EPA 430/9-73-010
PROCESSES, PROCEDURES, AND METHODS
TO CONTROL POLLUTION RESULTING
FROM SILVICULTURAL ACTIVITIES
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Water Programs
Washington, D.C. 2O460
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FOREWORD
This report is issued in response to Section 304(e)(2)(A) of
Public Law 92-500. This Section provides:
The Administrator (Environmental Protection Agency),
after consultation with appropriate Federal and State
agencies and other interested persons, shall issue to
appropriate Federal agencies, the States, water
pollution control agencies, and agencies designated under
Section 208 of this Act, within one year after the
effective date of this subsection (and from time to time
thereafter) information including ... (2) processes,
procedures, and methods to control pollution resulting
from --
"(A) ... silvicultural activities, including runoff
from ... forest lands,"
This report prepared under contract by the firm Midwest
Research Institute, Kansas City, Missouri for the
Environmental Protection Agency, provides information of
a general nature regarding processes, procedures, and methods
for controlling pollution caused by sediment runoff from
logging roads, sxid trails, and other areas of disturbed soils
in forest areas; pesticides and fertilizers used in forest
regeneration activities; chemicals and other materials applied
for forest fire prevention; and temperature increases in small
streams exposed to solar radiation by logging of bordering
timber stands. It is intended to act as a state-of-the-art
document useful for the development of effective programs to
control nonpoint sources of pollution.
•
inistrator
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EPA 430/9-73-010
October 1973
PROCESSES, PROCEDURES, AND METHODS TO CONTROL
POLLUTION RESULTING FROM SILVICULTURAL ACTIVITIES
U.S. Environmental Protection Agency
Office of Air and Water Programs
Washington, D.C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price $1.25
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SUMMARY
The present status of "Processes, Procedures»and Methods to Control Pollu-
tion Resulting from Silvicultural Activities" has been analyzed in response
to the directive given to the Environmental Protection Agency by the Second
Session of the 92nd Congress in Section 304(2)(e) of Report No. 92-1465
titled "Federal Water Pollution Control Act Amendments of 1972," dated
September 28, 1973.
Nearly 203 million hectares (500 million acres) in the United States are
in forests managed primarily for the production of timber. The principal
water pollutants from this land area are eroded mineral soil sediments
transported in runoff; organic matter which is chiefly transmitted to the
water by runoff; pesticides; fertilizers; fire retardant chemicals; and
thermal pollution resulting from solar radiation. Of these pollutants,
sediment, including both its organic and inorganic (mineral soil) constit-
uents, is the greatest single cause of water quality degradation. Sedi-
ment additionally acts as a carrier of such pollutants as pesticides and
phosphorus. Control of erosion due to runoff is thus the most important
aspect of control of pollution from forests.
Pollution from forests is nonpoint in origin, and defies control or treat-
ment in the conventional sense. The treatment and control methodology is,
therefore, principally the forest management system--the combination of
practices involved in harvesting trees; log transport; reforestation; pro-
tection from fire, disease, insects and weed trees; and growth promotion.
The practices in current use require adaption to meet environmental goals
as well as to achieve other objectives which govern forest land use.
A well-managed forest with a good stand of trees is usually quite resis-
tant to erosion and also absorbs incident rainfall with little runoff.
Disturbed soil caused by tree harvesting, skidding logs to a landing area,
and constructing roads to haul logs from the forest, is highly erodible
and is a principal source of sediment pollution. Control of erosion,
therefore, requires strict attention to the period between harvest and re-
establishment of the forest. Required also is good management of an estab-
lished forest during its years of growth, so that a healthy forest is
present to assure minimum erosion.
Several alternate methods to harvest and transport trees are available.
These vary in potential to cause short-term pollution, in cost, in appli-
cability to regions or topography, and in long-term impact on the forest
and its potential to produce high quality water as well as timber. Log
transport options include helicopter log transport, which at present is
iii
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a highly specialized and costly method best suited to logging from very
steep and unstable slopes; skyline and balloon logging; tractor logging;
and rafting in sipecial situations. Harvest methods range from the contro-
versial "clearctt" method to selection and harvest of individual trees.
Logging roads are required for nearly all the harvesting and log transport
systems. The reads are a prime source of erosion; and careful planning,
engineering design, and maintenance of roads are necessary to control sedi-
ment pollution. Skid trails disturb the soil cover in harvested areas,
and methods which minimize the extent of this disturbance will reduce
erosion.
Reforestation methods range from hand planting, through man assisted
natural regeneration, to unassisted regeneration. The method of prefer-
ence from the standpoint of pollution control is the one which most quickly
results in reestablishment of a healthy forest. Unassisted regeneration
is to be avoided, as are practices which result in large acreages of mar-
ginal forest land.
Control of pollution from pesticides is a complex issue, one requiring
in-depth analyses of environmental questions. The specific control op-
tions available :o the silviculturist include the exercise of extreme
caution in the use and application of pesticides, including the avoidance
of streams in the application pattern; minimal or no use of prophylactic
control; avoidance of persistent or highly toxic pesticides; and use of
biological and cultural pest control methods.
Control of pollution from fertilizer and fire retardant chemicals consists
chiefly of adheresnce to a use plan which eliminates direct application to
surface waters, and which avoids excessive or unnecessary use.
Thermal pollution occurs when vegetation along water bodies is removed
and solar radiation penetrates to the water and increases its temperature.
Control consists of leaving protective stands of trees along stream banks.
One concludes that, while certain questions such as pesticides use remain
unresolved, the basic methods, processes, and procedures needed to control
nonpoint pollution from silviculture are available. One concludes further
that the key to pollution control from a forest dedicated to timber produc-
tion is intensive, well planned management rather than the laissez faire,
let nature take its course, approach.
Intensive management systems emphasizing timber production and integrat-
ing the efforts oE many technical and economic disciplines, are now in
limited use. The operating philosophies of such systems need to be broad-
ened to include pollution control, and pollution control management systems
iv
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thereby developed and implemented. Development of pollution control man-
agement systems for specific areas is the prerogative of local planners
and administrators, both public and private, with assistance on technical
issues and guidance on questions of policy from the regional and national
levels. Application and administration of pollution control on some
203 million hectares (500 million acres) now in commercial timber produc-
tion are the challenge.
v
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CONTENTS
Section
1.0 Introduction 1
2.0 Basic Silvicultural Practices in the United States . 5
3.0 The Nature of Pollution and Its Control in
Silviculture 23
4.0 Nonpoint Source Pollution Control Methods 29
5.0 Predictive Methodology for Nonpoint Source Pollution
Control 73
6.0 Criteria for Pollution Control Management Systems. . 79
7.0 Acknowledgments . 83
8.0 References 85
9.0 Glossary 91
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FIGURES
PAGE
1 COMMERCIAL FOREST LAND IN THE UNITED STATES 4
2 HIGH-LEAD LOGGING 12
3 SKYLINE LOGGING 13
4 BALLOON LOGGING 14
5 HELICOPIER LOGGING . 16
6 SOIL SURFACE CONDITION FOLLOWING TRACTOR, HIGH-LEAD,
SKYLINE AND BALLOON LOGGING IN THE WESTERN CASCADES
OF OREGON 33
7 EFFECT OF LOGGING PRACTICES ON SOIL COMPACTION 35
8 FOREST SERVICE REGIONS 39
9 A "LOGGER'S CHOICE" TRADITIONAL UNIMPROVED LOGGING ROAD
LOCATED IN A SOUTHEAST HARDWOOD FOREST 42
10 FOREST ROAD ENGINEERED ON SPECIFIED GRADE THROUGH A
STAND OF HARDWOOD IN THE SOUTHEAST PLANTED TO
GRASS 44
11 THE CONFLUENCE OF A STREAM FROM TWO FOREST WATERSHEDS
IN NORTH CAROLINA 45
12 TAKEN IN 1965 AFTER HARVEST AND WINDROWING WITH TRACK-
TYPE TRACTOR AND ROOTRAKE 51
13 FIVE-YEAR OLD DOUGLAS FIR TREES THAT WERE SEEDED DIRECTLY
ONTO A SLASH WINDROWED AREA, WITHOUT CONTROL-BURNING. . 52
14 A TYPICAL PERENNIAL STREAMCOURSE THAT SHOULD BE
CLASSIFIED AS SENSITIVE 57
15 A TYPICAL SENSITIVE INTERMITTENT STREAMCOURSE BEFORE IT
BECOMES DRY 57
Vlll
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FIGURES (CONCLUDED)
PAGE
16 RESISTANT STREAMCOURSES STABILIZED BY SOLID ROCK OR
HEAVY BOULDERS 58
17 A RESISTANT STREAMCOURSE 58
IX
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TABLES
No^ Page
1 Harvesting Procedures on National Forests in Eastern
and Western U.S., 1965 and 1970 6
2 Frequency of Forest Fires Necessary to Maintain Species 18
3 Effects of Log Transport System on Forest Soils .... 33
4 Erosion as a Function of Logging Systems 36
5 Sediment Losses Resulting from Silvicultural and Log
Transport Systems 37
6 A Comparison of Road Parameters on the H. J. Andrews
Experinental Forest in Western Oregon 41
7 Influence of Forest Cover on Control of Sediment Yield
by Erosion 47
8 Comparative Changes in Water Infiltration Rates in
Surfacs Soils Following 15 Years of Tree Growth ... 48
9 Effects of Burning on Sediment Production and of Tree
Planting on Sediment Control 49
10 Comparative Sediment Yield from Bare and Seeded Road
Cut on the H. J. Andrews Experimental Forest in
Western Oregon 55
11 State of Washington, Department of Natural Resources. . 60
12 Comparison of Nitrogen Fertilizer Applied on Foliage
and on Soil for Loblolly Pine 67
13 Actual Consumption of Fire Retardants in 1966 69
14 Protective-Strip Widths Required below Shoulders of
5-Year Old Logging Roads Built on Soil Derived from
Basalt, Having 30-Foot Cross-Drain Spacing, Zero
Initial Obstruction Distance, and 100% Fill Slope
Cover Density 75
x
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1.0 INTRODUCTION
The gross area of the 50 states is 930 million hectares (2.3 billion acres).
About one-fifth of this area, nearly 203 million hectares (500 million
acres), is commercial forest land—the principal thrust of this report.
The potential for generation of nonpoint source pollution from commercial
forest lands is substantial—so large a land mass is, in principle, capable
of discharging large quantities of pollutants into the nation's waterways.
The actual quantities of pollutants discharged to streams and other bodies
of water are determined in large part by the manner in which the forests
are managed and by efforts made to control and minimize pollution. The
silvicultural practices employed in forestry therefore include, or should
include, a basic forestry management system geared to both productivity
and pollution control, using special practices and strategies that have
been developed to deal with specific pollutional problems.
This report presents brief documentations of silvicultural practices, both
those now in use and those in stages of research and development well
enough advanced that they can be assessed for future use. A majority of
the report deals with the specific aspects of silvicultural activities
which relate to nonpoint source pollution control methods. The objective
of the study is to analyze existing and near future pollution control
methods in terms of technical and economic practicability and usefulness.
Pollution control in forestry does not consist of rectification and treat-
ment of polluted effluents immediately prior to discharge to an environ-
mental receptor, e.g., a stream or lake. Pollution from forest lands is
nonpoint in origin and thus defies treatment in the conventional sense.
The treatment and control methodology, therefore, is principally the forest
management system--a combination of practices and methods employed in the
harvest of trees; log transport; reforestation; forest protection (fire,
disease, insects, weed trees)', and growth promotion--adapted as necessary
to achieve environmental goals in union with realization of other goals,
which include as a minimum the production of lumber and other forest pro-
ducts achieved by harvest of trees.
The study team examined more than 900 literature references and reports
and elicited information and data, through personal contact, from authori-
ties in Washington, B.C., the South, the Northeast, the Northwest, and the
Southwest regions of the United States. The data and information which
serve as the information base for the study were derived chiefly from the
references cited in this report.
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The primary concern of the study is control of pollutants which originate
in commercial forest lands and degrade the quality of surface waters
(streams, rivers:, lakes, and oceans) and groundwater. The major identi-
fied sources of pollutants are mineral sediments; humLc matter present in
soils and in the; forest cover; tree debris (leaves, twigs, slash); pesti-
cides, including insecticides, fungicides, rodenticides, and silvicides;
fertilizers (nitrogen in various forms and phosphorus) ; and fire retardants,
which presently consist principally of the ingredients of fertilizers.
Thermal effects resulting from solar energy, specifically the effect of
forestry practices on stream temperatures, are also considered.
The national and state park systems managed for uses (recreation, wildlife
preservation, preservation of tree species) not including timber production
have not been included in the study. Similarly, the small private woodlands
have not specifically been evaluated; the pollution control methodology used
in commercial forests will, however, have general applicability to small
private holdings.
The study area embraces all the operations of a production cycle, from re-
generation through harvest and transport of logs and other timber raw prod-
ucts out of the forest proper to processing sites. For this report the
term silviculture is generally interpreted to include log transport pro-
cesses that occur from the stump to a hard-surfaced permanent: type road.
1.2 Water Quality in Relation to Silviculture
The U.S. Forest Service in the Department of Agriculture and the Bureau of
Land Management in the Department of the Interior were both directed by
congressional acts of I960 and 1964, respectively, to apply multiple use
concepts to lands under their respective jurisdiction.—' The term,
"multiple use", in the acts is defined broadly to include timber produc-
tion, livestock range management, watershed protection, outdoor recreation,
and fish and wildlife management.
Both agencies have been planning, classifying, and zoning lands under their
jurisdiction by "principal use" concepts under the following guidelines:
Environmental enhancement at the local level
Public demand for local use
Economic development on a local basis
Sustained yield of timber on an area basis
2
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By contrast, the national parks have been established on a no-use (no
silvicultural use) concept, "to conserve the scenery and the natural and
historic objects and the wildlife therein and to provide for the enjoyment
of the same in such manner and by such means as will leave them unimpaired
for the enjoyment of future generations."
In regard to American land area covered with commercial forests, the timber
supply is not equally distributed across the country. In general, the East
has a higher percentage of land area covered with commercial forests than
the West (Figure 1). Since rainfall is a major delineating factor in the
ecological development of forests, areas that have abundant rainfall tend
to have lush forest growth. These areas include New England, the
Appalachian Mountains, the Gulf Coast states, and the Pacific Northwest.
Because of the increasing demands for more timber products, both public and
private forests are anticipated to be managed more intensively to increase
production.-=/ The greatest present and potential production is concentrated
in the Pacific Northwest and in the South. The net result is expected to be
the use of more pesticides, fertilizers, and fire retardants, and the con-
struction of more logging roads. An increase in the potential for water
pollution from silvicultural activities is, therefore, a certainty.
Silvicultural activities may increase the probability of periodically low-
ering the quality of water from forested watersheds. On a per-acre basis,
however, forest lands are our best source of high quality water.—' On the
basis of comparisons with the output from agriculture and grazing lands,
water from forests is high in yield, of good quality, and low in sediment.
However, water quality can still be adversely affected by forest sediments,
especially those generated by the harvest of logs and in the ensuing period
of time in which the forest is (may be) deprived of protection from erosive
forces. While sediment, both inorganic and organic, is conceded to be the
principal forest land pollutant (and indeed is on a mass basis), pesticides,
fertilizers, and fire retardants employed on forest lands contribute pollu-
ting materials to the water supply. Studies of these latter pollutants
have been largely qualitative. They have demonstrated, for example, that
pesticides or fertilizers applied to forest lands may appear in adjoining
surface waters; how much of the applied materials reach the waterways is
ill-defined, though conceded to be a small percentage.
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2.0 BASIC SILVICULTURAL PRACTICES IN THE UNITED STATES
An evaluation of pollution control in silviculture must focus on the vari-
ous operations involved in the life cycle of a forest. These operations
are summarily discussed in this section.
2.1 Harvesting Methods
The tree harvesting operation is consummated in a period of time quite
short in relation to forest lifetimes, and it has both a high short-term
pollutional impact and a long-term impact spread out over the period of
time required for the forest to regenerate--to regain the degree of sta-
bility one considers to be normal and nominally nonpollutional. Procedures
employed at harvest time may irreversibly alter the character of the forest,
perhaps to the detriment of both the environment and the quality of the
forest in succeeding years. This is an important point because of the long-
term importance of our nation's forests as a natural resource.
3/
There are four principal harvesting methods— recognized and practiced in
the 37 major forest types in the United States. The harvesting methods
are: selection (single tree and group tree), shelterwood, seed-tree, and
clearcutting.
