may .-. either positive or ne^tlve. representing beneflc lal or '"verse
e-vlronmental effects, respectively . These factors, ^en multiplied, may yield
an environmental rating. R, from + (1 to 25 . Re atlvely high abjolu^e ratings
beneficial or adverse on an aggregate basis. Special remarks should ac-
ompny Iht o erall r»"ng 1n the c«e of conflicting/offsetting ton. ,< : al and
adverse environmental components to explain the resolution of the conflict.
Each selected trend or development In agriculture and silviculture 1s to be
ffl SSJdS r?^^;rs'^qu^I^vel
related trend* In agriculture and silviculture.
A-3
-------
An overriding constraint was the amount of time that each panel had to
complete its assessments on each form. (Note—Panel Chairmen were
designated to preside over panel discussions and assure timely completion.
Any "minor" trends could be dropped from a detailed analysis to conserve
time, but each panel had to so-define such trends by consensus judgment.)
The following description of the steps of the workshop were distributed
to the participants and defined the use of each of the forms, the time
allotted for each form, and key points regarding the step or form. Also,
Development Planning and Research Associates or the Tuolumne Corporation
and EPA personnel were available at each panel and general sessions to
assist with procedural matters.
General Session 1
(Wed. 8:30-10:30 a.m.)
Panel Session I
(Wed. 11:00-12:00 a.m.)
Panel Session II
(Wed. 1:00-5:00 p.m.)
Step 4:
Introduction
Overview of agriculture and
silviculture
Summary of procedures
Panel briefing and orientation
Form l--Each panel rate trends
on cxtensiveness of use (E)
Rating values range from 1 (minor)
to 5 (major) as uefineu in
Exhibit 1
Note the component trends' "E"
value later needed for 2010
only.
Finish Form 1
Form 2--Each panel rate trends on
intensivenes- of effect (I)
Rating values for component (a, b,
c,...) trends range from ±1
(minor) to ±5 (major) where + =
beneficial changes and - = adverse
changes in the environmental
effects.
The (I) values are to reflect changes
in effects relativ" to current
(1976) conditions from implementa-
tion of the trend or development,
either + or -.
Note (I) is essentially independent
of time per unit affected, e.g.,
acre; however, use 2010 basis
if (I) affects change over time.
See Exhibit 1 for definitions.
A-4
-------
Panel Session III
(Wed. 7:30-9:30 p.m.)
General Session II
(Thurs. 8:30-12:00 a.m.
1:00-2:30 p.m.)
7: .
Panel Session IV
(Thurs. 3:00-5:00 p.m.)
Form 3--Panel to integrate infor-
mation from Forms 1 and 2 to
derive the "absolute" environ-
mental implications rating R
as shown on Form 3.
Panels determine adjusted ratings
(AR) for any trend for which
further assessment is warranted.
Adjusted ratings (AR) reflect the
overall relative panel ratings
of trends.
Priority rankings of trends are
implicit with the highest abso-
lute value the most important
of those assessed.
The AR rating may be the same as
the environmental implications
rating, R. A rationale for any
changes should be cited.
Form 4—Each panel will determine
the top five trends and their
ranking, and the next five most
important trends and their
rankings.
These trends, and particularly the
top five trends, from each panel
will be submitted for overall
trend assessment.
Contractor will summarize top
trends from each panel for dis-
tribution.
The Workshop will meet in general
session to review and discuss
each panel's findings.
The five panel chairmen will
present, explain and lead dis-
cussions over the 5 most important
trends as determined by each panel.
The second five most important trends
may he ic'entifieri; but discussion
must be limited.
Form 5--Each panel will rank the
twenty-five trends (five from
each panel) following the earlier
general session explanations and
discussions.
A-5
-------
Panel Session IV (Con'd) . Remarks on key factors involved
in the final ordering (priority
ranking) are to be highlighted.
. The final adjusted ratings (AR)
from each panel will be summarized
for cross reference, but these
values do not necessarily imply
an overall rating.
