&EPA
United States
Environmental Protection
Agency
Office of
Pesticide Programs
Washington, DC 20460
Region VII
March 30-31. 1!
Pest Management in
Transition
With a Regional Focus on
the Interior West
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PEST MANAGEMENT IN TRANSITION
With a Regional Focus on the Interior West
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PEST MANAGEMENT IN TRANSITION
With a Regional Focus on the Interior West
CONFERENCE PROCEEDINGS
Pest Control Strategies Conference
Denver, Colorado
30, 31 March 1978
For
U. S. Environmental Protection Agency
Region VII Office
1860 Lincoln Street
Suite 900
Denver, Colorado 80295
Mr. Dallas Miller, Project Coordinator
and
Wright Ingraham Institute
1228 Terrance Road
Colorado Springs, CO 80904
Pieter de Jong, Project Coordinator
Conference Consultants
Robert Simpson, Colorado State University
Beatrice Willard, Colorado School of Mines
The Conference and proceedings were
funded and published by
Environmental Protection Agency
Ofice of Research and Development
and the
Office of Pesticide Programs
Washington, D.C. 20460
September 1978
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CONFERENCE CO-SPONSORS
Arkansas Valley Audubon Society, Pueblo
Denver Audubon Society
Denver Botanic Gardens
Enos Mills Group, Sierra Club, Denver
Environmental Protection Agency, Region VIM
Horticultural Advisory Council for El Paso County, Co.
Horticulture Arts Society of Colorado Springs
Ricon-Vitova Insectaries, Riverside, California
Rocky Mountain Farmers Union, Denver
Rodale Press, Inc., Emmaus, Pennsylvania
PARTICIPATING AGENCIES
Colorado Cooperative Extension Service
Colorado Department of Agriculture
Colorado State Forest Service
Forest Pest Management, Rocky Mountain Region (Forest Service, USDA)
Rocky Mountain Forest and Range Experiment Station
(Forest Service, USDA)
Science Education Administration (USDA)
U.S. Department of Fish and Wildlife (Dept. of Interior)
PROCEEDINGS PRODUCTION STAFF
Pieter de Jong, manuscript preparation
John Torborg, graphics
Catherine Ingraham, typist
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PREFACE
Pesf Management In Transition is the report of a two-day working conference entitled Pej,.
Control Strategies for the Future, held 30,31 March 1978 at the Botanic Gardens in Denver,
Colorado. These proceedings Include a diversity of perspectives offered by some of the na-
tion's leaders in alternative pest control research, representatives of regional and federal
agencies, grower organizations, industry, environmental groups, and farmers and ran*
chers.
The major aims of the conference were to examine current pest control strategies, in*
traduce new alternatives for pest control into the Interior West1, document successful in-
tegrated pest management programs from across the nation, and provide information on
alternative pest control strategies to government agencies, educators, the agricultural
community and concerned individuals.
The introduction of DDT, following World War II, signaled the beginning of the synthetic
pesticide era. The initial success of pesticides led to a widespread reliance on pesticides.
This increasing dependence on pesticides as the predominant pest control strategy has
precipitated many negative effects, i.e. increased impact on non-target species and human
health, reduction of naturally occurring biological controls, and increased resistance of
pests to pesticides.
The publication of this proceedings comes during an important time of transition to in-
tegrated management. This report combines a regional view of pest problems and current
control strategies in the Interior West with documentation of the economic and en-
vironmental soundness of integrated pest management programs from across the nation.
The efforts and cooperation of many individuals, agencies and organizations have con-
tributed to these proceedings. The co-sponsors guaranteed a diverse and receptive au-
dience and the participating agencies sent representatives who aided discussions on
regional pest problems and control tactics. Kenneth Hood and Charles Reese of the En-
vioronmental Protection Agency in Washington, D.C. and Dallas Miller, EPA Region VIII,
provided assistance in developing the program. Finally, the use of the Denver Botanic
Gardens, made possible by William Gambill, was particularly appreciated as it provided a
handsome and appropriate setting for the conference.
P.dJ.
Colorado Springs
September 1978
'Interior West defined as EPA Region VIII which includes Colorado, Utah, Montana, Wyom-
ing, North and South Dakota.
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CONTENTS
Preface
Contents
Introduction to Conference
Elizabeth Wright Ingraham
Page
PART ONE OVERVIEW
Current Practices in Insect Pest Control
David Pimentel
Introduction
Biological and Cultural Controls
Chemical Pest Control
Environmental and Social Costs of Pesticides
Discussion
PART TWO PEST MANAGEMENT IN THE INTERIOR WEST
Introduction 21
Regional Pest Problems 22
Crop Pests
Noxious Weeds
Urban Pests •
Range Pests
Forest Pests
Views on Pest Management 28
Glen Murray, farmer
Thomas Lasater, rancher
Pauline Plaza, National Audubon Society
Wayne Bain, Executive Secretary, Mesa County Peach
Administrative Committee
Alan Jones, fruit grower
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Regional Programs in Integrated Pest Management
Biological Control Programs of the Colorado Department of Agriculture 37
Albert Merlino
Integrated Pest Management in Alfalfa 40
Donald W. Davis
The Need for 1PM Research in Range 43
8. Austin Haws
PART THREE CONTROL STRATEGIES
Biological Control By Natural Enemies 49
Robert van den Bosch
Naturally Occuring Biological Control
Classic Natural Enemy Introduction
Biological Control of Weeds
Preservation and Augmentation of Natural Enemies
The Future of Biological Control
Discussion
Cultural Control 59
Theo Watson
Introduction
Crop Management
Soil Management
Water Management
Integration of Cultural Practices to
Enhance Pest Management
Pheromones as Third Generation Pesticides 71
Everitt R. Mitchell /
Disruption of Mating
Pheromone Traps
Formulation
Summary
Breeding Insect Resistance in Plants: A Caa« study of Wheat and Hessian Fly 81
R. L Gallun
Early Control Tactics
Modern Breeding Programs
Summary
The Role of Chemicals In integrated Pest Management 91
8. G. Tweedy
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Introduction
Cost/Benefits of Chemicals
Industry View on IPM
Discussion
PART FOUR IMPLEMENTATION
Implementation of Integrated Pest Management Programs 97
Leon Moore
Introduction
Basic Elements of Insect Pest Management
Practical Components of Insect Pest Management
Example of an Insect Pest Management Program: Cotton in Arizona
Economics of Pest Management 105
Raymond Frisbie
Cotton IPM Programs
Summary
Discussion
Emerging Federal Policies on Pesticides 109
Charles Reese
Historical Perspective
Federal Agency Activities in IPM
Summary
Discussion
USD A Perspectives on Pest Management 117
Richard L Ridgway
Mission
History
USDA Role in IPM
Discussion
Making the Transition to an Urban IPM Program 121
Helga and William Olkowski
The Urban Condition
The Components of an Urban IPM Program
Sequence for Establishing an IPM Program
Discussion
Current and Future Research Needs 129
Kenneth Hood
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Introduction
Insect Control
Weed Control
Urban Integrated Pest Management
Future Research Needs
Agenda 133
Conference Participants 135
Index 139
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TO CONFERENCE
Elizabeth Wright Ingraham
President
Wright-Ingraham Institute
Colorado Springs, Colorado
On behalf of the Wright-Ingraham Institute and the Environmental
Protection Agency, Mr. Lehr and I would like to welcome you to this
Pest Control Strategies Conference. In introducing this conference,
I thought you might be interested in knowing how we got started on
the idea of integrated pest management. The Institute has been pri-
marily interested in tackling ideas and issues at the interface of
humans and the environment. We have tried during the early years of
this new institution to look down the road to what may be important.
Last September, Fieter de Jong, a member of our administrative staff,
with whom most of you are familiar, came to the planning council of
the Institute and said he wanted to promote integrated pest management
in the region. We talked with a few people in agencies and organi-
zations. One person retorted with, "Well, it's something of an esoteric
idea." At this point we wondered what was so esoteric about an idea
that affects, really deeply affects, food, timber and fiber production,
and an idea that involves both the rural and urban communities? One
difficulty, perhaps, was the newness of the integrated approach to
pest control so, we explored further and found the idea rising very fast
around the country. Our survey discovered, however, that no conferences
had yet been held in the Interior West. We gave the go-ahead to Pieter
who has.put together what I think is an absolutely outstanding two-day
conference on this subject.
What all of us get out of it, how the proceedings come out and what
the final analysis is, cannot be predicted. In reviewing the develop-
ment of any new idea, I think it's important to recognize that ideas are
a process. Many of us working on new ideas want them to move forward
immediately, but of course this doesn't often happen. New ideas have
Co percolate through the system and find conduits for implementation.
We first have to expand the body of thought, which we are doing at this
conference. Then we have to take that thought and put it into demon-
stration and experimental models, prototypes and pilot projects. After
this the projects have to assessed and evaluated. That's a difficult
area because there the idea, as policy, must be reviewed by the political
forces before it becomes part of the system.
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Although components of integrated pest management (IFM) are as old as
the invention of agriculture, the concept of IFM is really very new.
It was not until the mid-60's that the term was coined. -In 1972, the
Council on Environmental Quality put out its publication on IPM and
while scientists had been working on the idea for many long years, it
was now at the frontier of what we call the lead time for implementing
an idea.
This important concept of IPM is closely tied and related, I think,
to the rising interest in food production and environmental problems
and the entire idea of food production to meet the demands of Increased
population. In 1975, when the Institute published a report on food
production for the lettering Foundation, this issue of pest management
was raised. Pest control for crops was one of the key issues involved
in considering global food production in the next 25 years. The issue
is even more critical today. The Institute will continue to explore
and expand on these integrated approaches which are necessary for a
dynamic system. Out of this conference we hope to capture ideas on
where we've been, where we're going, and what needs to be done to Imple-
ment this new direction in pest control and management.
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Part One
Overview
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CURRENT PRACTICES IN INSECT PEST CONTROL
David Pimental and Nancy Goodman
Department of Entomology
Cornell University, Ithaca, New York
INTRODUCTION
All crops and livestock are attacked by pests. Worldwide man loses
nearly half of his food to pests. World crop losses to pests (insects,
pathogens, weeds, mammals, and birds) are estimated to be about 352
(Cramer, 1967). Mammal and bird losses appear to be more severe in
the tropics and subtropics than in the temperate region, but these
losses are low compared with losses to the three major pest groups of
insects, pathogens, and weeds.
In addition to the 35% preharvest loss an estimated 20% postharvest
loss results from another group of pests, primarily microorganisms,
insects, and rodents. When postharvest losses are added to preharvest
losses, worldwide food losses to pests are estimated to be about 48%
(35Z preharvest plus 20% postharvest losses).
In the United States preharvest losses to pests are estimated to be
about 33% in spite of modern pest control technology (USDA 1965; Pimentel
(1976). This loss is not much below the estimate of the worldwide loss
of 35%. However, postharvest pest losses are about one half of the
worldwide level (20%) or only 9% (USDA 1965). Thus, total losses in the
United States are about 39%. This is a significant loss of valuable
food. As mentioned, these losses occur in spite of all pest management
efforts.
It is worthwhile to explain the term pest management and its relationship
to integrated pest management (IPM). Pest management is the general term
that includes all biological, cultural, and chemical programs employed
for pest control. Integrated pest management employs a combination of
biological and pescicidal controls. This is the way IPM was first de-
fined and continues to be used today (R. Smith, University of California,
personal communication 1977).
The aim of this paper will be to examine the current use of biological,
cultural, and pesticidal controls in pest management in the United States.
In addition, we will briefly examine the environmental and social costs of
pesticide use.
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BIOLOGICAL AND CULTURAL CONTROLS
Although pesticides are often considered to be the nest important control
technology for pests, biological and cultural controls in fact are more
important than pesticides when a comparison is based on managed acres.
For example, biological and cultural controls are employed on 9% of farm
acreage compared with insecticidal controls that are employed on only 6Z
of .the acres (Table 1). For the control of plant pathogens, some form
of biological and cultural control is employed on more than 95Z of the
acreage compared with less than 12 on which fungicides are used. For weed
control, the estimate is that nonchemical controls, primarily mechanical
cultivation, are used on 80% of the acreage while only 17% are treated
with herbicides (Table 1).
At this stage it would be profitable to examine some of the biological
and cultural methods that are used to control pest insects, pathogens, and
weeds.
P«re«ne«g« of Acrm Involv«d
Biological and Cultural PMticldal
P««ea Controls Controls
Xaaactft 92 6Z
Pachogwu 902 12
VMda 80Z 17S
Table 1 Comparison of estimated biological and cultural and
pesticidal controls employed on the United States Crop-
i land for insects, pathogens and weeds (USDA, 196S; 1970;
PSAC, 1965; Pimsntel, 1976).
Host Plant and Animal Resistance
One of the most important reasons for serious pest problems on crops is
the breeding of susceptible types (Lupton, 1977). When altering the
genetic makeup of the crop plant to increase yields, in the past little
or no attention was given to maintaining the natural resistance to pest
attack that existed in the crop. Natural resistance can be lost or greatly
reduced if care if not taken to maintain it. Of importance then is breed-
ing plants that not only have high yields but are resistant to their major
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pests. Plant breeders have maintained the level of resistance to plant
pathogens and are now giving vigorous attention to insect resistance in
crops.
The differences in levels of resistance that may exist in crop plants
and their effectiveness are well illustrated with pea aphids (Aaryrthcsiphim
pi sum) associated with alfalfa (Mediaago sativa). Five young pea aphids
placed on a common crop variety of alfalfa produced a total of 290 off-
spring in ten days, whereas the same number of aphids for a similar period
on a resistant variety of alfalfa produced a total of only two offspring
per aphid (Dahms and Painter 1940). Obviously, a pest population with
a 145-fold greater rate of increase on a host plant would inflict greater
damage on the host plant than one with an extremely low rate of increase.
Sorghum provides another example. On a susceptible 'strain of commercial
sorghum (Sorghum vulgare) the mean rate of oviposition (eggs per genera-
tion) of the chinch bug (Bliasus leucopterua) was about 100. On a
resistant strain of sorghum, however, the mean oviposition was less than
one (Dahms 1943). In this instance, animal feeding was reduced by 99%
on the resistant plants and had dramatic effects on the population dyna-
mics of the feeding pests.
The Hessian fly (Moyetiolo. destructor'), a serious pest of wheat, is
effectively controlled on at least a third of Hessian fly infested acreage
(20 million acres) by Hessian fly resistant varieties (PSCA 1965). Some
biotypes of the Hessian fly have evolved that are able to overcome the
resistance present in the wheat but new resistant varieties are being
released.
Natural resistance to pests also exists in livestock. For example,
European cattle introduced into South Africa were found to be more sus-
ceptible to the "bont" tick (Amblyorma hebraeum) and to "heartwater"
disease than Afrikander (zebu) cattle (Bonsma 1944). The number of ticks
on the European cattle were about four times more abundant than on the
native Afrikander (table 2), The mortality in Afrikander cattle due to
Total* for 12 eow« of R*cio
««ch kind Europ«*a:
AfrikanderEurop««n Afrikande
Huob«r of eicfca;
12 count* p«r cow:
On th« body (800 en2) 237 1,773 7.5:1
On th« ««cuech«on COO em2) 1,329 4,397 2.9:1
0>.d« eh. tall 2,140 4,789 2.2:1
Table 2 The toinber of ticks on Afrikander and European cattle
(Bonsma 1944).
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heartwater disease averaged only 5.3% over I thirty-month period whereas
for European cattla the average was 60.7% tejrtality. Thus, the European
cattle that had never been eseposed to eithei the tick or heartwater
disease were highly susceptible to the attack of boch pests.
%
Rotations
In agriculture, when crops and livestock are maintained on the same
land year after year, pests associated with the crops or livestock tend
to increase in number and severity. For example, if cole, crops are
cultured for several years in the same soil, club root (Plasmodiophora
bra8$i.cas} organisms increase rapidly and can totally ruin production
(Walker at al. 1958). Planting noncole crops on the land for several
years will effectively control these pests.
Also, if soybeans are grown on some land more than once every three to
four years, brown stem rot (Cephalospovius gvegatw) may be a serious
problem (Carter and Hartwig.1963). In the U.S. corn belt, corn and
small grains make good rotation crops and reduce problems from the brown
stem rot in soybeans.
Rotating corn with soybeans also helps control the most serious insect
pest of corn, corn rootworms (G. Musick and R. Treece 1975, personal
communication). Corn must be rotated every year to provide effective
control of rootworms, and this rotation combines nicely with soybeans
and small grains. Corn rootworms are controlled successfully in about
602 of U.S. corn acreage by employing crop rotations (Pimentel et al.
1978a).
Cropping Systems
Although they may prefer one crop, some pests can feed on several crops.
In addition, certain parasites and predators can attack a pest and re-
lated pests on different crops. Because the parasites and predators .can
move from one crop to another searching out suitable pest hosts, they
can control pest populations. The technique requires planting suitable
crops in combination. For example, plant bugs (Lygus spp.) feed on
alfalfa and cotton. After alfalfa is mowed for hay and eliminated as
a food source for the bugs, they will move to cotton in large numbers
(Stern 1969). Th®r«afters the bugs can damage cotton if present in
sufficient numbers. Because the plant bugs generally prefer alfalfa,
the Lygus bug population on cotton can be kept to a minimum by planned
cutting of the alfalfa. The successful strategy is to cut only a portion
of the alfalfa at a time leaving sufficient alfalfa to attract the bugs
and keep them away from the cotton. Another strategy is to plant narrow
strips of alfalfa (6 m wide) for every 91-122m of cotton in the cotton
field. This not only attracts the plant bugs but may provide a source
of natural enemies of such pests as cotton bollworms.
Also combining sorghum and cotton has demonstrated that several pests of
cotton can be effectively reduced and the number of pesticide treatments
significantly reduced (Ray Frisbie, Texas A&M; Don Peters, Oklahoma State
Univ., personal communications 1975).
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The leaf miner problem associated with spinach in California was in part
solved by planting spinach considerably after the other crops that usually
harbored the leaf miner (H. Lange, personal communication 1974). With-
out a suitable host, the leaf miner population was reduced significantly
before the spinach was planted. Another way to control such a pest is
to reduce the growing of crops that act as an alternate host.
Genetic Diversity
Numerous examples make it clear that many parasites have the genetic
variability to evolve and overcome "single-factor" resistance in their
host. Hence, although parasites associated with hosts in natural situa-
tions appear to be genetically stable, in agricultural ecosystems when
stressed by a single factor, a parasite can often evolve, overcome host
resistance, and cause serious, damage to crops. For example, parasitic
stem rust and crown rust have been found to overcome genetic resistance
bred into their oat host. Since 1940, oat varieties have been changed
in the corn belt region every four to five years to counter the changes
in the races of stem rust and corn rust (Stevens and Scott 1950, van
der Plank 1968).
Recently the Southern corn leaf blight parasite overcame resistance in
corn (Thurston 1973). The use of Texas sources of cytoplasmically in-
herited male sterility (TMS) narrowed the resistance character in about
85% of the corn grown in the United States to almost genetic homogeneity
(Moore 1970; Roane 1973). Then in 1970, favorable environmental con-
ditions resulted in selecting race T of Sebrtinthosporiim maydis (Southern
corn leaf blight), which is virulent on all plants with TMS cytoplasm.
The resulting epidemic caused devastating losses in the genetically homo-
geneous corn host (Nelson et al. 1970).
Genetic diversity within a given crop, however, prevents a pest from
overcoming natural plant resistance (Wolfe 1968). For example, when the
wheat variety Eureka, resistant to wheat stem rust races, was grown in
progressively larger acreages, the incidence of the rust races attacking
Eureka also increased (Fig. 1). The prime reason for the increase was
that with the greater distribution of the Eureka variety, rust races
could now be more easily transmitted from host to host. When the abun-
dance and distribution of Eureka wheat declined, the incidence of rust
infections by the special rust race also declined (Fig. 1). This example
of a pathogen-wheat host system clearly illustrates the benefits of
genetic diversity in agricultural crops.
Pest outbreaks occurring in "green revolution" wheat and rice varieties
have been associated with planting a single variety over wide regions
(Frankel 1971; Ida Oka 1973, personal communication). The need for
genetic diversity of resistant characters in host-plants for both "green
revolution" and U.S. monocultures has been well documented by Pathak
(1970), Adams et al. (1971), Smith (1971), and Day (1973).
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20
10
ta
oa
52
Eureka wheat
80
40
1939
1947
1955
1963
Figure 1 The percentage of acres of Eureka wheat ( ) grown
in northern New South Wales of total wheat acres and
the percentage of wheat stem rust races which are able
to attack Eureka coopared with all races present (——).
(Data of Watson and Lugig, 1963)
Planting Times
Some plants in nature begin to grow early or late in the growing season
and thereby manage co escape the attack of certain pests. Wild radishes
have been observed to germinate early in the spring and make most of their
growth before the cabbage maggot fly emerges and attacks the radishes.
Damage to the radishes under these conditions is usually minimal (Pimentel,
unpublished).
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Other plants may escape attack by starting growth after the pest popula-
tion has emerged and begun to die. This strategy has been employed by
agriculturalists to reduce the attack on wheat by the Hessian fly. De-
laying the seeding of wheat fields is effective on about 67% of the
wheat acreage in reducing the attack from the dangerous fall brood of
the Hessian fly (PSAC 1965). The spring brood of the Hessian fly is less
serious and delayed planting does not reduce the spring brood attack.
Growth stage may be an important factor in vulnerability to attack. Corn,
for example, is more susceptible to corn borer attack at certain stages
of growth. Young corn (15.2 cm high) is relatively unattractive to corn
borers compared with corn that has reached 45.7 cm high (Whitman 1975).
If a farmer wants to reduce corn borer attack, corn should be planted
so that plants are either very small or nearly full grown before the
borer moths emerge.
Introduced Natural Enemies
Biological control utilizing introduced parasites and predators has
proved highly effective in controlling certain insect pests. For example,
both the spotted alfalfa aphid and alfalfa weevil are major pests of
alfalfa. Of the 29 million acres of alfalfa grown in the United States,
about 9 million are infested with the spotted alfalfa aphid. Control of
this pest is achieved primarily by natural enemies and by the planting
of alfalfa varieties resistant to the aphid (PSAC 1965). Although nearly
half of the alfalfa crop is attacked by the alfalfa weevil, this pest
is now generally controlled by natural enemies and alfalfa culture
practices.
Citrus and olive crops on about 3 million acres have several insect pests
that are effectively controlled by natural enemies (Sweetman 1958, van
den Bosch and Messenger 1973). Control of a few of the citrus insect
pests is achieved on most of the citrus acreage whereas control of the
olive insect pests is generally effective on all acreage.
CHEMICAL PEST CCNTRQL'
Various chemical methods including olfactory attractants, juvenile hor-
mones, and especially pesticides are employed for control of insects,
pathogens, and weeds. The extent of the use of these controls is dis-
cussed.
Olfactory Attractants
Insect behavior is governed by various stimuli including chemicals re-
leased by some insect species themselves. These stimuli play important
roles in guiding insect feeding, mating, and oviposition.
Feeding, mating, and oviposition are all essential behavioral patterns
for insects. If the pattern is altered by changing the normal stimuli
that che animal receives, survival and reproduction may be significantly
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reduced. The use of olfactory attractants is aimed at changing th«
normal stimuli received by insects to limit the increase of insect
populations (Birch 1974; Roelofs 1975).
These attractants can be used to monitor insect populations by baiting
traps to determine when to treat an insect population with an insecticide.
Most agree that one of the extremely difficult tasks in economic ento-
mology is to measure insect pest densities accurately to determine when
to treat with an insecticide (PSAC 1965). The use of attractants for
monitoring offers unique opportunities to improve the measurement of
insect population densities. "
Attractants have already been employed effectively to eradicate a
serious pest, the Mediterranean fruit fly (Ceratitua capitate) from
Florida in 1956 (Metcalf et al. 1962). In this case an attractant,
protein hydrolysate bait containing malathion, was distributed through-
out the area of fruit fly infestation (PSAC 1965). The use of the
attractant made it possible to bring the flies directly in contact with
an extremely small amount of the insecticide. This was the first actual
eradication of a pest in the United States.
Chemical attractants can also be employed for baiting "sticky" traps
to capture, for example, pest moths. On an experimental basis,
Roelofs et al. (1970), controlled the redbanded leaf-roller (Argyro-
taenia velutinana). from New York apple orchards by attaching a sticky
trap to apple trees and baiting it with a female sex attractant. When
about 100 traps per hectare were used, effective control was achieved
without insecticide use.
Another technique employing a sex attractant that offers potential is
the use of the attractant to "disrupt" normal mating of the pest popula-
tion. For insect pests that totally depend upon a chemical sex attractant
for mating, it may be possible to release sufficient quantities of the
attractant to "disrupt" the mating of the population.
This procedure has several advantages. First, the technique is specific
for a particular pest, avoiding the difficulties of the use of broad
spectrum insecticides. Second, often the amount of chemical introduced
into the environment is extremely small (as low as 3 grams per hectare
per season)(W. Roelofs, Cornell University, personal communication 1976).
Third, since all the sex attractants known are nontoxic to humans and most
other life, the impact on the environment should be minimal.
Attempts to employ sex attractants against the introduced gypsy moth
(Porthetria diepar') have had some success experimentally (Beroza et al.
1973). Application from 2 to 5 g per hectare of encapsulated pheromone
(disparlure) reduced gypsy moth males by. 902 or more for 6 to 8 weeks.
In another study, Shorey and co-workers (Birch 1974; Farkas et al. 1975)
have experimentally demonstrated that releasing about 25 mg/ha/10-hr
night of the pheromone, cr£e-7-dodecenyl acetate, could disrupt about 95%
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of the cabbage looper (Trichoplus-ia ni) population. The actual amount
of pheromone necessary for release to disrupt a population depends on the
species and environmental conditions. For example, under windy conditions
considerably more pheromone would have to be used.
The potential advantages of attractants have been mentioned, but the
technique also has limitations. One of the most important limitations,
which is also experienced with insecticides, is the evolution of "resis-
tance" or "tolerance" in insect populations to attractants.
Although some insect species depend entirely upon sex attractants for
mating, a "dosage response" does exist in their reaction to the attractant
stimuli. Recall earlier that 90% of the gypsy moth population and 95%
of the cabbage looper population were disrupted by the released sex
attractant. The 5 to 102 of these populations that were not responding
probably require a higher dosage or other stimuli. If some of the 5 to
10% are able to mate in spite of the disruption, then natural selection
is operating and the populations should eventually evolve tolerance.
In fact, populations of the cabbage looper have evolved tolerance and
are able to carry out normal mating in spite of the release of a sex
attractant (H.H. Shorey, University of California, Riverside, personal
communication 1976).