A particular harvesting method is chosen for a designated area based upon
judgments of professional foresters. Factors influencing judgment deci-
sions are aesthetics, forest-tree-regeneration potential of the species
to be favored,' erosion potential,' fire hazards* topography,' accessibility
and economics of markets ; insect and disease hazards* and requirements for
wildlife, taxes, and costs.
On the average, 25% to 35% of the area annually harvested in the U.S.
National Forests are harvested by the clearcutting method, but about 50%
of all wood removed has its origin in clearcutting (Table 1).
On an acreage basis in 1970 of the total of 605,000 hectares (1.50 million
acres) of national forests harvested, 218,000 hectares (540,000 acres) were
clearcut, 146,000 hectares (360,000 acres) underwent intermediate cut,
142,000 hectares (350,000 acres) were harvested by the shelterwood and
seed-tree methods, 69,000 hectares (170,000 acres) by shelterwood and
seed-tree prepatory cutting, 47,000 hectares (70,000 acres) by the se-
lection system, and 1,600 hectares (4,000 acres) from salvage operations.
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2.1.1 Selection: The selection system of silvicultural harvest is
adapted to the tolerant species that will reproduce satisfactorily under
severe competition for soil moisture, soil nutrients, and light. Such
species include redwood on the Pacific Coast in California; white fir and
incense cedar in California; ponderosa pine on the eastern slope of the
Sierra Nevada and Cascade mountains; Engelmann spruce, alpine fir, and
western larch in the Rocky Mountains; sugar maple and beech in the North-
ern hardwoods; and most of the white and red oaks in the central states.
The most tolerant forest tree species will reproduce satisfactorily follow-
ing the single tree selection method but less tolerant trees reproduce
better after the group selection method, where larger openings are made.
The selection system results in an all-age stand.
2.1.2 Shelterwood: As the name implies, the shelterwood system of tree
harvest removes all mature trees in a series of several harvests and there-
by leaves adequate overstory to shelter the site. The protective shelter
serves to improve aesthetics and to provide partial shade for reproduction
of forest species with a requirement for shade. Heavy-seeded species such
as the oaks usually reproduce well under this system.
The shelterwood system of harvest is well adapted to the Appalachian mixed
hardwood forest type, including species such as northern red oak, yellow
poplar, basswood, hickories, and white ash. Nearly all species reproduce
by sprouting as well as by seed. Eastern white pine is well adapted to
the shelterwood system, as is red pine in the Lake States.
A continuous shelterwood system of harvest results in forest stands that
are essentially even-aged.
2.1.3 Seed-tree: The seed-tree method is a timber harvest method that
clearcuts the area and leaves only sufficient trees to bear seed for
natural regeneration. The system is applicable to light seed that can be
borne by the wind. After a new forest is reseeded, the seed trees may be
harvested. The new forest is therefore even-aged.
The four southern pines (loblolly, longleaf, shortleaf, and slash) are the
principal species that are adapted to the seed-tree method of silvicultural
harvest.
2.1.4 Clearcutting: Clearcutting is the silvicultural system that in-
cludes the cutting of all trees from the logged area, and not just the
merchantable trees. The purpose is to clear the area in order to establish
a new, even-aged stand, usually of very valuable and fast-growing species
that will not reproduce satisfactorily under competition from other trees.
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The area clearcut may consist of patches, strips, or an entire watershed.
Regeneration may be obtained through established reproduction, natural
seeding prior to cutting, artificial seeding after cutting,, sprouts from
stumps (coppice), or planting.
Examples of clearcutting to achieve satisfactory reproduction of valuable
species include Douglas fir in the Pacific Northwest, western white pine
in northern Idaho, jack pine in the Lake States, loblolly pine in the South,
lodgepole pine in the Rocky Mountains, and black cherry in the Allegheny
Mountains.
Clearcutting is a standard practice used with several different logging
systems. With large volume, the practice is almost essential to permit
efficient use of high lead, skyline, balloon or helicopter systems.
Because of the great hazard of potential erosion, the advantages and dis-
advantages of clearcutting are given, as stated by Archie and Baumgartner-V
as follows:
Advantages
1. Creates good growing conditions 1.
for shade-intolerant tree species
(e.g., Douglas fir, noble fir).
2. Eliminates danger of wind damage 2.
or disease infection to residual
trees in the cutover area.
Disadvantages
Exposes seedlings to injury
from temperature extremes.
Increases risk of windthrow or
heat damage to trees bordering
the cutover area.
3. Improves forage for many game
animals (e.g., deer, elk) and
provides habitats for many animals
not present before logging.
4. Increases water yield during
low-flow periods.
5. Permits harvesting on slopes
too steep for ground equipment.
5.
May increase stream temperature,
debris jams, and sedimentation
(effect on fish population) and
reduce habitat of some animals
(e.g., woodpeckers, tree squirrels)
Elevates water table in swampy
areas.
May in some instances reduce pro-
tection against erosion and
landslides.
6. Minimizes road construction and
increases logging efficiency.
6. Is conspicuous and unattractive
during the harvest stage.
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Advantages
Disadvantages
9.
Facilitates administration in that
it limits tree marketing to defini-
tion of boundaries.
Facilitates slash disposal and site
preparation.
Usually maximizes the immediate
financial return.
10. Permits the use of genetically
improved tree planting stock.
9.
Magnifies need for proper har-
vest boundary layout.
Increases quantity of debris
(and fire hazard) to eliminate
at one time.
Eliminates merchantable timber
from the small landowners'
cutover area for many years.
10. Creates good growing conditions
for many unwanted brush species,
which compete with the young
seedlings.
2.2 Log Transport Engineering
All log transport methods require roads, and most methods use skid trails
to move logs to a yarding area from which they are usually moved by truck
over public and private roads to market. In some locations, logs may be
transported by water or by railroad. The principal log transport methods
for each logging operation include one or more of the following engineer-
ing systems: rafting (plus possible storage in water), tractors, high
lead, skyline cable, balloon, or helicopter.
2.2.1 Trails and roads: Soil sediments are a major pollutant from
forests, and logging roads and road construction are prime sources of
soil sediments. This statement is true for all commercial forests of the
United States. Roads are constructed primarily during, or preceding, the
logging period. They serve one or more of the three basic purposes during
harvest: provision of access by men and equipment to the logging area;
transport of logs out of the harvested acreage; and transport of logs from
yarding areas to sawmills, pulpmills, streams, or other destinations.
After harvest, the roads may be maintained as necessary for use in refores-
tation, fertilization, pest control, fire fighting, and public recreation.
Roads may be of low standard and highly susceptible to erosion, or they
may be well-built and relatively resistant to erosion. Even under ideal
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conditions, roads are a source of eroded soil during construction and
during the harvest period of heavy use.
The fraction of the forest acreage devoted to roads depends on several
factors, notably the harvest system, planned long-term use, and precon-
struction engineering design and planning. A well-planned and coordinated
road building-harvesting system can require much less road mileage than
results from an unplanned operation.
Road layout, especially in relation to topography, slope, and proximity to
watercourses, is quite important in pollution/sediment control.
Factors important in road construction are discussed further in Section 4.1
under Control of Sediment Sources.
2.2.2 Rafting and storage in water: Logging operations in the northwestern
U.S. can best be done during the dry summer months when damage to the water-
shed environment will be a minimum. Pulp mills, plywood mills, and saw
mills must operate year-round to be efficient. This means that many logs
must be stored before use. Storage on dry yards induces losses by exces-
sive cracking because of rapid drying. Where water is available, storing
logs in water has been an acceptable solution.2'
Log rafts and log storage in surface waters contribute directly to pollu-
tion of water. Bark dislodged from logs and chemicals leached from logs
are major local potential sources of pollution.
Guidelines for minimizing pollution from these two practices (where they
are judged to be both environmentally acceptable and economically expedi-
ent) are presented in Section 4.
2.2.3 Tractor: Tractor logging is the most popular system of moving logs
from where they are cut to the log yard. Forests on slopes of less than
about 30% are usually logged by tractors; on slopes of more than 30% and
on very fragile soils, the skyline, balloon, or helicopter system of en-
gineering transport is less injurious to the environment.
Tractor logging Ls substantially less expensive, in situations where trac-
tors can operate, than other log transport systems.
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2.2.4 High lead: The high lead system of logging consists of the use of
a mobile spar and yarder with mounted engine and winches, guy lines to
support the spar, and main line and haul back cables that carry log hooks.
Logs are dragged over the ground toward a loading yard (Figure 2). Only
the front end of the logs is lifted to clear obstacles or to reduce soil
disturbance. For short distances, a skilled operator can "fly" the entire
log over unstable areas such as a stream by increasing the speed.
2.2.5 Skyline cable: As early as 1915, skyline cable logging was tried
as a method adaptable to remote areas, steep slopes and unstable soils
where road building creates excessive erosion from landslides and exposed
cuts and fills. When operated skillfully, skyline cable logging does not
produce skid trails because the entire log is lifted in transport.
Herman—' reported that skyline cable logging required only one-tenth the
road construction needed for conventional logging methods such as tractor
and high-lead systems. The system of skyline cable logging is adapted for
clearcutting as well as for the selection method of harvesting.
The skyline system may consist of a single span (Figure 3) or a multiple
span, with intermediate supports attached to firmly anchored trees or
stumps.
Yarding of logs may be done near the bottom of the slope (but away from
streams) or near the top rim of the watershed divide. A very important
consideration is to install the cable system at such a height that logs
being transported will not disturb the protective surface of the soil.
Disturbance will then be confined to yarding areas where logs are loaded
on trucks.
2.2.6 Balloon logging: Gardner, Jacobsen, and HartsogZ/ reviewed the
practice of balloon logging in Idaho, especially as it has had a new
thrust because of its low pollution potential.
The system of balloon logging (Figure 4) is well adapted to steep slopes
(45 to 90%) and shallow and/or fragile soils, where only helicopter logging
or skyline logging may compete. The study suggests that the system is also
adapted to selective logging where the minimum harvest is about 70 cubic
meters per hectare (12,000 board feet per acre).
Balloon logging causes soil disturbance only at the yarding areas, from
which trucks haul the logs to the mill. Yarding areas can be as far as
914 meters (3,000 ft) apart but they must be downhill and therefore may
be a hazard to streams.
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00
60
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60
d
•1-1
60
60
O
d
O
O
03
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d
60
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At present, balloon logging is more expensive than most other logging
systems.
2.2.7 Helicopter: Because of the potential for minimizing pollution,
logging by large helicopter (Figure 5) is the apparent answer to the fond-
est dreams of concerned environmentalists. Reducing the dreams to engi-
Q /
neering, aesthetic, and economic realities was the objective of Binkley.—
Logging by helicopter was demonstrated to be feasible from the engineer's
judgment for any topography and for any forest type. Aesthetically, only
a heavy concentration of slash in the harvested areas detracts from their
appearance. However, costs of delivering logs to landings were higher
than for any transport system.
Logging by helicopter requires fewer access roads (and therefore probably
results in minimized sediment pollution of streams), costs more per thousand
board feet, and is the most versatile system of moving logs from where they
are cut to a yarding area for truck loading and hauling. It was suggested
by Binkley that helicopter logging probably should be used at present on
the most inaccessible areas with the most rugged terrain and high timber
value, and where aesthetics has high priority.
A weakness in the "no-road-take-it-out-by-helicopter-concept" is the need
to enter the forest on the ground to replant, thin trees, take out the com-
mercial thinning (poles), and for fire control. Normally the cost of con-
structing forest access roads has been borne by profits from harvesting the
mature timber and justified on the necessity for haul roads to remove the
logs. This silvicultural management problem has not yet been resolved in
the light of new aerial logging technology.
2.3 Reforestation
A majority of this country's forests are regenerated by natural processes.
The regenerative process differs substantially for different regions and
types of forests, and the harvesting method is usually geared to favor
propagation of desired tree species. Several types of reforestation methods
are discussed briefly in the following subsections.
2.3.1 Tree planting: Tree planting on clearcut areas and on eroded soils
in forested areas is an increasingly popular and effective practice. Since
1930, 14.7 million hectares (36.3 million acres) have been planted to trees.
The U.S. Forest Service, the state forest services, and the private forest
industries have led in this silvicultural activity. Further, the U.S. Soil
Conservation Service has made a major contribution to the science and prac-
tice of tree planting.
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Figure 5 - Helicopter Logging
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Scientific guidance from the above-named agencies is available to enable
the establishment of productive forests in marginal areas as well as areas
suitable for high yield timber production.
2.3.2 Natural regeneration: Natural regeneration to reestablish productive
stands of preferred tree species is best obtained when the forest practice
is set up to provide favorable conditions for natural seeding or sprouting
and growth of the desired species. The method of harvest is an important
factor in establishing the required conditions. The seed-tree method is
suitable for propagation of selected southern pines species. The shelter-
wood system of harvest is well adapted to regeneration of Appalachian mixed
hardwoods. The selection system is adapted to propagation of species such
as the redwood in the Pacific Southwest and Engelmann spruce and alpine fir
in the Rocky Mountains. The clearcut harvest method is suitable for estab-
lishment of uniform stands (even-aged) of intolerant species that'do not re-
produce readily under competition from other trees; Douglas fir in the
Pacific Northwest, and western white pine in northern Idaho are among the
classic species which achieve satisfactory reproduction from clearcut areas.
2.3.3 Influence of fire on reforestation: Historically, forest wildfires
in nature have played an important role in natural regeneration and main-
u /
tenance of some of our preferred tree species. Hendrickson— has stated that
from studies of tree rings, the frequency of fires in various types of for-
ests are shown in Table 2. Silvicultural theory interprets these and other
data as evidence that fires have an important and necessary silvicidal
function in maintaining stands of specific forest species. Periodic fire
to reduce competition from competing vegetation and to expose mineral soil
is considered to be necessary for maintenance of the Douglas fir forests
west of the Cascade Mountains and the pine forests of the south.
As the art of silviculture has advanced, the use of fire has been benefi-
cially controlled, and in recent years use of prescribed fires in silvicul-
tural activities is a scientifically accepted practice. Prescribed burning
is extensively employed to reduce potential wildfires by systematically
preventing the surface buildup of fuel resulting from slash and other
forest debris. Traditionally it has been an accepted silvicultural practice
to remove unwanted vegetation by a process of controlled burning to permit
direct mineral soil contact of seed of intolerant and most valuable tree
species.
With the new emphasis on control of pollution in our nation's forests,
there is a search for ways to reduce or eliminate the use of fire as a
necessary tool to silvicultural management. Up to the present time, our
known technology has not been able to encourage a no-burn strategy. There
is now evidence, however, that on specified forest locations, burning can
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be eliminated as a requirement for reforestation of some of the intolerant
tree species.
TABLE 2
FREQUENCY OF FOREST FIRES NECESSARY TO MAINTAIN SPECIES
Tree Species Requiring
Fire to Maintain Themselves Frequency of Fires
in a Forest (years)
Slash Pine, Long Leaf Pine 3-18
Ponderosa Pine, Pitch Pine 12-25
Douglas Fir 25-50
Quaking Aspen 50-100
Lodgepole Pine, Jack Pine 100-300
Source: Hendrickson, William H., "Perspective on Fire and Ecosystems in
the U.S.," in, Fire in the Environment—Symposium Proceedings,
Denver, Colorado, 1-5 May 1972, 151 pages, pp. 29-33.
As an alternative to controlled burning, the U.S. Navy has successfully
established good stands of Douglas fir in the Pacific Northwest without
the use of fire in the period from 1966 to 1972.iy./ The slash was contour
windrowed with track-type tractors, followed by rootrakes. Tree seed was
then sown directly on the bare mineral soil exposed between windrows. In
time the piled vegetation rotted down. This highly successful new system
for reforestation of an intolerant tree species should have wide applica-
tion in the major forests of the Northwest and South. The system has the
potential, where topography permits, to significantly minimize pollutant
emissions from forests. Research and more field studies are required be-
fore it can be widely adopted, however.
2.4 Intermediate Practices
Certain practices are employed primarily for the benefit of the growing
forest. Pest control, fertilization, fire retardation, thinning and
silvicide chemicals belong in this category. Prescribed burning may also
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be an intermediate practice, specifically when controlled burning is used
to dispose of forest debris to reduce the dangers of wildfires and for
silvicidal purposes, e.g., to destroy small weed trees in a large estab-
lished forest. Prescribed burning has been treated in Section 2.3.3.
2.4.1 Pest control: Chemical pesticides are used in forestry for control
of insects, weeds and weed trees, plant diseases and rodents. The U.S.
Department of Agriculture reports that insects and diseases are responsible
for losses in the U.S. that far exceed losses from forest fires. Current
annual losses from these causes distributed about equally between mortality
and growth loss are estimated to be about 135.8 million cubic meters
(4.8 billion cubic feet). If no pest control activities were carried out,
an additional loss of 28.3 million cubic meters (1.0 billion cubic feet)
is predicted. Insecticide and fungicide use is credited with about two-
thirds, 19 million cubic meters (0.67 billion cubic feet), of this savings.