General Session III Step 9: . Form 6—The contractor will prepare
(Fri. 8:30-11:30 a.m.) a summary of the results of all
panel's rankings of the twenty-
five major trends (five from each
panel).
Panel Chairmen will briefly present
the rationale for their panel's
rankings.
Step 10: . Form 7--Each participant will in-
dividually rank the twenty-five
trends following the concluding
rationale and discussion of all
panel rankings.
. Each participant is free to rank
the twenty-five trends according
to individual preferences without
consensus from his own panel.
. Results will be tabulated subsequent
to Workshop.
Step 11; . Wrap-up of Workshop
. Concluding remarks
. Adjourn
Following the Evaluation Workshop, Development Planning and Research
Associates, Inc. prepared the present summary of findings and conclusions
of the workshop. Summary materials are to be distributed to the workshop
participants and to EPA. These findings will also be inputs into Phase II
of the study as previously discussed.
Modifications of the above procedures, necessitated by the work of Panels
2 and 5, are indicated in Sections VII and X of this study.
A-6
-------
N'onirrigated Croo Production Panel •
Form 1-1
Page-.l of 5
TRENDS ASSESStfENT--EXTINSIVENESS OF USE
Trend
Rating (E) ±/
Current1985 20lff
Remarks
101. Conservation Tillage
a. No-tillage
b. Reduced tillage
JL J_
JL. 2-
/s
c.
102. Crop Sequencing
a. Mono-crop sequence / / 2,
b. No-neadow crop sequencing / / /
c. Relay cropping 'I _£_ 3 \ ?\
d. Double cropping ^2 3 V
e. _
103. Seed/Plant Improving
a. Weather resistance / J 2- _
b. Salt tolerance ^ _£ _.!_ _
c. Production efficiency Ji <2. ^L
d.
(Continued. . .}
*/ 'Extensiveness rating (E), with values ranging from-+l (minor) to +5 (major), as explained in the Rating System
~ Definition Exhibit 1.
v
v
-------
Nom'rrigated Crop Production Panel
>
ENVIRONMENTAL ASSESSMENT—INTENSIVENESS OF EFFECT
Form 2-1
Page- 1 of 5
Trend
Overall I/
Degree of Effect Intensiveness
Water "ATrScTIOther : Rating (I)
101. Conservation Tillage
a. No-tillage
b. Reduced tillage
c.
102. Crop Sequencing
a. Mono-crop sequence
b. Nc-meadow crop sequencing
c. Relay cropping
d. Double cropping
e.
103. Seed/Plart Improving,
a. Weather resistance
b. Salt tolerance
c. Production efficiency
d.
-t-3 & -
•*a & o &
& &
o
- >' & o & -3 &
1 _0.& -fl &
& _0 & -f/ &
& 0 & -f I &
& & &
tj
''emarks
\\
(Continued. . .}
Intensivensss rating (I), with values ranging from ±1 (minor) to ±5 (major), as Explained in tha Rating System
Definition Exhibit 1. Use 2010 time period only as the basis.
-------
>
Nonirrigated Crop Production Panel Form 3-1
Page 1 of .5
TREND/ENVIRONMENTAL IMPLICATIONS ASSESSMENT
Original Values _!/
Trend E- x I = R
101. Conservation Tillage &>
a. No-tillage J? + 3_ d>
_
b. Reduced tillage B -+3. 6>
c.
102. Crop Sequencing | 4 [
a. Mono-crop sequence 3. -3. _4
b. No-meadow crop sequencing / -2 3.
c. Relay cropping 3 .+ | 3
d. Double cropping 4 -f 2. S
e.
103. Seed/Plant Improving £.
a. Weather resistance «2 -tl =2.
b. Salt tolerance -2. -fi ^.
c. Production efficiency 5. -fl A
d.