Pesticide Use and Controls
The use of pesticides more than doubled during the 10 year period from
1966 to 1976; pesticide use on crops and livestock increased from 503
million pounds to over 1 billion pounds (Berry 1978).
Pesticide use in agriculture is not evenly distributed (Table 3). For
example, 50% of all insecticide used in agriculture is applied to the
nonfood crops of cotton and tobacco. Of the food crops, fruit, and vege-
tables receive the largest amounts of insecticide. Of the herbicidal
material applied, 45% is used on corn, with the remaining 55% distributed
among numerous other crops (Table 3). Most of the fungicidal material
is applied on fruit and vegetables, with only a small amount used on
field crops (Table 3).
Benefits of Pesticides
Pesticides are essential to U.S. agricultural production; however, in
spice of more than 1 billion pounds of pesticides used in agriculture,
an e.stimatad 33% of all crops is lost annually due to pest attack in the
United States. This loss of food and fiber amounts to about $35 billion,
or enough to pay for our 1976 oil imports.
We have examined the frequently asked question, what would our crop losses
to pp.st.•? be if all pesticides were withdrawn from use, and readily available
noncuemiciil control methods were substituted where possible? It appears
that crop losses based on dollar value would increase from the estimated
33% to about 41% (Pimentel et al 1978b). Thus we estimated an 8% in-
:re.Ti. >n crcj I,.-i ,&s worth $8.7 billion could be anticipated if pesticides
were withdrawn from use.
-------
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?Mtur* IUf
4 UM*
v«t«t«bl*
FotMOM
frolt
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All grout
HA •*•» not «v
I
-------
Crop losses without pesticides were also evaluated based on food and
feed energy, expressed as kilocalories (kcal). Losses to insects,
diseases, and weeds in crops grown without pesticides but using some
alternative controls were estimated to increase only 1% (Pimentel et
al. 1978b). When nonfood crops were excluded, the increased loss of
crops grown without pesticides was only 4% in food calories.
Based on these estimates of increased food energy losses, 1% for total
crops or 4% for food crops, there would be no serious food shortages in
the United States if crops were not treated with pesticides. Although
the supply of food in the nation would be ample, the quantities of
certain fruits and vegetables, such as apples, peaches, plums, onions,
tomatoes, peanuts, and certain other crops would be significantly reduced.
Because of this, some fruits and vegetables that we are accustomed to
eating would have to be replaced with others.
Although our food-energy supply would be little affected by the withdrawal
of pesticide use, the dollar loss to the nation would be considerable.
This would amount to an estimated $8.7 billion loss, including added costs
of employing alternative nonchemical controls that would be used if pesti-
cide use were withdrawn (Pimentel et al., 1978b). Considering that
current pesticide treatment costs, material and application, are esti-
mated to be $2.2 billion annually, the return per dollar invested in
pesticide control is about $4. This agrees well with previous calcula-
tions of between $3'and $5 and adds credibility to our analysis of esti-
mated crop losses if pesticides were withdrawn.
ENVIEDNMENTAL AND SOCIAL COSTS OF PESTICIDE USE
In calculating the benefits of pesticides at $4 per dollar invested in
control, Pimentel et al., (1978b) did not include a dollar value for
the "external costs" of human poisonings and the impact of pesticides
on the environment. To evaluate the external costs of pesticide use,
the relationship we have with our environment must be understood.
Although everyone knows why food is essential, not everyone is aware of
why the environment is equally essential to us. We cannot maintain our
high standards of health and achieve a quality life in an environment
consisting only of our crop plants and livestock. Most of the estimated
200,000 species of plants and animals in the United States are an integral
and functioning part of our ecosystem. Many of these species help renew
atmospheric oxygen. Some prevent us from being buried by human and
agricultural wastes and others help purify our water. Trees and other
vegetation help maintain desirable climate patterns. Some insects are
essential in pollinating forage, fruit, and vegetable crops for high
yields. No one knows how much the population numbers of these 200,000
species could be reduced or how many species could be eliminated before
agricultural production and public health would be threatened.
11
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The impact of pesticides on agriculture, the environment, and public
health is significant. There are a calculated 109,000 accidental human
pesticide poisonings annually in the United States (Pimentel et al.
1978c). An estimated 6,000 individuals are hospitalized (EPA 1974)
and associated with the poisonings an estimated 200 fatalities occur
annually (EPA 1974). Apparently none: of the poisonings and fatalities
were due to eating food crops that were treated properly with pesticides.
The people especially prone to pesticide poisoning are pesticide pro-
duction workers, farm field workers and pesticide applicators. Of the
field workers and pesticide applicators in the United States, an estimated
2,826 were hospitalized in 1973 because of pesticide poisoning (Savage
et al. 1976).
Because of their widespread use, pesticides are consumed by people, In
fact, in one study from 932 to 1002 of the people surveyed tested positive
for one or more pesticides (EPA 1976). Annual studies conducted by the
FDA determine the kinds and amounts of insecticide residues in typical
human daily diets. The residues of DDT and its metabolites in foods
generally have been low (952 below 0.51 ppm). The incidence of contamina-
tion, however, was high, i.e., about 502 of the food samples contained
minute but detectable insecticide residues (Duggan and Duggan 1973).
Residues of the phosphate and carbamate insecticides are generally less
persistent than are the chlorinated insecticides. The FDA data suggest,
however, that residues of phosphate and carbamate insecticides are be-
ginning to increase in raw products, and therefore also in the total diet.
This increase was to be expected after DDT was banned by the EPA in 19-2.
In addition, the public will continue to be exposed to residues of DDT
and other chlorinated pesticides because these persist in the environment.
At present, overall pesticide residue levels appear to be sufficiently
low to present little or no danger to human health in the short term.
Samples of fruits and vegetables rarely have insecticide residues that
exceed 2 ppm (Duggan and Duggan 1973; FDA 1975). For example, of 1,551
samples of "large fruit" only 10 showed residues of 2.8 to 13.5 ppm.
Residues ranging from 2.3 to 84.0 ppm were detected in 97 out of 2,461
leafy and stem vegetable samples. Unfortunately, little is known about
the effects long-term, low-level dosages of pesticides may have on public
health (HEW 1969). Furthermore, the possible interaction between low-
level dosages of pesticides and the numerous drugs and food additives
the public consumes has not been completely studied.
The ecological effects of pesticides on nontarget species are varied
and complex (Pimentel and Goodman 1974; Edwards 1973). For example,
some pesticides have influenced the structure and function of ecosystems,
reduced species population numbers in certain regions, or altered the
natural habitat under some conditions. Some have changed the normal
behavioral patterns in animals, stimulated or suppressed growth in
animals and plants, or modified the reproductive capacity of animals.
In addition some have altered the nutritional content of foods, in-
creased the susceptibility of certain plants and animals to diseases and
12
-------
predators, or changed the natural evolution of species populations in
some regions. Because of this great variation in effect, it is necessary
to study the impact of individual pesticides to obtain a fair and
balanced picture.
Another interesting aspect of the pesticide problem is the fact that
the more than 1 billion pounds of pesticide applied in the United States
are. used to control only about 2,000 pest species. If these pesticides
reached only the target species, pollution would not be a concern. Un-
fortunately however, only about 1% of the pesticide used ever hits
the target pests (PSAC 1965). Often as little as 25% to 50% of the
pesticide formulation reaches the crop area, especially when pesticides
are applied by aircraft (Hindis et al 1966; Ware et al. 1970; Buroyne
and Akesson 1973), Considering that about 65% of all agricultural in-
secticides are applied by aircraft, the risk both to the environment
and to public health is great.
Pesticides are potent biocidas and in some cases they may adversely affect
the physiology of crop plants. Any change in the physiology of a crop
plant can either make the plant more resistant or more susceptible to
attack by its parasite and predators. Since crop plants that are not
physiologically stressed can more eaily resist parasite and predator
attack, any chemical that alters normal physiology is likely to incrnase
the susceptibility of the crop plant. This was demonstrated when caJ cium
arsenate was used on cotton. McGarr (1942) reported that aphids on ui-
treated cotton plants averaged 0.91 per 6 cm^ of leaf area whereas aphids
numbered 6.05 on plants treated with calcium arsenate (about 6.7 kg/ha).
Herbicides have also been found to increase insect pest and pathogen
problems associated with corn. For example when corn plots were treated
with a regular dosage of 0.55 kg, 2,4-D/ha, aphid numbers on the corn
averaged 1,679 whereas on the untreated they averaged only 618 (Oka and
Pimentel 1976). Corn borer infestation averaged 28% in the 2,4-D treated
corn population compared with only 16% in the untreated corn population.
In laboratory investigations of the impact of 2,4-D on the relative re-
sistance of corn plants to pathogens, exposed corn plants were signifi-
cantly more susceptible to corn smut disease (Ustilago maj/
-------
pesticide poisonings; costs of several thousand days of work lost b«-
cause of pesticide poisonings; and additional medical costs for about
100,000 human pesticide poisonings treated as outpatients. Other
environmental and social costs included were: several million dollars
in direct honey bee losses; reduced fruit crops and reduced pollination
from the destruction of wild bees and honey bees; livestock losses; commercial
and sports fish losses; bird and mammal losses; natural enemies of pests
destroyed, resulting in outbreaks of other pests; pest problems that re-
sult from pesticide effects on the physiology of crop plants; and increased
pesticide resistance in pest populations. All of these contribute to
the "external costs" of pesticides and must be considered in any cost/
benefit analysis.
DISCUSSION
QUESTION^ What is your view on drift problems associated with aerial
application?
PIMEHTEL: There ia no better means for distributing pesticides in the
environment than using aircraft. Now I am not saying that you should
not use aircraft; there are many areas where you have to use aircraft.
When cotton is mature or when corn is very high, you have to use air-
craft, What I cm pleading for is that we have to improve the methods
of application so that we reduce the drift problem that does occur with
aircraft applications and also discourage the use of aircraft applica-
tions when they are not necessary.
QUESTION: Isn't a helicopter application much more efficient than aircraft?
PB4ENTEL: No. The main problem is that when you try to put that material
in small droplets, it disperses into the atmosphere and then you have
problems. It is a little bit more efficient, but not that much.
QUESTION: I realize that we are concentrating on the United States here
but I wonder if you have any current figures on China's use of pesticides
and their effects on predators and crop losses.
PIMENTEL: les, China is using large quantities of pesticides and they
are having same problems associated with the use of pesticides, as are
other,.nations. In other words, in the United States you hear complaints
about all our regulations, but go overseas, into Central America and
parts of India, where there are no regulations and see the real problems
related to the use of these pesticides. It makes you appreciate our
regulations.
14
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QUESTION: I have always felt that plant resistance is one cf the
•important resistances a plant had. Sou do you see this strategy
being approached?
PXMEHTEL: les, that is true and they are really going to work on
it now. But another point to remember is that the plant "breeders
came in to deal with insect control when all else failed. There
were no insecticides available. Wheat and the Session Ply is one
example, and, to a degree, corn borer; it was not that effective.
This was when our colleagues in plant breeding came to our rescue.
This has been true about past efforts in breeding plant resistance
and I am glad plant breeders are working in this area now. But if
you look at diseases, where they did not have the type of control
that we have in entomology, they have been highly successful. I
would say 95% of our crops have some degree of resistance to plant
pathogens and congratulations to our plant breeders.
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uniformity and disease epidemics. Bio. Sci. 21)1067-1070.
Beroza, M., L.J. Scevens, B.A. Bierl, P.M. Philips and J.G.R, Tardif.
1973. Pre- and postseason field tests with disparlure, the
sex pheromone of the gypsy moth, to prevent mating. Environ.
Entomol. 2:1051-1057.
Berry, J.H. 1978. Pesticides and .energy utilization. Paper pre-
sented at AAAS Ann. Mt., Washington, D.C. February 17.
Birch, M.C. (ed.) 1974. Pheromones. North-Holland Pufal. Co.,
Amsterdam. 495 pp.
Bonsma, J.C. 1944. Hereditary heartwater-resistant characters in
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Buroyne, W.E. and N.B. Akesson. 1971. The aircraft as a tool in
large-scale vector control programs. Agr. Aviat. 13:12-23.
Cartter, J.L. and E.E. Hartwig. 1963. The management of soybeans.
pp. 162-226 in The Soybean:: Genetics, Breeding, Physiology,
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Cramer, H.H. 1967. Plant protection and world crop production.
Pflazenschutznachrichten. 20(I):1-524.
Dahms, R.G. 1948. Effect of different varieties and ages of
sorghum on the biology of the chinch bug. -J. Agr. Res. 76(12):271-238.
Day, P.R. 1973. Genetic variability of crops. Ann. Rev. Pkutcpathal.
11:293-312.
Duggan, R.E. and M.fl. Duggan. 1973. Pesticide residues in food.
pp. 334-64 in Environmental Pollution by Pesticides. C.A. Edwards,
ad. Plenum, London.
Edwards, C.A. (ed.) 1973. Environmental Pollution by Pesticides.
Plenum, London.
EPA. 1974. Strategy of the Environmental Protection Agency for con-
trolling the adverse effects of pesticides. Office of Pesticide
Programs, Office of Hazardous Materials, Washington, B.C..
15
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EPA. 1976. Human monitoring program. Pest. Monitor. Quart.
Rep. 06. ;
Farkas, S.R., H.H. Shorey and L.K. Gaston. 1975. Sex pheromones
of Lapidoptera. The influence of-prolonged exposure to pherbmone
on the behavior of males of Trichopluaia ni. Environ. Entamol.
4:737-741.
FDA. 1975. Compliance program evaluation. Total diet studies:
FT 1973. Food and Drug Administration. Bureau of Foods, Washington,
D.C. H
Frankel, O.H. 1971. Genetic dangers in the green revolution. World
Agr. 19:9-13.
HEW. 1969. Report of the Secretary's•Commission on Pesticides and their
Relationship to Environmental Health. U.S. Dept. HEW, U.S.
Govt. Print. Off., Washington, D.C.
Hindin, E., D.S. May, and 6.H. DunstatU 1966. Distribution of in-
secticides sprayed by airplane on an irrigated corn plot. pp.
132-45 in Organic Pesticides in the Environment. Amer. Cham. Sec.
Publ.
Lupton, F.G.H. 1977. The plant breeders' contribution to the origin
and solution of pest and disease problems, pp. 71-81 in Origins
of Pest, Parasite, Disease and Weed Problems. J.M. Cherrett and
G.R. Sagar, eds. Blackwell Scientific Publications, Oxford.
McGarr, R.L. 1942. Relation of fertilizers to the development of the
cotton aphid. J. Scon. Entamol. 33:482-483.
Metcalf, C.I., W.P. Flint and R.L. Metcalf. 1962. Destructive'and
useful insects. McGraw-Hill, Nev York. 1087 pp.
Moore, W.F. 1970. Origin and spread of southern leaf blight in
1970. Plant Die. Septr. 54:1104-1108.
Kelson, R.R., J.E. Ayers, H. Cole and D.H. Petersen. 1970. Studies
and observations on the past occurrence and geographical distribu-
tion of isolates of Race T of Seltninthoaporiian maydia. Plant
Die. Septr. 54:1123-1126.
Oka, I.S. and 0. Pimentel. 1974. Corn susceptibility to corn leaf
aphids and common corn smut after herbicide treatment. Snviron.
Entomol. 3(6}:9ll-9lS.
Oka, I.N. and D. Pimentel. 1976. Herbicide (2,4-0) increases insect
and pathogen pests on corn. Science 193:239-240.
Pathak, M.D. 1970. Genetics of plants in pest management. Conf.
Principles Pest Management, March '25-27, Raleigh, North Carolina.
Pimentel, D. 1976. World food crisis: energy and pests. Bull.
Ent. Soc. Am. 22:20-25.
Pimentel, D. and N. Goodman. 1974. Environmental impact of pesticides.
pp. 25-52 in Survival in Toxic Environments. M.A.Q. Khan and
J.P. Bederka, Jr., eds. Academic Press, Nev York.
Pimentel, D., C. Shoemaker, E.L. LaDue, R.B. Rovinsky and N.P. Russell.
,1978a. Alternatives for reducing-;insecticides on cotton and
corn: economic and environmental impact. Report on Grant No.
;R802518-02, Office of Research and Development, Environmental
Protection Agency.
Pimentel, D., J. Krummel, D. Gallahan, J. Hough, A. Merrill, I. Schreiner,
P. Vittum, F. Koziol, E. Back, D. Yen and S. Fiance. 1978b.
Benefits and costs of pesticide use in U.S. food production. Manuscript.
16
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Pimentel, D., D. Andow, R. Dyson-Hudson, D. Gallahan, M. Irish, S.
Jacobsen, A. Kroop, S. Moss, I. Schreiner, M, Shapard, I. Thompson,
and W. Vinzant. 1978c. Environmental and social coses of pesticides.
Manuscript.
PS AC. 1965. Restoring the quality of our environment. Report of
Environmental Pollution Panel, President's Science Advisory Committee,
The White House.
Roane, C.W. 1973. Trends in breeding for disease resistance in crops.
Aim. Rev. Pkytopath. 11:463-486,
Roelofs, W., 1975. Manipulating sex pheromones for insect suppression,
Environ, Letters 8:41-59.
Roelofs, W.L., E.H. Glass, J. Tette and A. Comeau. 1970. Sex
ph«romone trapping for red-banded leaf roller control': theoretical
and actual. J* Soon. Entomol, 63:1162-67.
Savage, E.P., T. Keefe, and G. Johnson. 1976. The pesticide poisoning
rate is low. Agrichem* Age May:15-17.
Smith, H.E. 1971. Broadening the base of genetic variability In plants.
J. Saved. 62:265-276.
Stern, V.M. 1969. Interplanting alfalfa in cotton to control lygus bugs
and other insect pests. Proe. Tall Timbers Conf. Seal* Anim* Contr.
3abit. Mgmt. 1:55-60.
Stevens, N.E. and W.O. Scott. 1950. How long will present spring oat
varieties last in the central corn belt? Agron. J. 42:207-309.
Sweetman, H.L. 1958. The Principles of Biological Control. William
C. Brown Co., Dubuque, Iowa.
Thurston, H.D. 1973. Threatening plant disease. Ann. Rev. Fhytovathol.
11:27-52.
USDA. 1965. Losses in Agriculture. U.S. Department of Agriculture.
Agr. Handbook No. 291, Agr. Res. Serv., U.S. Government Printing
Office.
USDA. 1968. Extent of farm pesticide use on crops in 1966. Agr.
Econ. Rep. No. 147, Econ. Res. Serv.
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Econ. Rep. No. 179, Econ. Res. Serv.
USDA. 1972. Extent and cost of weed control with herbicides and an
evaluation of important weeds, 1968. Econ. Res. Serv.
USDA. 1975. Farmers; use of pesticides in 1971...extant of crop use.
Econ. Res. Serv., Agr. Econ. Rep. No. 268.
USBC. 1973. Census of Agriculture, 1969. Vol. 5. Special Reports.
Parts 1, 4-6. U.S. Govt. Print. Off., Washington, D.C.
van den Bosch, R. and P.S. Messenger. 1973. Biological control. Intext
Educational Publishers, New York.
van der Plank, J.E. 1968. Disease Resistance in Plants. Academic
Pr«ss, New York.
Walker, J.C., R.H. Larson and A.L. Taylor. 1953. Diseases of cabbage
and related plants. USDA, Agr. Handbook No. 144.
Watson, I.A. and N.H. Luig. 1963. The classification of pyccinia
grarri.n-i.3 var. Zriri
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Whitman, R.J. 1975. Natural control of the European corn borer
Oatrinia nubilalis (Hubner), in New Tort. Ph.D. Thesis, Cornell
University, Ithaca, New York.
Wolfe, M.S. 1968. Physiological race changes in barley mildew 1964-67.
Plant Pathol. 17:82-87.
18
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Part Two
Pest Management in the Interior West
19
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:o
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INTRODUCTION
I would love to call the local seed dealer or the extension
3erm.ce and say "bring me out about 10 eases of such and such
insect, I have corn rootuorm." I don't like going out there
and musing up Parathion to kill these insects. It's dangerous
to me, the environment; it's dangerous to everything.
I believe we need to have more development on cultural and bio-
logical controls in the region. He just don't have enough of
this type of information to take to the grower and say "this
is a cultural or biological program you can establish in your
field." As I see it, until we get some better information,
we are going to have to rely on pesticides in the immediate
future. We're not blessed with many alternatives at the present
time. '
These two quotes from the Pest Control Strategies Conference by a
Colorado farmer and Extension professor exemplify the state of pest
management in the region. Unlike California which has been very active
in developing alternative pest control strategies since the early 1900*3,
integrated pest mangement is still in its infancy in the Interior West.
Many representatives from regional agencies, organizations, farmers and
ranchers at this two-day conference expressed the need to make the transi-
tion to more environmentally and economically sound pest management
programs in the region.
As the papers in this proceedings indicate, integrated pest management
is not a panacea that will immediately cure the nation's pest problems.
Rather, it is a methodology that needs to be applied to specific crops,
their pests and the particular environment in which che crop is grown.
Ic was the aim of the planners of this conference to bring the national
expertise in alternative controls into the region to introduce new ap-
proaches for dealing with pest problems. Part Three explains some
alternative control strategies that have been shown to be viable in
various parts of the country and Part Four discusses the implementation
of IPM programs.
Using excerpts from panel discussions, presentations and papers, Part
Two focuses on some of the pest problems and current control strategies
in che Interior West. We have tried to provide a cross-section of views
on pest management from diverse perspectives. This synopsis of pest
management in the Interior West is important in assessing the task of
implementing more comprehensive IPM programs in the region. Several pro-
^r.ims will be discussed that are at various stages of development; for
xamula, a biological control program in orchards on the west slope of
C; Ion ado has been ongoing since 19&6. We hope this approach will be of
benefit not only co the region but to those who wish to see IPM implemen-
ted in other regions of the country.
21
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REGIONAL PEST PRflRlEMS
Colorado ranks first in the country in sheep and lambs on feed, third
in sugar beet production, fifth in cattle on feed and pear production,
seventh in sorghum and corn for silage, thirteenth in winter wheat,
and fifteenth in alfalfa hay production. Winter wheat and corn are the
two largest crops in terns of dollar value and total production (1977
Colorado Agricultural Statistics, Colorado Department of Agriculture).
Crop Pests
Excerpts from transcription of conference working session: William
Santabarger, session leader.
Approximately 80Z of the corn in Colorado is grown continuously on the
same ground. Where corn is grown continuously, corn rootwora is usually
a problem. In Colorado, corn accounts for the majority of insecticide
applications at the present time. We recommend a planting tine or
post emergence soil insecticide as an insurance treatement against corn
rootwora because we have no accurate way of telling if a particular
field needs control for the coning year. We have begun to look at an
adult control program as an alternative to treating with soil insecti-
cides each year. This will involve close field monitoring for adults
and selective spraying.
QUESTION: Doesn't spraying for adiilta lead to secondary pest resurgences?
ANSWER: lea, Bonks gross mite is our second most important pest in
corn and we hum we are affecting the mite 's parasites and predators and
thus creating our own mite problems with an adult spray program. This
is also true when controlling western bean cutworm which is rapidly
spreading in our region.
QUESTION: Save you tried Bacillus thuringiensis on the cutworm?
ANSWER: Zes. We have conducted field trials along with other pesticides
out it doesn't look too promising yet.
CCt&EIlT: There are difficulties with field trials for Bacillus according
zo -3X03 A3M studies. To get. a fair teat of MPV or 3asi I lus you have
~o use large blocks in areas of low chemical use. .4 eonbinaricn of bene-
ficial insects and microbials gives an additive effect ~ha- you do nor
n small ptjfs because of pesticide drift which biases agsirsr. -he
Ihe major pest problem on sorghum is the sorghum greenbug. This is an
-------
aphid that has a very toxic fceding secretion. We base our economic thres-
hold on plane size. Resistant hybrids of sorghum are being researched.
There is one pest problem on small grains which is rather detrimental as
far as the environment is concerned, the pale western cutworm. Popu-
lations increase in dryland wheat following a series of dry years on the
high plains. The only insecticide presently registered is Endrin which
is quite toxic to non-target organisms, particularly birds. We desperately
need some alternatives for this pest.
As an extension entomologist in Colorado, I feel we need better information
on economic thresholds. More information is needed on the basic biologies
and life cycles of major pest species. We also need more development and
more support for cultural and biological control investigations.
Noxious Weeds
Excerpts from transcription of conference working session: Eugene Seikes,
session leader, '
The two most important weed problems in Colorado are Canadian thistle
and field bindweed. Of less importance in our rangeland and cropland
are: bull thistle, Scott's thistle, musk thistle, Russian knapweed, and
the poverty weeds.
We do not have adequate controls for our perennial weeds. We can control
most weeds in Colorado but the economics are prohibitive in many cases.
We do not have good economical controls.
We have made several surveys in Colorado and we feel that weeds cost our
farmers about $2000 per farm. Weed control of Canadian thistle and
field bindweed costs farmers in the neighborhood of $100 an acre.
Many of our perennial weed infestations have started from contaminated
seed or feed. It was just a few years ago that the Colorado Department
of Agriculture placed embargoes on contaminated seed entering the state.
One of the control methods for Canadian thistle which we strongly re-
commend is a cultivation program involving frequent tilling. We also
recommend the use of good competitive crops. Some of the herbicides
recommend are 2,4-D, and, 2,4-D and Banvel combinations. Basically,
the herbicides simply starve out the root system by destroying the top
growth. This may take several years. When you consider that, the seeds
of some weeds are viable for approximately 30 years in the soil, it is
clear that weed control is a long-term project.
The tremendous root system of Canadian thistle is one reason that I feel
makes biological and cultural control difficult. There is enough storage
in the roots of Canadian thistle to last three years without much top
growth. If control insects die off or migrate within three years then
the weed will just grow back.
23
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There is probably more field bindweed than Canadian thistle' in crop-
lands. Field bindweed causes the biggest problem in dryland wheat
growing areas. Yields have been reduced in some cases by as much as
50*.
Weed control should be considered in any fanning plan. £ see chemical
weed control as a supplement to good farming practises.
QUESTION: Do you have the enabling type of legislation, in Colorado to
develop weed control districts? '•
ANSWER: Xetf we have tried to get a state-vide law out with no success.
t/e do have an enabling type legislation where counties as a, whole and
districts within a county can form weed districts* We do have a. few
of these districts within the state. They would be better replaced by
a state-wide system.
QUESTION: Do you have any recommendations on a system that would operate
on a no of low-tillage program in wheat farming?
ASSWER: Minimum tilling is good but it encourages weeds because the
soil is not turned over which permits the weeds to survive. In programs
of low-tillage, weed problems have been severe.