In 1969, 1,251,367 trees were treated for insect control, and an additional
13,535 hectares (33,839 acres) of trees were sprayed to control insects.
The U.S. Forest Service has made a concerted effort to move away from the
use of persistent insecticides toward cultural, biological and integrated
control methods and to nonpersistent specific chemicals. From 1965 to 1970,
the total use of pesticides in Forest Service programs decreased from
500,000 kg (1,353,000 Ib) to about 115,000 kg (310,000 Ib).
The Forest Service sprayed 107,500 hectares (268,666 acres) with herbicides
in 1969. Only a small portion (< 0.1%) of forest lands is treated with
herbicides each year to control undesirable tree species and reduce growth
of combustible plant materials.
Current public concern related to the pollution hazards of pesticide use
has brought about the consideration of new management alternatives in the
control of forest insects. Rather than use spray in some areas, dying trees
are salvaged; clearcutting has been practiced to harvest the trees and
realize some economic benefit. Increasingly, a no-spray policy is being
carried out with the hope that natural controls will keep insect damage to
some acceptable level of damage. Research is in progress to find nonchemi-
cal means of biological control to assist in policy of let-nature-take-her-
course. Hardly anyone will advocate a policy of continuous prophylactic
spraying because the practice contributes to overhead cost and must con-
tinue indefinitely. The practice of spraying insect infestations in rela-
tively small areas before they can spread to epidemic proportions appears
to be a sound management practice.
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Research investigations are being carried on to compound effective chemicals
that will kill unwanted insects, then break down into chemicals that are
harmless in a forest ecosystem. It will take time to develop the research
finesse needed to adapt to requirements for environmental compatibility.
Owners of small timber holdings generally do not spray because of cost and
intensive management requirements. Little information is available on
pesticide use by the private forest industry with large acreages of timber.
Unlike public agencies, the private industry is not required by law to re-
port use of chemicals to spray insects.
2.4.2 Fertilization: Recent research has established that selected tree
species respond well to the application of chemical plant nutrients, es-
pecially to nitrogen. A great deal of practical judgment has been involved
in the decision to use fertilizer; however, very little actual research in-
formation is available at this time. Aside from the technical question of
application rate and most effective distribution procedures, there are the
two overriding questions: (1) cost effectiveness of fertilization in long
time span for growing trees, and (2) the risk of contributing nutrients to
surface waters in the area, and increasing the potential for eutrophication.
In the Pacific Northwest, on a commercial basis, forest fertilization with
nitrogen started in 1965 and reached a level of 47,500 hectares (118,750
acres) in 1970. This practice is anticipated to be 100,000 hectares (250,000
acres) per year during 1975-1980.
Forest fertilization in the South started in 1963 on a commercial basis;
and in 1971, it is estimated that 44,440 hectares (110,000 acres) had been
fertilized.
More extensive reporting is needed to document the use of fertilizers in
forestry.
2.4.3 Fire retardation: The use of chemicals to control or manage fire
is an essential practice in silviculture.
The use of all types of fire retardants was reported by Hartongil/ in 1966
to have been 40.5 million liters (10,708,160 gaL). At that time the 1967
use estimate of consumption was 60 million liters (16 million gal.), and
the estimate for the year 1971 was in the range of 37.8 to 56.8 million
liters (10 to 15 million gal.).
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Historically, fire retardant chemicals were primarily bentonites and
borates, which are still used to a limited extent. However, the most
effective and widely used chemicals to fight or control forest fire are
made by industry in two proprietary formulations of ammonium sulfate
and diammonium phosphate. These compounds contain the ingredients of
plant fertilizers, N and P, and enhance the growth of trees. Their re-
lease into surface waters can yield toxic concentrations of ammonia and
promote eutrophication.—'
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3.0 THE NATURE OF POLLUTION AND ITS CONTROL IN SILVICULTURE
As stated in preceding sections of this document, forest lands, by their
basic characteristics and their size, are potentially contributors of sub-
stantial quantities of pollutants to the aquatic environment. An assess-
ment of the actual contribution of forest land to water quality, or the
lack thereof, is beyond the scope of the present study. One can hardly
evaluate control of pollution without first having established an under-
standing of the basic nature of pollutional problems in silviculture, how-
ever. In this section, the general nature of pollution from forests will
be discussed, and certain basic issues will be defined.
3.1 The Basic Approach to Pollution Control
In Section 1.0 the forest management system was identified as the focus of
controls for nonpoint pollution. Silvicultural pollution is, therefore,
controlled by:(1) the exercise of informed judgment in introduction of po-
tential pollutants (e.g., pesticides, fertilizers) into the forest; per-
haps most importantly, (2) by systematic use of methods and management
practices which minimize the generation of pollutants from the forest en-
vironment; and lastly (3) by containment of pollutants within the forest
proper. In other words: (a) introduce potential environmental contaminants
into the forest with impunity; (b) manage the forest so that it is a minimum
creator of pollutants; and (c) see that pollutants picked up by pollutant
transport vehicles are kept within the bounds of the forest ecosystem.
The above precepts must be tempered with the boundaries of technical and
economic practicability. It is necessary, furthermore, to evaluate over-
all control strategies in terms of four related objectives, which are as
follows:
1. Timber production in quantity and quality necessary to meet consumer
demand.
2. Water production--forests are the most important natural system for
providing high quality inland water.
3. Protection of the quality of water emanating from forests for the use
of man.
4. Direct preservation of the habitat for woodland aquatic life, and in-
direct preservation of the habitat for downstream aquatic life.
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This study has been addressed primarily to Objectives 3 and 4. Timber pro-
duction and water production are broad objectives which encompass issues,
such as land use and societal priorities, which are recognized as important
but are outside tne scope of the present study.
3.2 Major Pollutants From Silviculture
Water pollutants generated by forest lands are of essentially the same char-
acter and nature as pollutants generated by agriculture. Mineral soil
matter (soil sediments) is transported to surface waters by the erosive
action of runoff from rainfall and snowmelt. Organic matter of vegetative
and animal origin is likewise transported to surface waters by runoff. The
organic matter ranges from green vegetative refuse through well-decomposed
humic matter. The organic matter sometimes has a high nuisance value
(floating debris); sometimes physically interferes with normal aquatic ecol-
ogy (bark deposited in spawning beds); and nearly always becomes involved
in biochemical processes which are nature's way of degrading organic matter
and which can markedly alter chemical/biological balances in an aqueous
ecosystem—an oft-mentioned imbalance is the depletion of oxygen in water
to a point of inadequacy for fish. Fertilizers and fire retardants contrib-
ute nutrient elements to the forest environment. These elements, primarily
nitrogen and phosphorus, can be transported overland to surface waters in
runoff and to both surface and groundwaters by infiltration through ground-
cover and subsurface soils and mineral formations. Nitrogen is a "water
soluble" element in both the reduced (ammonia) and oxidized (nitrite and
nitrate) forms and is much more susceptible to transport in runoff water
and infiltrating water than is phosphorus. Ammonia is toxic to fish at a
concentration lesjs than 1 ppm. The nitrate and nitrite ions are toxic, es-
pecially the latt«r. Phosphorus is chiefly noted for its role in the eutro-
phication process.. Both nitrogen and phosphorus are essential elements for
plants, animals, and man—they are pollutants only when present in too high
a concentration. Fertilizer and fire retardant uses are polluting practices
only to the extent: that they create a nutrient imbalance in aqueous eco-
systems or generate concentrations in water directly toxic to aquatic and
animal life.
Thermal pollution from solar energy is a possible result of silvicultural
activities. Strictly speaking, both negative and positive deviations from
"normal" temperatures in surface waters are pollutional. However, thermal
pollution popularly consists of an elevation of temperature above an accepted
norm. The source of thermal pollution from forests is the presence or ab-
sence of protection from solar energy. Trees along streams protect the water
bodies from the direct rays of the sun, and water temperatures may be sub-
stantially higher when these trees are cut.
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Finally, pesticides used in silviculture are potential water pollutants.
Insecticides, fungicides, herbicides (silvicides) and rodenticides used
to control silvicultural pests may be deposited directly in surface water
courses by careless application or be transported thereto in surface or
subsurface runoff.
Pesticides differ from pollutants enumerated above in that the great major-
ity of pesticides used in silviculture are not materials native to the
forest environment. Pesticides furthermore are toxic, by design, to some
part of the environment in the accepted mode of use. Control of pesticide
pollution is, therefore, a more complex issue than is control of other
forest pollutants. Analyses of the question require knowledge of persis-
tence of the pesticide at the point of use, of rates of degradation, of
modes of degradation and of biological and chemical metabolites, of mech-
anisms of transport through the environment to nontarget species in the
event that pesticides do not degrade easily and completely to nontoxic end
products, and knowledge of toxicity to nontarget species.
Pesticide use in silviculture is inextricably related to ecosystem stability
in the forest system. Control of pesticide pollution in the aquatic environ-
ment is thus intimately related to controls imposed for protection of the
forest ecosystem.
In the present state of silviculture, soil sediment is easily the most im-
portant pollutant. Sediments are generated in quantities and concentra-
tions far in excess of pollutant loadings from fertilizers, pesticides, and
fire retardants. Sediments degrade water quality physically and biochemi-
cally and are an economic burden in urban water uses. It is also of prime
importance that sediments are carriers of pesticide residues and nutrient
elements. Effective control of sediment discharge will constitute a high
level of effective control as well of pesticide and nutrient emissions from
forest lands.
3.3 Principal Sources of Pollution
An established, well managed forest can be remarkably resistant to emission
of pollutants to the aquatic environment. Incident rainfall is deprived of
most of its erosive force by the tree cover, and rates of infiltration
through ground cover and into subsurface soils are often high enough that
intense rainfall can be accommodated without runoff and the accompanying
carryoff of silt by erosion. Such a forest has the attributes popularly
decreed by the public to be necessary and desirable as well as technically
and economically sound. Many forests do indeed possess such attributes,
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and are at the same time, useful productive entities. Productivity can
be maintained over the long term only with assistance (interference) from
man, which necessarily includes harvest of trees. A silvicultural cycle
thus includes a relatively long period of growth which can be essentially
free of pollutional output, and a relatively short period of harvest: and
reforestation, which can be a time of high pollutional output. In some
silvicultural systems the trees are all-age and are harvested as they
mature. Man's encroachment on the forest is in this case every few
decades, and the pollutional output is likely to be relatively constant
but at a low level.
Insults to the forest come from nature as well as from man. Disease, in-
sects, windstorms, drought, and fire can devastate a forest and degrade it
to a polluting condition. Silviculture is concerned with both the preven-
tion of such evencs and with restoration to a state of health and
productivity.
The principal sources of pollution from silviculture thus are disturbances
which are natural in origin or are caused by man in the activities of
harvesting, reforestation, growth promotion, disease prevention, fire fight-
ing and fire prevention, and rectification of the effects of natural
occurrences.
Specific sources of pollutants are indicated in the following subsections.
3.3.1 Sources of sediments: Roads are the principal source of mineral sedi-
ments as a result of erosion by water. Roads ordinarily are constructed
just prior to the logging operation. They provide access for equipment and
serve as routes for transport of logs out of the forest.
Skid trails, the disturbances created by hauling logs from the freshly cut
area to yarding areas or roads, are a significant source of sediments.
Yarding and staging areas contain exposed, compacted mineral soil with
little capacity to absorb rainfall and which, therefore, are erodible
sources of runoff which initiate erosion in less disturbed areas.
The entire harvested area is susceptible to erosion until the scars of har-
vesting and logging are healed by a combination of engineering design prac-
tices and reestablishment of vegetative (grass, shrub, tree) cover suffi-
cient to protect the soil surface and prevent erosion.
Burned-over areas may be deprived of the. protection needed to forestall
erosion.
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Landslides generate a mass of displaced soil and organic sediments,
which may be deposited in streams, and leave exposed, unstable and highly
erodible surfaces. Landslides are most probable in areas which have been
disturbed, e.g., by road construction or fire.
Streambanks vary in erodibility. Similarly, major drainage paths are more
exposed and prone to erosion than is the majority of the forest floor.
Logging patterns can influence the water hydrology of an area and can in-
crease the peak runoff causing streambank erosion.
Forest debris (leaves, bark, twigs, slash) is a significant source of or-
ganic sediment and waterborne wood litter. Waterways used for transport
and storage of logs become contaminated to a degree by bark knocked off the
logs.
3.3.2 Sources of nutrient elements: Nitrogen, phosphorus, and other min-
eral elements are present naturally in growing or decaying vegetation and
in mineral soils. One or more may be added to the forest environment by
fertilization (usually only nitrogen) and in fire retardants (nitrogen and
phosphorus). Wastes from wild animals are also sources of these elements.
Aerial application of fertilizers is increasingly practiced and drift or
error can directly contaminate streams.
3.3.3 Sources of pesticides: Pesticides are applied by man, often by
aerial spray, occasionally from the ground. Aerial application can con-
taminate streams directly, from drift or as a result of error.
3.3.4 Sources of thermal pollution resulting from solar energy: Thermal
pollution results from removal of shade cover from stream banks and the
solar heating of the water of streams.
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4.0 NONPOINT SOURCE POLLUTION CONTROL METHODS
Methods to control pollution resulting from silvicultural activities must
include ways to prevent polluting effects from sediments, pesticides,
chemical fertilizers, fire retardant chemicals and thermal pollution
caused by solar energy.
Control of sediment from soil erosion can be most effective when all
factors in the silviculture and harvest system are systematically planned
with soil and water management to prevent soil erosion as a principal
objective. The selection of a harvest system is basic to sediment con-
trol and must be responsive to a range of conditions on any particular
logging location. Selective logging methods are likely to generate low
yields of sediment at frequent intervals. In contrast, the practice of
clearcutting all the trees from an area at one time can result in sedi-
ment yields that are confined to one continuous period of perhaps 2
to 5 yr, followed by a long period of time when the forest floor is undis-
turbed, giving maximum control of erosion and minimal outputs of sediment
pollution.
During the harvesting period sediment can also be controlled by the
proper selection of a logging system. To harvest a given location there
is usually a choice between two or more major systems, these being—
tractor; high lead; skyline; balloon; and helicopter, or variations and
combinations of these systems which vary substantially in physical impact
on the forest and in potential for erosion and sediment production.
These harvest systems also vary substantially in cost and in adaptability
to forest types and different terrains.
In addition, research has clearly documented that logging roads and
trails over which logs are dragged are major sources of erosion and
sediment. However, pollution from these sources can be substantially
prevented or controlled by careful planning of the layout, construction
and use of roads, including the after-harvest use.
Seeded grasses, legumes or other vegetative cover can effectively
stabilize soils on such locations as logging-road banks, unused and
abandoned road surfaces, fire lanes, and open harvested areas. Grass
cover is usually temporary, but may be a permanent part of the forest
management system.
In some locations vegetative cover alone cannot effect sediment control,
and engineering structures are required to manage water to prevent
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erosion or trap sediment in the overall forest management control
system.
There is evidence that controlled and well managed grazing of domestic
animals can benefit the forest and help minimize erosion. On the
other hand, improper or excessive grazing will compact soil, remove
cover, cause downhill trails and promote erosion.
A major factor in any coordinated system to control sediment is effec-
tive reforestation, which is considered to be the most important remedial
control.
Stands of trees should be propagated in harvested areas, mismanaged areas,
and areas devastated by disease, fire and other natural causes. Methods
used to propagate new stands of trees range from essentially unmanaged
natural regeneration to hand planting of genetically improved nursery
stock.
Pesticide pollution control is a current and continuing management
problem. Some of the approaches employed to effect better control
follow.
Rigorous management of aerial application to protect nontarget: areas,
including bodies of water, and to maximize effectiveness on target
species.
Application from the ground on specific targets, including direct
injection into infected or weed trees.
Scheduling of applications for maximized effectiveness and minimized
dispersal to nontarget areas.
Avoidance of highly persistent, bioaccumulated pesticides.
Minimun use of prophylactic applications.
Increased uise of cultural and mechanical methods to control pests and
weeds.
No spray, with complete dependence on natural prey-predator relation-
ships in combination with cultural and mechanical control.
The preferred use of pesticides for insect and disease control is one of
the more undecided issues at this time in silvicultural management.
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Fertilizers can be safely used in silvicultural management. Control
measures to prevent water pollution from the application of fertilizers
in a forest consist of using the amounts and kinds based upon a soil
test, and in careful application procedures to avoid streams.