Adjusted Values 2/ Adjusted
; x I AR Remarks 3/
\X>
\N
\\/v
^~\ ^^
r/' \ ^
•9 ^ \^
\ ^V\\
X/^v NN^
A . X^X
^vX
*^ \ \
ft/*' ^? V
T ' "" VlIZl^N
^ — -^
II E is extensiveness of use rating, I is intensiveness of use rating, R is environmental implications rating, as
explained in Rating System Definition Exhibit I.
2J Changes can be made to reflect the panel's overall relative ratings of trends. AR should be reflective of the
final rankings.
3/ Additional remarks may be made on back or on attached sheet.
-------
Mf
_ Panel
OF MAJOR TRENDS A,','D ASSOCIATED PANEL RATING
Form 4
Page 1 of 1
Trend Number and Title
1. (HB )
2. (/o/.)
3- ( //& )
4.
5.
6. ( )
7-L
8. (
9. ( )
10. ( )
*fr
r
Adjusted
Rating (AR)
Panel Remarks
Participant's Notes:
-------
Panel
PANEL RANKINGS OF TWENTY-FIVE MAJOR TRENDS
Form 5
Page 1 of 2
Trend Number and Title I/
Panel's Adjusted
Rating (AR)
Remarks
2. .207)
•
3-
8. (
9. (
io. L
11. (
12. L
13. (
14. f
15. L
A\
\\M\\
^
I/ Panel's rank 25 trends in their preferred order.
-------
Panel
PANEL RANKINGS OF TWENTY-FIVE MAJOR TRENDS (Continued)
Form 5
Page 2 of 2
Trend Number end Title
Panel's Adjusted.
Rating (AR)
Remarks
16. ( )
22. (
23. .£
24. (
17. ( )
18. ( )
19. ( )
20. { )
21. ( )
Ak
UA
W
25. ( )
-------
General Sunmary
SUMMARY OF ALL PANEL'S RANKINGS OF TWENTY FIVE MAJOR TRSNOS
Form 6
Page 1 of 2
Trend Number and Title
PanVTs Rankings
2
Sum 2/
of Ranking
Participants
Remarks/Notes
1. (//8)
2.
3.
4. k2Q7)
5. (_>o/_
6.
7. ( .1 "
8. 1
9. i.
10. {_
11. I
12. {
(Continued. . .)
_!/ Panels: (1) Non irrigated Crop Production
(2) Irrigated Crop Production
(3) Feedlot Production
!4) Range and Pasture Management
5} Silviculture and Harvest Management
2/ The sum of the individual panel's rankings yield a value such that the lowest sura will be ranked first,
the next lowest sum will be ranked second and so on.
-------
General Summary
SUMMARY OF ALL PANEL'S RANKINGS OF TWENTY FIVE MAJOR TRENDS (Continued)
Form 6
Page 2 of 2
Trend Number and Titie
Panel;s Rankings
Sura JJ
j 45 of Ranking
Participants
Remarks/Notes
13.
14.
15.
1.6.
17.
18.
19.
20.
21.
22.
23.
24.
25.
<\
-------
INDIVIDUAL PARTICIPANT'S FINAL RANKING OF TWENTY FIVE MAJOR TRENDS
Form 7
Page 1 of 2
i-*
en
Trend Number and Title
Workshop
Rank I/
Individual 2f
Participant Rank
Remarks 3/
1. (//fl )
2.
3. (Jfofl )
4.
5.
6.
7.
3.
9.
10.
11.
12.
13.
14.
15.
(lOnC^OtA^^^ll^JU
( 314 ) BtA&c^L /Wjft2T
/ \ ^
) —
( )
( ) ^ — ^- — ^_
( ) ^"^^
( ) • — *"
^-^~^^ -^
( ) ^"^
^^___^
X /
J___
( }
(Continued. . .)
12
13
14
15
i
_
\
I/ Workshop rank as determined from five panel ratings.
2/ Participants are "free" to rank according to own preference without consensus from own panels.