QUESTION: Save studies been run in relation to chemical weed tillage
also?
ANSWER: Not as much as could be. Most annual weeds associated with
mmmum tilling can be destroyed by use of 2,4-D. Vf will probably
have to use more herbicides with minimum tillage than we have in the past.
Range Insect Pests
Excerpts from transcription of conference working session: Lowell
.'•IcSuen, session leader.
For many years Aldrin and Dieldrin were the main pesticides used for
grasshopper control in range. They were, of course, very coxic to
wildlife, particularly birds. Malathion which is presently used, is
quite effective for grasshopper control and has little effect on wild-
life. Malachion is the only chemical chat che US DA recommends for large
spray operations.
Grasshopper spray operations probably involve several million acres of
rangeland a year. The typical spray program involves an entire block
of land ranging from 100 to 500 thousand acres.
J
During che last cen years, che USDA Range Insect Control research team
in Boseman, Montana has been developing a biological control program
for grasshopper control. The control agent is an endemic protozoan,
"ecsema locustae. Neosema feed on che grasshopper fac bodies and ic
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cakes about two weeks from Che time che grasshopper has been infected
co kill Che grasshopper.
The spores which are extracted from laboratory bred populations are
broadcast as an aerial spray. Each grasshopper contains enough sports
co treat two acres. The cose is about 25% to 30* of che cost for chemical
application.
One objection to the program is that there is not a quick knock-down
of che grasshopper population. This biological control program will
have co be fie into a total pest management system in which potential
infestations can be treated with Neosema before the infestations become
too severe. The USDA research team is also looking into the possibility
of a combination of a low dosage Malathion treatment for immediate knock-
down with the Hecsema spore release.
Urban Pests
Excerpts from transcription of conference working seas-ion: Byron
Reid, session leader.
The word sanitation seems to come up in almost every pest control area.
In urban areas it is of vital importance. In che ornamental area and
the fruit growing areas, sanitation has also been stressed.
A major point that was stressed during our session on urban pest control
was che overuse or misuse of pesticides by homeowners who buy che chemicals
off che shelf and use them without having proper knowledge of their use.
I see consumer education as an important facet of developing sound pest
mangement programs in urban areas.
In che urban and ornamental areas we scressed Che need co use pesticides
on an as-needed basis. Everyone in che room felt that we were looking
forward to che time when better alternatives are available.
Forest Pests
Excerpts from transcription of conference working session: Robert
Stevens, session leader.
The mountain pine bark beetle is the major forest pest in the Rockies.
The mountain bark beetles 'lay their eggs just below che bark layer of
Ponderosa pines where the larvae form galleries Co feed. The pine bark
beetle aces as a carrier for a blue-stain fungus which destroys the
transporting tissues of the tree and causes che tree's eventual deach.
Forescry is not a big industry in this part of the country so there
isn't aloe of industry incerest in the forest pest problems. The more
important values of forests in this region are recreation, aesthetics,
watershed and wildlife management.
We have to realize the lack of water on the Fronc Range. Though the
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area had a history of heavy lumbering around the turn of the century
the rate of turnover for the forest is too slow for viable lumbering
operations.
Forestry has some similarities with agriculture. We have monocultures;
contiguous stands of the same species. Many areas* however, have mixed
stands-with diverse age-structure and, as you might expect, fewer pest
problems. In forestry-, of course, we don't plant the crop in April and
harvest the crop in September. In fact, in most cases we haven't planted
it at all and have no plans for harvesting.
One difficult aspect of forestry pest management is the time it takes
to grow a crop and how that affects certain techniques like breeding
resistant hosts. In the case of the mountain pine bark beetle, it takes
approximately 50 years before the pines are even susceptible to attack.
You can screen a tree for a particular turpine content which seeas to
be resistant to the pine bark beetle and not know for 50 years if you
made the proper selection. Also, because the insect populations turn
over at least once a year, the chances are clearly in favor of the insect
changing faster than the host tree species.
COMMENT: Ian 't the longevity and stability of the forest ecosystem a
factor that is also in your favor. For example, the use of natural
3nem.es has been shown to be more successful in stable systems sush as
orchards than in croplands where radical changes occur each season.
The result of that early logging along the Front Range has been the
development of a monoculture of Ponderosa pine, even-aged and very dense.
This is the optimal situation for infestations of mountain pine bark beetle.
In dealing with forest pests we like the approach of fiddling with the
hosts, a process known as environmental and habitat management, rather
than trying to control the pest population.
Our program for fighting the pine bark beetle is a rather unsophisticated
IPM program. It involves the use of pesticides for direct control coupled
with the cultural approach of thinning stands. Ideally, this type of
cultural approach would be best done in advance of the problem. Unfortu-
nately, we have, by necessity, to attempt control right in the midst
of the. problem.
QUESTION: Is there anything being done about the possible use of para"
sizes for a control program?
ANS1SE?.; Ike parasites are of little importance; the predators of
slightly more importance. Clerid beetles and woodpeckers are s factor
but they are not dependable.
CCMKEiJT: Some studies have indicated -hat there are fairly sizable pop-
ulations of parasites in moist environments in Colorado, along ravines
•snd canyons. :2n the exposed knells or in zeric environments, the popu-
lations were vuch lower. So it appears that the parasites can be effec-
tive but -in very selective situations.
!
26
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COMMENT: One of the problems in the use of parasites for control programs
is that the parasites have to eat. I feel that some realeases have failed
because a basic food source for the adult was not available. There are
lots of ichneumons that can find a batch of eggs or larvae beneath the bark
but they must have moist, food sufficient, areas in which to live. 1 think
that the bark beetles are probably much more uniformly distributed than
damage let's us know. I/here there is food and water for the adults, you
have a healthy population of parasites keeping the infestation dawn at the
sub-economic level.
QUESTION: Isn't it true that female pine bark beetles are attracted to
pheromone traps and if so can't you use that as a control method?
ANSWE3: Tnere has been alot of pheromone work done on bark beetles and
the results are rather spotty in general. Me haven't been as successful
with bark beetle pheromones as with the lepidopteran pheromones which are
largely sex pheromones; bark beetle pheromones are aggregating pheromones
which is quite different. Pheromones are used to sample population densities
of pine bark beetles.
It will be interesting to se« what happens in Rocky Mountain National Park
where there is no control for pine bark beetle. I think they are doing
the right thing up there and the State Forest Service is doing the right
thing by trying to control the beetle near the cities.
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VIEWS CN PEST MANAGEMENT
Gl«n Murray if a farmer front Brighton, Colorado. He produces grain,
corn and alfalfa on an irrigated farm which is used to support the cattle
industry in the general vicinity. 3e is a member of the Rooky Mountain
Farmer's Union.
First, lac m« begin by giving a little personal background. I have been
in this buisness of agriculture directly or indirectly all my life. I
was born and raised on an irrigated farm and have received two degrees
frdm Fort Collins in agronomy.
You have all heard about the problems that agriculture is in today. I
would like to give a little history of what is actually going on. Today
in the United States approximately 4Z of the population is involved in
agricultural production. That percentage is smaller than anywhere else
in the world. The income of the average farmer for this past year was
approximately $3,000. By way of comparison, the average factory worker
earns approximately $12,000. Now that doesn't sound too drastic in itself,
except when you consider that income involves the farmer's entire family.
You can see that agriculture today is having some real problems. Another
fact is that in farming today, the average farm is valued at a quarter
of a million dollars. The average return on chat investment is four per-
cent. You can see that unless, as the old saying goes, you marry it or
inherit it, you do not get into agriculture today, at least not in the
production end.
One point that was brought up today deals with the economics of size. In
other words, the big corporation has it made. The point that has not
been brought up is that when you look at Che efficiency of corporate
agriculture, studies indicate it has been much less efficient Chan the
family farm or small farm operations. I question the concept chat bigness
is better; the statistics don't prove it out.
People*, today, are always calking about our standard of living, about how
high priced everything is. Ona should stop and look around che world and
make some comparisons. We enjoy a higher scandard of living in this
country Chan anywhere in the world. Why do we enjoy this high standard
of living? The major reason is che cost of food. We pay less chan 17%
of our disposable income for food in chis country. That is lower Chan
anywhere in che world.
The issue of monoculture versus diversified farming came up chis morning.
Someone asked "why doesn'c everybody grow a little of everything."
There are several reasons for this. The main reason boils down to eco-
nomics again. The producer cannot afford co do Chat for two reasons.
28
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One is the cose of machinery. Today, a small combine is going to cost
you about $60,000. How many ten or fifteen acre plots do you have to
have to pay for that $60,000 machine ? You can say, "Let's use labor
and then you don't have to use that machine," but then where do you get
the labor and how do you pay the $5 or $6 per hour that it takes to
compete with the urban market ? You just can't do it.
This conference, however, is concerned with pest management and I would
like to explain my viewpoints. Mr. Tweedy defined integrated pest
management very well and I agree with him. I hate to use chemicals
just as much as anyone else but unfortunately, at the stage of the
game today, it is one of those necessary evils. I am on an irrigated
farm where highly intensive agriculture is conducted and for me that is
the way I see it.
The people that profess not using any chemicals in agriculture don't look
far enough down the road. I would love to call the local seed dealer
or the extension service and say "bring me out about ten cases of such
and such insect, I have corn rootworm." I don't like going out there and
mixing up Earathion to kill these insects. It is dangerous to me, the
environment; it is dangerous to everything. The worst part of it is that
it does not always work. I think, presently, it is basically a re-
search question and this is where I am going to lean on the research
people. There needs to be alot of work done. I think there is some real
potential in cultural control programs, biological control programs and
in resistant varieties.
The one thing I would like to leave with you is that today in the United
States, the American farmer feeds this country and a good portion of the
world. Now, if we want to take a step backwards and eliminate chemicals
from agriculture, that's fine. But I want you to think about the impli-
cations of this. Food is really the only thing chat this country can
export to balance our trade deficit. If we eliminate chemicals completely,
we are going to have problems.
Thomas Lasater is a rancher from Matheson, Colorado, 'de has developed
•ynd expanded 7he basic 'nerd of one of the tuo modem breeds of cattle,
the Beefmaster.
Many years ago an old Texas cattle friend was travelling through some
of che back country in Mexico and saw this roadside establishment and he
thought he would stop in for a cup of coffee. He stepped inside, ordered
a cup of coffee and looked off to his right where an elderly Mexican
gentleman was having lunch. His plate was completely covered with flies.
This old fella was paying no attention Co the flies, just happily eating
away. Finally the Texas turned to this old Mexican gentleman and said,
"pardon ae, but don't chose flies bother you?" The gentleman replied,
"oh no, chey eat so little."
29
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Before launching into the main subject today, I would like to say a word
about land ownership. We do not and I am sure many of you do not look
upon the ownership of land in the same category of awning a home or own-
ing an automobile. We are merely temporary custodians of the land. It
is up to each one of us to pass on to the next succeeding generation a
better piece of land in better condition than we received when we took
over.
The same philosophy should also apply to the environment. It is, of
course, of paramount importance that each of us should familiarize our-
selves with our own «nvironment. Secondly, we should take definite steps
in our daily lives to do something about it, not just talk about it.
At our 'ranch in Matheaon, Colorado, w« have never used herbicides and
in 1949 discontinued the use of all pesticides. We used to spray in
December and February for lice. An interesting point to us is that we
havtt fewer lice problems on our cattle in the wintertime today than we
did when we sprayed. As w« all know, each animal, including insects,
has its own natural enemies and apparently we ware killing more of the
louse's natural enemies than we were lice. Once we quit spraying the
natural enemies took over and have cut down the lice population sub-
stantially.
Another interesting thing is the matter of predators. When predators and
their victims are left to their own devices, they will seek a balance.
For instance, when we first came to Colorado, we literally had thousands
of thousands of rabbits on the ranch. We had three different species
of rabbits. We mov«d in with a no-huntiag, no-trapping, no-poisoning
policy. Nature immediately brought in hordes of coyotes and they cut
the rabbit population down to a normal size. As soon as they finished
the job the coyotes left, leaving a stand-by crew to maintain the situa-
tion.'
We were unfamiliar with prairie dogs when we arrived and the neighbors
and the county agent told us we should kill the prairie dogs. We had
ona prairie dog town and, unfortunately, we took their advice and
poisoned them. Several years later, I was riding across the pasture
with a friend and he pointed to where this prairie dog town had been an
asked, "why is the best grass in this pasture right over there?"
I replied, "chat's where the prairie dogs were." Since then we have
imported two different batches of prairie dogs and they have refused
co settle on the Laaater ranch. They all go off to the neighbors and
I am sure they get poisoned.
A wealthy Texas oilman bought an island off the Texas coast so he and
his friends could go quail hunting, a regular quail preserve. There
were*alot of hawks out there so he sent these hunters co obliterate the
hawks. The quails vanished. They found' out that the ha.*ks were eating
the mice and thus keeping the mice from eating the quail eggs. When
chere were'no hawks, the mice multiplied, ate all the quail eggs and that
ended the quail hunting. These examples show chat it is best co leave
nature alone.
30
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He often talk about the balance of nature. Actually, nature operates
in Imbalances in the short-time frame. Some examples are tornadoes,
cyclones, floods, and droughts. In the long-time frame it all balances
out. A perfect example of this was the migratory practices of the buffalo
in the early days. They moved from the panhandle of Texas up into
eastern Colorado in these huge herds of four or five thousand and they
would absolutely decimate the country as they migrated. They ate grass,
shrubs, trees, everything; what they did not eat they would trample down.
The following year the migratory route of the buffalo would be further
to the east or west and they wouldn't come back to the same spot for at
least two or three years, giving nature a chance to restore the land.
Pauline Plaza-.'is on the staff of the Western Environmental Science Program
of the National Audubon Society. Ms. Plaza received her M.S. in Vildlife
Biology from Cornell University.
The National Audubon Society is involved with a large variety of issues
across the country. At our office here in Lakewood, Colorado, we cover
mostly the western issues: everything from oil shale to golden eagles
and things in between. Some of the comments I am about to make may seem
strange to you if you are thinking only in terms of crop pests, but if
you think in terms of prairie dogs versus cattle, or golden eagle depre-
dations on lambs, they make more sense.
I would like first to describe a couple of the major environmental
goals of the Society. Most people know roughly what they are but seldom
see them in print. The two of interest to us here are: the conservation
of wildlife and the natural environment; and the prevention and abatement
of environmental pollution in all its forms. These are very general goals
that the Board of Directors formulated some years ago. Included under
the second of these goals is "advocating biological and integrated pest
control measures." This is our attitude towards Integrated Pest Manage-
ment. However, the Audubon directive adds, "while working to eliminate
persistent and highly mobile pesticides and toxic substances that poison
the food chains of natural ecosystems." So, on the one hand we are very
interested in biological control. On the other hand, we discourage the
heavy and exclusive use of chemical pesticides as practiced in American
agriculture in the past. I think agriculture is in a period of transition
right now.
The Audubon Society has a long record of opposition to the exclusive use
of chemical pesticides. The reason for our position is not hard to
understand. We are concerned with environmental and social costs that
are not usually included in a cost/benefit analysis of pesticide use.
These are hidden costs that go back twenty or thirty years. They were
certainly not foreseen then, but we do know about them now.
Environmental costs include the massive disruption of complex biological
communities and the loss of function of some of these communities. For
example, early applications of DDT essentially eliminated bird and insect
31
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predators in certain areas and threw the whole local food web out of
kilter. The end result, as we all know, was an increase in the number
of pest individuals because their natural predators had been destroyed.
What the other ramifications of removing species from their communities
ara, we are just beginning to find out.
Consider also that intact natural communities perform valuable services
for man — e.g. flood and erosion control, air and water filtration,
and moderation of temperature extremes, among others. You can see that
these communities are quite important to human welfare, whether we
realize it or not. Uhen we disable them we must replace their functions
with man-made systems at enormous cost. Apart from their functional
importance, natural communities have aesthetic and recreational values
which we are just starting to recognize and, in some cases, quantify.
Other environmental costs that the Society is concerned with are the
direct losses of fish and wildlife and, particularly, the indirect losses
through the concentration of persistent, toxic chemicals along the food
chain. The decline of the peregrine falcon is a good example. Most of
you have heard this story before, but I think it's worth repeating. The
peregrine was a fairly widespread breeding bird up to 40 years ago. It
has been eliminated as a breeding species in the eastern United States
and severely decimated in the West due primarily to the use of DDT. It
survives in the eaat only because of captive breeding and reiutreduction
efforts. In Colorado only six out of 30 historical eyries are still
active, an 30% reduction. The problem is not destruction of habitat -
the habitat is mostly intact - but rather eggshell thinning and consequent
low reproductive success. DOT has been incriminated as the chief
agent of this process.
So - how do you put a cost on a thousand peregrine falcons aad the dis-
ruption of the natural community in which th« peregrine is on the top
of the food chain? These kinds of costs are hard to quantify, though
you could, for instance, find out how much is being spent each year to
breed and restore peregrines to the wild. Gae estimate is $2000 per
young bird.
The 'Audubon Society is also concerned with the social costs of pesticide
use. There arw first the direct costs of human life due to sistfekas in
application of pesticides. There is also the deterioration in human
health and efficiency due to sublethal doses of pesticides. Then there
is the direct cost to the farmer of increased pesticide use. As the
natural enemiss of pests are eliminated by extensive spraying programs
and f-the few naturally immune pest individuals b*gis to breed, 3*coadary
pest outbreaks occur, worst than the first. As this spiral accelerates,
yields start to drop, a* documented cases* prove. The end result is an
increase in direct costs to the farm*r, with the possibility that h« will
be driven oat of business by the combination of increased costs of pesti-
cides and reduced crop yields.
32
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There is something else we have not quantified yet. That is the long-
term cost to society, in health care for example. Or the eventual costs
of an agricultural system that relies on chemical pesticides and destroys
the natural communities that could provide a buffer zone for predator
species. We Just do not know what those costs are.
/ '
I think you can see chat the Society is very supportive of integrated
pest management. Some aspects appeal to us more than others - biological.
controls, cultural diversification, less use of marginal land for farm-
ing and livestock grazing and more emphasis on lands that are well adapted
for these purposes.
When a pest problem arises, we keep several considerations in mind:
1. Is there really a problem? This may seem a strange question if you
are standing out in the middle of your field and insects are crawling
around you, but in other cases this is a valid question. For example,
are vertebrate predators on livestock really a problem? Were the
huge blackbird roosts in Tennessee and Kentucky a real hazard to human
health? The problem is usually the icing on the cake; all you see is Che
icing and you may not see the basic problems underneath.
2. We always consider the safety to humans of the control method, whether
it is a pesticide or not.
3. Is the control method specific? Is it aimed just at the pest?
We do not support the use of broad spectrum control methods because
they play too much havoc with natural communities.
4. Is the method affective and efficient? Like everyone else, we don't
like to see taxpayers' money spent on methods that don't work or
which can only lead to escalating costs. We protest some measures
on that basis.
5. Most importantly to us, and I think to a lot of environmental organ-
izations, is the question of what the long-term impacts of pest
control methods will be. Again this stems from our concern for the
maintenance of natural communities or che biosphere, if you prefer
to call it that. I cited the loss of che eastern peregrine falcon
population as an example. This is a long-term impact chat we did
noc foresee but which we now know to have been directly related co
che use of DDT and other chlorinated hydrocarbons. We don't know
about ocher methods, but at least we know there can be this kind of
effect.
6. Then lastly, a question we are concerned with is: what are che
synergistic effects of the control action? Sometimes a single action
can have multiple affects. Draining a swamp co control mosquitoes
has impacts on flood control, ground water levels, water quality,
wildlife abundance and a number of other factors. When a wetland
is drained, you are not just getting rid of mosquitoes but rather
affecting many other parts of the anvironmsnt. The question arises
whether che benefit, in chis case che projected absence of mosqui-
toes, is worth che costs which you may noc be able co quantify or
even predicc. These mulciple effects must be kept in mind.
33
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Another of the Society's major concerns^is the exportation of American
agricultural techniques to foreign countries. Audubon does quite a bit
of work in Mexico. We have done biological surveys in Central and
South America in which we were concerned mainly with migratory birds
such as waterfowl, shorebirds. songbirds and some raptors. The United
States is still exporting hard pesticides to these countries. Their use
is having disastrous effects not only on the wildlife and natural eco-
systems of these countries but also on the economic structure and social
stability. We really question whether we should export our technology
abroad. You may say it increases food yields. This may be true temporar-
ily, but in the long run the effectiveness of chemical control has been
shown to decrease. Are we morally justified in exporting a process which
we now know will not work in the long run?
One thing we would like to see is exportation of Integrated Pest Manage-
ment techniques. If we are going to export technology, let's at least
export an effective and efficient one.
The Society's actions include legislative lobbying by our office in
Washington. We also have direct contacts with the executive branch and
the agencies having jurisdiction over pest control. We also have quite
a large public education campaign. Most of you have probably seen our
magazine.
To summarize, our basic concern is the long-term effects of certain
pest control methods on ecosystems, on wildlife and on humans. All life
ultimately depends on the functioning of complex biological communities.
Audubon's concern is the maintenance of the whole complex of interdependent
species and the abiotic environment, not just crop ecology. W<* realize
chat choices sometimes have to be made between human health and a temporary
disruption of natural communities, but such cases are relatively rare.
We urge that biologically sensible methods be used to control pests;
less damaging techniques than the blanket application of broad-spectrum,
toxic persistent chemicals. I think that American agriculture will
eventually move away from this. The sooner the better as far as we are
concerned.
Wayne Bain ia the executive secretary for the Mesa. County Peash Administra-
tion Committee which is a. grower organization for fruit growers en the
•jest slope of Colorado.
I would like Co make a few recommendations regarding pest management.
I made a telephone call yesterday and I noticed an interesting ching
chat I chink applies co the problem that we may have with growers accept-
ing IPM. When I was making the call, I noticed chey had a small black-
board beside the phone Co prevent people from writing on the wall. Some-
one was intelligent enough to provide a good alternative co writing on
che wall. This is Che first thing Chat I believe that growers need:
a low-cose efficient alcernative method of control Co pesticides.
34
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The second recommendation is Co sec up a. procedure for faster and better
chemical evaluations by those concerned. I had not realized, until Mr.
Reese explained yesterday, that court cases were one reason for the delay
in chemical registrations. Another recommendation would be a more logical
review of the risk/benefit ratio in considering the use of restricted
chemicals.
I read recently that it had been suggested to form a group called the
Inter-agency Regulatory Liaison Group with representatives from OSHA,
EPA, FDA, and the Consumer Product Safety Commission. What bothers me
about this, and Mr. Reese also commented on this, is that it is very
difficult to have multiple agencies working on a common problem. It is
also difficult to have one involved with regulation and another charged
with the responsibility of compliance. I think all this responsibility
should be centered in one single body. Mr. Reese stated that the regula-
tory aspects of pest management had been pulled together more or less
under EPA but he made the point that the aviation group still monitors :
one segment.
The last recommendation that I would like to make is to use some diplomacy
in tackling grower relationships. A good government/grower relationship
would result in a more willing compliance as opposed to the use of force.
Growers are getting highly sensitive about the number of regulations th\t
they have to operate under.
I'll close with a quote, I do not know the author. It states, "private
initiative often works hardest when government intervenes least but seldom
have we given it a real chance to work. It is a rare case when the
passing of a law cures the problem."
Allan Jones is a. fruit grower from western Colorado producing peaches, :
ipples and pears.
I represent some 200 peach producers in a marketing association in western
Colorado. This grower organization is highly organized and can do many
things that other groups cannot do because each producer within this group
has to pay his fair share. Voluntary methods have never done the job.
Pest management, in my opinion, is a huge ball of wax and there is no
accurate way co evaluate what is good and what is harmful to mankind. I
see pest control'as a war, a battle to grow enough food and fiber so that
people can live well. I have used chemicals for some thirty years. As
a fruit grower, I have ridden a spray rig for many years, and although
I have a lot of gray hair now, I am still around. Every one of my children
raised on our orchards is healthy. Lack of caution and carelessness can
be a problem in the application of chemicals but I doubt chat there is
very much proof chat a chemical properly used has killed anyone. I am
sure chat this is debatable and I will be taken co cask for what I say.
35
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As a producer, and I know a, good many producers across the country
who feel the same way, I am somewhat reluctant to believe our government
any more. I dislike saying this but that is how producers see it. We
get statistics till they are running out of our ears and often one set
of statistics disproves the other. Agencies fight among thenselves, one
agency not knowing what the other is doing. We don't know what they are
doing. I hope that as time goes on we will have less government in our
business.
To get to the point of today's discussion, we have been involved with
biological control for some 32 years in the industry. It is not anything
new to us. Around 1946, the peach industry found itself in trouble with
the oriental fruit moth. We started to develop a control program with the
Colorado Department of Agriculture. We furnished a large part of the money
in the beginning. Since that time we have had an integrated program on the
oriental fruit moth. We raise a lot of the parasite Mocrocentrus . The
cost of the control is $7 per acre versus $30 per acre for chemicals.
You know chat we are in business and that we are going to use the best
method to control this fruit moth. We use both the parasite and chemicals
to get the job done. In our area we are always looking for new control
methods. At Che present time, the Insectary in Falasidtts which is thy
only one in Colorado has five programs in biological control. We are
very ^appreciative of the Colorado Department of Agriculture and its insectary
on the west slope for the job they are doing.
We also have another group of people in the state that we are quice proud
of and chat is Colorado State University. They give us help by writing
a booklet each year that we call the "Fruit Grower's Bible." This booklet
outlines the different control programs that we might use, the sprays,
hew ouch to put on and when to spray. So we have two different organiza-
tions chat are working wieh us and each' doing a good job.
If you want to keep pests at a mif1'™^, first you need proper sanitation.
In our area we have pest districts. The growers monitor themselves and
there are also inspectors in each area. If a grower doesn'c spray at che
right' ciae or lets a pest get out of hand, he is told to cake care of it.
If he doesn't, somebody else will take car* of it for hio.
We have uaed biological controls, predator aitas and par as it as, for che
elimination of oriental fruit moth and we are still using chemicals.
Thera is a gancleaan in che audiiince. Les Ekland, an IPM consultant, who
works for me. I pay him a pretty good -salary out of ay pocket but I think
he is probably going to save me money. ' We use as little chemicals as
possible; chat is why Les has a job. W« used ea apply five or six sprays
a season for apples. Now, Les watches his pherotatrae craps and tells us
when .co spray. Unfortunately, you can get a bad case of ulcvrs sitting
around waiting. W* used to spray whenever che University said so., whether
wo needed co or cot. Les has taken all this gamble out of this.
To summarize, we are going co have co work cogecher ca gcc che job done.