Control of water pollution from the use of fire retardants includes both
the precision application of material and location of drops in relation
to streams or lakes. Unless these chemicals are carefully used, they
represent an almost certain source of water pollution.
In recent years the warming of streams from solar energy has been widely
discussed. Control measures to prevent such thermal pollution will
require policy planning followed by planned retention of riparian vege-
tation needed to achieve thermal pollution goals.
4.1 Control of Sediment Sources
Inorganic and organic sediment is a major contribution to deterioration
of water quality from commercially timbered watersheds. It is generated
primarily during specific functions in the overall silvicultural manage-
ment activities. Sediment may or may not be directly related to man's
management procedures. Substantial research has been conducted on this
subject by the collective forest industry. In addition, a great deal of
sediment control technology used in highway construction and in agri-
culture is being effectively adapted to sediment control from forest
roads, logging procedures and the watershed area at large.
Sediment control technology is sufficiently advanced and mature enough
to provide a scientific and engineering procedural base for extensive
implementation on a secondary watershed basis, and to permit the for-
malizing of plans to effectively protect the integrity of surface waters
discharged from forested watersheds. Such plans and procedures should,
however, be tested in the field to develop a realistic picture of man's
ability to control sediment pollution.
Control of sediment involves control of three factors: (1) the quantity
and intensity of runoff; (2) the susceptibility of ground cover and
mineral soils to erosion; and (3) the quantity and placement of certain
types of forest debris. Control methods are directed generally at the
establishment and maintenance of vegetative cover to reduce the erosive
impact of rainfall, to bind mineral soils in a root network and to fur-
nish an organic soil cover permeable to moisture and with high moisture
retention capacity. The vegetative cover, in addition, enhances the
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permeability of mineral soils to water. Rainfall, therefore, infiltrates
readily, and runoff is minimized. When disturbance of forest cover and
exposure of mineral soils is necessitated, to build logging roads for
example, engineering and vegetative stabilization procedures are called
for, as well as design of the disturbance (such as a road) to be minimum
both in size and in susceptibility to erosion.
4.1.1 Sediment control by proper design of the harvest system: Erosion
and sediment generation can be markedly affected by proper selection and
design of harvesting and logging systems, and by construction and use of
accessory roads and skid trails.
Surface soil erosion is described by Swanston and DyrnessJLi/ as a two-
stage process--detachment and transport. Detachment: is accomplished
when the raindrop with high kinetic energy strikes bare soil of medium
to fine texture and turns it into flowing mud. As long as the 2.5 to
7.5 cm (1 to 3 in.) layer of surface organic matter remains intact,
there is seldom any detachment and subsequent transport of sediments.
In fact, there is seldom any surface runoff water.
In addition to bare soils, compaction of soils is also important in
inducing surface soil erosion. Compacted soils have lower rates and
lower capacities for infiltration of water. When rains and water from
melting snows cannot move by infiltration into the soil as fast as they
must be removed, surface runoff and a soil erosion hazard exists.
Logs skidded over the surface of the soil can cause soil compaction that
may be evident for 5 yr or more. When skidding is up or down the
slope, the results are bare soil that is easily detached by the falling
raindrop, a compacted soil beneath with a low rate of infiltration, and
a channel through which soil sediments are transported rapidly to the
streams.
Logging methods that result in a large percentage of bare soil and of
compacted soil are methods that must be avoided in this environmental
age of the 1970's.
Dyrness.M/ studied the relative soil disturbance incident to logging
transport by tractor, high lead, skyline, and balloon systems. The
data in Figure 6 and Table 3 show that balloon logging results in a
larger percentage of undisturbed area and a smaller percentage of the
logged area w:lth compacted soils. Sediment washed from a logged area
and into a stream is directly proportional to soil disturbance and
soil compaction.
32
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Figure 6 - Soil Surface Condition Following Tractor,
High-Lead, Skyline and Balloon Logging
in the Western Cascades of Oregon
TABLE 3
EFFECTS OF LOG TRANSPORT SYSTEM ON FOREST SOILS
Log Transport
System
Percentage of
Logged Watershed
with Bare Soil
Balloon
Skyline
High lead
Tractor
6.0
12.1
14.8
35.1
Percentage of
Logged
Watershed with
Compacted Soil
1.7
3.4
9.1
26.4
33
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Of great significance to potential soil sediment loss from logged areas
is the difference in the percentage of soil surface area compacted by
two logging S3rstems. Two hundred separate bulk density measurements were made
to a depth of 5 cm (2 in.) on soils before and after logging. The
logging systems compared were high lead and tractor. H/
Slopes on the areas logged by the high-lead system during the wet season
in the winter of 1963 varied from 20-80% and averaged about 55%. This
was in contrast to the area with 10-40% slopes, which averaged about 25%,
that was logged by tractor during the dry season during the fall of 1963.
From Figure 7 it can be observed that following tractor logging, soil
compaction increased an average of 48.2% on 26.9% of the area logged.
This is in comparison with an increase in soil compaction of 33.7% on
only 9.1% of the area logged by the high- lead system.
The potential for sediment generation, from high erodible soils, was
demonstrated in a study in central Idaho. 12.' Monitored watersheds not
logged, and where no logging roads were constructed, lost an average of
0.025 metric tons/sq km (140 Ib/sq mi.) of soil sediment per day over the
6-yr period under study. Both jammer logging and skyline logging of
similar watersheds and the roads built to transport the logs resulted in
an increase oi: soil sediment loss by a factor of 750.
Rice, Rothacher, and MegahaniZ' have summarized from published and unpub-
lished data the percentage of soil in logged areas made bare by various
logging systeris in Washington, Oregon, Idaho, and California. The
assumption can be made that when other ecological factors are similar,
the more bare soil exposed the greater the soil sediment that moves to
pollute streams.
If this assumption is correct, the control of soil sediment can be
achieved by the selection of the logging system that exposes the least
mineral soil. The greatest percentage of soil bared resulted (in de-
creasing order) from: jammer (group selection), tractor (clearcutting) ,
and cable (selection).
compared soil disturbance during logging and soil erosion after
logging, using the logging systems: cable skidding, tractor skidding on
bare soil, tractor skidding on snow, and helicopter.
The percentage of the logged area observed to be eroded following logging
plus two summer rainstorms was:
34
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35
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TABLE 4
EROSION AS A FUNCTION OF LOGGING SYSTEMS
Percentage of the
Logged Area Observed
Logging System to be Eroded
Helicopter 3
Tractor skidding on snow 13
Tractor skidding on bare soil 31
Cable skidding 41
Assuming that these four systems are applicable to a watershed to be
logged, and fiat the costs were comparable, the order of preference
would be from first to last: helicopter, tractor skidding on snow,
tractor skidding on bare soil, and cable skidding.
Dyrness-i-v compared the relative soil disturbance hazard of four logging
transport systems: tractor, high lead, skyline, and balloon. Using
only one of his categories, soil compaction, as an indirect measure of
erosion potential, the systems responsible for the greatest soil compac-
tion, in order from highest to lowest, were: tractor, high lead, skyline,
and balloon.
In the selection of a log transport system with the least sediment pollu-
tion hazard under the conditions monitored, the priorities would be:
balloon, skyline, high lead, and tractor.
Dyrness—' analyzed the cause of 47 mass soil movements in the winter of
1964-1965 on the H. J. Andrews Experimental Forest in western Oregon.
About 72% (34) of the mass movements were associated with road construc-
tion and 17% (8) of these were in areas that had been logged. Only 11%
(5) of the mass soil movements occurred in the areas undisturbed by man;
the remaining 42 were related in some way to man and machines. Soils
developed from pyroclastic rocks (volcanic rock fragments such as tuff
or breccia) occupy only 37% of the total area studied, but were respon-
sible for 94% (44) of the mass soil failures. Soils on a southern or
southwestern aspect were more stable than those on any other aspect,
probably because they tend to be shallower and drier. Slopes steeper
than 45% were: responsible for 83% (39) of all mass soil failures.
36
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The Dyrness study confirms the generally expressed opinion that logging
roads are the principal source of soil sediment.
On deep soils in western Oregon, with slopes up to 1107o, sediment yields
were measured by Fredriksen-=i-' for 9 yr following clearcut logging by
the skyline system (no roads and no skid trails versus patch-cut logging
on 25% of the total forested area by the high-lead system, 2.65 km (1.65
miles) of roads). An uncut forest nearby was used for comparison.
Although 100% of the clearcut area was logged as against only 25%, of the
total area that was patch-logged, the clearcut area yielded less than 4%
as much soil sediment. The reason was because there were no roads in the
clearcut area, but 2.65 km (1.65 miles) of roads in the patch-cut area
(Table 5).
TABLE 5
SEDIMENT LOSSES RESULTING FROM SILVICULTURAL
AND LOG TRANSPORT SYSTEMS-^/
Logging Roads
Silvicultural
Harvesting
System
Control
(no harvest)
Clearcutting
Clearcutting
in patches
Logging
Transport
System
0
0
Km
(Miles)
(0)
% of
Area
Harvested
0
Skyline
High lead
0 (0)
2.65 (1.65)
100
25
Sediment Lost
in 9 Yr
Metric Ton/Sq Km/Yr
(Tons/Sq Mi/Yr)
32.5 (93)
107 (307)
2,794 (7,982)
a/ Fredriksen, R. L., "Erosion and Sedimentation Following Road Con-
struction and Timber Harvest on Unstable Soils and Three Small
Western Oregon Watersheds," USDA Forest Service Research Paper
PNW-104, 15 pages (1970).
A comparison of the soil sediment yields was as follows: control,
32.5 metric tons/sq km/yr (93 tons/sq mi/yr) of soil sediment; clear-
cutting (no roads), 107 metric tons (307 tons); and Clearcutting in
patches, 2.65 km of road (1.65 miles of road), 2,794 metric tons/sq km/yr
(7,982 tons/sq mi/yr).
37
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The roads, from which the sediment came, met the U.S. Forest Service stan-
dards for all-weather roads with culverts, cross drains, base rock, and
crushed rock surface. The construction of the 2.65 km (1.65 miles) of
roads exposed (>.3 hectares (15.6 acres) of bare soil in order to harvest:
three patches of timber that totaled 25 hectares (61 acres) .
On the U.S. Forest Service lands in the Pacific Northwestern Region
(Region 6, Figure 8)$ private timber contractors construct more than
4.827 km (3,000 miles) of logging roads each year at a cost of $50
million. A special team was appointed to study road construction
performance on 63 recently completed roads located on every forest in
Region 6.—'
Principal conclusions and recommendations for sediment control included:
(1) On slopes greater than 607° no roads should be built until all other
alternatives hc.ve been exhausted. These include a change in the har-
vesting method; such as the use of skyline, helicopter, or balloon
logging systems,.
(2) In critical areas, assign the most experienced personnel to super-
vise the timber sales contract.
(3) More time and expertise should be assigned to geotechnical investiga-
tions before road construction. This includes geologic and soil surveys
to determine the most stable location for roads and for sources of gravel,
rock, and other subgrade materials.
(4) More flexibility should be given to timber sales contractors and
U.S. Forest Service personnel to adapt road construction techniques to
local conditions.
(5) Road construction should be started as soon as the weather is suitable
after the timber sales contract is awarded.
(6) Road construction equipment is often too large for efficient use in
building logging roads. Furthermore, newly designed skyline logging
equipment is too large for transport on the narrow logging roads.
Building wider roads invites more landslides and more erosion sediments,
and procedures have not been developed to fly the equipment to the site
by helicopter skycranes.
38
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39
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Although variations occur because of differences in forest ecosystems,
soils, geology, climate, and logging systems, specifications given by
Kochenderfer-22/ for the Appalachian Region are indicative of essential
techniques for the control of soil sediment resulting from the construc-
tion and use of logging roads. In the Appalachian Mountains, logging
roads should be laid out on grades between 3% (to permit surface water
to drain) and 10% (to avoid erosive velocities of water). Erosion on
newly-built roads can be reduced by seeding, with a mixture of fescue
grass and ladino clover, all bare soil in cuts and fills as soon as
possible and on all roadbeds after logging has been completed.
Filter strips are defined as undisturbed forest areas and should be
left to collect soil sediment between streams and 1 ,gging roads.
Kochenderfer recommends that in the Appalachian Region, roads should
be built at least 30 m (100 ft) from a stream to permit the unbroken
forest biomass to absorb the surface runoff water and to deposit soil
sediment before it pollutes the stream. Seepage areas in the logging
road can be drained by an open-top culvert set at an angle to permit
drainage, or by the construction of broad-based drainage dips.
Using the data from the H. J. Andrews Experimental Forest in western
Oregon, the Federal Water Pollution Control Administration!!/ compared
the logging road density, the acres needed for roads, and the percentage
of the roads wLth specific grades, for a road system that was laid out
systematically versus a system laid out at random (Table 6). The ran-
dom system had 12% more roads per unit area, 37% more area in roads, and
267% more roads with grades between 8% and 12%.
Sediment control should be engineered into road design and construction
during the planning phase. Erosion prevention techniques include the
building of logging roads with widths, grades, cut, and fills compat-
ible with soil and geologic stability; the maximum efficient use of
natural and artificial drainage1, and limitation of use of the roads by
heavy equipment when subgrades are saturated. For Logging operations
the equipment should be selected that causes the least soil disturbance.
The Coweeta Forest Watershed in North Carolina^4./ is proof that a great
deal of sediment control can be designed into the management of a water-
shed during and after logging operations. Water quality was monitored
from two sites in this watershed. The "logger's choice" site, which
had traditions 1 logging roads (Figure 9) and poor logging methods,
produced stream water turbidities as great as 5,700 ppm during storms
with average rainfall. A 144-hectare (356-acre) hardwood-covered water-
shed was engineered for sediment control with proper roads and proper
40
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TABLE 6
A COMPARISON OF ROAD PARAMETERS ON THE
H. J, ANDREWS EXPERIMENTAL FOREST IN WESTERN OREGON^/
Logging Road System
Parameter Systematic Random
Road density, km/sq km 3.08 (4.97) 3.47 (5.59)
(miles/sq mi)
Area needed for road construction, 10.65 (68.00) 14.6 (93.00)
hectares/sq km (acres/sq mi) of
watershed
Percentage of logging road system
having grades of (%)
0-4
4-8
8-12
Total
45.4
40.6
14.0
100 . 0%
37.7
10.9
51.4
100.0%
a/ "Industrial Waste Guide on Logging Practices," Federal Water
Pollution Control Administration, U.S. Department of the Interior,
40 pages (1970).
41
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42
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logging methods. Figure 10 shows the grassed surface of a road con-
structed to an engineered grade on part of a 73-hectare (180-acre) clear-
cut and a 32-hectare (80-acre) thinning operation. The maximum recorded
turbidity from this watershed was 400 ppm for a rainstorm which is ex-
pected to occur only once in 100 yr. The difference in water quality
from these two practices is graphically seen at the confluence of streams
discharging from each area. In Figure 11 the clearflowing stream is seen
on the left and the right-hand stream is discharging sediment from the
logger's choice area.
Some technology does not transfer successfully without radical adapta-
tion. This statement applies to the standard and routine technique in
the conterminous 48 states of constructing fire lanes to slow or halt
the spread of a fire. When the same practice is tried in Alaska on
fine-textured soils with permafrost, the surface of the permafrost melts,
the mineral soils above the ice prevent percolation, the ice may collapse,
and cavernous erosion as well as surface gullies result. The silts and
?s /
clays add soil sediments to nearby streams and lakes.—'
The techniques used to successfully control erosion on bare soils with
permafrost include the building of a terrace across the slope of the
fire lanes at intervals of 27 to 46 m (30 to 50 yd) to divert surplus
surface water into undisturbed vegetation along the sides of the fire
lane, and seeding an adapted grass and legume mixture over the entire
fire lane after liming and fertilizing the soil according to the
recommendations resulting from a chemical soil test. The most success-
ful grass seeded so far has been Manchar smooth bromegrass.
Another technique to control sediment that can be used in Alaska on
fire lanes is recommended by Lotspeich, Mueller, and Frey.^' This
system consists of bulldozing the natural and protective organic layer
back over the mineral soil of the fire lanes, after the fires have been
suppressed and before the bulldozers leave the area.
4.1.2 Sediment control by reforestation: The preferred way to control
sediment generation from previously forested but now eroding lands is
to plant trees or to encourage establishment of good tree stands by
natural regeneration. Tree planting on areas recently clearcut and on
eroded soils in forested areas has been an increasingly popular and
effective practice to enhance water quality. The U.S. Forest Service,
the state forest services, and the private forest industry have led in
this silvicultural activity. Furthermore, the U.S. Soil Conservation
Service has made a major contribution to the science and practice of
tree planting. Since 1930, 14.7 million hectares (36.3 million acres)
have been planted to trees.