3/ Reasons for major shifts are requested.
-------
INDIVIDUAL PARTICIPANT'S FINAL RANKING OF TWENTY-FIVE MAJOR TRENDS
Form 7
Page 2 of 2
Trend Number and Title
Workshop Individual
Rank Participant Rank
Renar! .-:
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
(
(
(
(
(
(
(
(
(
(
)
)
)
)
)
,
)
)
)
)
15
s
Name :
(Optional
! Area of expertise:
Panel:
-------
APPENDIX B
THE EVALUATION WORKSHOPS DETAILED PANEL RATINGS
While evaluations and summaries of the workshop findings are contained
within the present text, additional supporting data are provided in this
Appendix. Panel rankings of the twenty major agriculture trends, in-
dividual participant rankings (voluntary) of these same twenty trends,
and individual rankings (voluntary) of the second five trends (#6-#10)
are shown in Exhibits B-l, B-2 and B-3, respectively
Specific workshop procedures are reviewed in the text and are not dis-
cussed further here. However, a brief discussion of all exhibits and
other Appendix material is presented below.
Exhibit B-l—Summary of all panels' ranking of twenty major trends.
An overall workshop rank was determined of the five major trends from
each of the agriculture panels (Panels 1, 2, 3, and 4). These trends
were ranked across panels, by each panel, in the order of assessed im-
portance. While all four panels ranked each trend, the final workshop
rank was determined from the rankings of Panels 1, 3, and 4 only. The
rankings by Panel 2 - Irrigated Crop Production were excluded from the
workshop rank because a unique ranking system was used. Basically,
Panel 2 ranked the number one trend from each of the four panels from
one to four, the second trend of each panel was ranked from five to
eight and so on. The other panels assessed and ranked the overall en-
vironmental importance of each trend regardless of its panel's ranking.
The actual rankings given to each trend and the sum of these rankings
are shown in Exhibit B-l.
As stated in the text, silviculture trends (Panel 5) were not officially
cross ranked with agriculture trends. The Silviculture Panel felt there
were distinct differences in the growth cycles of forests and agriculture
and that they also lacked the expertise to assess the relative importance
of many agriculture trends. For these reasons, the trends from silvi-
culture were not integrated into an overall workshop rank with agri-
culture's major trends.
Exhibit B-2—Summary of individual participant's ranking of twenty
major agriculture trends. Each participant from the agriculture panels
(Panels 1, 2, 3, and 4) was given the opportunity to rank the twenty
major agriculture trends according to his own preference without consensus
A-17
-------
from his own panel. Ten participants responded and their rankings of
each major trend are given in Exhibit B-2. Although an overall rank
for each trend as determined by the individual responses is shown, it
is stressed that the assessments by the panels, not by individual
participants, were emphasized in the Workshop.
Exhibit B-3-- Summary of individual participants integration of second
five trends (#6-#10), as identified by his panel, into major twenty
trends.The workshop procedures allowed for five trends from each
panel to be ranked in the major twenty trends. Other trends, ranked six
through ten, within a panel, could have been judged important enough to
be cross ranked in the major trends. However, these judgements were not
presented within the structured portions of the workshop. Rather, on a
voluntary basis, each participant was allowed to integrate any or all
of the second five trends (#6-#10) identified by his panel into the
major twenty trends. Out of seven responses, Wind Erosion Control (106)
from the Nonirrigated Crop Production Panel was most frequently given a
ranking in the major twenty.
Form 3. Environmental Implications Assessment of Trends (Panels 1 to 5).
The environmental implication assessment (form 3) for all five panels
is included for reference. Extensiveness of use (E), intensiveness of
effect (I), environmental ratings (R), and adjusted ratings (AR), as
assessed for each trend (subtrend), are shown below. All written comments
made by each panel in reaching these trend ratings (taken from forms 1, 2,
and 3) have been summarized for each trend. The format for the environ-
mental implications assessment of silviculture trends differs slightly
from that of the other four panels. The Silviculture and Harvest Manage-
ment Panel gave an environmental implication rating (R) to trends for
both 1976 and 2010. The 1976 rating was subtracted from the 2010 ratings
to get the change in rating, and finally an adjusted rating was given each
trend.