We don't chink chat government intervention in our business is che answer
Co chis thing. Ic is up GO us. The program I have listened to chese lasc
two days has enlightened me greatly about what our chances are co do &
job and use less chemicals doing it.
36
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REGIONAL PROGRAMS IN INTEGRATED PEST MANAGEMENT
BIOLOGICAL CONTROL PROGRAMS
Albert Marlino
Colorado Department of Agriculture
Insectary Section
The , Colorado Department of Agriculture, long before the term "Pest
Management" came into usage, was committed to biological control with
the introduction of the Oriental fruit moth, Grapholitha. molasta (Busck)
in 1944. Since the biology of this pest did not respond to chemical
controls, a mass rearing program of the parasite Maarocentrus anaytivorus
was initiated in 1946.
The outgrowth of this initial venture into the biological control field
resulted in the Colorado Department of Agriculture, Division of Plant
Industry establishing the Insectary Section which is based in Palisade,
Colorado. Sine* that time, working with the United States Department
of Agriculture and related agencies across the nation, Colorado has be-
come involved in many beneficial programs which have had significant
impact against some important pests in the region.
This has proven to be true with the releases of Oriental fruit moth
parasites where there is full cooperation with the peach growers. The
parasites are timely released by using the data from trapping the moths
by the pheromone method, maintaining records of applied pesticides and
calculating the degradation time of toxic residue by the bio-assay method.
This program is unique to the peach growing district of Western Colorado
and has reduced chemical application requirements from 3 to 1 and in-
many cases none.
There are 3 to 4 generations of Oriental,fruit moth in Colorado. The last
generation occurs preharvest when larval damage would be expected to be
the greatest. Timely utilization of Macrocentrus ancylivorus has eliminated
Che need for chemical control as evidenced from harvest samples showing
0 co 2 percent damage, averaging .23 for orchards monitored in 1977. The
*ff•ctiv«n«aa of this parasite has been aptly demonstrated. Cooperation,
record keeping, analyzing crap data and communication between che peach
grower and the insectary is the primary consideration for a successful
program.
i
Monitoring of cwo-spotted mite, Tetranychua wrcioae, populations and the
utilization of the western mite predator, Typhlovamus oaciden-zlis (Guthion
resistant) in fruit orchards has been one of great interest. Results,
chus far. Indicate chat chis predator can effectively contol mice popu-
lations under properly managed conditions. However, che question remains,
t
37
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does the average grower have the knowledge and cools to effectively
evaluate th* problem?
In working with the Dutch elm disease problem, Ceratoayatia utnri and
its vector Scolytua multiatriatus, a parasitic wasp Dendroaoter protubercma
imported from France by the USDA and supplied to Colorado for rearing and
release, has been successfully established and monitored since 1974.
Eventually all counties in the state having populations of this beetle
will recieve parasites.
The parasite has effectively overwintered at primary release sites and
recovery studies have shown a maximum of 30% parasitism. Studies also
indicate that D. protuberons will also parasitize Scolytua ruguloaua,
shot hole borer of peach and other fruit trees, as well as the olive bark
beetle, Leperisinua oalifornioua taken from infested blue ash trees.
Colorado has, over the years, made successful introduction and colonization
of other exotic species. Probably one of the first was Cfuryaolino. quod-
rigenrLna introduced to suppress Klamath weed, Bypericum perforation, in
1956. Klamath weed is toxic to livestock. The weed, especially trouble-
some in the Rocky flats area of Boulder county, is now well under control
by this imported Australian beetle.
More currently, introductions of Rhinoaylua aoreLcua, a seed weevil from
Europe, have been made in an effort to suppress Corduua nutons, the musk
thistle. Surveys confirm the thistle to be readily established and com-
peting with desirable plant species in IS counties of the state. Trial
releases began in 1974 and establishments have been made in Larimer, Mesa,
and Eagle counties. Two sites in Larimer county which were at explosive
population levels now show marked reduction of thistle. Collections for
sub-colonization to other infested areas of the state were made in 1973
from one Larimer county site. The weevil is expected to be a successful
adjunct in suppressing the thistle and relieving costly labor and con-
trol costs.
In the forage crop area, the Indian wasp, Aphidiua smithi, was introduced
to assist in suppressing Illinois piai, the pea aphid, which was causing
tremendous damage to legume crops. The introduction was successful and
collections from established sites were made to other problem areas of
the state. Since its introduction, pea aphid complaints have been minimal.
Two new programs now in progress are the rearing of Liotryphcn sp. ob-
tained from the University of California, which parasitizes Laapryeaia
.pcmcnelLz, the codling moth, and investigations are underway co determine
che suitability of a biological control program utilizing parasites of
Hemiieuoa oliviaa, tha range caterpillar. 1977-78 overwintering trials
of Liotryphon ap. were successful. This large, docile parasite-predator
from Afghanistan may well fit into areas where organic farming is practiced
and.in areas where pest and ornamental host trees harbor populations of
codling moth larva.
Cooperative efforts with Colorado State University, Zoology-Entomology
38
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Department, featured studies of alfalfa weevil parasite, hyper-parasite
spectrum, relationship to weevil control and parasite protection with
respect to hay height, olfactory response studies to certain sex phero-
mones as to whether parasites react favorably to the pheromone of its
host and recovery studies of the elm bark beetle parasite, Dendccsoter
protuberana.
In summary, the Insectary Section of the Colorado Department of Agricul-
ture's Division of Plant Industry is committed by law to rear, release,
introduce and colonize exotic beneficial insects as they become available
through USDA agencies for integrated control of entomophagus and phyto-
phagus pest species. Reciprocity in exchanging biological agents is a
unique feature enjoyed with other states and countries. Furnishing para-
sites of Oriental fruit moth to Russia and Australia highlights the respect
Colorado enjoys in the biological control field.
39
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IBEEGRA1ED PEST MANAGEMENT HI ALFALFA
Donald W. Davis
Department of Biology
Utah State University
Logan, Utah
Alfalfa was one of Che first crops considered for an integrated pest
management program. Many of the earlier attempts at integrated control
and supervised control were centered on alfalfa and when the major crop
systems were selected for detailed pest management and agroecosystem studies
about 8 years ago, alfalfa was one of the, 6 selected. Alfalfa has features
that make it an ideal crop for integrated pest management as well as features
that are undesirable.
(
Favoring IPM, alfalfa has the following:
1. It has a liberal economic injury level. In other words, a
significant amount of pest activity can be tolerated.
2. Most plantings are fairly large.
3. In most areas there are relatively few key pests; in the
northern Great Basin there is only one on forage alfalfa.
4. It is a perennial crop with considerable latitude for mani-
pulation of cultural practices.
5. Alfalfa .fields contain a wide variety of insects and other
organisms, many of which are highly beneficial.
6. Insects found in alfalfa fields commonly interact wich adjacent
crops.
7. There are many cultivars available with various degrees and
types of pest 'resistance.
8. Pesticide residues must be minimal.
Features discouraging IFM:
1. Alfalfa has been commonly considered as a low value crop; while
this is slowly changing, the reputation persists.
2. In many parts of the country alfalfa is a rotation crop or an
ingredient in pasture mixes. When pests move in, growers switch
to clovers or other crops.
3. Forage alfalfa in many areas is not a high pesticide-use crop,
:. therefore the volume of pesticide use nationally will not be
changed greatly even if all alfalfa pesticides were discontinued.
Before any integrated pest management program can function, there must be
extensive data accumulated. In all programs there is constant inter-
action between the crop, the pests, the various pest-limiting factors,
and economics. Basic to all of these factors are such things as long-
-------
range climate, short-term weather and soil types. If these factors can
be measured, they can be used as predictive tools.
Our first need in the alfalfa pest management program is to recognize
the basic factors limiting yielas. These include many things in addi-
tion to pests, but in this discussion we will center on the pest pro-
blems. Each pest has many factors restricting its unlimited development.
They are often referred to as natural controlling factors and include
parasites, climate, plant resistances, etc. In working with forage
alfalfa in northern Utah we decided the key insect pest was the alfalfa
weevil, accounting for about $5 million loss in the state annually.
Common secondary insect problems were pea aphids, about 5 species of
caterpillars, lygus, and grasshoppers. The primary limiting factors
related to the alfalfa weevil are: parasites, especially Bathypleates
aurculienis; several predators; the harvesting dates of alfalfa crops;
the type of harvesting; climatic conditions, especially during winter;
and insecticide treatments. Each of these limiting factors is inter-
related with many other factors and, except for climate, most are subject
to a certain amount of manipulation. We are continually measuring these
factors and expanding their use for both predictive and strategy functions.
A second major need in our pest management program is to improve sample-
ing and monitoring methods. No single technique serves all necessary
functions. We make use of the sweep net, insects per terminal, the 0-Vac,
and visual damage ratings. The sampling method must be changed and
modified to meet the requirements of the crop. Methods are changed
according to the stage of alfalfa growth and expected pests in a given
season.
The third key ingredient to our pest management program is to evaluate
various control strategies. This evaluation must be related to factors
within the alfalfa fields and to those outside the fields. The impact
of one control strategy interrelates with other control strategies and
with economics. We must consider three general control methods related
to the alfalfa weevil that can be manipulated by growers: cultural practices,
chemical control and making more efficient use of beneficial insects.
Experimentally we work with other concepts such as the introduction of
new parasites, but they presently are not part of grower strategies.
The basic model used in our work is chat developed by the NSF-EPA supported
alfalfa ecosystem studies. This work was done through an interstate
cooperative effort in which Utah was a major cooperating state. The alfalfa
plant model and alfalfa weevil model work rather well for us in our pre-
dictions. Unfortunately, the project was discontinued before other insect
pests could be worked into the model. In Utah, we are now working with
the economists to include an economics model into the system.
Several states are now using pest management systems relating to alfalfa
pests. Most of these are on forage alfalfa, but a major effort is being
made also against pests of seed alfalfa. In Indiana they have establish-
ed a network of computer cantors with regional divisions. In each of
theaa regions a record of degroo days, progress toward harvesting daces
and unusual problems are kayod into cho computer. A grower or a pest
41
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management scout checks for alfalfa insects using a predetermined sampl-
ing method. His counts are phoned into the regional terminal and within
a few minutes the advisory message is returned.
In Utah, due to the vast number of different conditions in the mountain
country, we have been relying more on samples obtained at 50 degree
day intervals. The decisions are made based on data relating alfalfa
weevil numbers to growth stages of the alfalfa.
Under Utah conditions we can commonly suppress alfalfa weevil populations
sufficiently to avoid insecticides by using cultural practices. The most
effective cultural practice is cutting about a week early. During most
years, the first crop of alfalfa can be cut before the alfalfa weevil
larvae reach their peak feeding potential. Larvae that are still in the
third instar are killed and the crop is cut before substantial injury
appears. Sometimes it is necessary to use a stubble spray following har-
vest, but often cutting alone is adequate. Chemical use and cultural
practices are manipulated in such a way that predators and parasites are
preserved.
We can keep pests below economic injury levels without pesticides in more
than one half of the fields during most seasons in Utah by manipulating
cultural practices. This compares to about 602 of the fields normally
sprayed for alfalfa weevil control plus about 10% sprayed for other pests.
Of the approximately 35Z of the fields under pest management requiring
insecticide treatments, about half can use stubble sprays which do little
harm to beneficial insects and create almost no residue problems. This
leaves only about 157. of the fields requiring either early season or pre-
harvest insecticide treatments. The preharvest insecticide treatments
concern us the most. They can control the alfalfa weevil effectively,
but create several serious problems: 1) They are applied during the
height of beneficial insect activity. 2) Because treatments are made
only 2-3 weeks before harvest, it is easy to miscalculate dosages or
timings and get into residue problems. 3) When ground sprayers are used,
considerable physical damage is done to the crop. Through the establish-
ment of new parasites, manipulating other cultural practices, and more
precise prediction methods we hope to continue reducing the number of
preharvest treatments. In the meantime we recommend either selective or
shortlived insecticides whenever possible.
42
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THE NEED FOR INTEGRATED PEST MANAGEMENT RESEARCH IN RANGE
B. Austin Haws
Department of Biology
Utah State University
Logan, Utah
I would like to take this opportunity to discuss the need for expanded
interdisciplinary research in range. There are approximately 960,000
acres of rangeland in the United States. Eighty to ninety percent of
some western states are range. Users of range, technicians and range
scientists are being asked to produce 302 more meat and milk from range1
by 1980. The increased cost of feed and the energy costs associated
with the stockyard industry are placing renewed interest in rangeland.
One indicator of the need for intensive range research is the publication
of new range policies for the various agencies involved with the manage- •
ment of our country's grasslands. These policies completely ignore
insects as components of range systems. For example, the complete elimi-
nation of grazing on certain government lands may have disasterous
effects in view of basic ecological principles and past experience with
the soil bank. The lack of economically viable pest management alterna-
tives for range management is further evidence of the need for integrated
pest management research on range grasses.
When I began working with range insects in 1971., I soon realized how far
behind we were. Surveys indicate that some aspects of range research
and practices are about 35 years behind those of some other major crops.
Integrated range research is still in its infancy. Only isolated and
fragmented projects exist around the country. There is much to do and I
feel it is an exciting time for research in range pest management.
The impact of insects on range is poorly understood. With the exception
of grasshoppers and a few other insects, little is known about the basic
biology and life cycles of range insects. Insects are important compo-
nents of range ecosystems. Utah State University data show that a re-
latively low population of insects and their relatives consumed 2.8 AUMs
(animal units per month) while livestock and wildlife ate 2.1 AUMs on
a range in 1975. The basic data base is not yet available to develop
a comprehensive pest management program in range.
The basic research needs in range include the identification of: the kinds
and relative numbers of insects and their basic biologies found in range
grasses; the major insect pests and beneficial range insects; the
43
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economic thrasholds for various range peats; the influence of all the
vital factors of their environment; the relation of the vertebrates
and invertebrates to various plant communities and to each other; the
relation of the lifecycles of the many range grasses to the animals, other.
plants:, climate, soil, etc.; the possibilities of breeding resistant grass
varieties; and the relationships of grazing, methods of planting, etc., to
the development of insect and weed pests.
Many of the fundamental principles of range management have been de-
veloped without a full complement of interdisciplinary research. In
face, .some range policies, recommendations and practices appear to pro-
mot* insect development, serious insect outbreaks and unmeasured losses
in our ranges.
One; management practice used in Utah is to remove sagebrush by spraying:
with herbicides or burning. While this increases the available moisture.
and nutrients for grasses it also reduces the diversity of habitat for
predators and parasites. High incidence of pest outbreaks have occurred!
in some of these areas.
Another management practice to increase the amount of rangeland is chain-
ing (removing) pinon pines and juniper. One chaining technique involves
chaining the pinon and juniper, leaving the debris in place, and plant-
ing seed amoung the remaining native grasses. This technique provides-
a diversity of plant species and habitat. Another technique involves
chaining the trees, removing them, and planting an introduced grass mono-
culture. Ken Ostlie, one of our students, has found that the black grass
bug, Labapa, which is becoming a serious range pest in Utah, is 60 to 100
times more abundant in grass monocultures than in areas where the "debris
in place technique" is used. By reducing the diversity of habitat for
beneficial predators and parasites, serious infestations of range pests
can occur.
Some methods of grazing may also favor insect development. Most of the
eggs of certain insects are in the lover part of the plant and remain in
the field after grazing. If not removed by grazing the eggs are ready
to develop to their full biotic potential. The amount of plant litter in
ranges and the amount removed by grazing seem to be related to the number
of injurious insects present. Fields we have studies which have been
cleanly grazed in the fall or winter, or have been thoroughly burned,
usually have few injurious insects. Some insect eggs appear not to sur-
vive th« trip through the digestive system of certain animals. Removing
these insect eggs by grazing may help explain why the grazing systems
of some ranchers are resulting in an increased weight gain of their stock.
The cooperative efforts of ranchers, range, specialists from state and
federal agencies and Utah State University have begun to identify and try
co solve som« problems of grass production. In 1971 USU initiated its
range research and at present we have a 10 man team. Our interdisciplinary
range research team is exploring possible pest management alternatives.
Cultural and aanagment practices, as well .as chemical contol, offer prom-
ising and economical possibilities for reducing losses du* to range insects.
44
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Examples include: 1) proper planting methods, such as seeding in hetero-
culcures instead of monocultures; 2) periodic grazing by single or
combinations of animals, following the growing season, to reduce over-
wintering insect populations; 3) use of grasses resistant to insect and
nematode feeding, and, diseases; 4) burning to remove plant residues
and eggs; 5) protection and propagation of beneficial insects.
Planting resistant varieties of grasses shows great promise. Many of
the grasses that have been introduced were selected on the basis of
moisture adaptability and palatibility and have not been screened for
protection against major, pests. Currently, little is being done on
breeding grass resistance but in the few tests we have conducted, it looks
like there is great resistance material available. In Utah there are at
least 300 species of range insects many of which are beneficial. There
are encouraging possibilities for biological control in range.
One important means to developing sound range management is to develop
interdisciplinary curricula in our educational institutions. Students
don't have the foundations to adequately approach the problem from an
integrated perspective. We have to give students & broader understanding
of ecosystems. Unfortunately, our educational system is still structured
to provide students with only a small specialized piece of the entire
picture.
As with other new approaches, one problem we face is Che legitimacy
of interdisciplinary range research. Tackling this involves getting the
right information to all government levels in order to get the necessary
support for this type of research. There has to be good communication
between researchers and state and federal agencies to avoid duplication
of effort and to combine our resources in solving problems of mutual
interest.
Although much remains to be done in basic range research and the develop-
ment of control alternatives, we are not starting from zero. Many princi-
ples and procedures developed in other crop studies, such as alfalfa,
will be applicable but Che specific details related co grasses will need
to be established. It will be exciting co study the basic biologies of
range insects to build a panorama of the wildlife and plants, and co
put them all together into an integrated system.
Someone said a good idea doesn't care who has it. We hope the agricultural
research capability of che country will pick up on range IPM as it has
on ocher crops. It was said recently in a meeting in Sale Lake City.that
it seems coo often we don'c have cho money Co do things right che first
time, but we usually seem co find che money co do things over again. We
hope chere is a way Co get enough financial support to develop pest
management correctly for range grasses the first time.
-------
Part One
Overview
-------
Part Three
Control Strategies
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BIOLOGICAL CONTROL BY NATURAL
Robert van den Bosch
Division of Biological Control
University of California
Albany, California
BIOLOGICAL CONTROL is simply the regulation of plant and animal numbers
by natural enemies. As such it is a natural phenomenon, one of a
spectrum of physical and biotic forces which collectively maintain through
a balance of nature, the mechanism of natural control. Natural control
is vital to life on earth, for it is the phenomenon that permits the
co-existanc« of the planet's myriad species. Biological control, then,
as a major factor in the balance of nature, is of immense importance to
us .
In assessing the phenomenon of biological control, it can be viewed in
three major aspects: 1) Its naturalistic dimension, 2) the classic im-
portation of natural enemies, 3) the preservation and augmentation of
natural enemies.
This discussion will be restricted essentially to an overview of the
biological control of pest insects and weeds, and will emphasize the
role of predators and parasites in biological control with only passing
mention being made of pathogens. Pest pathology (including microbial
control) is an immense subject in itself and cannot be given justice in
such a brief discussion as this.
Again, it is emphasized that biological control is an extremely important
natural phenomenon that is constantly going on all around us. It is
effected by a stupendous range of natural enemies against a vast array
of host (victim) species. This can perhaps be best visualized by con-
sidering the host-natural enemy interaction in its two extremes; on the
one hand, predation by the sperm whale on pelagic squid, on che other,
victimization of a bacterium by a bacteriaphage. Between these extremes
lie che countless predator-prey, parasite-host, pathogen-host interrela-
tionships of nature.
It is perhaps best at chis point to define a few terms that are commonly
used in a discussion of biological control. These terms are:
parasite; a small organism that lives in or on a larger host organism.
parasitoid; a parasitic insect that lives in or on, and eventually
kills, a larger host insect (or other arthropod).
pathogen: a microorganism that lives and feeds (parasitically) on
or in a larger host organism, and therby causes injury
to it.
predator; an organism that feeds upon other species (animal or
plant) chat are either smaller or weaker Chan itself, or
(in the case of plants) lack mechanisms of resistance
or colaranc* co it.
49
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NATURALLY OCCURRING BIOLOGICAL CONTROL
In pest control evolution tho past third of this century is known as
tho synthetic organic pesticide era. The record shows that during
this period there was a massive increase in pesticide use, to the extent
that in many of the world's centers of agricultural (and other resource)
production, as well as in disease vector control, the chemical control
strategy has prevailed. But this strategy is falling short of expecta-
tions, and there is an increasing trend to integrated control (integrated
post management). One of tho key factors that has crippled the chemical
control strategy has been its adverse effects on naturally-occurring
biological control. This has led to & global syndrome, termed by some
tho Pesticide Treadmill, which is characterized by frequent target pest
resurgences, secondary post outbreaks, and pest resistance to pesticides.
As a result it is questionable whether we have made gains against tho
posts sinco tho mid 1940'3, and in fact with insects there is evidence
that wo have lost ground.
Despite tho troubles associated with the chemical control strategy there
are some positive aspects to the debacle. One is the realization that
biological control as a ubiquitous natural force is an extremely impor-
tant 'asset to us in our never-ending competition with pest organisms,
and that it can be built into, and indeed must bo a pillar of the emerging
integrated control strategy.
All ecosystems, even crop monocultures, contain food chains and food webs
in which carnivorous and herbivorous species (predators, parasites and
often pathogens too) restrain or completely suppress pest or potential
pest species. Common sense dictates that we take full advantage of
this bonus mortality in our pest control strategy, and this is what is
being increasingly done under integrated control. Every integrated
control program of which I am aware has had a major biological control
component. This component occurs as naturally-occurring biotic mortality.
In this connection there is no question in my mind that in our future
employment of biological control the greatest emphasis will be on the
utilization of naturally-occurring predators, parasites, and pathogens.
In face, as emphasis on integrated control research has Increased, there
has been an immense amount of study on naturally-occurring biological
control. It is impossible to adequately treat these studies in this
short presentation; however, in an attempt to give some impression of
the range, diversity and importance of naturally-occurring biological
control in pest management, I have tabulated a number of successful in-
tegrated pest management programs, and have noted in a very superficial
way, the kinds of natural enemies involved (See Table 1).
CLASSIC NATURAL ENEMJf INIRODUCTION (Classic biological control)
Classic biological control is largely directed against accidental invaders
of new areas which attain epidemic abudancc because of cheir escape from
che natural enemies that restrain them in their native habitacs. There
arc some rare exceptions to this, but the overwhelming number of successes
30
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3
20 o
Coeeon
Alfalfa
?aar
Soybean
Vhaae
Oil ?ala
Taa
Ciema
vafaeaeio
Moaquieoaa
Uacalier
Para
Calif omia*ii OSA
PonurylTani*, USA
Heva Scoela (Canada)
CalifontU, USA
Midveae and Soucaaaac OSA
CMla
XaUyila
Sri Uaka
ZJHTS^X
Ca^ | ^ f OTTlt-Kt ?3A
California, OSA
(Maria Couney)
Trpa at oaeural «n«ar
ganaraliat pradaeora md paraaleaa
gotaraliac pradacors
pradaeora, paraaieaa, paehofana
prtdaeorjr aieea
pradaeorr mieaa
apldar aiea faodiaj ladyb«aelaa
pradaeora aad paraaieaa
pradaeora
pradaeora, paraaieaa, paehofana
pradaears, paraaieaa, pachofana
pradaeora, paraaieaa, paehofana
paraaieaa
pradaeora, paraaieaa
pradaeora, paraaieaa
pradaeora
'Table 1 Examples of integrated control programs with impor-
tant biological control components.
in classic natural enemy introduction have involved the re-association
of invader pests with their adapted natural enemies obtained from the
areas of indigeneity.
Classic biological control involves three basic steps: (1) identification
of che pest's native home (this, of course, involves correct identifica-
tion of the pest itself), (2) a search in the native area for the pest
and its natural enemies, (3) shipment of che natural enemies co che
invaded area and after appropriate quarantine processing and biological
31
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testing, mas$ production, and colonization of these natural enemies in
the field.
Aa was earlier indicated, the goal of this process is to re-establish
the host-natural enemy relationship, and in doing so to lower the pest's
long-term population level so that the species is reduced in severity
or entirely eliminated as a pest. It is important to note that imported
natural enemies do not eradicate their hosts. Instead they drive the
host numbers down to and maintain them at reduced average densities.
If the average is low enough the species remains below the economic,
aesthetic or public health threshold and is no longer a pest. The
question often arises,"What happens to the natural enemy when its host
becomes scarce? Does it then attack other animals and crops and become
a post?" The answer, of course, is "no", because the natural enemy
density dependent and most often specifically locked to the host pest.
Thus it wanes in abundance as its host's numbers diminish, and becomes
rare too, but with the capacity to regulate its host at a very low
population level.
Worldwide, natural enemy introductions have resulted in substantial to
complete control of slightly over 100 pest insects and about 20 weed
species. This cay appear to be a very poor record when measured against
the earth's thousands of pest insect and weed species, but it must be
noted that control by imported natural enemies is permanent. In this
sense it is one of our most successfully employed pest control tactics.
The natural enemy introduction tactic does have its limitations, parti-
cularly in that it has little potential against native pests (i.e.,
insects and plants that become pests in their native habitats). And
even against exotic pests, it is not always possible to effect satisfactory
biological control because of ecological, biological, administrative,
technical, and logistical limitations or encumberances. Furthermore, the
tactic* has also been grossly under-exploited as evidenced by the fact
that it has been utilized against only about 225 of the world's 10,000
or more pest insects; in many of these cases the programs were poorly
conceived and conducted. Nevertheless, classic natural enemy importation
has been one of our most successful tactics in effecting permanent pest
control, and it has considerable potential for additional success.
BIOLOGICAL CONTROL OF WEEDS
The great majority of classic biological control successes have involved
insects. However, the tactic has been successful against weeds too. In
principle there is little difference between biological control of insects
and weeds: (1) Both involve natural enemies; e.g. weeds (predators and
pathogens), insects (predators, parasites and pathogens). (2) Successes
with imported natural enemies have been overwhelmingly against alien
(exotic) pests. (3) Both techniques offer safe, effective, long term
control at low cost. (4) Control does not result in pest eradication.
But there are important differences between the two practices. With
weeds, there is an absolute necessity that the natural eneay be highly
52
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specific, preferably monophagous^and at most very narrowly oligophagous.2
There can be absolutely no possibility that the introduced enemy will
develop an affinity for some cultivated or otherwise highly valued plants.