43
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44
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Scientific guidance is given by the Soil Conservation Service to private
landowners in the selection of forest tree species that are suitable to
the soils. Soil interpretations for woodland use are based upon 22,000
plots of trees planted or managed on model soils throughout the United
States where climate and soils favor tree growth. On the test plots are
measured the site index (height over age at 50 or 100 yr) , soil sediment
erosion hazard, equipment limitations, windthrow hazard, and annual
growth rate in volume of
Information on woodland suitability groups of soils is incorporated in
individual farm/ranch conservation plans and also is included for all
soil mapping units in published county soil survey reports.
An example of how to use the woodland suitability groups of soils is
presented in a recently published soil survey report of Chilton County
in central Alabama. _?JV The soil survey report indicates that 26 hectares
(65,000 acres) of land in Chilton County are in need of tree planting for
one or more reasons, including soil sediment control for the enhancement
of water quality. To assist in selecting the most suitable tree species
for planting, all soil mapping units in the County are placed into one
of 15 woodland-soil suitability groups, based upon their ecological
similarities. Each of the 15 groups of soils on the County soil map
are assigned a corresponding group of adapted (suitable) trees of high
commercial value with predicted site index and volume of annual growth
per acre.
"Soil-Vegetation Surveys in California" describes three kinds of maps:
generalized soil maps, soil-vegetation maps, and timber-stand/vegetation
cover maps.
Soil maps are available for a part of California on a scale of 2.04 cm/km
(1/2 in. /mi. )^2./ Information shown on the soil map is: soil series, soil
depth classes, dominant trees/shrubs, dominant grasses, and timber pro-
duction site index classes. Soil-vegetation maps are printed on a scale
of (8.16 cm/km) 2 in. /mi. On these maps are shown soil series; vegetation
types such as forest types, grass associations, meadows, and marshes; site
quality potential for timber production; and miscellaneous areas such as
bare rock. Timber-stand/vegetation cover maps were published at one time,
but their publication has been terminated. These maps can be used to
assist in determining what species to plant for the maximum assurance of
success.
Scientific guidance is thus readily available from many sources the
U.S. Soil Conservation Service, the U.S. Forest Service, the state
46
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forestry and natural resource services, the state agricultural experiment
stations, and the state departments of agriculture) to assist in selection
of a plan to plant forest trees of high value on watersheds to enhance
water quality.
4.1.2.1 Reforestation of watersheds in Tennessee: Lull and Reinhart22/
quote results of sediment reduction resulting from tree planting and check
dam construction on the White Hollow and Pine Tree Branch watersheds in
Tennessee. Planting about one-third of the severely eroded White Hollow
watershed resulted in a reduction of an average storm sediment yield from
6.6 metric tons (7.3 tons) in 1935-1936 to 0.27 metric tons (0.3 tons)
in 1954-1955— -a reduction of 96% in 20 yr. Planting two- thirds of the
Pine Tree Branch watershed in 1942 reduced sediment yield from 155.5
metric tons/hectare/yr (24.3 tons/acre/yr) to 2.46 metric tons/hectare/yr
(1.1 tons/acre/yr) in 1960 — again a reduction in sediment of 96% in 18 yr.
Lull and Reinhart, also in analyzing and summarizing the work of Wark and
Keller, stated that in 15 subbasins of the Potomac River, the percentage
of land area with forest cover was inversely related to the sediment
yield, as follows (Table 7):
TABLE 7
INFLUENCE OF FOREST COVER ON CONTROL
OF SEDIMENT YIELD BY EROSION
Land Area Sediment Yield
with Forest Cover Metric Tons/Sq Km/Yr
(Tons/Sq Mi/Yr)
20 140 (400)
40 70 (200)
60 31.5 (90)
80 15.75 (45)
100 7.7 (22)
4.1.2.2 Reforestation in Mississippi: In north central Mississippi (on
abandoned, gullied, loessial, silt loam, acid soils) surface and gully
erosion is as serious as in any area in the U.S. For many years it has
been common practice to plant trees on such sites to control soil losses
47
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and sediment pollution of streams. One problem is to determine which
forest tree species or mixtures of species are most effective in in-
creasing infiltration and thereby reducing surface water runoff and
sediment.
McClurkin^L/ studied the change in soil infiltration that took place
during 1951 and 1966 under several species and mixtures of species.
The data are in Table 8.
TABLE 8
COMPARATIVE CHANGES IN WATER INFILTRATION
RATES IN SURFACE SOILS FOLLOWING 15 YEARS OF TREE GROWTH
Infiltration
Rate
Species Planted Year mm/hr
Red cedar plus loblolly pine 1951 42
1966 132
Shortleaf pine 1951 38
1966 141
Loblolly pine 1951 85
1966 187
Red cedar plus shortleaf pine 1951 43
1966 43
Red cedar 1951 133
1966 84
The data indicate that during the 15-yr period increases in infiltration
were recorded for: red cedar plus loblolly pine, shortleaf pine, and
loblolly pine. Red cedar plus shortleaf pine did not increase infiltra-
tion, and soil under red cedar planted alone decreased in infiltration
rate during the period.
Ursic—' monitored runoff and sediment from three watersheds in north
Mississippi, each comprising 2 to 3 acres. The background data were
collected during 1960-1963, after which Watersheds I and III were
burned and planted to loblolly pine. Watershed II remained untreated
to serve as the control.
48
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Sediment yields from Watersheds I and III increased by factors of 18
and 78 during the first year after burnings and the increases appeared
to have persisted from 2 to 4 yr (Table 9). Although further comparisons
may be somewhat masked by the natural improvement of the vegetation on
the control, average sediment yield from each of the two treated units
5 to 7 yr after the pine was planted was less than one-half that during
the years prior to planting.
TABLE 9
EFFECTS OF BURNING ON SEDIMENT PRODUCTION
AND OF TREE PLANTING ON SEDIMENT CONTROL!/
Kilograms of Sediment per Hectare per Year (Oven-Dry Basis)
(Pounds of Sediment per Acre per Year)
Treatment
Year(s)
No Burning,
No Planting
of Trees
(Watershed II)
Burning and Planting to
Loblolly Pine Trees
1960-1963£/
1964
1965
1966
1967
1968 .
1969
1970
635 (690)
588 (639)
259 (281)
115 (125)
137 (149)
128 (139)
91 (99)
193 (210)
(Watershed I)
77
1,418
81
30
22
53
29
24
(84)
(1,542)
(88)
(33)
(24)
(58)
(32)
(26)
(Watershed III)
68
528
477
43
99
29
31
35
(74)
(5,759)
(519)
(47)
(108)
(32)
(34)
(38)
ai/ Ursic, S. J., "Hydrologic Effects of Prescribed Burning on Abandoned
Fields in Northern Mississippi," USDA Forest Service, Research
Paper SO-46. 20 pages (1969). Note: Data from 1967 through 1970
were transmitted by letter, Ursic to Donahue, dated 5 June 1973,
with this caution: ". . .please consider these data tentative. . .
b_/ Watersheds calibrated during 1960-1963 before treatment.
4.1.2.3 Sediment control by reforestation on clearcut areas without
burning: It has been the traditional and recommended practice by
professional foresters that tree limbs, tops, and other wood material
be burned after a clearcutting operation to remove the fire hazard and
49
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to expose the mineral soil required for the reforestation of intolerant
species of trees. For 8 yr now, U.S. Navy Foresters-^' have demonstrated
that it is technically practical to establish new Douglas fir stands by
artificial seeding and without burning, on level land and on slopes up
to 25%. The following report has been prepared by the U.S. Navy and is
here reported for the first time exclusively for this document.
THE U.S. NAVY REPORT
For the past 8 yr, Navy foresters in the Puget Sound area have been
direct-seeding Douglas fir (Pseudotsuga menziesii) without burning the
slash created by clearcutting operations. The slash remaining from
logging operations is bunched or piled in windrows by using a crawler
tractor equipped with a brush blade (Figure 12).
The windrow system of slash disposal was first used by the Navy in 1965
at Camp Wesley Harris, a Marine Corps rifle range located near Bremerton,
Washington. The sale covered 4 hectares (10 acres) on which slash left
from logging was windrowed in 1965. In March 1966 the area was seeded
with endrin-treated Douglas fir seed, using 0.46kmof seed per hectare
(1/2 Ib of seed per acre) applied with a cyclone seeder. At the present
time, the area contains a fully stocked stand of Douglas fir.
The windrow method proved so successful that its use was continued.
The following additional areas have been windrowed and seeded to date:
Station Hectares (Acres) Date Logged Date Seeded
Indian Island 20 (50) 12/65 3/66
Bangor Annex 19 (48) 9/66 2/67
Camp Harris 16 (40) 12/66 2/67
Lake Hancock 6 (16) 12/66 2/67
Bangor Annex 13 (31) 5/68 2/69
Indian Island 18 (45) 2/69 3/69
Bangor Annex 16 (40) 7/69 2/70
Bangor Annex 8 (20) 7/69 2/70
Indian Island 24 (60) 8/71 2/72
All the areas listed above are fully stocked with Douglas fir (Figure 13).
Another 20 hectares (50 acres) of Bangor Annex was logged during May 1973
and will be direct-seeded in February 1974. Windrowed slash has deteri-
orated at a more rapid rate than had been anticipated, and soil particles
50
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51
-------
Figure 13 - Five-Year Old Douglas Fir Trees That Were Seeded
Directly onto a Slash Windrowed Area, without
Control-Burning. (Courtesy Department of the Navy)
52
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mixed with the slash support thrifty Douglas fir seedlings. Some
natural regeneration of such species as western hemlock (Tsuga heterophylla),
western white pine (Pinus monticola), western red cedar (Thuja plicata),
lodgepole pine (Pinus contorta) and grand fir (Abies grandis) takes place,
but not of sufficient numbers to seriously compete with seeded Douglas fir.
Douglas fir is considered as subclimax in the area, and fully stocked
stands are not likely to become established under natural conditions due
to the higher degree of tolerance of some of the other species. The pre-
dominating deciduous type, usually on wetter sites, is red alder (Alnus
rubra), associated with bigleaf maple (Acer macrophyllum). Early seeding
of Douglas fir following harvest and windrowing is necessary to establish
this valuable species to the desired degree of stocking, particularly on
the more moist sites. Regeneration of Douglas fir by direct seeding has
the advantage of getting the species established for an early start in
competition with red alder. Where seeding is left to nature, red alder
is capable of suppressing Douglas fir on many sites in the area. Direct
seeding of Douglas fir at an early date following logging tends to offset
the advantage given alder.
Most soils are of glacial origin (glacial drift and outwash) and tend to
be gravelly or sandy on the surface at most locations. They vary from
light to medium in texture and from shallow to moderately deep. Some soils
are underlain by a cemented hardpan layer of varying thickness which re-
tards vertical movement of water.
Terrain where the method has been used varies from almost flat to slopes
of 25%. From the standpoint of environmental protection, windrowing
accomplishes two purposes. Emission of pollutants into the air is pre-
cluded, and soil erosion is checked. The exclusion of fire as a means
of slash disposal is desirable in fuel and ammunition storage areas
because of the safety factor.
The following clause was used in the timber sales contracts, which re-
quired slash treatment by windrowing:
"The slash shall be disposed of by bunching or piling in windrows.
The windrows shall be continuous strips not more than 20 feet
wide and not less than 75 feet apart, such measurements to be
determined at ground level. The windrows shall be at least 75
feet from any existing road and standing timber. As a fire pre-
cautionary measure, windrows shall be broken into segments approx-
imately 5 chains (330 feet) in length. The break between segments
shall be no less than the width of a dozer blade. When the grade
exceeds 15 percent for an area of more than one acre, windrows
shall be constructed on the contour at right angles to the direction
53
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of the slope. Windrows shall be constructed by a crawler
tractor equipped with a brush blade having a minimum of seven
teeth. These teeth shall project at least 12 inches below the
bottom of the blade."
No problems have occurred to date using the windrow system. It is
estimated that the cost of windrowing slash is between $2.12 and $4.25
per cubic meter ($5 and $10 per thousand board feet) of harvested wood.
It is reported the windrow system of slash disposal and direct seeding of
Douglas fir following harvest has proven successful beyond any doubt, as
indicated by field observations and the pictorial evidence in Figures 12
and 13. The Navy will continue the use of this method on areas where
regeneration of Douglas fir is desired.
4.1.2.4 Reforestation for sediment control on surface mine areas: The
State of Pennsylvania passed a Conservation Act in 1945, amended in 1963,
requiring surface mine operators to post a bond equal to $247 per hectare
($100 per acre) of mine spoils, refundable when the spoils have been
satisfactorily revegetated with grasses plus legumes or trees/shrubs.
From 1945 to 1S63, 3,400 hectares (84,060 acres) of strip mine spoils
had been been planted to trees/shrubs. The Research Committee on Coal
00 /
Mine Spoil Reve;getation in Pennsy Ivan Laid' has been the technical body
to coordinate research on this subject.
Spoils from bituminous mines are extremely variable as to acidity (pH) ,
stoniness, and slope, with acidity being the principal determinant of
success or failure of vegetation. Acidity may vary from below pH 3.5
to above 7.5, stoniness may vary from few to 100%, and slope from zero
to more than 25%.
Trees recommended for planting on median (Group C) spoils include Austrian
pine, jack pine, pitch pine, red pine, scotch pine, white pine, Japanese
larch, black locust, red oak, and European alder. Shrubs approved are
autumn olive, lespedeza bicolor, and mugho pine.
Before planting black locust trees, an application of fertilizer con-
sisting of 37 km of N and 74 km of P205 per hectare (40 Ib of N and
80 Ib of T?2®5 Per acre) is recommended.
4.1.3 Sediment control by planting grasses and legumes: Stabilization
of disturbed soils and geologic materials in forest areas, especially on
new road cuts and fills and on logging road roadbeds when current logging
operations have ceased, is usually more rapid when grasses and legumes are
seeded than when trees are planted.
54
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On the H. J. Andrews Experimental Forest in western Oregon, sediment
yields were compared from a bare and seeded-to-grass road cut (Table 10),
as reported by Wollum.£ft'
TABLE 10
COMPARATIVE SEDIMENT YIELD FROM BARE AND SEEDED ROAD CUT
ON THE H. J. ANDREWS EXPERIMENTAL FOREST IN WESTERN OREGONi/
Sediment Yield
Condition Period of Kilograms/Hectare
of Plot Measurement (Tons/Acre)
Bare 9/58 to 9/59 23,370 (12.7)
Seeded to grass 9/59 to 9/60 7,728 (4.2)
Seeded to grass 9/60 to 9/61 4,232 (2.3)
aj Wollum, A. G., "Grass Seeding as a Control for Roadbank Erosion,"
USDA Forest Service Research Note 218. 5 pages (1962).
The plot was fertilized with 147 kg/hectare (160 Ib/acre) of 16-20-0
fertilizer and seeded with an 86-8-4 mixture of ryegrass, meadow fescue,
and highland bentgrass at a rate of 90 kg/hectare (98 Ib/acre) in April.
The sediment yield was reduced by 677o the first year and by 82% the
second year.
Planting of grasses/legumes on strip mine spoils in Pennsylvania has
been mandatory since 1945. From 1945 to 1963, 7,885 hectares (16,489
acres) of mine spoils had been revegetated with grasses/legumes.
Recommended for planting on the Group C and Group D (inferior) classes
of spoils are tall oatgrass, tall fescuegrass, and redtop grass. The
one legume recommended is lespedeza sericea.^3_/
4.1.4 Streamcourse classification for erosion control: "Title 2400—
Timber Management" and other "Titles" of the U.S. Forest Service Manuals
state environmental objectives very clearly and expect compliance in the
forest, but at this time there is inadequate organization and manpower
for relevant research and demonstrations.
55
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Monitoring of pollution and compliance with environmental objectives
during implementation of a timber sale contract is a developing tech-
nology that must: yet regionalize appropriate techniques in methodology
to control pollution at the time timber is harvested.
The "Title 2400--Timber Management" manual, dated May 1968, has made an
initial step to classify area streams and define ways to protect the
stream channel from erosion during the duration of a timber sale opera-
tion. Section 2456.5 of this document headed, "Protection of Streamcourses
(B6.5 -C6.5)" provides that each sale or other use of national forest
timber will be authorized only after the approving officer is satisfied
that practical fire prevention measures and methods of cutting and
logging are prescribed which will secure favorable conditions of water
flows. The timber sale contract provides two basic provisions to accom-
plish this objective. They are B6.5 and R5-C6.5. The use of these two
provisions requires classification of Streamcourses on the sale area
based on susceptibility to damage. This directive is intended to be a
guide to streamcourse classification for application of these provisions
of the timber sale contract.