Workshop forms (1 to 8) and instructions. The structured forms (1-8)
used by the workshop panels to assess trends were included in the previous
Appendix A. Additionally, the workshop participants were given instruc-
tions and guidelines to use in completing these forms; these instructions
are also contained in the previous appendix.
A-18
-------
Exhibit B-l. Sunmary of all panel's rankings of twenty major trends
to
Work-
snap
Rank Trend Number and Title
1. (104) Runoff I Erosion Control (Honirrigated)
2. (101) Conservation Tillage
3. (20&) Improving 'd.-.ter Application
4. (204) Runoff 8 Erosion Control (Irrigated)
5. (119) Improvement Plants * Seeds
6. (120) Using Scouting & Integrated Controls
7. (121) Developing New Biological & Chemical
Pesticides
3. (319) Feedlot Design for Haste Management
9. (308) Feedlot Size
10. (317) Feedlot Residual Disposal
11. (211) Method Nutr-.snt Application
12. (406) Grazing Practices: Range & Pasture
13. (405) Stocking Rates: Range & Pasture
14. (220) Developing Integrated Controls
15. (401) Range & Pasture Renovation
16. (210) Using Plant & Soil Analysis
17. (313) Odor Control
18. (416) Using Increased Resources: Range &
Pasture
19. (318) Feed Efficiency i Rations
20. (417) Range & Pasture Improvement
_!/ Panels: (1) Nonirrigated Crop Production
(2$ Irrigated Crop Production
(3) Feedlot Production
(4) Range and Pasture Management
Panel
1
1
2
5
4
3
6
7
10
11
13
8
12
14
9
16
15
17
18
20
19
& Ranking I/
3
1
2
4
7
9
10
11
5
3
6
14
8
12
16
13
17
15
19
18
20
4
1
2
3
6
7
5
4
8
11
9
10
12
13
16
14
15
1>
18
20
19
Sum of 2/
Ranking from
Panel 1, 3, 4
3
6
12
17
19
21
22
23
25
28
32
32
39
41
43
47
49
55
58
58
Panel &
Ranking
T
1
13.
2
1
15
5
9
8
4
10
6
3
7
5
14
12
18
17
16
11.
Sum of
Ranking from
Panel 1. 2. 3. 4
4
19
14
18
34
26
31
31
29
33
33
35
46
46
57
59
67
72
74
69
The sum of the individual panel's rankings yield a value suci that the lowest sum will be ranked first,
the next lowest sura will be ranked second and so on. Since Panel 1 used t different rating system to
arrive at a Workshop rank number for each trend (as explained in the Appendix), only Panels 1, 3, and 4's
rankings were used to determine a Workshop rank for each tre.^d. However, the rankings given td each
trend by Panel 2 are shown In the next column.