On the other hand with entomophagous insects, oligophagy or even poly- •
phagy may sometimes be advantageous, and there is certainly no stipula-
tion that an imported parasite or predator be narrowly specific. The
basic concern is merely that no beneficial insect (e,g. the honey bee.
some native pollinator, lady beetles, lacewings, etc.) be adversely
affected, or that hyperparasites be imported.
The need for specificity in weed feeding insects places an inordinate
burden of responsibility on everyone involved in the importation pro-
cess, particularly those who do the testing. In practice the candidate
insect (or pathogen) is first intensively tested overseas in the
collecting area. In this connection, all agencies which are seriously
involved in weed biological control, maintain overseas laboratories
(i.e., United States Department of Agriculture, Commonwealth Institute
of Biological Control , Australia, and University of California). Test-
ing involves wild plants related and unrelated to the weedy target and
a wide range of related and unrelated commercial plants. The overseas
testing establishes whether a species will be passed on to the domestic
quarantine facility for additional intensive study and testing. Then,
even after this second set of screenings is completed, the data are
reviewed by a special committee of experts who make the final decision
as to whether the natural enemy shall be cleared for field release.
The suppression of weedy plants by imported natural enemies differs some-
what from the suppression of pest insects. With insects, suppression
usually results directly from premature mortality produced by the natural
enemy. But with weeds the role of the natural enemy is more complex.
(1) It may simply kill the plants. Here the timing of attack (e.g.,
at a time of nutritional stress) may be as important as massive defolia-
tion. (2) It may act as an intermediary for some pathogen (e.g., as
occurred with prickly pear in Australia). (3) It may destroy the repro-
ductive capacity of the weed (i.e., seed feeders). (4) It may simply
impair the weed's competitive capacity, so that it is displaced by more
valuable species.
But despite the technical and subtle mechanical differences just des-
cribed, biological control of insects and weeds operates under the same
broad principles. At the heart of the matter is the phenomenon of
reciprocal density dependence.
Biological control of weeds can be considered in the same three basic
aspects as biological control of insects, or other animal species: (1)
the naturalistic, that is, the broad phenomenon of plant species under
regulation by natural enemies, (2) the classic introduction of natural
enemies as discussed above, and (3) the augmentation and conservation of
natural enemies. However, the latter is less applicable than with insects.
In fact, outside of the use of pathogenic spores as exemplified in
northern joint vetch control in rice, it is difficult to cite an aug-
mentative practice utilized in weed biological control, unless it is the
Ihost range a single species. 2rescricted to a few related species
53
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us* of selective pesticides to protect a natural enemy, or re-inoculation
of an area with an enemy agent.
Several factors bear on the consideration of a weed's suitability for
biological control and here again, in part, there are differences from
insect control. These factors are:
1. Whether the plant is native or introduced.
2. Whether the weed has close relatives that are of economic or
aesthetic importance.
3. Whether the weed occurs in a disturbed (short crop) or stable
situation.
4. The viewpoint of various groups as to the plant's harmfulness
or value.
In other words, what is one man's weed is another man's resource: e.g.,
Johnson grass has some forage value; saltcedar is considered a weed by
growers, but to fish and game people and hunters, it is a good thing be-
cause it serves as a nesting place for doves; yellowstar thistle is con-
sidered a pest by stockaen but an asset by fish and game people and
apiarists.
These conflicts should be kept in Bind. In working out the cost-benefit
balance of a program it is important to remember that biological control
of weeds doesn't eliminate (eradicate) the plants, and so it is possible
to have aattars both ways. Thus, conceivably, under biological control
the virtues of a plant can be retained while its disadvantages are
suppressed.
Biological control of weeds cannot simply result in the exchange of one
weedy species for another. Thus, a program might have to entail intro-
ductions against two or sore weeds if true benefit is to be realized.
Insects.have been the major natural enemies used against weeds, but other
organisms have been successfully employed. For example, fish have been
used against aquatic weeds and geese against certain terrestrial weeds.
Several pathogens have been used for weed control, as have mites and
nematodes.
PRESERVATION AND AUaSNIATION OF NATURAL ENEMIES
Modern pest management as it shifts to the' integrated control strategy
increasingly incorporates and optimizes biological control. The addition
of new natural enemies into crop or other resource systems by the classic
importation of exotic natural en*e»ies is one way in which this is done.
But it is important as well to preserve or augment natural enesiies that
already exist in a resource environment, and this can be dose in a. number
of ways. One way to do this is by periodic innoculative or inundative
colonization of insectary reared natural enemies in the field. In th«
past there has been considerable question as to the usefulness of this
technique. Mass release of the egg parasite Triahograrrmz in such crops
as sugarcane, cotton, corn and apple has been especially suspect. On the
54
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other hand, very successful programs of mass release of a variety of
natural enemies against citrus pests by California's Filmare Citrus
Protective District, releases of several kinds of natural enemies against
glasshouse pests in Europe, and release of parasites against the Mexican
b«an beetle in soybean in the Southeast USA indicates that the periodic
colonization tactic can be effective and economical. Obviously the
matter needs further study and development.
A variety of cultural manipulations have been employed or proposed as
means for preserving or augmenting natural enemies. For example, nectar
plants have been used to provide a food source for adult parasites. Strip
harvesting of alfalfa has been effectively used in California to enhance
biological control of aphids and lepidopterous larvae. Also an California,
cover crops have been used in almond groves and vineyards to favor pre-
dators of spider mites. Again, in California, it has been shown that
planting of blackberry (Eubus sp.) adjacent to vineyards increases the
effectiveness of the parasite of the grape leafhopper. In this case the
grape leafhopper passes winter in diapause, but its parasite does not
and therefore must find an alternative host to survive. This host is
a species of leafhopper that occurs on blackberry. Thus, by ;pIanting
blackberry near vineyards, a population of the grape leafhopper parasite
is maintained and is available for early invasion of the vineyard each
spring.
Currently, there is considerable interest in nutritional augmentation of
natural enemies, and in the use of kairomones (cue chemicals), to enhance
their effectiveness. Results of limited testings have been very pro-
mising. But these aspects of natural enemy manipulation are still very
much in the research phase and are not now claimed as being effective
practical tools.
»
Without question, the most important area of natural enemy preservation-
augmentation lies in the selective, discriminate use of chemical pesti-
cides. Of the many integrated control programs now in effect worldwide,
selective use of pesticides has been an important element in-virtually
every one. As the integrated control strategy comes into wider imple-
mentation, the selective use of pesticides will almost certainly become
more widely, indeed almost routinely, used in pest management practice.
i
THE FUTURE OF BIOLOGICAL CONTROL
Biological control has a future, because as a natural phenomenon it will
continue co act upon pests whether we recognize this role or not. But,
of course, since we are increasingly recognizing it and incorporating
it into our pest management strategy, biological control will inevitably
play a more important role in pest control as time passes. In all probabil-
ity, naturally-occurring biological control will recieve our major
attention, but classic natural enemy importation will also receive in-
creased emphasis. As our knowledge of, and techniques in, natural enemy
preservation and augmentation increase in depth and sophistication, bio-
logical control will become a much more effective pest management tactic.
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DISCUSSION . .
QUESTION: Save natural enemies from closely related pest species been
used in biological control programs?
VAN DEN BOSCS: lea, but first we go the easy route by looking for con-
trol agents associated with the pest species. There have been several
cases where natural enemies from related species have been introduced
and established in the field. The coconut moth from one of the Pacific
Islands is one example where a parasite was obtained from another species.
However, the overwhelming number of cases have used parasites obtained
from the pest species in its native habitat.
QUESTION: Are entomologists looking at the possibilities of breeding
insecticide resistance in parasites and predators?
ri
7AN DM BOSCH: Marjorie Soy, who is now at Berkeley, is working on
deliberately developing and selecting strains of predatory mites in
the laboratory for use in integrated control programs in heavy pesticide-
use systems. Stan Soyt in Washington state discovered that Metaseiulus
occidentalis had a tolerance for organophosphate insecticide's". This was
a real breakthrough in the spider.firite IPM program on apple because Stan
was able to incorporate that tolerance into the program.
COMMENT: I think it is wonderful that testa ore being mode to breed
or select predators and parasites that are resistant to chemicals used
in certain aystems, but I think one should not let that obscure one's
view of the total system. It is never simple in a biological system and
it isn't usually a matter of Just one parasite or predator. Too narrow
a focus obscures the view that what you really want is a lot of natural
enemies in the control zone.
VAN DEN BOSCH: ?es, maybe if we understood the entire system, we would
find out that some of these problems would solve themselves. I have
recently reviewed some data on forest entomology dealing with the tussock
moth and the spruce budworm, pests of massive economic impact and tre-
mendous public concern, lou begin to understand why the "tussock moth
is becoming a more important pest; it is because of the way we are har-
vesting the forests. Under this program the forest is shifting ewer to
a fir type, a monoculture, and under this situation the tussock mcth
population goes wild. lou can go in and spray but, unfortunately, we
have developed a nursery for the tussock moth. In a sense this is what
has happened with the balsam fir and the spruce ,budworm in the northeast.
Here we have protected over-mature trees and turned the forest into a
perennially susceptible environment. Ve have to look at these systems
in their entirity. h'e have to look at the resource, its total relation-
ship'with the environment in which it grows, and utilize that environment
in every way we can to help us get maximum yield or qualiry out of the
resource, finally, if necessary, we have to use our artificial ^eans,
whether biological, chemical, genetic or cultural, in a very intelligent way.
56
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REFERENCES
DeBach, P. 1974. Biological Control by Natural Enemies. Cambridge
University Press, 321 pp.
DeBach, P. (Ed.). 1964. Biological Control of Insect Pests and
Weeds. Chapman and Hall, London, 344 pp.
Franz, J.M., and A. Krieg. 1972. Biologische SchHdlings-bekaopfung.
Pavey, Berline, 208 pp.
Hagen, K.S. and J.M. Franz. 1973. A history of biological control.
In "A History of Entomology." (R.F. Smith, I.E. Mittler and C.N.
Smith, Eds.), pp. 433-476. Annual Reviews Inc., Palo Alto, Ca.
517 pp.
Huffaker, C.B. (Ed.). 1971. Biological Control. Plenum Press, New
York and London , 511 pp.
Huffaker, C.B., and P.S. Messenger. 1977. Theory and Practice of
Biological Control. Academic Press, New York, San Francisco,
London, 788 pp.
van den Bosch, R. 1971. Biological control of insects. Ann. Rev.
Scot. Syat. 2:45-66.
van den Bosch, R., and R.S. Messenger. 1973. Biological Control.
Intext, New York, 180 pp.
57
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OJUEUKAL CONTROL
Theo F. Watson
Department of Entomology
University of Arizona
Tucson, Arizona
INISDDUCTICN
The concept of integrated pest management (IPM) has gained recognition
and acceptance only in recent years. However, varying levels of pest
management have been practicad on a localized basis for a long time. The
methods available for combating pests have increased in numbers along with
the evolution of intensified agriculture in this country. Today, a suffi-
cient number of control tactics are available to permit a more flexible
and satisfactory approach to pest control. This can be accomplished by
integrating these options, each of which imposes an additional repressive
effect upon pest'populations, into a compatible and harmonius system. Among
these components of an IPM system is cultural control, the topic for dis-
cussion in this paper.
The term cultural control is so broad and all inclusive that a definition(s)
is germane at this time in order to unify our thinking on this subject.
Watson et al. (1976) have defined cultural control as the use of farming
or cultural practices associated with crop production to make the environ-
ment less favorable for survival, growth, or reproduction of pest species.
In addition to che direct repressive effects of cultural practices on
insect (or other) pests this definition encompasses che effects of other
control methods such as biological control as they are influenced by en-
vironmental change. For example, since biological control agents such as
predators and parasites are a part of the environment, any practice that
alters the environment to the enhancement of beneficial species would re-
sult in an additional repressive effect upon pest species. The National
Academy of Sciences (Anonymous 1969) publication on Insect-Pest Management
and Control states that the principle involved in the cultural control of
insect pests is purposeful manipulation of the environment to make it less
favorable, thereby exerting economic control of the pests or at least re-
ducing their rates of increase and damage.
In a more natural setting such as our forests or wildlife preserves, the
terminology generally used is habitat management or environmental manage-
ment. In a sense, this is analogous to cultural control in our agro-
ecosystems. Komarek (1969) defined environmental management in its
broadest sense as the intelligent control and direction of the factors
affecting biological organisms. He further points out chat che founda-
tion for such direction is the study of the relationships of living
59
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things co choir environment and Co each other - ecology. As with tho
biological control method, cultural control rests heavily upon ecological
principles.
This method of control, or better still, management, is aimed primarily
at preventing post damage. Practices generally must be employed veil
in advance of the expected problem to achieve that effect. This requires
an intimate knowledge of the biology and ecology of the pests involved,
including their relationship to their host plants and to other biological
organisms in tho system.
Tho goal of cultural control, then, is to reduce pose populations to levels
sufficiently low to prevent economic damage by the use of appropriate
cultural practices. The practices, however, must bo compatible with other
aspects of the ecosystem such as optimum crop production. They should pro-
vide no benefit to other pest species and at tho same time little or no
detriment to beneficial species. This goal is definitely compatible with
tho modern philosophy of post management.
Tho cultural control method possesses certain advantages as wo.ll as dis-
advantages over other control methods. Among tho advantages are economy
and non-disruptive effects. In many instances there is no additional
outlay for equipment or operations. . Tho effect can be achieved merely by
altering tho timing or procedure of an operation which would have boon
done anyway. Additionally, most cultural practices can be performed
without tho detrimental side-effects on beneficial species that generally
follow tho use of insecticides.
The major disadvantages of the cultural method are: practices need to be
performed long in advance of the problem and the measures do not always
provide compote control. Both of these, particularly the first, point
to the need for a chorough knowledge of the insect's life and seasonal
history and its habits, including host and habitat preferences. These
disadvantages are gradually losing significance, however, as more know-
ledgeable pest management specialists are becoming directly involved in
pest management programs on a continuing basis. They assist the grower
in long-cerm planning aimed at preventing pest problems in addition to
seeking immediate solutions to already-existing ones.
There are certain key considerations chat must be taken into account in
any decision to utilize cultural practices as a means of coping with pest
problems or even to utilize them as a component in an insect post manage-
ment system. Those key factors are: adequate knowledge of the biology
and ecology of tho post, diversification of the cropping system, and
availability of alternative control methods.
In general, a thorough knowledge of tho pest's life and seasonal histories
and its behavioral characteristics is necessary to effectively employ
cultural practices for its control. Tho more that is known about a
species, cho grantor is the likelihood that a weak link in the pest's
biology can bo utilized to develop cultural control techniques.
Diversification of the agroecosysterns will determine to a large extent
the toptions available for designing cultural control strategies based on
60
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the pest's biology and ecology. For example, because of the crops grown
in the system, rotations nay be ineffective due to the absence of the
crop necessary to break the seasonal cycle of the pest. Alternative con-
crol measures, for example, chemical control, may make cultural control
less appealing and perhaps less profitable for the short term. However,
in the long term cultural control may be far more advantageous when con-
sidering the side effects that generally follow chemical control alone.
In such a decision the grower must weigh the costs/benefits as a result
of using the different methods against expected long-term effects.
Relative to a discussion of specific cultural practices, and as a matter
of convenience, I will subdivide this topic into three broad categories:
crop management, soil management, and water management. Various options
available under each of these broad headings will be discussed.
CBDP MANAGEMENT
Crop management provides an environmentally sound, effective and economical
way to manage many of our major agricultural pests. Crop management prac-
tices can be employed to disrupt the life or seasonal histories of certain
pests, to alter the microclimate creating a less favorable habitat, to
permit escape from damaging infestations, or to utilize behavioral
characteristics preventing damage to specific crops.
There are a number of ways of achieving one or more of the above through
crop management. Among these are: crop rotation, planting or harvesting
practices, crop diversification, and trap crops.
Crop Rotation.
The basic principle involved with this cultural practice is the alterna-
ting of susceptible with non-susceptible crops to prevent the buildup of
damaging infestation levels. Generally, pests having relatively long
life cycles are the ones more effectively controlled by rotation. Control
by this method does not require an exact knowledge of the life and seasonal
history (Isely 1946) but does require an accurate knowledge of habits,
particularly feeding habits.
The northern corn rootworm, Diabrotiaa tcngicornia (Say) is an excellent
example of an insect that can be effectively controlled by rotation.
This insect has a one-year life cycle (Metcalf at al. 1962) and the larvae
must feed upon corn roots in order to reach maturity. Therefore, if any
other crop follows corn the life cycle is broken and no damage occurs.
Damage almost never occurs unless land has been planted to corn for at
least two consecutive years.
Planting and Harvesting Practices
Planting practices can be used effectively in a number of ways to prevent
damage from insect pests. The classic example involves a precise plant-
ing date for winter wheat to prevent infestation by the Hessian fly,
61
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Mayetiola destructor (Say). This is based on an intimate knowledge of
the insect's biology. Adult flies emerging in the fall live for only
two to three days. Therefore, wheat sown late enough so that the
plants have not come up before the fly emergence period will escape in-
festation. The proper date of seeding wheat to escape infestation by
the fall generation of Hessian fly was worked out by entomologists in
the experiment stations of all the principal wheat-growing states (Metcalf
et al. 1962). As a result, fly-free dates have been established for
various zones in the North Central states.
Another example of the importance of planting dates pertains to grain sorghum
in Arizona. Sorghum is attacked by the sorghum midge, Contfsrinia ear-
ghicola (Coquillect), which feeds upon the developing seed. Usually an
economically damaging infestation does not occur until the fourth genera-
tion. Therefore, early-planted sorghum will reach maturity ahead of the
4th generation and escape injury. Another important cultural practice
is to control Johnson grass, an important alternate host, near sorghum
fields (Garhardt and Moore 1962).
Harvest dates and practices are also important options in managing key
pest problems. The harvest date of the first alfalfa cutting in the spring
may b« altered slightly to prevent serious, damage by the alfalfa weevil,
aypera. postioa (Gyllenhal). Bishop et al. (1978) stated that harvesting
the first crop of alfalfa before damage by the alfalfa weevil becomes
severe prevents or delays the need for insecticide treatments in Idaho
and Utah.
In the agroecosystea, the primary host of lygus bugs is alfalfa, on which
populations increase to large numbers during the summer (Stern 1969).
In most areas of the southwestern and western part of che cotton belt,
both alfalfa and cotton are grown in large acreages. Lygus is a key pest
of cotton and the problem on cotton is directly related to the practice
of harvesting large blocks of alfalfa at one time and forcing the lygus
over on the cotton. Stern et al. (1964) reported a strip-cutting system
that provided two growth stages of alfalfa in the same field at all times.
This reduced lygus emigration into cotton to the point where insecticide
applications for lygus control were unnecessary.
Hakickas and Watson (1974) compared seasonal population fluctuations of
adult and immature lygus and 7 predaceous'arthropod groups, before &nd
after cutting, in strip-cut alfalfa (Figure 1). In addition to the
herding of lygus back and forth within the alfalfa field throughout the
season, of particular significance was the maintenance of large predator
populations for the entire season. Van den Bosch and Stern (1969) have
reported on the effects of strip-cutting on other arthropods in alfalfa.
Their results showed a general upward trend of predator populations in
strip-cut fields as compared with a leveling off of populations in solid-
cut fields. lu addition, in the strip-cut fields the several predator
specie* studied showed much less violent population fluctuations ehoc
they did in the solid-cut ones.
62
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600
co
Q.
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Satigmene ocreo. (Drury), nay build up on cotton. Generally, it is so late
that insecticidal control for the insect on cotton is unnecessary. However,
fall lettuce planted adjacent to such a cotton field is vulnerable to the
masses of migrating larvae as they leave the cotton. Some separation be-
tween such crops would alleviate this problem, even though other satis-
factory control measures are available to protect the lettuce, e.g., a
foil barrier around the lettuce field to prevent the migrating larvae
from entering the field.
Bishop et al. (1978) stated that diversity resulting from the "dirty field
technique"(allowing noncrop plants to survive rather than using clean
culture) has a similar stabilizing effect on the agroecosystem. Diversity,
however, may not be the most efficient and economical short-term method
of crop production.
Trap Crops =
Trap cropping is simply the planting of a nore favorable host crop in the
system to attract the pest and prevent it from attacking a more valuable
crop. This requires a general knowledge of the life history of the pest
and, more importantly, an intimate knowledge of host preferences of the
pest.
In the South, prior to the availability of organic insecticides to control
the bollworm, HoliothLa zeo. (Boddie), on cotton, trap cropping of this
pest was relatively common. This involved planting small acreages of corn
in the vicinity of cotton fields so that silking corn vas available for
oviposition by the bollworm moth during the major fruiting period of
cotton. For season-long protection, this required a succession of plant-
ings at two-week intervals (Isley 1946). It should be pointed out, however,
that unless properly implemented this can backfire by sustaining large
pest populations that would go to cotton if silking corn were unavailable.
SOIL MANAGEMENT
Soil management may be useful in minimizing pest problems for chose pests
that pass at least part of cheir life cycle in the soil. This may also
be closely allied with the cropping system and the rotation scheme. The
sand wireworm, Horiatonotua uhlerii Horn, is an example of a acacias whose
importance as a pest depends more upon the type of soil in which it lives
than any other factor (Isley 1946). Changes in the crops grown would
have little direct effect as this pest is a general root feeder and would
thrive on a wide variety of crops. However, a crop that would add a
significant amount of humus to the soil, and thus increase its water hold-
ing capacity, would aid in control. Soil management is most effective
for control of this pest where the land can be fallowed for one or more
years or where crops are grown that require no cultivation and are not
attractive to the beetles during the period of oviposition. This could be
accomplished with such crops as oats,;grapes or clovers.
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WATER MANAGEMENT
Water management offers a great opportunity to adversely affect a
variety of pest problems, ranging from agricultural pests to those
directly affecting human welfare. From the agricultural standpoint this
is particularly true in the arid regions of the world. Since most in-
sects have a rather narrow range of tolerance for moisture, there is the
opportunity to either reduce the moisture level below the tolerance level
or to provide an excess to raise it above the tolerance level. Research
has shown that the pink bollworm, Peatinophora gosaypiella (Saunders),
requires an optimum level of moisture for overwinter survival, above or
below which results in greater mortality (Slosser and Watson 1972a).
Probably one of the most striking examples of controlling a post with
water management, and one with which we are all familiar, is drainage of
standing water to eliminate a mosquito problem.
There are many other techniques, or modifications of those already dis-
cussed, that are classified as cultural methods and can be used effective-
ly in localized situations. Some of these are: sanitation, destruction
of crop residue, flaming or burning and elimination of alternate hosts.
The use of resistant host plants should also be mentioned since it is
sometimes classified as a cultural practice. Others, however, consider
it of such importance that it is elevated to the status of other majoi
control methods. Where available, the use of resistant varieties is
one of the most convenient and effective methods of pest control. The
development of alfalfa varieties resistant to the spotted alfalfa aphid,
Therioaphia ma.cn.lata (Buckton), provided a most satisfactory solution
to a very serious pest problem.
DTTEGRATION OF CUETUBAL PRACTICES TO ENHANCE PEST MANAGEMENT
It is unfortunate that when we think of cultural control, we usually tend
to rely upon a single practice to solve the problem. In reality, however,
there may be a number of cultural practices, each of which provide a
segment of control resulting in overall satisfactory suppression. This
is the case with the pink bollworm on cotton in the Southwest and in
Texas where essentially a combination of practices resulted in effective
cultural control of this pest (Adkisson and Gains 1960, Nobal 1969).
Adkisson and Gaines (1960) listed the primary practices as follows:
1. Defoliate or desiccate the mature crop to cause all bolls to
open at nearly the same time, expediting machine harvesting.
2. Harvest the crop as early and in as short a time as possible.
3. Shred stalks immediately following harvest.
4. Plow stalks under immediately, preventing regrowth of new frating
forms that might provide food for diapausing larvae.
5. Prepare land for planting of subsequent crop, including pre-
plant irrigation in arid areas.
6. Plant new crops during a designated planting period that allows
for maximum "suicidal emergence" of moths from overwintering
larvae.
65
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The> combination of practices developed in Texas provided' th» growers1 with
a control program for the pink bollworm 30 successful that insecticides
are seldom needed (Adkisson 1972). '
During the. past several years research has been conducted in Arizona on
cultural control of the. pink bollworm. The primary objective has been
to reduce overwintering populations of diapausing larvae, to levels suffi-
ciently low to prevent economic infestations during the subsequent grow-
ing season.
A large amount of data showing the effects of various cultural practices
on overwinter survival and spring moth emergence- has been- accumulated-
(Watson and Larsen 1968, Watson et al. 1970, Slosser and. Watson. l»72bv
Watson et al. 1974). These data have shown that with each additional
practice imposed on cotton, such as discing following shredding, plowing
following discing, etc., there is an additional reduction in paring moth
emergence (Figure 2). With the long growing season and mild winter
conditions that occur in Arizona and regardless of the type of cultural
Shred
15
Moths/Acre
Thousands
10
TOTAL
NON- .
SUICIDAL
Mesa 1967-68
Shred Shred
Disk Disk
Plow
Ell IF
ill H:
I
Shred
Disk
Roto-
till
Shred
Disk
Roto-
till
Re-Roto-
till
M«cg* «ft«r coetoa Jrule it iv«il*bl« far
Figure 2 Effect of additive cultural practices on spring moth
emergence.
66
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practices used, overwinter survival and spring moth emergence are still
too great to prevent economic infestations during the next growing
season. The best results have been through shortening the growing sea-
son by earlier plowdown dates. These results showed that progressively
higher moth populations emerged the following spring with each delay in
plowdown date (Watson et al. 1974) (Figure 3). Essentially the same re-
sults can be achieved by earlier crop maturity without regard to when the
cottorn is harvested and plant debris plowed under. This utilizes know-
ledge of the biological phenomenon, diapause, to prevent build-op of
overwintering populations. In Arizona the incidence of diapause in the
pink bollword is low until the last week of September, at which time it
increases rapidly (Watson et a., 1976). Therefore, cotton that has attained
the stage of maturity, where most of the green bolls are three weeks old
by the last week of September, is incapable of building large overwinter-
ing populations.
20000
15000
u
CO
.c
u
s
-------
Previously, the general assumption has been that early crop termination
would result in lower yields. However, research conducted at Che Yuma
Valley Agricultural Experiment Station of the University of Arizona
has shown little, if any, decrease in cotton yields when irrigation was
terminated from August 1 to 15 as compared to termination in late September
(Jackson and Carasso, unpublished data).
The objective in shortening the growing season is to preclude the de-
velopment of large overwintering populations and thus eliminate or reduce
the need for insecticidal contol of the pink bollwora during the next
growing season.