"Streamcourse classification. All Streamcourses within a proposed timber
sale area shall be classified during the field examination stage of sale
preparation on the basis of their susceptibility to damage by logging
activities. At this time, those Streamcourses that have well defined or
scoured channels, that show evidence of developing sufficient head of
water to move debris or erode the channel, or which may develop such
characteristics if diverted or blocked by logging activities, will be
classified as (!L) 'sensitive,' or (2) 'resistant' based on the following
criteria:
"SENSITIVE Streamcourses (Figures 14 and 15) include all perennial
streams except l:hose with solid rock streambeds and streambanks. Inter-
mittent Streamcourses with riparian vegetation and those with unstable
streambeds or streambanks are also classified as sensitive. Segments
of streamcourse so classified are to receive the protection specified
in B6.5.
"RESISTANT Streamcourses (Figures 16 and 17) include perennial streams
with solid rock streambeds and streambanks and intermittent streams with
stable channel conditions and little or no riparian vegetation. Stream-
courses classified as resistant receive the protection specified in
C6.5.
"Other Streamcourses on the sale area are protected by careful location
of roads, skid trails and other developments and by erosion control work
56
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•M*
„*•'. '
\** * *» 4f ,
Jt ' «.<• ^ * W"
r f<'.^*-f?
•y 4faSiu'^v
' J^Waii:?c£
-a^'-AS.'-'vfir^
y
Figure 14 - A Typical Perennial Streamcourse That Should
Be Classified as Sensitive (Courtesy U.S.
Forest Service)
Figure 15 - A Typical Sensitive Intermittent Streamcourse
Before It Becomes Dry. (Courtesy U.S.
Forest Service)
57
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Figure 16 - Resistant Streamcourses Stabilized by Solid
Rock or Heavy Boulders. (Courtesy U.S.
Forest Service)
Figure 17 - A Resistant Streamcourse. (Courtesy U.S.
Forest Service)
58
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specified for the entire sale area. These are usually ephemeral in
character. They should not be used as skid trails. Locations for
necessary crossings must be chosen carefully. Careless logging or
road construction can transform these streamcourses into eroding
channels. Authority to regulate road and skid trail location is given
in B5.1 and C6.4. Other provisions of the contract which provide pro-
tection for these streamcourses include B6.21, B6.61, and C6.6.
"Streamcourses often have segments falling into each of these categories.
Ordinarily the classifications should be applied to segments one-half
mile or longer in length."
In addition to current efforts of the U.S. Forest Service, the states
of Oregon and California, and the Department of Natural Resources in the
State of Washington have made individual efforts to anticipate water
pollution control problems. To illustrate, the State of Washington has
developed a system for classifying streams for the purpose of refining
regulations relating to forest road building and logging transport
systems. The point system of classification, Table 11, is based upon
six stream characteristics to be used in placing streams into one of
five stream classes. The six stream characteristics are: (1) water
flow continuity; (2) size during mean annual flow; (3) recreational use;
(4) other water uses; (5) fish life present; and (6) type of streambed.
All public forest lands are harvested by many private contractors who
operate under a highly competitive auction bid system. The contractor
is normally a local businessman who is usually concerned about the long-
term productivity of the forests. In periods of high demand and limited
supply of timber offered for sale» some operators become careless about
logging practices that pollute the streams.
More current adapted technology should be incorporated during the timber
harvest operation under timber sale contract terms. In addition, more
accurate monitoring techniques should be developed to achieve a more
satisfactory basis for establishing better guideline standards relating
to the impact of individual timber sale operations on surface water
quality.
4.1.5 Grazing control: Cattle grazing in hardwood forests can result in
a partial destruction of tree reproduction, and compaction of the soil to
depths as much as 0.6m (2 ft). Compacted soil has less infiltration
capacity, and surface runoff and erosion usually result.
Lull and Reinhart—' quote Hays et al., on the damage of domestic live-
stock to watersheds in Wisconsin.
59
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TABLE 11
STATE OF WASHINGTON
DEPARTMENT OF NATURAL RESOURCES
Stream Classification Key (TSD-8-8-71)
Sale No. Stream
Points
A. Water Flow Continuity
1. Present above ground year round 10
2. Present above ground most of the year .... 5
3. Present above ground only during
periods of runoff 0
B. Size of Stream During Mean Annual Flow
(Average Flaw)
1. Width in 1-ft increments (points per
increment) 3
2. Depth in 4-in.increments (points per
increment) 1
3. Add 1 point for each 8% of stream
gradient (3 points maximum) 0
C. Recreational Use
1. Existing developed camp site and trails
along water 10
2. Substantial recreational use, but no
developed sites or trails 8
3. Proposed development or substantial
recreational use expected within
next 10 years 4
4. Periodic or infrequent recreational use,
such as hikers, hunters, etc 2
5. Rarely used for any recreational purpose . . 0
60
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Sale No.
TABLE 11 (Concluded)
Stream Classification Key (TSD-8-8-71)
Stream
Points
D. Use of Water
1. Human consumption within 3.2 km (2 mi)
downstream 10
2. Human consumption 3.2-16.1 km (2-10 mi)
downstream 5
3. Human consumption more than 16.1 km
(10 mi) downstream 3
4. Livestock consumption within 1.6 km
(1 mi) downstream 7
5. Livestock consumption 1.6 to 8 km
(1 to 5 mi) downstream 3
6. Recreational use such as swimming within
1.6 km (1 mi) downstream 3
7. None of these 0
E. Fish Life
1. Supports both anadromous (migrating) and
sport fish or used as direct source of
fish hatchery water 10
2. Supports only sport fish 8
3. Potential area for sport or anadromous
fish 4
4. Does not support or have potential of
supporting fish (too steep, broken or
lack of water year round) 0
F. Type of Stream Bed
1. Well-defined channel with rock and
gravel bottom -*
2. Well-defined channel with gravel and
mud bottom 3
3. Well-defined channel with mud and grass
bottom •*-
4. No well-defined channel with mud and
grass bottom "
H
H H >
H H H H >
+ 01
m
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A nongrazed woodlot lost no soil, whereas a comparable grazed woodlot
lost 257 kg/hectare/yr (0.14 ton/acre/yr). By comparison, at the
Coweeta watershed in southern North Carolina during the ninth year
of grazing by 'Livestock,the maximum turbidity in the stream was 108 ppm
vs 30 ppm from an adjoining ungrazed woodland.
It is very important that grazing on forest land be carefully controlled
and inspected at regular intervals. Overgrazing, where a livestock
population is too dense for available grass, particularly during dry
periods, can result in severe tree damage from eating the tops of small
trees, excessive erosion on "cow paths'r and serious water pollution caused
by the cattle cooling themselves in the stream.
4.1.6 Control of bark sediment in water: Bark fragments scuffing off
logs in water Is a local problem in some areas. The Pacific Northwest
Pollution Control CounciL-Li' has released a report on control of the
environmental effects of floating/rafting logs down public waters and
storing them i:i waters before use by mills, summarized as follows:
1. Log transport and storage does sometimes pollute public waters and
interferes with small craft navigation. Under these conditions the
practices shouLd be restricted or eliminated.
2. The free-fall of logs from trucks into waters must be stopped
because this is the principal cause of bark debris.
3. Both floating and settled bark should be collected and placed on
dry land.
The report does not address itself to the cost of implementing these
recommendations, nor does it estimate the economic tradeoffs and impact
on the region if the recommendations should be implemented through law.
In addition the report does not document the extent of damage caused by
the bark.
4.2 Control of_ Pollution from Pesticides
The EPA Pesticide Study Series Report No. 7, "The Movement and Impact of
Pesticides Used in Forest Management on the Aquatic Environment and
Ecosystem," presents a thorough and current review of this subject. It
describes forest application techniques, route of pesticides into the
water environment, and the impact of pesticides on the aquatic environ-
ment and the forest ecosystem, with emphasis on experiences in connection
with the control of the gypsy moth in New York State.
62
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This comprehensive study documents how little is known about the fate
and effects of all pesticides, including forest pesticides, in the
environment after application. Control methods must, therefore, be
formulated on a generally unsatisfactory base of knowledge of the true
environmental impact of pesticide usage. Most of the pesticide use in
forests is, therefore, as in other use areas, practiced for economic
benefit at a calculated risk to environmental quality. The risks are
assumed to be small relative to benefits. The element of uncertainty
in this rationale is one reason that the basic role of pesticides in
silviculture is lately being reevaluated. A second reason is the growing
conviction that a forest is too complex an ecosystem to be treated pro-
fusely with pesticides—that we know so little about the ecosystem that
pesticide use is likely to lead to unwanted, basic changes in the system
which may offset benefits. Pesticide usage is for these and other reasons
declining, and other controls are being substituted.
Rules and guidelines for pesticide use have been well stated by Witt and
Baumgartner,.36/ Benton,—/ and Schlapfer,^§i!2/ The rules are generally
qualitative and are helpful, but much local interpretation and judgment
are required in development of pesticide programs.
Selection of a pesticide for effectiveness and minimum toxicity to the
environment is a form of pollution control. Low order toxicity to non-
target species, including aquatic life, is preferred for obvious reasons.
The guidelines for pesticide selection include the following: low
persistence in the environment; low susceptibility to transport through
the environment (nonvolatile, water insoluble); highly selective (minimum
toxicity to nontarget species); biodegradable to harmless end-products
and not subject to bioaccumulation in the food chain; and minimum toxicity
to animal and aquatic life.
Adherence to rules developed for application will minimize pollution from
pesticides. These rules include:
1. Application when rain, fog, wind, and air temperature are most
favorable for assuring that a maximum percentage reaches target species.
2. Avoiding watercourses, and leaving if possible, a buffer strip
between streambeds and treated areas. Buffer strip widths of 30, 15,
7.5, and 4.5 m (100, 50, 25, and 15 ft) have been recommended by
Schlapfpr.38,39/ for the application of herbicides by aerial, ground
vehicle, hand spraying, and hand injection methods, respectively.
3. Proper disposal of all containers and pesticide residues.
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4. Applicatian specifically to areas requiring treatment rather than
blanket treatment of diseased and healthy areas. It has been proposed
that aerial application of pesticides be done mostly by helicopter to
enable more accurate placement on target species.
Finally, policy regarding the mode and extent of use vitally affects the
methodology for controlling pesticide pollution, particularly with regard
to alternates to chemical pest control, namely biological control, control
through cultural systems based on knowledge of the ecology of forests,
and mechanical control methods. This basic issue is the subject of
current debate, and the present study can only recognize that evolving
concepts of pesticide use will yield, in the future, a modified set of
pollution control problems together with updated control measures
founded more firmly on fact than at present. Evolving policy has in
recent years resulted in cessation of the use of certain pesticides; a
general reduction in the quantity of pesticides applied to forests and a
reduction in treated acreage; decreases in the extent of prophylactic
treatment; and increased reliance on natural and cultural methods of pest
control. This general trend, together with conscientious adherence to
guidelines for selection and application of pesticides, should sum up to
worthwile reductions of the hazard to the aquatic environment as well as
the environment in general.
For the present and near future (5-10 yr), methods available for control
of pesticide pollution from silvicultural activities will,therefore, con-
sist of adherence to accepted guidelines for use in a plan which calls
for optimization of chemical pest control. Optimization as it is used
here denotes use to the extent deemed necessary.
4.3 Control of Pollution from Fertilizers
There are strong pressures to establish "principal use" categories for
all public lands, including forest lands. This mood-of-the-day extends
even into the management of private timber lands. With an accelerating
demand for paper and lumber, the logical response for the public and
private timber manager is to allocate the more productive and less
fragile lands: to timber production and to apply all available production
technologies to enhance tree growth--including the judicious use of
fertilizers.
Groman^J)/ has reviewed the current status of forest fertilization. At
present, fertilizer use on forest, mostly nitrogen, is centered in the
Pacific Northwest Douglas fir region and in the Southern pine region.
64
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In addition, the young stands of commercial redwood in northern
California and the western-hemlock-sitka spruce along the coasts of
Alaska, Washington, and Oregon are judged to have a potential for
responding economically to application of fertilizer.
In the Pacific Northwest, forest fertilization with nitrogen started in
1965, reached a level of 48,165 hectares (118,750 acres) in 1970, and is
anticipated to be 100,000 hectares (250,000 acres) per year from 1975-1980.
Response of Douglas fir to nitrogen fertilization has averaged about 30%
during a 5-7 yr period; trees as old as 300 yr have shown a growth
acceleration.
In the South, the pines on well-drained soils respond well to fertiliza-
tion. Here nitrogen alone is expected to enhance growth by about 5% a
year. A second area of present and predicted future response is the
flatwoods coastal plains, where both nitrogen and phosphorus give
increased growth of pines. Forest fertilization in the South started
on a commercial basis in 1963, and in 1971 an estimated 44,500 hectares
(110,000 acres) had been fertilized.
Helicopters are preferred for use in fertilizing the forest. Environ-
mentally, they are safer than fixed-wing aircraft because they can fly
slower, and, therefore, avoid all streams and lakes.
A summarized brief on the relationships between forest fertilization and
water quality is as follows:
1. The potential exists for increasing ammonia and nitrates in streams
and lakes to environmentally hazardous levels; so far no incidents have
been reported.
2. Unlike cropland that is usually devoid of growing plants when most
fertilizer is applied, forest soils always contain a mass of roots at
variable depths that are continuously absorbing nitrogen in the ammonium
and nitrate forms.
3. A forested soil is so efficient in recycling nutrients that it is
used in many places as an ideal, environmentally safe place to spray
municipal effluent (Sopper) ._tl'
Possible pollution hazards from fertilization that must be avoided have
been stated by Reinhart:^_2./
65
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1. Increased nutrients in streams and lakes.
2. Increased organic matter in watercourses.
3. Decreased water yield.
4. Damage to nontarget species.
5. Air pollution.
Because of the lower cost of application, forest fertilization has been
practiced with solid fertilizers distributed by aircraft. With many
agricultural and horticultural crops, spraying leaves with liquid urea
fertilizer has been proved more efficient than application to the soil.
Vu££yz~!.i compared foliar application to ground application with loblolly
pine seedlings under greenhouse conditions, and obtained data reproduced
in Table 12. His tests indicate that foliar application (therefore, aerial
spray application) less effectively utilizes nutrient values than does
soil application.
Methods for control of pollution from fertilization are based on many of
the guidelines which apply to pesticide use (Table 12).
1. Fertilize only when a soil test indicates that benefits are expected
to be economically worthwhile.
2. Fertilize at rates which do not exceed the adsorption capacity of the
soil and the uptake capability of timber stands.
3. Frequent fertilization at low rates is environmentally safer than
infrequent application at high rates.
4.. Do not spray over watercourses, and leave buffer strips between
streams and fertilized areas.
5. Apply fertilizers when wind drift is minimal.
6. To the extent that rainfall can be predicted, avoid fertilization in
periods of hee.vy rainfall.
7. Coarse pellets of fertilizer are environmentally safer than fine
pellets; and liquid fertilizers have the greatest water pollution
hazard.
66
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TABLE 12
COMPARISON OF NITROGEN FERTILIZER APPLIED
ON FOLIAGE AND ON SOIL FOR LOBLOLLY PINE£/
Treatment
56 kg (150 Ib) N on
Foliage
One Application
Five Applications
56 kg (150 Ib) N on
Soil
112 kg (300 Ib) N on
Foliage
One Application
Five Applications
Post-Treatment
Height Growth
Ammonium
Nitrate Urea
(cm) (cm)
3.7
3.4
14.5
12.1
8.4
4.6
4.1
4.7
8.1
9.2
Foliage Weight
Ammonium
Nitrate Urea
(g) (g)
4.33
4.10
9.53
6.67
5.20
2.40
3.26
5.10
3.93
4.86
Foliage N
Ammonium
Nitrate
0.73
1.17
1.04
0.85
0.97
Urea
0.77
0.70
0.93
0.85
0.83
aj Duffy, Paul D., "Loblolly Pine Seedlings Respond to Foliar Nitrogen Fertili-
zation," JJSDA_Jfoj^£t_J5e_rjn.c^_jte^ 4 pages, 1971.
67
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Fertilizers are presently used sparingly on forests, in comparison to
agricultural use, and the impact on water is, therefore, limited to
specific watersheds and is relatively insignificant in the macro sense.
If the assumption that forest management will become more intensive in
the future proves to be correct, now is the time to initiate research
studies and planning action aimed at: management and control of the
potentially increased pollutional loads from fertilization.
4.4 Control of Pollution from Fire Retardants
Most fire retardants are delivered to fires by fixed-wing aircraft at
an estimated cost of material plus spreading of $0., 26/liter ($l/gal.).