-------
Exhibit B-2. Summary of individual participant's ranking of twenty major agriculture trer.ds
Trend
No. Trends
(104) Runoff and Erosion Control (Nonirri gated)
(101) Conservation Tillage
(208) Improved Water Application
(204) Runoff and Erosion Control (Irrigated)
(119) Improvement of Seed and Plants
(120) Scouting and Integrated Controls
(121) Developing New Biological and Chemical
Pesticides
(319) Feedlot Design for Waste Management
^ (308) Feedlot Size
0 (317) Feedlot Residual Disposal
(211) Method of Nutrient Application
(406) Grazing Practices: Range & Pasture
(405) Stocking Rates: Range & Pasture
(220) Developing Integrated Controls
(401) Range & Pasture Renovation
(210) Using Plant & Soil Analysis
(313) Odor Control
(416) Using Increased Resources: Range & Pasture
(318) Feed Efficiency and Rations
(417) Range and Pasture Improvement
Work-
shop
Rank
i
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Individual Rankings From
10 Responses
1
5
1
3
5
2
4
6
12
9
14
8
10
13
4
15
7
17
16
18
11
2
1
3
5
4
2
7
6
10
14
11
&
13
15
9
17
12
16
19
20
18
3
1
2
3
4
5
6
8
10
12
11
9
15
13
7
19
17
13
20
14
16
4
1
3
4
2
14
5
6
9
19
8
7
11
!£,
13
16
10
12
17
18
20
fa
1
3
2
3
7
11
12
6
5
S
13
9
10
14
16
15
19
13
20
17
6
1
3
5
13
10
17
12
11
4
6
15
2
9
16
7
18
15
19
20
17
7
1
3
2
6
12
7
4
10
9
11
5
8
15
13
14
17
20
18
19
16
8
1
2
4
6
7
5
3
11
10
9
3
15
13
12
16
19
14
18
20
17
9
1
2
3
9
6
10
7
8
4
5
13
11
17
16
12
20
19
18
14
15
1C.
1
3
10
2
13
4
7
6
5
8
11
9
14
12
16
15
17
18
19
20
Sum of
Participant's
Rankings
14
25
41
54
78
75
71
93
91
91
97
113
134
105
148
150
167
181
182
167
Overall
Rank by
Individuals
1
2
3
4
7
6
5
10
3
9
11
13
14
12
15
16
18
19
20
17
-------
Exhibit B-3. Summary of individual participant's integration of second
five trends (#6-#10), as identified by his panel, into major twenty trends
Response
Number
1
2
3
4
5
6
7
Trend
No . Trend
(309) Geographic Concentration
None
None
(106) Wind Erosion Control
(110) Developing Nitrogen Fixation Sources
(173) Improving Pesticide Application
(106) Wind Erosion Control
(107) Improving Soil-Plant Analysis (could
combine with 210)
(108) Methods of Nutrient Applying (could
combine with 211)
(10G) Wind Erosion Control (could combine
with 104)
(106) Wind Erosion Control
(113) Improving Pesticide Application, Timing
Partic-
pant's
Panel
3
3
3
1
1
1
1
1
1
1
1
1
Rank in
Major
Twenty
15
__
—
12
14
14
18-20
15
11
16"
13
15
A-21
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/3-77-121
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Environmental Implications of Trends in Agriculture and
Silviculture Volume I: Trend Identification and
Evaluation
5. REPORT DATE
October 1977 issuing date
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Samuel 6. Unger
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
Development Planning and Research Associates, Inc.
Manhattan, KS 66502
IHB617
11. CONTRACT/GRANT NO.
68-03-2451
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Research Laboratory--Athens, GA
Office of Research and Development
U. S. Environmental Protection agency
College Station Road - Athens, GA 30605
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/01
15. SUPPLEMENTARY NOTES
Volume II: Environmental Effects of Trends
Current and emerging trends in U.S. agriculture and silviculture that will have
the most significant environmental implications in both the short term (1985) and the
long term (2010) are determined and assessed. Five major subsectors of agriculture and
silviculture were included in the analysis: (1) nonirrigated crop production, (2) ir-
rigated crop production, (3) feedlot production, (4) range and pasture management, (5)
silviculture and harvest management. Within each subsector, numerous trends and devel
opments were identified and defined by the Contractor. Thereafter,an evaluation work-
shop, comprised of subsector professionals from throughout the nation, evaluated, rate<
and rank-ordered the most significant environmentally related trends.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Agriculture
Silviculture
Environmental effects
Environmental quality management
02C
48D
680
91A
13. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (ThisReport)
UNCLASSIFIED
21. NO. OF PAGES
232
20. SECURITY CLASS (Thispage)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (9-73)
A-22 ft U. S. GOVERNMENT PRINTING OFFICE:J977-757-140/6579 Region No. 5-11
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