In 1971, a 3-year experiment wao initiated at the Yuma Station to determine
the effects of various irrigation termination dates and levels of pink
bollworm control on cotton yields and overwintering pink bollworm popu-
lations as measured by sping moth emergence.
This research demonstrated conclusively that shortening the growing
season by proper managment of irrigation water was the key practice in
establishing an effective cultural control program against the pink
bollworm. Additfonal cultural practices such as discing and deep plow-
ing should be used to complement the effects of shortening the growing
season. The earliest termination date, mid-July, proved to be too early
and significant yield losses occurred. However, yields obtained from
the three remaining termination dates, ranging from about July 29 to
September 12 were comparable (Table 1). Of major signifcance was the
effect of crop termination on moth emergence the following spring.
Ttrain*clou Ofttu tf^fii Ibi« Sott Cgcgoa/Ploe aaj Scat* Slg» (*Q3)
1971 1972 1973 1971 1972 1973
July 13 July 17 July 10 37.3* 33.4 a.a.3 33.4a
July 29 Au». 4 July 31 37.3b 38.4 67.2b
Au«. 16 Au|. 23 Auf. 21 52.51) 40.5 63.3b
S«pc. 3 S
-------
The early August termination dace resulted in low spring moch emergence,
comparable to that from the aid-July termination date, but with higher
yields. From the last two termination dates high numbers of moths emerged
the following spring, indicated 'that the longer growing season provided
adequate food at the critical time when diapause induction occurred
(Slosser and Watson 1972b, Watson et al., in press). An example of the
effects of irrigation cut-off dates on spring moth emergence is shown >
in Table 2.
Irrigation
Cue-Off D*e«
July 17
Am. 4
Ku4. 22
S«pc. 7
1 Tiald* la MI
diff««ne.
Muui Tie, Moths/Acre and Seat. Sla. (.OS)1
tsMdlac* Plowing
873*
1.373*
3,938b
13,917b
M colm foUow«d by conDoa
D«lay«4 flowing Coabiaad
623*
1.250* 1,
6.917b 6.
18,417e 16,
Iteetrs »r« not ilgnlficincly
730*
313*
4Mb
167c
Table 2 Effect of irrigation cut-off and post-harvest plowdown
dates in 1972 on pink bollworm noth emergence in 1973
(Means of 3 treatment levels) Yuma, Arizona.
The utilization of production practices to shorten the growing season
while maintaining yields resulted in a conservation of irrigation
water, a decrease in insecticide usage, and a reduction in overwintering
pink bollworm larvae. This, coupled with otherpost-harvest cultural
practices such as stalk-shredding, plowing and irrigation, has che poten-
tial of relegating the pink bollworm to minor pest status. In fact,
growers who have practiced early termination have had few pink bollworm
problems in their cotton production.
To summarize, it should be emphasized that cultural concrol, like
biological control and other p«st management tactics, is a population
lowering procedure. This may require a re-aducation of the grower so that
he understands the concept of living with continuous pest populations
but at levels sufficiently low that economic damage is unlikely. It will
also require chat che growers and their pest management advisors chink
in terms of long-range concrol rather chan for convenience and short-term
profics only.
69
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REFERENCES
Adkisson, P.L. 1972. Use of cultural practices in insect past manage-
aent pp. 37-50. In: Implementing Practical Pest Management Strategies
Proc. Nat. Ext. Insect Pest Mgmt. Workshop. Purdue University,
Lafayette, Ind. March 14-16, 1972. 647 pp.
Adkisson, P.L. and J.C. Gaines. 1960. Pink bollworm control as related
to the total cotton insect program of Central Texas. Tex. Agric.
Exp. Sta. Misc. Publ. 444. 7 pp.
Anonymous. 1969. Insect-Pest Management and Control. Nat. Acad. Sci.
Pufal. 1965. 508 pp.
Bishop, G.W. , D.W. Davis and T.F. Watson. 1978. Cultural practices in
pest management. In Environmental Improvement through Biological
Control and Pest Management. Western Regional Bulletin (In press).
Gerhard t, P.O. and Leon Moore. 1962. Sorghum midge— a new pest in
Arizona. Prog. Agric. in Ariz. Vol. XIV (1):12-13.
Isely, Daight. 1946. Methods of Insect Control (Part I). Burgess
Publ. Co. 134- pp.
Komarek, E.7., Jr. 1969. Environmental Management. Proc. Tall Timbers
Conf. on Ecol. Anim. Contr. by Habitat Mgmt. 1:3-11
Met calf, C. L. , W.P. Flint and R.L. Metcalf. 1962. Destructive and
Useful Insects. McGraw-Hill, New York 1087 pp.'
Noble, L.W. 1969. Fifty years of reasearch on the pink bollworm in
the United States. USOA Agric. Handbook No. 357. 62 pp.
Rakickas, R.J. and T.F. Watson. 1974. Population trends of L'^gus
spp. and selected predators in strip-cut alfalfa. Environ. Entomol.
3:781-4.
Slosser, J.E. and T.F. Watson. 1972a. Influence of irrigation on
overwinter survival of the pink bollworm. S'/tvizvm. Entomol. 1(5):
S72-S78.
Slosser, J.E. and T.F. Watson. 1972b. Population growth of ch» pink
bollworm. Ariz. Agric. Exp. Sta. Tech. Bull. 195. 22 pp.
Stern, V.M. 1969. Xntarplanting alfalfa in cotton to control lygus
bugs and other insect pests. Proc. ^Ta.11 Timbers Conf. Ecol. Ania.
fcontol Habitat Mgmt. 1:55-69
Stern, V.M. , R. van den Bosch and T.F, Laigh. 1964. Strip-cutting
alfalfa for lygus bug control. Calif. Agyic. 18(41:4-8.
van den Bosch, R., C.F. Lagace and V.M. Stsrn, 1967. The iatarrelation-
ship of the' aphid, Acyrthcsipkan pisun, and its parasite, Ashidiua
smithi, in a stable environment. Ecology 43:993-1000.
van den Bosch, R. and V.M. Stern. 1969. The effect of harvesting prac-
.tices on the pink bollworm in Arizona. J. Econ. Entomol. 61(4): 1041-1044.
Watson, T.F. and W.E. Larson. 1968. Effects of winter cultural prac-
.tices on the pink boliwora in Arizona. «. Essn. internal. 61(4): 1041-44.
Watson, T.F., W.E. Larsen, K.3L Barnes and D.G. Fullerton. 1970.
Value of stalk shredders in pink bcllworm control « «/*. zscn. Entomol.
Watson, T.F., K.K. Barnes, J.E. Sloss«r and D.G. Full^rtan. 1974.
influence of plowdown dates and cultural practices on spring moth
uamergence of the pink bollworm. J. Eson. Entomol. 87(2) : 207-210.
Watson, T.F., Leon Moore, and G.W. Ware. 1976. Practical Insect Pest
Management. W.H. Frgeoan and Company. 196 pp.
Watson, T.F., F.M. Cara»so, D.I. Langs ssu, E.3. Jackson, and fi.G. Fullerton.
49 7_. Pink boliwora control in relation ce crop germination, v.
Eacn. internal. (In press}.
7Q
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AS HURD
Everitt R. Mitchell
Insect Attractants, Behavior and Basic Biology Research Laboratory
Federal Research, Science Education Administration
U.S. Department of Agriculture ;
Gainsville, Florida
Many researchers are investigating the use of sex attractant pheromones
for managing insect pest populations. Already these potent chemicals
are widaly used to monitor seasonal changes in populations and to fore-
cast potential problem areas, locate pest infestations previously un-
detectable by more conventional methods, and to schedule insecticide
applications. These materials also are being evaluated for direct con-
trol of several important pests by mass trapping or disruption of pre-
mating communication. This paper discusses some of the most promising
developments along these lines.
DISRUPTION OF MTING
Sex pheromones may provide control of insect pests by disrupting mating
and thereby reduce subsequent larval infestations. The mechanisms by
which disruption are accomplished are not well understood'; the term
atmospheric permeation, which implies no specific mechanism, has generally
been accepted as descriptive of this approach.
Field Crops
Several recent studies have demonstrated control of insect pests via
air permeation. Shorey at al. (1974) treated a 4.8 ha. cotton field with
hexalure-impregnated cotton string evaporators during the summer of 1972.
Hexalura is an attractant for male pink bollworms, Pea-c-inophova gossy-
piella (Saunders), but is not the sex pheromone. This test was repeated
in 1973 with different cypes of hexalure evaporators and evaporator spacings.
Inspection of immature cottoa bolls at the time of highest potential damage
(mid-August) indicated that numbers of pink bollworm larvae were reduced
83% to 93% compared with control fields. In another test, hexalure-
treated fields and fileds treated 4 to 8 times with carbaryl had approx.
the same level of larval infestation in cotton bolls.
i
This paper reports the results of research only. Mention of a commercial
or proprietary product or of a pesticide in this paper does not constitute
a recommendation for use by the U.S. Department of Agriculture nor does
it imply registration under FIFRA as ammended.
71
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Gossyplure, the true sex pheromone of the pink bollworm, was identified
in 1973 and proved to be a much more effective mating disruptant than
hexalure. Therefore, during the. 1974 growing season, gosayplure was
used to treat approximately 1600 ha of cotton in the Coachella Valley
of California (Shorey et al. 1976). A total of 9 g of gossyplure/ha
was distributed over the season, giving a release rate of 12/mg/24hr/ha.
Through mid-August, the larval infestation in bolls was comparable with
that observed during the 3 previous seasons in fields that received
conventional insecticide treatments. Also, there was a 3- to 4-week
delay in the onset of larval infestations in the bolls in 1974 as com?*
pared to previous years. However, conventional insecticides were re-
quired in some areas of the Valley to provide late-season control of the
pink bollworm. The investigators concluded that the 40 m separation
between glossyplure evaporators was probably marginally wide for pro-
viding effective control.
Gaston et al. (1977) treated 5-, 6-, and 12-ha cotton fields with gossy—
plure during the 1976 growing season. Fheronone was evaporated from
hollow, 104-mm long, thermoplastic fibers (ConrelR fashioned into
hoops of 1.5 revolutions). The hoops were attached to the cotton plants
by hand at 3-week intervals (from mid-May through early September)
on a 1 X 1 m grid throughout each field (five applications). The fields
treated with gosayplure and nearby control fields treated as needed with
conventional insecticides were then monitored weekly with gossyplure-
baited traps; also, larval infestations in bolls were monitored weekly
in each field. Monitor traps positioned in the fields treated with
gossyplure captured 98% fewer pink bollworm males than pheromone-baited
traps located in fields treated with insecticides. Moreover, there was
a substantial reduction in the number of pink bollworm larvae in cotton
bolls in the gossyplure-treated fields vs. the insecticide-treated fields.
Results showed an average 9-fold reduction in insecticide applications
per hectare in the pheromone-created fields compared with applications
in the fields treated solely with insecticides for pink bollworm control.
Large-scale field trials in which gossyplure was used as a mating dis-
ruptant for the pink bollworm also were conducted in cocton in Arizona
by Conrel, FRL-Albany International, Norwood, Mass., during the 1976
growing season. Their results showed gossyplure to be an affective
control for this pest when used in conjunction with conventional in-
secticides (Roger Kitterman, personal communication). Only approximately
157. of the fields in this test required any insecticide, and the number
of applications of insecticide in the fields that did require treatment
was reduced 50% to 60% from the number to protect the control field,
which was treated conventionally. Many growers in Arizona are consider-
ing a total pheromone-insecticide program in 1978.
Marks (1976) reduced the level of mating of Diparopsia ezatanea Heaps
(the "red bollworm" of cotton in Central and Southern Africa) by eva-
porating its sex pheromone (dicaotalure) in a 0.2 ha field cage.
Oicastalure at 21 and 42 g/ha produced average reductions in mating
of 47% and 72%, respectively, for one month. An inhibitor of sale sex
72
-------
attraction (E_)-9-dodecen-l-ol acetate, applied at the rate of 37 g/ha
reduced mating by 71%. He also showed that the degree of mating
disruption in these tests was density-independent for moth populations
of up to 2,200/ha.
The feasibility of using the air permeation technique for mating control
of the corn earworm, Beliotkia sea (Boddie), and fall armyworm, Spodaptera
frugiperda (J.E. Smith), was demonstrated by Mitchell et al. (1974,
1975, 1976) with (Z)-9-tetradecen-l-ol formate (Z-9-TDF) or (£)-!!-
hexadecenal (Z-11-HDAL) used for the corn earworm and (Z,E_)-9,12-tetradecadien-
l-ol acetate (ZETA) used for the fall armyworm. Z-9-TDF is a chemical
of non-biological origin; Z-11-HDAL has been reported as a component
of the corn earworm sex pherooone (Roelofs et al. 1974); and ZETA is a
part of the sex pheromone of several Spodopteva. spp., though it is not a
pheromone of the fall armyworm (Mitchell and Doolittle 1976). In these
tests, mating by corn earworm females was suppressed 852 in plots treated
with Z-11-HDAL and 962 in plots treated with Z-9-TDF. In plots treated
with ZETA, mating by fall armyworm females was reduced 88%.
The majority of the experiments conduct'ed to date with semiochemicals
used for pest control have concentrated on single key pests. However,
it is manifest that modern pest management strategies be devised to
attack the problems created by complexes of pests, often in complexes
of crops. Where it is feasible, manipulation of the behavior of sevexal
coexistent insects musc_be incorporated into an overall strategy. The
opportunity exists to demonstrate such management capability with behavior-
modifying chemicals chat can be formulated to provide a multi-chemical
attack on mating behavior.
Mitchell (1975) and Mitchell et al. (1976, 1977) proposed and demonstrated
the feasibility of usjjrg multi-chemical formulations to disrupt mating
among coexisting pest insects, the corn earworm and fall armyworm. When
Z-9-TDF and ZETA were evaporated in separate plots, matings by the corn
earworm and fall armyworm were reduced 96 and 88% respectively. When
Z-9-TDF and ZETA were evaporated simultaneously in the same plot, matings
by corn earworm and fall armyworm females were reduced 37 and 92%,
respectively; a clear indication of the compatability of these two chemicals.
On the basis of these encouraging results, a 4-year research program will
be initiated in 1978 to develop the technology for suppressing populations
of the corn earworm and fall armyworm in sweet corn. The use of mating
disruptants against these pests should permit a significant reduction
in the number of insecticide applications (18-24) now required for control
of pest insects in this crop. Moreover, the knowledge gained from these
tests should be widely applicable to a broad spectrum of insect pests
of field and vegetable crops in areas where it may be desirable to use
air permeation alone or in other areas where integrated pest management
programs involve conventional pesticides, biocontrol agents, and good
cultural practices.
Fruit Crops
Air permeation also is being investigated as a possible control method
73
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for several important insect pests of fruit crops. The "summer
fruit tortrix", Adosaphyea orona F.V.R., is the chief insect pest in
Dutch apple orchards. The pharomone of this species has been identified
as a,mixture of 2 positional isomers, CZ)~9- and (Z)-ll-tetradecen-l-ol
acetate (Meijer et al. 1973). The geometrical isomers (£)-9- and
(E)-ll-t«tradecen
-------
Forest Pescs
The air permeation technique is also receiving serious consideration as a
method of regulating some important forest pests. The Canadian Forest
Service is exploring the possibility of distributing fuluro (a 97:3
blend of (E)~ aad (Z,)-ll-tetradecen-l-ol), to suppress population growth
of the eastern spruce budworm, Choristoneura flaniferana (Clemens)
(Sanders, personal communication). In addition, 6.E. Daterman and co-
workers (personal communication) have obtained good efficacy data on dis-
ruption of pheromone communication in the Douglas-fir tussock moth,
Semeroaampa pseudotsugata HcDunnough, on small (1 ha) plots by using point-
source releases. They plan to move toward evaluation of an "operational"
control-release system in the near future; and they also plan to evaluate
mating disruption as a possible control system for the "western pine shoot
borer", Eucoaoma aonomona. Kearsott. -
PHERCMCNE TRAPS
The possibility of using pheromonos as a survey tool has received wide
attention. By relating daily changes in the number and distribution of
Spodoptera Httoralis Boisduval males captures in a network of pheromone
traps scattered throughout Cyprus with the prevailing meteorological
conditions, Campion et al. (1977) was able to show that this species was
endemic to the island. Thus, there was no evidence to support the hypo-
thesis that 5. littoralia migrates to the island each year from neighbor-
ing countries on the mainland.
Spodoptera exempts. (Walkar) is an important pest of pastures and related
field crops such as corn in East Africa. This species is highly migratory
in habit, and changes in its distribution can be related to synoptic
weather (Brown et al. 1969). The establishment of a network of light
traps throughout the region has made it possible to develop and early
warning system co alert farmers of incipient anayworm outbreaks.
The recent indentification of the pheromone of S. exermto. (Beevor et al.
1975) allows a more comprehensive trapping system, particularly in the
more remote parts of East Africa where electric power is unavailable.
Field trials with pheromone trapa indicate a close correlation between
light and pharomone trap catches, so the two trapping systems can supplement
each other. This is particularly important at periods of full moon when
light crap catches are dapresosd, but moth captures in pheromone traps are
unlikely co ba affactad.
For several species, pharomone traps have proved to be a reliable dovice
for aarly detection of Che adult population and for indication of possible
infestation by larvae. Minks and deJong (1975) devised a method for
scheduling sprays to control A. orona in Dutch apple orchards based on
pheromone crap catches and temperature recordings. Prediction of agg
hatch is baaed on observations during embryonic development of the eggs.
A model has been developed for quick calculation of the stage.of egg
development as a percentage of total development. As soon as.the cumulative
75
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percentages exceed 100, hatching can be expected, and advice to farmers
to "spray now" can be issued.
The pheronone trap has greatly facilitated study of the population dyna-
mics and control of the codling moth. Corft (1975) and Riedl et al.
(1976) have developed an extensive model system that utilizes pheromone
trap catch data taken in early season as reference points and couples
thea with a physiological time model that forecasts critical events
(egg hatch, emergence, damage, etc.) for spray timing. Inputs needed
to use the model are first trap catch and peak catch from the spring
moth generation. When coupled with online weather inputs, this system
provides output options including predictive statements of developments,
maps of development, and forecasts of life stage changes for the two
generations of moths occurring in 27 sites across the Michigan fruit
belt.
Limiting crop injury by trapping insects with pheromones has generally
been unsatisfactory, especially in situations involving moderate to
high-populations where only one sex of the species is affected. However,
aggregation pheromones that attract both males and females to a common
site appear to be more amenable to this approach.
The "ambrosia beetle", Gnathotrichua auloatus (LeConte), is a pest of
freshly sawn, unseasoned lumber in sawmills in the Pacific Northwest.
The presence of these beetles in export lumber from the west coast of
North America (Milligan 1970) has led to quarantine problems with import-
ing countries that have extensive exotic forests. Also, because of the
ability of the ambrosia beetle to complete its life cycle within sawn
lumber (McLean and Borden 1975), there is a need for protecting freshly
sawn lumber from this insect (McLean and Borden, in press).
The population aggregation pheromone for the ambrosia beetle, sulcatol
(6-methy-5-hepten-2-01), was isolated, synthesized, and successfully
field tested by Byrne et al. (1974). McLean and Borden (in press) de-
veloped a mass-trapping technique with sulcatol to suppress populations
of ambrosia beetle in newly sawn lumber. Briefly, sulcatol-baited traps
are strategically placed next to piles of attractive fresh slabbing chat
could be colonized by beetles not captured in the traps. At the end of
attractive period, approx. four weeks, the slabs are removed and chipped,
thus killing any beetles that attacked them. This system was success-
fully field-tested In a commercial sawmill on Vancouver Island, B.C.,
during 1975 (McLean and Borden, in press), and 1976 (J.A. McLean, personal
communication). Although the system has not provided 100% control of the
problem, industry has been sufficiently impressed with the results to
continue the trap-out program on their own as a part of their quality con-
trol procedure (J.H. Borden, personal communication).
3
FORMULATION
Before insect aox attractant pheromonas or ocher semiochemicals can be
used affectively, they oust be incorporated into a system chat will give
i
76
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a constant, dependable level of chemical release and protect them from
the degradative action of the weather. Dispensers of many types,
including cotton dental wicks, plastic vials and caps, poly/vinyl chloride
rods, rubber bands, and rubber stoppers have long been used to dispense
pheromones from traps. The recent development of the laminated plastic
strip (HerconR) and the hollow fiber (Conrel&) dispenser systems has
greatly facilitiated research in the use of pheromones. Both of these
systems are used by researchers and commercial concerns to dispense
pheromones from traps, because they can be engineered to give the desired
release rate and longevity under almost any kind of environmental condi-
tion.
The technology for formulating pheromones for use in air permeation trials
is much less advanced than it is for trapping situations. Many different
commercial formulations including microcapsules (NCRR and Fenwalt^),
laminated plastic strips (Hercon), and hollow fibers (Conrel) have been
tested in the United States and foreign countries during the past several
years with varying degrees of success.
Gaston et a. (1977) and Roger Kitteraan were able to demonstrate economic
control of the pink bollworm in irrigated cotton in desert areas of
California and Arizona, respectively, by permeating the air with gossy- '~
plure formulated in Conrel fibers. In California, the fibers were fashioned
into hoops and applied by hand to ensure that they remained on the plan:
throughout the growing season. In Arizona, chopped fibers were appliet
with a machine specifically designed to stick the fibers onto the foliage.
StMftHJT
Scientists working with insect sex pheromones are generally optimistic
about their role in pest management schemes. Their most significant use
probably will be in the areas of population sampling and monitoring
and in the development of techniques for predicting population trends
and infestation levels. Application of pheromones and antipheromones
for mating control also show considerable promise in many cropping
systems. Such studies eventually will lead to improvement in insect
pest management with a concomitant reduction in environmental pollution.
REFERENCES
Beevor, P.S., D.R. Hall, R. Laster, R.G. Poppi, J.S. Read, and B.F. Nesbitt.
1975. Sex pheromones of the armyworm Spodopterz exempts. (Walk.)
Es^enentia. 31:22.
Brown, E.S., E. Betts, and R.C. Rainey. 1969. Seasonal changes in distri-
bution of the African armyworm, Spodoptsrz exempta (Walk.) (Lep.
Moctuidae) with special reference to Eastern Africa. Bull. En-camol.
Res. 58:861-728.
77
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Byrne, K.J., A.A. Swigar, R.M. Silverstein, J.H. Borden, and E.
Stokkink. 1974. Sulcacol: Population aggregation pheromone in the
scolytid b«otle, Gnathotriahus aulcatua. J. Insect Phyaiol.
20:1895-1900.
Campion, D.6., B.W. Bettaay, J.B. McGinnigle, and L.R. Taylor. 1977.
The distribution and migration of Spodoptera li.ttQV
-------
Mitchell, E.R., M. Jacobsen, and A.H. Baumhover. 1975. Heliothia
spp.: Disruption of pheromonal communication with (20-9-
tetradecen-1-ol formate. Environ. Entomol. 4:577-79.
Moffitt, H.R. 1975. Alternate methods for control of the codling
moth. _In Proceedings, U.S.-U.S.S.R. Symposium: The Integrated
Control of the Arthropod, Disease, and Weed Pests of Cotton,
Grain Sorghum, and Deciduous Fruit. Sept. 28-Oct. 1 , 1975,
Luccock, Texas.
Ricdl, H., B.A. Croft, and A.J. Hovitt. 1976. Forecasting codling
moth phenology based on pheromone trap catches and physiological-
time models. Can. Entomol. 108(5):449-60.
Roelofs, W.L., Ada S. Hill, R.T. Garde, and Thomas C. Baker. 1974.
Two sex pheromone components of the tobacco budworm moth,
Eeliothia vireacens. Lifa Sciences 14:1555-62.
Shorey, H.H., L.K. Gascon, and R.S. Kaae. 1976. Air-permeation with
gossyplure for control of the pink bollworm. _In Pest Management
With Insect Sex Attractants, Morton Beroza (ed.). Ann. Chen.
Soc. Symposium Series 23. 192 pp.
Shorey, H.H., R.S. Kaae, and L.K. Gascon. 1974. Sex pheromones of
Lepidoptera. Development of a pheromonal control of Peatinophora
goaaypiella in cotton. J. Econ. Entomol. 67:347-50.
Sower, L.L., and G.P.Whinner. 1977. Population growth and mating
success of Indian meal moths and almond moths in che presence of
synthetic sex pheromone. Environ. Entomol. 6(l):l7-20.
79
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80
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BREEDING INSECT RESISTANCE IN PLANTS:
A CASE STUDY OF WHEAT AND HESSIAN FLY
• R.L. Gallon
Department of Entomology
Purdue University
West Lafayette, Indiana
EARLY CCNIRDL TACTICS
Breeding resistance to insects in crop plants has made tremendous strides
during the past 20 years. "The late Dr. Painter and his co-workers
showed that insect resistance as well as disease resistance are important
components of yield when bred into a crop. Today almost all food and
fiber crops have a number of major insect pests attacking them, and breed-
ing for resistance to these insects in crop plants is an integral part
of pest management. Indeed, the use of resistant varieties is often
the sole method of control. In the case of the Hessian fly, Mayetiola.
destructor (Say), on wheat, the planting of resistant varieties is the
main control method used although resistant varieties are sometimes in-
tegrated with cultural, chemical, biological and genetic control programs.
The Hessian fly is believed to have immigrated to the U.S. in the wheat
straw bed rolls of Hessian soldiers in 1777, hence its name (Havens 1792).
Since its introduction this insect has spread throughout the wheat grow-
ing area of the United States (Gallun 1964). The adults are mosquito-
like in size but their presence in an area can lead to serious losses in
wheat. The female oviposits on the leaves of newly planted fall winter
wheat in the Midwest and the Great Plains, and the larvae (1/2 mm in size)
that hatch from the eggs migrate down the leaf, between the leaf sheaths,
to the base of the plant where they begin to feed on the cell sap. During
the first four days of feeding the larvae secrete A substance into the
plant or take something out that results in the stunting and eventual
death of the plant. The larvae continue to feed and grow until they reach
a length of approximately 3 mm., then their skins turn a dark color and
resemble flax seeds. This "flax seed stage" is the overwintering stage
of the Hessian fly in the Midwest and Great Plains states where temperatures
remain below 38°TT for long periods.
The larva* pupate in the spring and emerge as adults to reinfest the
wheat planted the previous fall. Eggs are again laid by the females but
this time higher up on the plant since the plant is now in the jointing
stage. Tha larvae migrate down the leaf to the node and feed. There
they complete their lift cycle by oversummering on the wheat stubble and
81
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emerge again in the fall as adults. Thus damage by the second brood of
Haitian fly consists of weakening the stem at the sites where the larvae
feed.( This results in lodging and breaking of straw. Also the sizes of
the wheat heads are reduced as are kernal size and weight.