Historically, fire retardants have been plain water, water with a
wetting agent added, borates, bentonite clays, and currently Fire-trol
(ammonium sulfate) and Phoschek (diammonium phosphate). Borates are
herbicides that are no longer used extensively because of their hazard
to the environment. Bentonite clays lost popularity because the slurries
were too slippery for fire fighters to retain their footing in steep
terrain. Bentonite sediments are nontoxic but when applied in or near
streams, remained suspended for long periods of time. Both of the
proprietary formulations of ammonium sulfate and diammonium phosphate
liberate ammonia which is toxic to Eish if released directly into the
water. In addition, both nitrogen and the phosphorus in excess can
cause eutrophication of streams and lakes. The environmental hazards
of fire retardant use are thus essentially the same as the hazards
associated with fertilization.
Annually there are about 42 million liters (11 million gallons) of all
types fire re.'tardant materials used (Table 13), with the U.S. Forest
Service using about one-half the total amount, followed by the California
Division of Forestry using over 11.4 million liters (3 million gallons)
of material annually.
Unless the ammonium sulfate and diammonium phosphate are accidentally
applied to streams or lakes, the hazard to the water environment is rare.
Normal use of these fire retardants consists of dropping them from a
fixed-wing aircraft ahead of the fire, in an inverted V pattern, at or
beyond the crest of a ridge. Dropped at this location, the rate of
spread of the fire is slower, fire fighters are more effective, and the
distance from streams is usually so far that pollution is minimal.
The considerations involved in development of guidelines for fertiliza-
tion (Section 4.3) apply to fire retardant use. However, the fire
68
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TABLE 13
ACTUAL CONSUMPTION OF FIRE RETARDANTS IN 1966£/
Agency
U.S. Forest Service
California Division of Forestry
Bureau of Land Management
Southeastern States
State of Washington
State of Oregon
Total
Total Liters (Gallons)
Used in 1966
22,490,000
12,161,000
3,781,000
1,802,000
190,000
106,000
(5,942,090)
(3,212,600)
(999,150)
(476,320)
(50,000)
(28.000)
38,730,000 (10,708,160)
al Hartong, AllanL., "An Analysis of Retardant Use," Intermountain
Forest and Range Experiment Station, U.S. Forest Service,
Research Paper INT-103, 40 pages, August 1971.
fighter has little control over the time or the place. The most important
guideline for fire retardant use is avoidance of surface waters in the
application pattern.
4.5 Control of Thermal Pollution Resulting from Solar Energy
Temperature increases of water in streams from silvicultural activities
are due to the cutting of shade-producing riparian trees and shrubs;
and increases in stream water temperature are thought to be harmful to
aquatic life.
The former Technical Advisory and Investigation Branch of the Federal
Water Pollution Control Adminstrationft^L/ summarized the relationship
of stream and lake temperature to aquatic life in this way:
1. All chemical reactions in water vary with temperature, generally in-
creasing with increasing temperature. One principal exception is the
solubility of oxygen in water, which decreases with temperature.
Furthermore, an elevation of water temperature hastens bacterial de-
composition and oxygen is further decreased in the process. The rate
of decomposition increases to about 30°C (86°F).
69
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2. Cold-water nonanadromous fish such as trout thrive best in water
below 14.5°C (58°F).
3. The maximum temperature tolerated for a given species of fish varies
with the rate of heating, the size of the fish, and its physiological
condition.
4. Substances toxic to fish are more toxic at higher temperatures.
5. There is no one ideal temperature for a particular species of fish.
Reproduction requires one range of temperatures and larval development
another range. From a specific water area, a fish species may be absent
in summer and present during winter months.
6. An increase in temperature of a segment of a stream may block normal
migration of anadromous species.
7. Some waters may be too cold for certain species of fish.
8. As water temperature increases, the predominant {species of algae will
change from diatoms to green algae to blue-green algae. Certain blue-
green algae are capable of fixing atmospheric nitrogen and thus
hastening eutrophication of waters.
Angular canopy density is proposed by Brazierz-1' as a better measure of
shading ability of a stream than width or height of vegetation. The
angular canopy density was measured at solar noon (zenith) by a
densitometer designed for the purpose. It is hypothesized that a buffer
strip reduces elevation of stream water temperature by providing shade.
Data obtained in Brazier's study indicated that maximum shading ability
was obtained by a buffer strip 24 m (80 ft) wide, and 90% of maximum by
a 17-m (55-ft) wide buffer. Conclusions included the statement that the
forest ranger should decide the proper width of buffer strip for each
stream based upon the stream width, depth, velocity, initial temperature
and height of the vegetative buffer.
Technologies to control thermal pollution in northwestern U.S. were
summarized by Brown, Swank, and RothacherZ^./ as follows:
Daily temperature variation in undisturbed streams may be about 2.2°C (4°F)
or more. This value will rise to about 5.6°C (10°F) or higher when all
shade along streams is removed. Cooling of waters downstream is due
primarily to inflow of cooler tributary streams rather than by cooling of
warmer waters due to the presence of shade. The shade does not cool
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water in streams; it merely reduces the variations in stream tempera-
ture.
Buffer strips of vegetation along streams is the only practical way to
keep streams cool. The width of the buffer strip must be determined
by on-site inspection. Narrow streams may be kept cool by low-growing
cottonwood, alder, and willows, without sacrificing any merchantable
timber. Wider streams will require taller trees to shade them.
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5.0 PREDICTIVE METHODOLOGY FOR NONPOINT SOURCE POLLUTION CONTROL
Management of a silvicultural system in a manner which minimizes pollu-
tion could best be effected if factors responsible for discharge of
pollutants were quantitatively related, by what might be called pollu-
tion indices to both the individual parts of the silvicultural system and
to the system as a whole. Many factors must be considered, and the
relationships are quite complex. Much additional information and data
are needed to more fully develop the relationships between pollution and
silvicultural practices.
Predictive methodology (methods, based on mathematical techniques, used
for purposes of calculating pollution as a function of conditions in
the forest) is as a consequence only available in part, and needs to be
refined. A particular need is the development of criteria for relating
quantities and concentrations of emitted pollutants that may degrade
environmental water quality.
Much effort has been devoted to analyses of soil erosion. Cropland has
been the principal concern of the studies; erosion of forest lands has
been studied to a lesser extent. Predictive methods resulting from
research and field tests still fall short of the capability to relate
water quality to conditions in a forested watershed. However, the
methods are based on consideration of the several factors which are
important in erosion and erosion prevention/control. For this reason,
it is appropriate here to present a summary description of three
methods which have much in common. The first and best known method is
the Universal Soil Loss Equation, which has been tested on forest lands.
No predictive methodology has been developed for other pollutants--such
as pesticides or fertilizers. Since soil erosion and surface water run-
off are major modes of transport of nutrients (fertilizers), pesticides,
and other pollutants to surface waters, the Universal Soil Loss Equation
is potentially useful for estimating quantities of these pollutants dis-
charged into streams and lakes; further study and development is needed,
however. The method available for predicting erosion as a function of
forestry management practices is discussed in the following paragraphs.
5.1 Prediction of Erosion by the Universal Soil Loss Equation
Three components are involved in estimating soil erosion:
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1. Soil characteristics, and topography.
2. Land cover conditions.
3. Regional rainfall characteristics.
The soil characteristics considered are credibility, the relative
susceptibility of the soil to the erosion process. Generally, the
finer textured soils—high in silts and clays, are more erodible than
the coarser textured sandy soils. Generally, steeper and longer slopes
(topography component) are more susceptible to erosion than lesser and
shorter slopes. The land cover component refers to the ability of a
cover, such as crops, grasses, and trees to absorb the impact energy
of the rainfall. Another important factor to be considered in
quantifying the soil erosion rate is rainfall characteristics. When
factors other than rainfall are held constant, the erosion rate is
directly proportional to the total kinetic energy of a storm.
The essential factors discussed above in the erosion process have been
incorporated in a "Universal Soil Loss Equation," presented by Wischmeier
and Smith, in USDA-ARS Agriculture Handbook 282.^7/ This equation was
originally developed to predict erosion from croplands, but has later
been adapted to forestry areas to predict soil sediment removal by
erosion and to better understand erosion control procedures by vegetative
cover on the land.
In silviculture, the control practice is exemplified by the use of
buffer strips between the eroding site and the nearest stream.
The use of a narrow buffer strip carries more risk than does a wide
buffer strip that sediment, carried by water, can penetrate this
vegetative filter and enter the stream or standing water body. The
Wischmeier Universal Soil Loss Equation is a mathematical tool that can
be used to estimate the width of a buffer strip necessary to protect
stream water quality from a disturbed soil area.
The results of a study by PackerM' indicate a method to evaluate the
relative vegetative trap efficiency of different types of buffer strips.
This study ws.s conducted in the Northern Rocky Mountains under certain
fixed conditions. Table 14 gives the protective strip widths necessary
to contain 83.57» of sediment flows from outlet of the logging road
drainages. The results, presented in varying obstruction spacings and
kinds of obstructions, are for conditions of 9-m (30-ft) cross-drain
spacing, zero initial obstruction distance, 100% fill slope cover density,
and 5-yr old roads built on the most stable soil that are derived from
74
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75
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basalt. It was estimated that by adding 9 m (30 ft) to the strip width
indicated in Table 14, the trap efficiency can be increased to about 97.5%.
The footnotes to Table 14 indicate the variation in protective-strip
widths from those in the table which are necessary with changes in soil,
cross-drainage spacing, initial obstruction distance, road-age, and fill
slope cover density.
Another method for evaluating soil cover efficiency in the equation in-
volves a rule-of-thumb technique which is suggested for estimating re-
quired buffer strip width, which will provide sufficient protection. For
a general situation, Trimble and Sartzfti/ suggest a 7.6-m (25-ft.) width
on level lands; and adding 0.6 m (2 ft) for each 1% increase in slope.
For areas clo«e to municipal water supply, they suggest beginning with a
15.2-m (50-ft) strip and increasing by 1.2 m (4 ft) for each 17o increase
in slope. These suggestions were made based on field measurement of the
sediment path of culverts in the White Mountains, with well-drained
sandy loam and a hardwood leaf litter of 5-10 cm (2-5in.). They emphasize
the method may or may not apply elsewhere.
5.2 Other Prediction Methods
The Universal Soil Loss Equation was developed based upon information
collected from 37 states east of the Rocky Mountains, and is being
successfully used in most areas of this region. For western states,
this equation has been used very little because adequate soil type
correlations have not been done for western soils. However, some
think that procedures developed by Musgrave^O,51/ may be modified for use in
the West. Researchers are advised to consult the listed references to
become familiar with the procedures, and also with the limitations of
prediction with the Musgrave method.
It is important to note that the quantitative procedures presented with
the Universal Equation and the Musgrave Equation are limited to the
evaluation of on-site erosion for various types of land use and dis-
turbances. For a water quality planner, however, prediction of suspended
sediment levels entering surface water is more important than prediction
of the on-site erosion. For example, the planner will need answers to
questions such as: What is the suspended sediment contributions of each
land use or disturbance within the forest? What control measures are
required to reduce the sediment contribution to the acceptable level?
To answer these questions, Dissmeyer 52,53/ nas developed a method now
called the First Approximation of Suspended Sediment (FASS) which can be
76
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used to evaluate the impact of disturbances or control practices on
suspended sediments in surface water, to identify problems, and to
evaluate alternative methods to reduce suspended sediment. In addition
to the contribution from sheet erosion, PASS also takes into account
gully erosion, as well as channel erosion, and should also be applicable
to nonforested areas such as agricultural lands, highways, and urban
areas. This method has been applied in river basin planning in the
Southeast. A detailed discussion of FASS is inappropriate here. Con-
cerned individuals are referred to two publications which present the
method in detail.52^537
5.3 Background Data and Information Needed for Planning Pollution Control
Knowledge in detail of environmental conditions which impact pollution
control is essential.
5.3.1 Meteorological factors: Rainfall, wind, and temperature play im-
portant roles in pollution control. Meteorological data for the past are
available from the National Weather Service, for specific regions of the
country, and patterns established for a region should be used as the basis
for scheduling silvicultural activities. Long- and short-term forecasts
of weather are also important. Mean climatic records are used to determine
the driest and, therefore, the best months to harvest timber, but day-to-day
weather forecasts must be used to guide harvesting operations if damage to
the soil environment is to be kept to a minimum. Harvesting equipment
operating on wet and fine textured soils causes soil compaction and ex-
cessive soil surface disturbance that are conducive to accelerated yields
of sediments. Aerial applications of fertilizers and pesticides should
be scheduled for times when wind velocity is low and wind direction is
predictable.
5.3.2 Soil and geologic surveys: The U.S. Soil Conservation Service has
the responsiblity for mapping soils on all private lands in the nation,
and works with the U.S. Forest Service and other public and private land
management agencies. The U.S. Forest Service employs soil scientists
and geologists to make soil and geologic surveys of the national forests
for use in such analyses and planning activities as location of unstable
and stable soils; suitability of soils as sources of sand, gravel, clay,
or rock; suitability for road location; subsoil and surface soil erosion
potential; drainage characteristics; compaction characteristics; potential
for forest species regeneration; windthrow hazard; and suggested cutting
and logging systems for maximum environmental protection (Snyder and
Wade),54/
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Furthermore, the soil and geologic surveys are interpreted with respect
to suitability for recreational development, permeability, consistence
(water stability), and compaction. Such hydrologic interpretations are
also made on the subjects of amounts and durations of water yield, ero-
sion hazard, and potential sediment.
The soil surveys rnadebySteinbrenner.il' for the Weyerhaeuser Company are
an example of a technique developed by the National Cooperative Soil
Survey and adapted to forestry use. Similar systems are used by forest
soil surveyors; employed by the USDA Forest Service, the states, and
private timberland owners.
The system of forest soil surveys used by Steinbrenner is interpreted
for use in these ways:
1. Land capability.
2. Forest site productivity by species.
3. Windthrow hazard.
4. Logging method suitability.
5. Priority ::or thinning.
6. Soil engineering capability.
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6.0 CRITERIA FOR POLLUTION CONTROL MANAGEMENT SYSTEMS
The overall approach to control of pollution from silviculture must con-
sider the individual pollutants, their sources, and specific methods of
control. Effective control requires, however, that a pollution control
management system be developed which encompasses all significant pollutants.
Furthermore, the pollution control management system must be matched with
watershed and regional characteristics, and should be consistent with na-
tional goals. The pollution control methods presented in Section 4.0 must
therefore, be developed and used in the framework of management systems
fitted to particular silvicultural situations.
The process of development of pollution control management systems is out-
side the scope of the present study, and is the prerogative of the local
planner in cooperation with policy-making bodies. It is appropriate, how-
ever, to enumerate the criteria which apply to development of pollution
control management systems.
A primary factor is protection of water quality. Water quality goals set
by law and transferred into policy and standards by national and local
policy bodies are a requisite for the development of pollution control man-
agement systems.
The second and third primary factors are forestland productivity and the
economics of timber production, both evaluated under constraints imposed
by the need to control pollution.
Water quality and forest productivity in combination are the two key cri-
teria for development of a pollution control management system for a pro-
ducing forest, and the economics of timber production under the constraints
of pollution control determine whether a silviculture operation is eco-
nomically competitive with like operations in other regions. In a broader
context, economics, including costs of pollution control, will determine
the competitiveness of forest products with substitute, nonwood products.
The following secondary factors are important:
The time factor: A pollution control management system must be geared to
the life cycle of the forest. Today's pollution control should make
tomorrow's pollution control easier rather than more difficult, and a low
total yield of pollution over a many year period is equally as important
as transient pollutant yields.
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The land-use factor: In some forests, timber production is the primary
objective. In others, timber yield is subsidiary to other uses. The
good pollution control management system will vary to match the use
pattern appropriate for the land.
Closely related to land-use criteria is the physical stability of the
forest system, which includes resistance to wildfire (a major destabiliz-
ing force and a significant cause of water pollution); resistance to
disease; and general resistance to land movement (creep, mud slides, and
debris slides).
A final factor, forest ecosystem stability, is closely related to land-use
and physical stability of the forest. The ecosystem is essentially speci-
fied by designation of land-use. Its stability is guaranteed by adherence
to good silvicultural procedures, including pollution control management.
The good pollution control management system therefore centers on water
quality as the primary governing factor. Timber production and timber
production economics are also primary factors; these may be affected
either negatively or positively by the need to protect water quality.
These three primary factors, together with secondary factors: time, land-
use, forest system physical stability, and forest ecos}^stem stability, are
the basis for development of pollution control management systems which meet
goals for productive and environmentally acceptable use of forest land.