Because of the damage this insect caused in many of the wheat growing
states, the U.S. Department of Agriculture and state agricultural ex-
periment stations started studies on its life history and on ways to
control it. Different control measures emerged: cultural practices
such as proper tillage to turn under the stubble; reduction in volunteer
wheat upon which the flies could survive; natural parasitism; safe
seeding dates; insecticides; and finally resistant varieties. *
^
It is known that biolobical control by native parasites will help to
reduce Hessian fly populations, but as far as I know a parasite re-
lease program has not been initiated. Chemical control with systemic
insecticides, both in granular form and seed treatments (Brown 1957),
has been worked out and has been effective, but the cost of treating
seed, problems of toxicity, and eventual loss of effectiveness has
prevented its use.
Safe seeding dates can control Hessian fly populations fairly well.
From research it was discovered that wheat could be planted in the fall
after most of the Hessian flies emerged from wheat stubble; hence the
wheat would escape damage (Davis 1918, Larrioer and Packard 1929).
Most of the time this worked, but it did not prevent damage from flies
that infested volunteer wheat in the spring. Also there were times when
a cool fall kept the flies from emerging until after che fly-free dates.
However, safe seeding dates were used quite extensively.
The first resistant wheat variety was developed in the late 1700's
(Havens 1792, Fitch 1847). In New York a oilier named Underbill planted
some of his milling wheat; it proved to be resistant to Hessian fly
and demand for his wheat increased. "Underbill" wheat became the popular
wheat' grown in New York at that time.
It was not until the early 1900's that breeding.for resistance co
Hessian fly in wheat became an integral part of wheat breeding programs
throughout the country. State experiment stations in California, Kansas,
Nebraska, and Indiana in cooperation with the U.S. Department of Agri-
culcure, were the forerunners in developing resistant varieties. To
date 49 Hessian fly resistant wheat varieties have been developed and
released to wheat growers by 11 state experiment stations and two commercial
seed companies in cooperation with the U.S. Department of Agriculture.
Hessian fly larvae that feed on susceptible plants cause che stunting
of the plant which takes on a dark green color. Larvae chat begin to
feed on resistant wheat die within a few days, and the plant continues to
grow. We still do not know what causes this resistance. It may be a
toxin, a nutritional deficiency, or even a non-preferred compound or
character that the larvae do not like. In any case, the resistance is
82
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genetically controlled and can be transferred to susceptible wheat by
plant breeding. Moreover, in wheat we are blessed with many different
genes for resistance to Hessian fly and these genes are still being
utilized in modern breeding programs. (See Table 1).
MODERN BREEDING PROGRAMS
The breeding of resistant wheats is a team effort that utilizes the skill
of different professionals, however, the entomologists and pmthologists
have similar roles. The entomologist works with resistance to insects
whereas the pathologist works with resistance to pathogens. Both work
with the geneticist-plant breeder to determine the genetics of resistance
and the nature of resistance (Cartwright and Wiebe 1936; Fainter et *1.
1940; Caldwell et al. 1947; Shandn and Cartwright 1953;Allan et al. 1959;
Patterson and Gallon 1974).
Laboratory populations of eight biotypes of the Hessian fly are reared
in the greenhouse and used for evaluating wheats. We work with seedling
resistance although resistance also functions in mature plants. We
evaluate wheats, 20 entries to a greenhouse flat, plus checks. Depend-
ing on the type of crosa made and the generation of the plant populations
being evaluated, we score the rows by number of resistant and susceptible
plants. This information, and resistant plants, are returned to the
breeder for further crosses or selection purposes. During the year we
evaluate from 6 to 10 thousand entries for resistance to at least 2
biotypes of fly, sometimes 4. Our Lafayette laboratory cooperates with
approximately 5-6 states and three commercial companies. Our Manhattan,
Kansas, laboratory has a similar program with wheat breeders in the Great
Plains states.
When resistance in a plant has an adverse effect on the life cycle of
an insect, then insect biotypes (or races) are likely to develop (Gallun
and Reitz 1971). Because resistance in wheat kills the Hessian fly,
there is extreme selection pressure in Hessian fly populations for in-
sects chat can survive upon the heretofore resistant plant, and these
individuals are called biotypes. The biotype situation is analagous
to the loss of insecticide control when insects build up resistance to a
chemical. When Hessian flies attack wheat having single dominant genes
for resistance, there is selection for biotypes having specific genes for
virulence or the capability of overcoming resistance. These biotypes
are determined by the reaction of wheats having different genes for
resistance to the progeny of a single pair mating. :
In our work we are using wheats having 4 different genes for resistance
as differentials. By doing so we have set up a situation in which 16
biotypes could occur. Of the 16 possible biotypes, we already have nine
and are working on more. Table 1 shows the genes for resistance that
have been discovered and the plant reactions to biotypes we have isolated
or bred.
83
-------
Can«
HA
B3
H3
*»
87*8
BT
Oriatn
• *fftg
-------
average state infestations of certified wheat fields to be less than 2
percent in each state - a tribute to the growing of resistance varieties.
In other words we try to keep ahead by studying the genetic interrelation-
ships that exist between plant and insect by locating new sources of resis-
tance and breeding new biotypes of fly.
The laboratory-bred biotypes are used to seek new sources of resistance
to overcome any new biotype formation that appears in the field. They
can also be used to distinguish between genes for resistance and to deter -
mine whether different genes are combined. Our studies of Hessian fly
biotypes have led to a new and exciting method of genetic control. First
we have found that the Great Plains biotype has dominant genes for
avirulence at every loci comparable to loci carrying genes for resistance
in different wheats. We then developed a model that could suppress popu-
lations of Hessian fly populations of biotypes in the Eastern United
States by the release of the Great Plains fly in the field (Hatchett and
Gallon 1967; Gallun and Hatchett 1969). Matings between Great Plains
fly and native flies result in progenies that cannot survive on Eastern
wheats having genes for resistance. Also progenies of G? x GP matings
cannot survive. Only progenies of native x native can survive. By
releasing large numbers of GP relative to native fly, suppression to almost
eradication can be achieved by a few generations of releases.
When different release ratios of G? to native fly were programmed, the
20 GP:1 native releases almost eradicated the native fly in 3 generation
of release in the greenhouse and in the field; the control population
remained almost constant and even increased (Foster 1977). This is one
more example of integration of resistant varieties with another control
method.
Progress in controlling the Hessian fly has resulted from cooperative pro-
grams of breeding for resistance to Hessian fly. Figure 1 shows the
results of releasing resistant varieties in Kansas. When there were high
acreages of resistant varieties, Hessian fly infestations decreased
(determined by number of puparia per 100 culms). However, when this
acreage decreased, infestations increased. Figure 2 shows a similar situa-
tion in Indiana. Before the release of resistant varieties, field in-
festations were high. After the release, infestations dropped and re-
mained low.
Table 2 shows the percent of wheat acreages planted co resistant varieties
in 1974 in 42 states. During 1974, 14 varieties of resistant wheat were
grown on more chan 11 million acres in 15 states in the hard red winter
uhttat region. During the same year 23 varieties of resistant wheat were
grown on more than 8 million acres in at least 26 states in the soft
whaac region. In the entire wheat region in 1974, 37 varieties of wheats
ray is cant to the Hessian fly were grown in 35 states on more than 20
million acres, or approximately 39 percent of the total wheat acreage
grown in the U.S. (Gallun and Briggle from 1974 national wheat survey
unpublished).
85
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80"
60'
u 40-
ac
w
20-
2 Wheat Acreage Planted
To Resistant Varieties
Hessian Fly Infestation Puparia'
A Per 100 Culms / J
^yv ---"'
1949 1952 1955 1958 1961 1964 1967 1970 1973
, Figure 1 Graph represents a 17 county area of North Central
Kansas infestation based on susceptible varieties.
Percentages of wheat acreage planted to Hessian fly
resistant wheat varieties compared with maximum
Hessian fly infestations 1949 through 1973.
(from Somsen and Oppenlander, 1975)
% Acreage
Resistant
Cultivars
19*0
19»J
1970
1973
TEAR
Figure 2
Percentage of wheat acreage planted to Hessian fly
resistant wheat varieties in Indiana compared with
average Hessian fly infestations years 1919-1977.
86
-------
State
AL
AZ
AX
a
CO
ox
re
SA
to
XL
a
u
33
sr
u
XD
MI
MB
>S
MO
ffl
SB
S7
V
3M
XT
K
TO
CH
or
OR
?A
SC
SO
or
TX
OT
VA
VA
wv
Wl
WY
Bard
Bo. Of red
TtrittiM vtattr
11
0
13
0
5
j
3
b
0
17
U
12
U
3
k
5
10
0
u
13
3
U
0
3
3
2
8
1
9
0
9
7
li
U
3
1
a
0
8
9
- 5
0.0
0.0
0.0
0.0
5b.2
0.0
0.0
0.0
0.0
15.0
.1
57.9
U7.5
0.0
0.0
0.0
0.0
0.0
0.0
9.9
3.3
52.6
0.0
0.0
37.3
0.0
0.0
0.1
0.0
20.0
0.0
0.0
0.0
10.7
0.9
3.5
1.3
0.0
0.0
0.2
1.6
28.8
Eard
red
rprla«
0.6
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
2.1*
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
• 0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.5
0.0
Soft
rtd
viater
(Percent)
Ut.6
0.0
90.5
0.0
0,0
81.2
85.7
' 51.1
0.0
7«».8
98.U
0.0
0.1
83.1
51.8
78.7
23.1*
0.0
52.9
o!o
0.0
0.0
69.6
0.0
O.b
75.9
0.0
95.6
0.0
0.0
71*. 8
31.2
0.0
85.6
1.U
0.0
77.6
0.0
66.0
2.8
0.0
Soft
red
«?rlaf
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
White
vioter
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
27.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.6
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.6
0.0
0.0
Total
U.6
0.0
50.5
0.0
5I». 2
81.2
85.7
51.1
0.0
89.3
98.5
60.3
U7.6
83.1
51.3
78.7
50.7
0.0
52.9
SU.o
3.8
52.6
0.0
69.6
37.3
1.0
75.9
0.1
95.6
20.0
0.0
7^.3
31.2
10.7
56.;
9.9
1.3
77.6
0.0
66.2
5.9
29. a
RO. states is.
vbieh
jrovn 13
2
25
0
3
35
Table 2 Percent of State wheat acreages grown to Hessian fly
resistant wheats in 1974,
37
-------
Yield studies have shown that wheat growers save at the least one bushel
per acre of wheat by growing resistant varieties. If wheat sells in the
range of $2 to $3.50 per bushel, we have saved approximately $40-70 million
in one year; a pretty good return on the investment in agricultural research.
So this is the status of Hessian fly resistant varieties today. We have
many resistant varieties that are being grown in the U.S., and they are
doing the job they are supposed to be doing; protecting the crop. We
must always keep on top of things and search for new sources of resistance
and monitor for new biotypes. Team work is essential in the breeding pro-
gram. Integrated control methods such as safe seeding dates, good cul-
tural practices, the release of parasites, and genetic control can and
should-be used in connection with resistant varieties. Many researchers
and farmers havo made this program a success.
KErfiKENCES
i
Allan, R.E., E.G. Heyne, E.T. Jones, and C.O. Johnston. 1959. Genetic
analysis of ten sources of Hessian fly resistance, their interrela-
tionships and association with leaf rush reaction in wheat. Kansas
Agric, Sxs. Stn. Tech. Bull. 104, SI pp.
Brown, H.E. 1957. Hessian fly control with systematic insecticides.
F.A.O. Plant Protect. Vol S(ZO):149-ISS.
Caldwell, R.W., W.B. Cartwright, and L.E. Coopton. 1946. Inheritance of
resistance derived from W38 and durum PI 94587. J. Am. Soa. Agron.
38(5):398-409.
Cartwright, W.B. and G.A. Wiebe. 1936. Inheritance of resistance to
the Hessian fly in wheat crosses Dawson x Poso and Dawson x Big
Club. J. Agrie. flea. 52:691-695.
Davis, J.J. 1918. The control of three important wheat pests in Indiana.
Indiana Agric. Sxp. Stn. Circ. 82:1-11.
Foster, J.E. 1977. Suppression of a field population of the Hessian
fly by release of the dominant avirulent Great Plains biotype. J.
Soon. Entamol. 70:775-778.
Gallun, R.L. 1964. The Hessian Fly. Sev. O.S.D.A. Farmers Bull. 1627:
1-9.
Gallun, R.L. and J.H. Hatchett. 1969. Genetic evidence of chromosome
elimination in the Hessian fly. Arm. Entente 1. Soa. Am. 32(5):1095-1101.
Gallon-, R.L. and L.P. Reitz. 1971. Wheat cultivars resistant to races
of Hessian fly. U.S. Dept. of Agric. ARS Prod. Res. Rep. 134:1-16.
Hatchett, J.H. and R.L. Gallun. 1967. Genetic control of che Hessian
fly. Proc. N.C. Branch Entomol. Soc. Am. 22:100 (abstract).
Havens, J.N. 1792. Observations on the Hessian fly. Soc. Agron. New
York Trans. Part I: 89-107.
Larrimer, W.H. and C.M. Packard. 1929. Hessian fly control in Indiana.
Indiana. Agric. Esp. Stn. Giro. IS?:1-12.
Painter, R.H., E.T. Jones, C.O. Johnston and J.H. Parker. 1940. Trans-
ference of Hessian fly resistance and other characteristics of
Marquillo spring wheat to winter wheat. Kens. Agria. £sp. Stn.
Taoh. Bull. 49:1-65.
38
-------
Patterson, F.L. and R.L. Gallun. 1974. Inheritance of resistance of
Seneca wheat to Race E. of Hessian fly. Proc. 4th Int. Wheat
Genetics Syrup. Mo. Agric. Exp. Stn. (August 1973): 445-449.
Shands, R.G. and W.B. Cartwright. 1953. A fifth gene conditioning Hessian
fly response in common wheat. J. Am. Soo. Agron. 45(7):302-307.
Somsen, H.W. and K.L. Oppenlander. 1975. Hessian fly biotype distri-
bution, resistant wheat varieties and control practices in hard
red winter wheat. USDA. ARS-NC-34 (December) 7 pp.
89
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90
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THE ROLE OF CHEMICALS IN INTEGRATED PEST MANAGEMENT
B.C. Tweedy
CIBA-GEIGY Corporation
Greensburo, North Carolina
INTRODUCTION
It is a real pleasure for me to meet with you and discuss integrated
pest management. I have had the opportunity to work for a university,
the USDA and now with industry. I have also had the opportunity to visit
several countires, including the USSR, where both quality and quantity
of food is a great problem. Mr. de Jong has requested that I speak about
the role of agricultural chemicals in pest management programs.
I would like to begin by defining what I mean by integrated pest manage-
ment. I think of IPM as "the use of multiple control measures which are
compatible, economical, environmentally sound and culturally feasible
for managing pest populations at an acceptable level." In some countries
this "acceptable level" is somewhat different than in the U.S.; total
production is emphasized with less emphasis on quality of commodity pro-
duced. In the U.S. we want both high production and high quality. In
che Soviet Union the use of pesticides in pest management practices is
increasing. Ours is beginning to level off or decrease. I would like to
point out at this time that IPM is a U.S. term and most other countries
use IPC or Integrated Pest Control.
To many people, IPM means the use of only biological control measures.
To others, IPM implies the use of non-chemical control measures. However,
to most of the scientists and growers with whom I have been associated,
IPM means the use of several measures for controlling pests with a minimum
impact upon the environment. The correct use of chemicals is certainly
one of these control measures. This was brought out in the workshops
yesterday and today. Included in the definition of the word "correct"
is the choice of the right chemical, applied at the right rate and at
the right time. When chemicals are used in this manner, I believe we
have nothing to be ashamed of. However, we should be concerned when we
misuse chemicals. I believe the misuse of chemicals has le'd to most of our
current pestcide problems of public interest. By misuse, I am referring
to having inadequate knowledge available for defining the correct use.
I am not referring to illegal use because of use outside of' the label.
Today we read so much about the adverse effects of chemicals Co our en-
vironment, but little is said about the benefits of agricultural chemicals.
91
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These "benefits are very impressive and .1 wish I had time to discuss them
in detail. Dr. Pimentel made this point quite clear yesterday. The use
of agricultural chemicals has been, and is, a major factor in the U.S.
being the leading producer of high quality food and fiber with a minimum
number of people on the farm. The American farmer produces food for
himself and over 70 other people. The "other people" are freed from the
farm to work in other industries, or to become doctors, teachers, scientists,
or whatever they choose. No other country in the world enjoys the high
quality of food at the low cost, or low percent of total salary, as we
do in the U.S.
Secretary Bergland was quoted in a written version of his talk to the
National Agricultural Chemicals Association (NACA) on September 27, 1977
as stating that "there appears to be an opportunity to help ease this
nation's unemployment by using 'people power' instead of only chemicals
in our fight against pests." In Case Report 68 it was stated that con-
trolling weeds in corn by hand labor at the average farm labor price of
$2.65 per hour in 1976 resulted in a net loss of $66 per acre. The net
profit due to use of a herbicide was $78. In 1977 the price of corn went
down and the cost of labor went up, thereby making an even greater differ-
ential. In addition, there aren't enough unemployed people to control
weeds in U.S. crops even if they wanted to hoe weeds on the farm. I feel
it is a gross oversimplification to say that the way to solve unemployment
is to put the people back on the farm with hoes and fly swatters to con-
trol pests.
Another implication was made by Bergland that "in these energy-short
times" we are being unrealistic by using petroleum-based products to
manufacture pesticides. Information available from the U.S. Department
of Agriculture indicates that the increase in productivity from the use
of pesticides exceeds the total of agricultural exports. Also, this
same source indicates that there is a 70-fold return in energy used for
the petroleum-based pesticides.
COST/BENEFITS OF CHEMICALS
I believe the benefits of agricultural chemicals have outweighed and
continue to outweigh the costs. I do not deny that there have been costs.
One must also remember that costs are -apparent with other signs of "progress"
such as new highways, the emissions from cars and airplanes, suburban de-
velopments and many other insults which we have placed on our environment.
The key to the use of agricultural chemicals is to use them so they have
the maximum beneficial effect and the least negative effect on our
environment. Using them in sound pest management programs certainly
has merit and is being more actively researched now than in past years.
Emphasis by industry, universities and government research groups- is
being placed upon the more correct use of pesticides. As an industry,
we now know much more about what happens to our pesticides when they are
applied to the environment before we apply for registration. For example,
92
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we know how rapidly and how far chemicals leach in different soils,
how rapidly they break down in the environment, how toxic or safe
they are to fish, wildlife, mammals, and many other non-target organisms.
We are in a much better position than ever to define how to use chemicals
judiciously. We know that by using smaller amounts of two or three
chemicals applied in combination, we can frequently get better pest
control. While the total chemical applied per acre may frequently be
more, the effect on non-target organisms and the levels of residues is
usually much less. Some of the above research problems were at one time
considered basic research done only by a university.
Where are the real problems with chemical control? In the past, chemical
control in many instances has been used to attempt total elimination
of the pest from a crop. Nature has provided built-in systems to by-pass
such road blocks, so it should not be surprising to us that pests have
adapted to these measures in various ways and to varying degrees. Pest
resistance, however, is nothing new with the advent of organic chemicals.
Nature has provided us with pests which attack previously resistant
varieties of crops for many, many years. An example is the breeding for
resistance of wheat to wheat rust. Puooina Granri,nis, the causal organism
of wheat rust, has for several decades been outdoing the plant breeder
and a resistant wheat variety has remained resistant for only three to
four years.
Today we recognize that total control or absolute elimination of pests
is not essential. Today scientists and farmers recognize that the real
goal is to keep the pest population below an "economic threshold". We
recognize we can put up with some level of the pest, but we must control
it to a degree that it does not destroy our crops, or ruin the crop to
the point that it is uneconomical to the grower. Yes, growers as well
as the chemical industry must make a profit in order to survive. Thus,
the correct use of fertilizers, agricultural chemicals, selection of
crop varieties, biological control, crop rotations and other cultural
methods, breeding programs, irrigation practices, etc., all fit into this
program. No one factor, including chemicals, can do it all. It must be
a program using all the tools and resources available.
Controlling pests is a challenging exercise in applied ecology. In
order to achieve our goal of economical crop production and sound en-
vironmental practices, we must first have a good understanding of the
agroecosystem in which the crop is grown. This is essential to de-
h'ining a successful pest management program. We must know which pests
occur every year and cause an unacceptable amount of crop injury and
which pests are secondary because they generally do not cause significant
yield losses. Pesticides play a key role in controlling each of these
types of pests and I believe we are in a better position now than ever
before to more correctly define the use of pesticides in most of these
pest control programs without causing any adverse effects. With a better
understanding of the various agroecosystems, we are approaching a new
horizon for agricultural chemicals in pest management systems. We now
have a better understanding of what types of compounds are desirable, and
93
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needed, in integrated pest management programs. The unfortunate thins
that has occurred is that the cost of developing agricultural chemicals
is so great that industry can no longer afford to develop them for some
of these special uses.
INMSTRY VIEW ON EM
How does the chemical industry see integrated pest management programs?'
Here again we must refer to the definition of IPM. Pest management
research programs , supported for many years by federal and st*e. f ,«^«
were accelerated in the early 1970 's. Their Jim was to deduce the "p^ti-
cide load in the agroecosystem. Although the programs were called pest
management programs, they were essentially insect management programs de-
signed, to scout crops such as cotton and apples in order to make better
decisions on when insecticides should be applied. Where properly carried
out, they have been quite successful in both pest control and the economics
of crotf production. As you saw from Dr. Frisbie's talk this morning
better cotton varieties have been integrated into the system and the'
cotton "pest management program has also been improved.
The National Agricultural Chemicals Association (NACA) , whose membership
is composed of companies that synthesize and manufacture most of the azri-
cultural chemicals used for pest control in the United States, has had a
keen interest in the pest management program development In 1972 the
following policy was adopted by the NACA' membership:
NACA endorses and urges support of programs which have
as their ultimate objective the achievement of pest
suppression based on sound ecological principles which
integrate chemicals, biological and cultural methods
into a practical program, where necessary and when possible.
4
One of the main objections the agricultural chemical industry has toward
the pest management programs that were developing was, industry was not
invited to participate in the planning of such programs or allowed to
give inputs where our proprietary compounds were concerned. We felt no
one knew more about the performance and safety of the chemicals used in
pest control than the companies that developed them. We could have made
and can; now make, very valuable inputs into such programs. However the'
chemical industry is looked upon as an avid opponent of pest management
because., the companies would "lose revenue." This is far" from reality
because most pest management programs do include the use of agricultural
chemicals and such programs will bring about the need for newer and better
chemicals. This need presents an opportunity for the agrichemical industry
we, are interested in our environment and have been active in the national
pesticide monitoring program since 1967.
Many stresses work to overcome man. Yet, the nearly four billion people
on the earth today have about 20% more food per person than did the 2.7
billion people of 20 years ago. Are we satisfied with this record? No.
Many millions of people are still starving.
-------
America is a land of beauty - especially where food is grown. And
our fanners have been good stewards of the soil. But we do have
problems. Every field has problems, often hidden stress that farmers
must overcome. All stress begins with the soil, sunshine, and moisture,
because all life depends on them. God has slowly, but surely allowed
us to create tools to cope with stress. We should not throw .them away,
but we should learn to use them more wisely, and build on them. Good
seed, fine agricultural machines, fertilizer, agricultural chemicals,
better cultural practices, and biological control are all tools we cannot
neglect if we expect to survive. This is what modern agriculture is
all about — survival. We cannot go back to the 1800's or even the early
1900*s. We must continue on a course of progress. We have made a lot
of mistakes, but we've done a lot of things right. We have a good agri-
cultural industry, let's improve it. We have a high quality environment,
let's improve it. The two objectives are compatible and, for the
benefit of our children and their children, they are essential.
DISCUSSION
QUEST I Oil: What is the involvement of the pesticide indsutry in monitoring
the fate of chemicals in the environment?
TWEEDY: CIBA-GEIGY has been monitoring the presence of our chemicals
in water and in soil•for quite some time and the industry as a whole has
also been.
QUESTION: We have been talking about integrated pest management. I spent
many years developing a very successful integrated control program on
cotton in California. The program was initiated after a disaster occurred
with cotton bollworm which was precipitated by chemical controls used against
the lygus bug. 'Then, two or three years ago, there was an advertisement
for an insecticide called Supracide. It was broadcast on a Central Valley
radio station and it went something like this: "Mr. Farmer, the lygus
bug is about to invade your fields. At the very sight of the lygus bug
start spraying with Supracide. Get on a regular program and you will
have a cleaner crop and more profit. " Bow do you equate this kind of
thing with the glorious views and interests expressed by the agrichemical
industry about IPM?
TWEEDY: We are trying to be much more careful about how we recommend
~he use of pesticides in pest management programs. As a matter of fact,
we just recently took one off the market that was very good because we
were not sure how to use it. This was a voluntary action on our part. Since
that time we have done a considerable amount of research ar.d found it does
fit into a. pest management program, 'fie put it back on a limited basis for
a par-ijular test management project. I do think we're becoming more
responsible as an industry, but, I won't deny that we are going to con-
tinue to try -2nd make a profit by selling a product and will continue to
-SHjcurage farmers to buy that product.
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96
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Part Four
implementation
97
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98
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OF INTEGRATED PEST MANAGEMENT PROGRAMS
Leon Moore
Extension Entomologist
University of Arizona
Tucson, Arizona
INTRODUCTION
What is pest management? What makes it suddenly so important—even
popular? How and when did it start? Why should I understand it? Is
it compatible and usable in today's technical agriculture?
Pest management brings together into a workable combination the best
parts of all control methods that apply to a given situation. A some-
what more scientific definition of pest management would be: the practical
manipulation of pest populations using sound ecological principles. The
emphasis here is on practical and ecological. There are many ways of
controlling insect pests, only a few of which are practical, and fewer
yet ecologically sound; that do not create a worse situation. Pest
management then, is "putting it all together" —using the best combination
of control techniques that permits us to "live" with the pest while sus-
taining non-economic losses.
Pest management as a concept is not new; only the name is. Many of the
components of a sound pest management system were known some 50 years
ago through the research of Isely in Arkansas. His extensive and fore-
sighted work with cotton insects in the mid 1920's was sufficient to
provide a sound basis for today's pest management. His management of
such pests as the boll weevil, the bollworm, and spider mites, was based
on the principles of applied ecology, a vital component of pest management.
Why is insect pest management needed? Why not continue to control insects
as they have been in the past? The answers to these questions are some-
what complicated and yet they must be dealt with and understood.