Overall systems analysis of a silvicultural situation in terms of these
factors should yield rational policy and decisions about the use of spe-
cific control measures, including decisions about such troublesome ques-
tions as clearcutting, prescribed burning, and pesticide use.
Some silviculturists have integrated many technical and economic disci-
plines in intensive forest management systems. These systems emphasize
production. Commercial forests are now being classified according to
potential productivity; and on the areas with greatest potential a full
"package of practices" is being applied. For example, Staebler^H.' reports
that a high yield forestry program in the Pacific Northwest is anticipated
to double the yields over those achieved in forests with minimum practices
(protection from fire, natural regeneration, no additional management).
The doubling in yield is expected to be due to: 20% from fertilization;
30% from improved regeneration; and 50% from commercial and precommercial
thinning.
It is an established fact that a well-kept, healthy forest is highly re-
sistant to erosion and mass land movement, and transfers a high proportion
of incident rainfall to subsurface water rather than to runoff. It follows
then that intensively managed forests can be expected to be substantially
80
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better protectors of water quality than poorly managed — or naturally man-
aged—forests. The high yield forestry programs appear thus to be a sound
basis for development of a pollution-control-oriented management system.
has presented a multidisciplined approach to planning a transpor-
tation system in forests which exemplifies the basic planning method needed
for development of pollution management. The transportation system is de-
signed to serve all predicted uses of each forest unit. The uses may be
as contrasting as timber transportation, scenic viewing, skiing, hiking,
and camping. Trask suggests that the planning team may be comprised of
a logging engineer, a fisheries expert, a landscape architect, a soil
scientist, a transportation engineer, and a silviculturist. He further
adds that the team should work together to develop a management system
rather than separately as independent and uncoordinated professionals.
There is a direct correlation between effectiveness of pollution control
and the capability of personnel at the field level. As in all effective
management systems, it is essential that field personnel be competent, well
informed, and granted the authority needed to make and implement decisions
relevant to pollution control. Long-range planning of pollution control
management systems should therefore include an indepth evaluation of organi-
zational structures for management planning and also for the day-to-day ad-
ministration of forest lands.
In summary, the criteria for pollution control management include a thor-
ough analysis of several technical and economic factors and alternatives
in silvicultural management; a multidisciplined planning approach to de-
velopment of specific plans and implementation procedures; and finally,
competent administration, especially at the local level. It is essential
that silviculturist s undertake the development of pollution control man-
agement systems, and implement their use. The alternative is diversion of
productive forest to nontimber activities to ensure protection of water
quality.
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7.0 ACKNOWLEDGMENTS
This report contains an evaluation of methods to control nonpoint pollu-
tion from silviculture prepared for the Environmental Protection Agency
under Contract No. 68-01-1829. The work was performed by Midwest Re-
search Institute under the supervision of Dr. A. D. McElroy, Head, Waste
Treatment and Processes Control Section. Mr. Francis W. Bennett, and
Dr. Roy L. Donahue, Principal Investigators, authored the report with
assistance from Raymond Mischon, Dr. S. Y. Chiu and Dr. A. D. McElroy.
Grateful acknowledgment is extended to Robert E. Thronson, Project
Officer, U.S. Environmental Protection Agency, and the Working Group,
composed of representatives from many EPA Agency Offices. Acknowledgment
for critical review is also tendered to the U.S. Forest Service, state
forestry and environmental organizations, the Bureau of Land Management,
and the National Forest Products Association.
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8.0 REFERENCES
1. "One-Third of the Nation's Land," A Report to the President and to
Congress by the Public Land Law Review Commission, Washington, D.C.,
342 pages, pp. 41-65, June 1970.
2. Forest-Range Task Force, "The Nation's Range Resources—A Forest-Range
Environmental Study," USDA Forest Service, Forest Resource Report
No. 19, 147 pages.
3. "Silvicultural Systems for the Major Forest Types of the United States,"
USDA Forest Service, Agriculture Handbook No. 445, 114 pages, March
1973.
4. Archie, Steve and David M. Baumgartner, Clearcutting in the Douglas
Fir Region of the Pacific Northwest, Washington Woodland Council,
17 pages, undated.
5. Pacific Northwest Pollution Control Council, "Log Storage and Rafting
in Public Waters," Seattle, Washington, 56 pages (1971).
6. Herman, Francis R., "A Test of Skyline Cable Logging on Steep Slopes—
A Progress Report," USDA Forest Service Station Paper No. 53, 17 pages,
October 1960.
7. Gardner, R. B., F. L. Jacobsen, and W. S. Hartsog, "Balloon Logging,"
Agricultural Engineering, pp. 14-17, February 1973.
8. Binkley, Virgil W., "Helicopter Logging with the S64E Skycrane. Report
of Sale," U.S. Forest Service, 23 pages, undated (probably 1972).
9. Hendrickson, William H., "Perspective on Fire and Ecosystems in the
U.S.," in, Fire in the Environment--Symposium Proceedings, Denver,
Colorado, 151 pages, pp. 29-33, 1-5 May 1972.
10. U.S. Navy, "Slash Disposal and Direct Seeding of Douglas Fir Following
Final Harvest on Navy Lands Puget Sound Area," Donald C. Roppel,
Western Division Staff Forester; Naval Facilities Engineering Command
and Arthur K. Schick, Jr., Navy Forester, Naval Torpedo Station,
Washington State; unpublished report communicated 28 June 1973, by
letter from Roy H. Ledford, Head Forester, Department of the Navy,
Alexandria, Virginia.
11. Hartong, Allan L., "An Analysis of Retardant Use," Intermountain Forest
and Range Experiment Station, U.S. Forest Service, Research Paper INT-
103, 40 pages, August 1971.
85
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12. Blahm, Theodore H., Walter C. Marshall, and George R. Snyder, "Effect
of Chemical Fire Retardants on the Survival of Juvenile Salmonids."
National Marine Fisheries Service, Environmental Field Station,
Prescott, Oregon, 23 pages (1972).
13. Swanston, D. N., and C. T. Dyrness, "Managing Steep Land," Journal of
Forestry. 264-269, May 1973.
14. Dyrness, C. T., "Soil Surface Conditions Following Balloon Logging,"
USDA Forest Service Research Note PNW-182, 7 pages, July 1972.
15. Dyrness, C. T., "Soil Surface Condition Following Tractor and High-
Lead Logging in the Oregon Cascades," Journal of Forestry, 272-275,
April 1965.
16. Megahan, W. F., and W. J. Kidd, "Effects of Logging and Logging Roads
on Erosion and Sediment Deposition from Steep Terrain," Journal of
Forestry, 136-141, March 1972.
17. Rice, R. M., J. S. Rothacher, and W. F. Megahan, "Erosional Consequences
of Timber Harvest: An Appraisal," Proceedings of a symposium on
"Watersheds in Transition," held at Ft. Collins, Colorado, 405 pages,
pp. 321-329, 19-22 June 1972.
18. Klock, G. 0., "Helicopter Logging Reduces Soil Surface Disturbance,"
Proceedings of the 46th Annual Meeting of the Northwest Scientific
Association, Whitman College, Walla Walla, Washington, 29-31 March
1973.
19. Dyrness, C. T., "Mass Soil Movements in the H. J. Andrews Experimental
Forest," USDA Forest Service Research Paper PNW-42, 12 pages (1967).
20, Fredriksen, R. L., "Erosion and Sedimentation Following Road Construction
and Timber Harvest on Unstable Soils in Three Small Western Oregon
Watersheds," USDA Forest Service Research Paper PNW-104, 15 pages (1970)
21. Forest Service, "Timber Purchaser Road Construction Audit. A Study of
Roads Designed and Constructed for the Harvest of Timber," USDA Forest
Service, Region 6, 31 pages, January 1973. Note: "Regions" in this
section refer to the U.S. Forest Service administrative regions,
shown in Figure 8.
22. Kochenderfer, James N., "Erosion Control on Logging Roads in the
Appalachians," Northeastern Forest Experimental Station, Upper Darby,
Pennsylvania, Research Paper NE-158, 15 pages (1970).
86
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23. "Industrial Waste Guide on Logging Practices," Federal Water Pollution
Control Administration, U.S. Department of the Interior, 40 pages
(1970).
24. The three documented pictures and testimony communicated by letter .
28 June 1973 from James E. Douglas, Project Leader, USDA Forest
Service, Southeastern Forest Experimental Station, Coweeta Hydro-
logic Laboratory, Franklin, North Carolina.
25. Bolstad, Roger, "Catline Rehabilitation and Restoration," in "Fire in
the Northern Environment--A Symposium," April 13-14, 1971, University
of Alaska, College (Fairbanks), Alaska, pp. 107-116 (1971).
26. Lotspeich, Frederick B., Ernst W. Mueller, and Paul J. Frey, "Effects
of Large Scale Forest Fires on Water Quality in Interior Alaska,"
U.S. Department of the Interior,155 pages, February 1970.
27. Communication by letter dated 25 May 1973, fromCarrowT. Prout, Jr.,
Chief Forester, Soil Conservation Service, Washington, D.C. 20250
to Roy Donahue, Staff Associate, Ecology and Environment, Midwest
Research Institute, 425 Volker Boulevard, Kansas City, Missouri 64110.
28. McNutt, R. B., W. H. Kelley, C. F. Montgomery, and H. C. Buckeles, "Soil
Survey of Chilton County, Alabama," U.S. Department of Agriculture
(Soil Conservation Service and Forest Service), in cooperation with
the Alabama Agricultural Experiment Station and Alabama Department of
Agriculture and Industries, 82 pages and 47 soil maps on photo base,
pp. 44, 47-49, October 1972.
29. "Soil-Vegetation Surveys in California," Division of Forestry, Depart-
ment of Conservation, State of California, Revised, 31 pages (1969).
30. Lull, Howard W., and Kenneth G. Reinhart, "Forests and Floods in the
Eastern United States," USDA Forest Service Research Paper NE-226,
94 pages, pp. 72-73 (1972).
31. McClurkin, D. C., "Site Rehabilitation Under Planted Red Cedar and Pine,"
in, Tree Growth and Forest Soils, Proceedings, Third North American
Forest Soils Conference, North Carolina State University, pp. 339-345
(1970).
32. Ursic, S. J., "Hydrologic Effects of Prescribed Burning on Abandoned
Fields in Northern Mississippi," USDA Forest Service, Research Paper
SO-46, 20 pages (1969).
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33. Research Committee on Coal Mine Spoil Revegetaticn in Pennsylvania,
"A Guide for Revegetating Bituminous Strip-Mine Spoils in
Pennsylvania" (no publisher indicated), 46 pages (1965, revLsed
1971).
34. Wollum, A. G., "Grass Seeding as a Control for Roadbank Erosion,"
USDA Forest Service Research Note 218, 5 pages (1962).
35. Pacific Northwest Pollution Control Council, "Log Storage and Rafting
in Public Waters," Seattle, Washington, 56 pages (1971).
36. Witt, James M., and David M. Baumgartner, "A Handbook of Pesticide
Chemicals for Forest Use," Forest Pesticides and Their Safe Use.
A short course sponsored by the Extension Services of Oregon State
University, Washington State University and Region 6 of the USDA
Forest Service, 58 pages, 6-7 February 1973.
37. Benton, Howard, "The Forest Service and Herbicides," USDA Forest
Service, unnumbered (1971).
38. Schlapfer, Theodore A., "USDA Forest Service Environmental Statement,
Calendar Year 1973, Herbicide Use," Pacific Northwest Region, Olympic,
Mt. Baker, Snoqualmie, and Gifford Pinchot National Forests, paged by
sections, March 1973.
39. Schlapfer, Theodore A., "USDA Forest Service Environmental Statement,
Calendar Year 1973, Vegetation Management with Herbicides," Pacific
Northwest Region, Siskiyou, Siuslaw, and Umpqua National Forests,
paged by sections (1973).
40. Groman, William A., "Forest Fertilization: A State-of-the-Art Review
and Description of Environmental Effects," U.S. Environmental Pro-
tection Agency, EPA-R2-72-016, 57 pages (1972).
41. Sopper, W. E., "Effects of Trees and Forests in Neutralizing Wastes,"
in, Proceedings, Symposium on Trees and Forests in an Urbanizing
Environment, 18-21 August 1970, Planning and Resource Development
Series No. 17, University of Massachusetts, pp., 43-57 (1971).
42. Reinhart, Kenneth G., "Critique: Forest Fertilization Impacts on
Water and the Environment," in, Regional Forest Fertilization
Symposium, Warrensburg, New York, 22-25 August 1972, USDA Forest
Service General Technical Report NE-3, p. 243 (1973).
43. Duffy, Paul D., "Loblolly Pine Seedlings Respond to Foliar Nitrogen
Fertilization," USDA Forest Service Research Note SO-122, 4 pages
(1971).
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44. "Temperature and Aquatic Life," Technical Advisory and Investigations
Branch, Federal Water Pollution Control Administration, U. S.
Department of the Interior, 151 pages (1967).
45. Brazier, Jon Roger, "Controlling Water Temperatures with Buffer Strips,"
A thesis submitted to Oregon State University for the degree of Master
of Science, 65 pages, mimeographed, June 1973.
46. Brown, George W., Gerald W. Swank, and Jack Rothacher, "Water Tempera-
ture in the Steamboat Drainage," USDA Forest Service, Research Paper
PNW-119, 17 pages, August 1971.
47. Wischmeier, W. H., and D. D. Smith, "Predicting Rainfall - Erosion
Losses from Cropland East of Rocky Mountains," USDA-ARS Agriculture
Handbook No. 282, 47 pages (1965).
48. Packer, P. E., "Criteria for Designing and Locating Logging Roads to
Control Sediment," Forest Science. Vol. 13, p. 107 (1967).
49. Trimble, G. R., Jr., and R. S. Sartz, "How Far from a Stream Should a
Logging Road be Located," Journal of Forestry. Vol. 55, pp. 339-341
(1957).
50. Musgrave, A. W., "The Quantitative Evaluation of Factors in Water
Erosion - A First Approximation," J. of Soil and Water Conservation.
Vol. 2, pp. 133-138 (1947).
51. Anderson, D. A., "Guidelines for Computing Quantified Soil Erosion
Hazard and On-Site Soil Erosion," USDA Forest Service, Southwestern
Region (1969).
52. Dissmeyer, G. E., "Estimating the Impact of Forest Management of Water
Quality," presented at Cooperative Watershed Management Workshop,
U.S. Forest Service, Memphis, Tennessee, 4-8 October 1971.
53. Dissmeyer, G. E., "Evaluating the Impact of Individual Forest Manage-
ment Practices on Suspended Sediment," Journal of Soil and Water Con-
servation, (in press 1973).
54. Snyder, Robert V., and J. M. Wade, "Soil Resource Atlas of Maps and
Interpretive Tables," Snoqualmie National Forest, Westside Pacific
Northwest Region, USDA Forest Service (1960 and 1967).
55. Steinbrenner, E. C., "Forest Soil Survey on Weyerhaeuser Lands in the
Pacific Northwest," Weyerhaeuser Center, Centralia, Washington, 119
pages (in press, 1973).
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56. Staebler, George R., "What is Optimum Forest Management?" Abstract of
testimony before the Interim Committee on Natural Resources, Salem,
Oregon, 8 pages, 1 March 1972.
57. Trask, David B., "Transportation System Planning for Forest Resource
Management Some Aspects of Resource and Transportation Analysis,"
Technical Report ETR-770-4b, Forest Service, U.S. Department of
Agriculture, 17 pages, August 1971.
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9.0 GLOSSARY
Jammer Logging - A stationary, low-lead, mechanical winch and cable system
to pull logs over the soil surface from points on a field to a central
location during tree harvest.
Nonpoint Source Pollution - A pollutant which enters a water body from
diffuse origins on the watershed and does not result from discernible,
confined, or discrete conveyances.
Pesticides - All materials, mostly chemicals, that are used for the con-
trol of undesirable insects, diseases, vegetation, animals, or other forms
of life.
Rafting of Logs - The act of floating tied logs for transport in water.
Sediment - Water-worked fragments which have been detached, transported,
suspended, or settled in water. Fragments moved by air are excluded from
this report.
Silvicide - Chemicals to kill unwanted trees.
Silviculture (Webster) - "A phase of forestry dealing with the development
and care of forests." In this report the definition includes all activ-
ities related to trees, from seed to sawlog/pulpwood, and the harvest and
transport of the products from the forest to the first permanent road.
Skid Trails - A disturbance of the forest floor resulting from logs being
pulled over the surface.
Water Pollution - A degradation of quality of water for a specified use.
Yarding of Logs - The act of assembling logs in a specified location after
cutting for the purpose of further transport.
GOVERNMENT PRINTING OFFICE 1973-546-311/113-1-3
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