Introduction of the organochlorine insecticide, DDT, began an era of
insecticidal control of insects. Entomological research and extension
work largely emphasized the use of insecticides to control insects. One
new insecticide followed another and new groups such as organophosphates
and carbamates made cheir appearance. Insecticidal control provided a
quick, inexpensive and convenient method of controlling insects. It
greatly slowed or stopped efforts such as Isely's to develop methods of
insect control which were forerunners to the methods which we are using
in our insect pest management systems today.
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There were many reasons for the need to resume emphasis on the devel-
opment of insect pest management. These were brought to light as prob-
lems began to occur resulting from large scale use of insecticides.
One of the first problems was the development of resistance or toler-
ance by certain insects to insecticides used against them. Beginning
with the resistance of houseflies to DDT, this problem has continued
to increase until today about 250 species have shown resistance to
certain insecticides and some are resistant to one or more groups.
After a few years of widescale use of insecticides, the problem of
residues remaining in food and feed crops, in the soil, and in animals
became known. Some insecticides such as the organochlorines are highly
persistent because of their chemical stability. Others such as the
organophosphates are less persistent and rapidly degrade into harmless
compounds. In order to cope with the residue problem, growers found
it necessary to use the more toxic but non-persistent compounds.
The shift from persistent to non-persistent insecticides has helped
to relieve the problem caused by remaining residues but has been largely
responsible for the occurrence of other problems. The non-persistent
Insecticides are generally more toxic, creating an additional health
hazard to persons handling and applying them. They also are generally
broad spectrum, i.e. toxic to many insect species in the treatment area,
and require more frequent applications to maintain insect control.
This has resulted in a disturbance of pest-beneficial insect relation-
ships, permitting pests of minor importance to rise to major pest status.
It has also resulted in increased costs since the less persistent insecti-
cides are generally higher priced and more applications are required.
These factors have contributed to the need for developing pest management
systems which emphasize alternative methods of control and minimize the
use of insecticides.
BASIC ELEMENTS OF INSECT PEST MANAGEMENT
Four 'elements basic to the development of a pest management program are
sampling, economic levels, natural control, and insect biology and eco-
logy. A good sampling system is extremely important in that it provides
information on insect numbers in each field and must be developed to serve
as a base for utilizing knowledge of natural control, economic levels,
and the biology and ecology of the major insects involved. Once the samp-
ling program is established, these basic elements can be dovetailed to-
gether to serve as the foundation upon which practical components can be
added to the total pest management program.
Before a pest management program can be initiated a great deal of basic
information must be accumulated. This includes information about the
agroecosystem, such as the crops grown, agronomic practices employed, soil
type, irrigation water, and any other' factor which relates to the production
of the crops in the system. Detailed information must be available on the
major peats and beneficial insects found in the agroecosystem in order to
understand the seasonal occurrence and magnitude of all species of concern.
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The integration of all information on the agroecosystem itself with
that on the biology-and ecology of the pests and beneficial insects will
provide significant insight on natural control in any particular area.
The level of natural control provides the base on which all management
practices are built, some of which enhance natural control.
PRACTICAL COMPONENTS OF INSECT PEST MANAGEMENT
When the basic elements have been established to form the foundation
for the insect pest management system it is possible to build a solid
and effective program on this base. There are several single-component
control methods that can be incorporated into a multifaceted insect pest
management system. These methods have been, for the most part, used
individually for control of specific insect pest problems. The combi-
nation of several of these into a comprehensive insect pest management
program- can provide better suppression of key pest species, and, at the
same time, place less demand on any one method. The methods currently
available and proved effective are: cultural control, biological control,
chemical control, host-plant resistance, mechanical-physical control,- and
regulatory control.
The number of components that can be used in an insect pest management
system is limited only by their practical availability. If the available
components are to be used most effectively, emphasis must be placed on
their use at the appropriate time. Some components are applied when the ,
pest is a problem in the field while others are applied at times whin the
pest is overwintering or when it is at sub-economic levels. Generally,
full utilization of all non-chemical methods should be emphasized on a
year-round basis and insecticides should be utilized as a means of reducing
populations that have reached or exceeded the economic level.
Several potential components are in various stages of development at the
present time. These include pheromone control, microbial control, chemo-
sterilant control, and other control methods. These should become impor-
tant parts of insect pest management systems as they are developed to the
point of being practical for use.
EXAMPLE OF AN INSECT PEST MANAGEMENT PROGRAM: COTTON IN ARIZONA
Emphasis in cotton pest control programs in Arizona has been aimed pri-
marily at developing or adapting a cotton scouting program to the state
which would serve as the basis for an insect pest management system. Two
prerequisites to the effective practice of pest management are: good field
sampling; and confidence in and use of sound economic levels of pest popu-
lations or damage.
Four pest management programs involving four major Arizona cotton producing
counties were conducted in 1977. Counties involved included Graham, Final,
Pima, and Maricopa. About 50,000 acres of cotton were included in the
programs which were entirely grower financed. In addition to cotton, the
program in Pinal county continued the multicrop approach and involved
7,400 acres of other crops including small grains, sugar beets, alfalfa,
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and grain sorghum. TJie Final County Growers Pest Management Corporation
employs a full-time supervisor and part-time secretary and bookkeeper in
addition to the necessary scouts to keep their program on a year-round
basiss. A new program established under a private consultant in Marlcopa
county operates on a year-round basis and involves other crops grown in
the area. Programs in other areas operate only during the cotton growing
season. Growers continue to request Extension Service involvement in the
operation and development of their programs.
Grower involvement has increased each year since the pilot program was
initiated in Pinal county in 1971. About 95% of the 1977 growers followed
pest management principles compared to 222 when the program started in 1971'.
Some of the changes brought about include:
1. ' Increased involvement of growers in pest management;
2. Establishment of grower organizations to operate pest management
programs;
3. Full financing of programs by growers;
4. Increased number of private consultant firms for pest management
purposes;
5. Year-round practice of pest management through the multicrop approach;
6.' Utilization of the sex pheromone gossyplure for early season mass-
trapping and monitoring of pink bollworm males;
7. Better utilization of naturally occurring beneficial insect populations
in pest management;
8. Use of resistant varieties;
9. Harvest management of alfalfa to reduce lygus migration into cotton;
10. Treatment of safflower with Insecticides to reduce lygus numbers and
the subsequent problem In cotton.
Acceptance of pest management by growers is indicated by its continued growth
in Arizona. The new program established in Maricopa county gives pest man-
agement good exposure in all the major crop producing areas of the state.
About 150 growers participated in 1977 compared to 140 in 1976 and cotton
acreage increased from 44,000 to 50,000 acres. Other crop acreage amounted
to approximately 7,400 acres.
All programs are completely grower administered and financed although the
new programs still require much Extension assistance. Two grower groups
are operating as cooperatives while two programs are operated by contracting
with private consultants. The growers are eagsr to promote the development'
of pest management as evidenced by their acceptance and financing of the
sex pheromone trapping addition to the programs in 1975, 1976, and 1977.
This addition will be continued in 1978 at grower expense.
Grower benefits from I?M increase as the program in a county matures. This
is probably due to growers becoming more familiar with pest management objec-
tives and £o greater confidence in program personnel. Growers become more
involved each year they participate and this also adds to grower benefits.
Of special interest is the overall reduction of grower costs by reducing
insecticide use which also contributes to environmental quality. In Pinal
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in 1977 was about 7.8 compared to approximately 9 in 1971 when the pro-
gram began. 1977 was a severe cotton insect year and 15 or more treat-
ments were common by growers outside the programs. The 44 program growers
in Final county spent an average of $54.87 per acre for insect control
while it is estimated growers outside the program in Maricopa, Final and
Yuma counties spent an average of $100.00 per acre. In comparing treat-
ment costs one must keep in mind that insect populations and the need for
control varies from year to year. Pest management enables the growers to
take advantage of light infestation years, however, as well as as reducing
pest control costs during years of serious pest outbreaks.
In Graham county, only 6,500 of 15,000 acres were treated in 1977. \ll
the acreage was treated on a pre-scheduled basis prior to establishment
of the pest management program in 1969. Growers are pleased with the
program because of the low cost for insect control and the .improved rela-
tionship they have with the general public in their communities. Another
spin-off from the program has been improvement in the honeybee industry.
One beekeeper stated that the program increased his income about $20,000
a year. Tables 1 and 2 give a summary of IPM Program results in Graham
and Final counties respectively.
1973
Program Acras 5,487
Sprayed Acres (local) 45,618
Scouting Coat $ 7,806
Spraying Cost (Material ami $152,100
application)
Ph«romoa« Trap Cose
Total Cost $162,906
Total Coat P«r Program Acre $29.69
1974 1975
11,076 7,634
4,930 1,957
$18,386 $U,823
$26,946 $11,032
S 15, 267
$45,332 $40,122
$4.09 $5.26
1976
8,014
290
$16,685
$ 1.538
$32,056
$50,179
$6.26
1977
15,560
25,510
$32,000
$127,590
$70,020
$229,610
$14.75
Table 1. Information Summary for Graham County IPM Program
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-
Grovsra
Flalda
Acraa
Fields Sot Traatad
Acraa Hoc Traatad
Acrta Traatad
Total Acra Traaemanta
Rang* of Treatments
Avg. Number Treatment*
Per Acre
Totml Cose of All Acre
Treatments
Atrg. Total Co«t Par
Acr« T;a*cad
E»t. Coat of Material
And Application/ Acra
1971
Jl
387
15,260
6,390
56,232
1-13
8.8
$196,812
$ 30.80
$ 3.50
1972
60
480
19.313
12
95
18,115
173.330
0-16
8.9
$606,655
$ 33.49
$ 3.50
1973
85
722
31.582
29
982
29,995
156,563
0-12
5.2
$626,252
$ 20.88
$ 4.00
1974
54
503
21.458
16
687
20,431
106,252
o-io
5.2
$531,260
$ 26.00
$ 5.00
1975
35
295
12,742
8
165
12,577
75,222
0-U
5.7
$451,322
$ 35.88
$ 6.00
1976
41
435
19,172
57
2,022
17,150
65,772
0-10
3.4
$394,632
$ 23.01
$ 6.00
1977
44
471
20,761
0
0
17,845
139,890
1-15
7.8
$979.230
$ 54.87
$ 7.00
Table 2. Information Summary for Final County Pest Management Program
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ECONOMICS OF PEST MANAGEMENT
Dr. Ray Frisbie
Department of Entomology
Texas A&M University
It is indeed a pleasure for me to attend this Pest Control Strategies
Conference to discuss the economic implications of pest management
programs with you. I have been requested to address my remarks primarily
to the area of cotton integrated pest management programs. This area of
evaluation is most comfortable to me and I think has, as we will see in
subsequent discussion, been most productive in the area of economic evalua-
tion of both research and implementation of IPM strategies. There will
be no attempt to define integrated pest management. This concept has
been defined many times and should be more properly presented as a
philosophy rather than a clear cut definition. The responsibility of all
IPM systems is to present the participants involved with a fair and a
reasonable profit. In addition, IPM has a responsibility to man and his
environment, i.e., to minimize as much as possible the introduction of
hazardous chemical toxicants into the environment. With these two broad
goals in mind, we should address the area of economics with the basic
assumption that most of the strategies developed for IPM are done so with-
in the economic concept.
The understanding of the economic threshold is basic to IPM systems. If
insect populations are allowed to increase to economically damaging levels,
then there is usually no other alternative than the application of an
insecticide to prevent or reduce economic loss. IPM strategies must bring
all population suppression measures to bear prior to the time populations
develop and pass the economic threshold level. The components of an IPM
system should be integrated in such a way that the various pest population
suppression or regulation factors would ideally prevent or minimize the
use of insecticides. However, the state of sophistication of most IPM
systems, particularly in cotton pest management programs have not reached
the stage of sophistication where chemical insecticides are not required.
In certain instances, IPM systems have been developed that use less in-
secticides with relatively little environmental disturbance. However,
in those areas where populations have risen above economic threshold levels,
chemical insecticides have and will for some time in the foreseeable
future play a key role in the management of insect populations.
COTTON IPM PROGRAMS
The economic and environmental assessment of IPM programs must be included
as a key component in all research and implementation stages. A careful
economic track record must be kept to determine the feasibility of the
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various research and implementation approaches. Cost/benefit ratios
should be developed and a clear indication of the impact-of IPM strategies
on net profit must be determined. Several excellent examples of the
economic feasibility of IPM research systems have been demonstrated. This
research was developed with a systems approach to better understand
the various' components involved in the economical management of insect
pests. An IPM system in the Lower Rio''Grande Valley of Texas utilized
a short-season, indeterminate cotton variety (Tamcot SP-37) in combi-
nation with reduced fertilizer and irrigation use, and field scouting
reports to assist in decisions to apply insecticides on an as-need-basis
(Namken and Heilman 1973). Additional research also included a-variation
in the row width utilizing the short-season cotton genotype. This study
was cpmpared with conventional methods of irrigated cotton production in
the Lower Rio Grande Valley. Insecticide costs decreased by $10.14
per acre under the IPM program. Annual'insecticide costs for conventional
cotton were approximately $28.91 per acre compared to $18.77 for the
short-season, narrow-row system. Net returns for conventional production
were estimated to be $37.27 per acre while under the IPM program net
returns were estimated to be $55.77, or an increase of $18.50 per acre
(Lacewell et al. 1977). A similar short-season, narrow-row cotton study
was conducted in Frio County Texas in 1974. An evaluation of this study
using \the short-season cotton Tamcot SP-37, narrowing the row width to
26 inches, and reducing nitrogen fertilizer levels and irrigation water,
showed that pesticide applications were reduced to an average of 6.6
applications as compared to conventionally grown cotton that averaged
16.9 (Sprott et al. 1976). Further analysis indicated that the short-
season, narrow-row system returned a net profit of $252 an acre as com-
pared to $109 per acre for conventional cotton grown on 40 inch rows.
A research and demonstration project conducted in the Trans-Pecos of
West Texas has provided some interesting opportunites for economic pro-
duction of cotton (Lindsey et al. 1976, Condra et al. 1978). An econo-
mical (production system was developed for the Pecos River Valley. A
complete economic study was conducted prior to the initiation of the
plan juxtaposed with the production factors chat impinged on the growth
and management of cotton. This system was termed ECONOCOT and was
developed out of a need to increase profitability of cotton production
in the Pecos River Valley. Increased prices in natural gas for well
pumps,1 high insecticide use and overall inflated production costs have
produced a gradual decline in the cotton acreage in the Pecos River
Valley since the early 1970s. A research-demonstration study that
included all variables in the economics of cotton production was con-
sidered and the results of that were quite revealing. 'Short-season
indeterminate cotton varieties (Tamcot SP-21), an intermediate
naturfng cotton variety (McNair 612) and 2 long-season indeterminate
varieties (Stoneville 213 and Deltapine 16) were compared under different
management schemes. Using reduced fertilizer and water inputs along
with timed insecticide applications based on economic threshold in-
formation, the total pest management package demonstrated quite clearly
that the shore-season cotton Tamcot SP 21 returned $364.38 per acre
compared with net returns generated for Stoneville 213 and Deltapine
16 of $134.49 and $108.19, respectively (Lindsay ac al. 1976).
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Perhaps one of the best examples of the economic impact of an applied
pest management program is seen in the Texas Cotton Pest Management
Program conducted through the Texas Agricultural Extension Service.
Texas Cotton Pest Management Program objectives included the judicious
use of pesticides based on economic thresholds as determined by field
inspection (scouting), conservation of beneficial insects, introduction
of new technology into a total systems approach for the overall manage-
ment of insect pests. The results of the economic evaluation for the
Texas Cotton Pest Management Program have been well documented (Frisbie
et al. 1975). In a comparison of farmers participating in the Texas
Cotton Pest Management Program with a similar group of non-parti-
cipating farmers, total net profits for 1973 and 1974 in the 35,000
acre program increased approximately $2,100,000 due to increases in
yield and decreases in insecticide use, or both. Concurrently there
was a reduction of 82,000 Ibs. of pesticides entering the environment
during the 1973 and 1974 production season (Frisbie et al. 1974).
A similar economic evaluation was used to evaluate the expanded Texas
Pest Management Program in 1976. Increase net returns were calculated
to be $5,594,000 for 100,000 acres of cotton included in the Texas
statewide IPM program in 1976 (Frisbie 1978 unpublished data).
SUMMARY
The results of these evaluations clearly indicate that IPM has a strong
economic and environmental base. As we proceed forward in the im-
plementation of IPM programs, it is essential that the position of
IPM be clearly placed in the context of a total agricultural production
cropping system. It is also strongly suggested, as we develop into the
area of medical/veterinary and urban entomology, that similar evaluation
schemes be developed prior to or at least during the early stages of
implementation.
DISCUSSION
QUESTION: Row do you get farmers to make the transition to short-
season cotton?
FBISBIE: Cur philosophy is that it is best to deal with an educated
man. 'fie spend alot of time and energy educating the farmer. If you
can show the farmer a way to make more money and farm better, he will
most likely listen. The cost of insecticides, particularly if you get
into a bollworm fight, are just prohibitive. Xe have areas of Texas where
they chose to go bankrupt rather than change and we have areas_ of Texas
where they are changing radically to this short-season system.' Yields
have increased and cotton production across large areas has stabilized.
Insecticide use has gone down and the industries in those areas have
come back into viability.
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REFERENCES
Namken, L.N., and N.D. Heilman. 1973. Determinate cotton cultivars
for more efficient cotton production on medium textured soils in
the Lower Rio Grande Valley of Texas. Agronomy Journal Vol. 65 pp.
953-956.
Lacewell, R.D., J.E. Casey, and R. Frisbie. 1977. An evaluation of
integrated cotton pest management programs in Texas: 1964-1974.
Departmental Technical Report No. 77-44 Texas Agricultural Experiment
Station, pp. 34-44.
Sprott, J.N., R.D. Lacewell, G.A. Niles, J.K. Walker, and J.R. Ganaway.
1976. Agronomic, economic, energy and environmental implications
of short-season, narrow row cotton production. Texas Agricultural
Experiment Station, MP-1250. 24 p.
Lindsey, K.E., G.D. Condra, C.W. Neeb, L. New, H. Buehring, D.G. Foster,
J, Menzies. 1976. Texas ECONOCOT system upland cotton demonstration
in Pecos County 1976. Texas Agric. Ext. Serv. Unpublished memo.
Condra, G.D., K.E. Lindsey, C.W. Neeb, and J.L. Philley. 1978.
ECONOCOT...A Ray of Hope for the Pecos Valley. Texas Agricultural
Progress. Vol 24:3p.
Frisbie, R.E., J.N. Sprott, R.D. Lacewell, R.D. Parker, W.E. Buxkemper,
W.E. Bagley, and J.W. Norman, Jr. 1975. A practical method of
economically evaluating an operational cotton pest management
program in Texas. J. Soon. Entomol. Vol 69:2 pp. 211-214.
Frisbie, R.E., R.D. Parker, D.E. Buxkemper, W.E. Bagley, and J.W. Norman,
Jr. 1974. Texas Pest Management Annual Report, 1974, Cotton,
Texas Agricultural Extension Service. Unpublished mineo.
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POLICIES ON PESTICIDES
Charles Reese
Office of Pesticide Programs
Environmental Protection Agency
Washington, O.C.
HISTORICAL PERSPECTIVE
Recently chemicals were developed which gave the American farmer a
means of controlling pests at low cost. Some of these chemicals
provided spectacular results and were persistent enough to give long-
term crop protection, causing many users to drop the more traditional
preventative forms of pest control. This increased dependence on the
use of pesticides has led to pest resistance, secondary pest problems,
undesireable crop residues, and non-target effects. Federal policies
developed since World War II, resulted in pesticides being the major
control tool available for use by pest managers. These successful
policies were related to cheap and abundant supplies of land and energy.
Today, less land, increased energy costs and environmental concern
necessitate a shift in Federal policies. A look at past pesticide
policies and programs is necessary to understand the emerging Federal
policies concerning pesticides.
In 1910 the Federal Insecticide Act gave the Federal government the
authority to remove fraudulent or misleading materials from the market.
In 1947, the Federal Insecticide Fungicide and Rodenticide Act was
passed to regulate the marketing of economic poisons and devices. To-
gether with amendments made in 1959, 61 and 64, the Federal Insecticide
Fungicide and Rodenticide Act defined the term "economic poison" as
having the same meaning as the more commmonly used term "pesticide1.1
It is defined in the Act as "any substance or mixture of substances
intended for preventing, destroying, repelling or mitigating any insects,
rodents, fungi, weeds and other forms of plant and animal life viruses,
except viruses on or in living man or other animals" declared to be
a pest by the Administrator and "any substances or mixture of substances
intended for use as a plant regulator, defoliant, or dessicant."
"Devices" are mechanisms such as ant traps, sold together with pesticides
for the purpose of application; or simply mechanisms such as electronic
bug-killers, designed to destroy pests.
Under the Federal Insecticide Fungicide and Rodenticide Act, the United
Scates Department of Agriculture required that:
1. All pesticides shipped interstate be registered. Adulterated,
misbranded or insufficiently labeled products were prohibited
from interstate commerce.
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2. Registration was granted for five years when test data
proved the pesticide safe and effective when used as directed
on the proposed lable.
3. Use directed on the label for food and feed could not result in
pesticide residues greater than proposed residue tolerances-
until 1970 under the Food, Drug and Cosmetic Act - Health,
Education and Welfare.
4. Lables of highly toxic chemicals were required to contain the
word poison and describe the antidote.
In 1954, the Miller Amendment (Sect 408) to the Food, Drug and Cosmetic
Act authorized the Food and Drug Administration of the Department of
Health, Education and Welfare to set tolerances on pesticide residues
on raw food. Some pesticides were registered on a negligable residue
basis. As the techniques of chemical analysis became more sensitive,
residues were detected and it became necessary to decide if these newly
discovered residues were a hazard to public health. In 1965 the National
Academy of Sciences - National Research Council recommended that the
concept of uagligable residues as used in the registration and regulation
of pesticides be abandoned. A joint United States Department of Agricu-
ture-Health, Education and Welfare implementation of the National Research
Council report was published in the Federal Register on April 13, 1966.
It was agreed that registrations of all uses involving reasonable ex-
pectation In the absence of a finite tolerance or exemption would be
discontinued as of December 31, 1967. Many registrants did not submit
for tolerance for certain crops; as a result, many uses were cancelled.
Other registrations for zero tolerance pesticdies continued on the basis
of pending petitions for a finite tolerance or on the basis of progress
reports on ongoing studies. A 1974 report found that the resolution of
this question was a social decision.
In 1958, the Delaney Clause was added to Sect 409 of the Food, Drug
and Cosmetic Act. This addition to the food additives section states
that no food additives capable of causing cancer when ingested by
animals or man may be added to food. Then in 1969, the National Environ-
mental Policy Act was passed'. The National Environmental Policy Act
requires Federal agencies which use pesticides to incorporate a concern
for the quality of the environment into agency missions. In addition,
the National Environmental Policy Act established the Council on En-
vironmental Quality. The Council on Environmental Quality supervises
environmental impact statements which require Federal agencies to con-
sider alternative actions, solicite advice from other Federal agencies
with expertise and consult with Council on Environmental Quality. These
environmental Impact statements have had an effect on Federal pesticide
use policies. Specifically, the application of pesticides in water areas
or non-problem areas is now being avoided.
Reorganization Plan #3 established the Environmental Protection Agency
December 2, ^9,70. The Environmental Protection Agency was designated
as the central Federal pollution abatement agency responsible for the
protection of the environment against all types of harmful pollution,
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specifically including pesticides. The Environmental Protection Agency
has been given pesticide regulatory responsibilities previously scattered
through a number of Federal agencies. The transfer of responsibilities
included:
1. Pesticide Registration from the United States Department of
Agriculture.
2. Tolerance setting for pesticide residues on food and feed from
the Food and Drug Administration of the Department of Health,
Education and Welfare.
a. Responsibility for enforcement of pesticide residues on raw
agricultural products remains with the Food and Drug Ad-
ministration while like responsibilities for pesticide
residues in meat and poultry in interstate and foreign
commerce rests with the United States Department of Agri-
culture (Animal Plant Health Inspection Service).
b. Regulation of pesticide product advertising is the re-
sponsibility of the Federal Trade Commission.
c. The Department of Transportation is responsible for pesticide
packaging.
3. Certain technical assistance and research functions from the
Public Health Service of the Department of Health, Education and
Welfare.
4. From the Department of Interior:
a. Federal Water Pollution Control Act functions
b. Pesticide Research Act functions
c. Activities of the Gulf Breeze Biological Lab.
As you know, the Environmental Protection Agency at its inception focused
on the hazards of pesticide pollution. At a time when an increasing
Federal role was called for, the Environmental Protection Agency was operating
under enabling legislation designed at an earlier time for programs of
other agencies with somewhat different missions.
This situation set the stage for the amendments to the Federal Insecticide,
Fungicide and Rodenticide Act in 1972 and 1975 which gives the' Environmental
Protection Agency authority to:
1. Control all pesticide use.
2. Classify pesticides.
3. Approve certification of applicators of restricted use pesticides-
Department of Transportation (Federal Aviation Administration)
is responsible for aerial applicators.
4. Conduct research on biologically compatible alternatives, for
pest control.
5. Make integrated pest management information available.
These congressional mandates make clear the responsibility Federal agencies
have to use and advise the use of pesticides in the most efficient,
environmentally sound manner possible. In his environmental message to
Congress, the President has asked for the development of a Federal policy
on integrated pest management. The Council on Environmental Quality at
the conclusion of its ongoing review of integrated pest management in the
United States has been asked to recommend actions which the Federal govern-
ment could cake to encourage the development and application of pest
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management techniques which rely on chemical agents only as needed. In
this regard, Secretary Bergland has pointed out that the need for a
systematic approach to commodity protection based on sound economic,
ecological, technical and societal considerations is essential for main-
taining agricultural production in the United States. He went on to
say that "Each system must be economical and compatible with other farm,
forest and urban horticultural management practices." I would like to
briefly summarize on-going Federal agency activities in the development
of responsive pesticide policies.
FEDERAL AGENCY ACTIVITIES IN HM
Council on Environmental Quality (CEQ)
As an advising body to the President, the Council on Environmental
Quality provided the first Federal Policy statement on integrated pest
management. The Council on Environmental Quality has been asked to
update the status of integrated pest management and then recommend to
the President policies and actions the Federal government could take to
encourage the development of integrated pest management.
United States Department of Agriculture/University Complex
Historically, the vast majority of pest control research, development and
implementation has originated from this source. Programs conducted in-
clude development of techniques of biological, cultural, chemical,
and crop varietal methods of control as well as pest population sur-
veillance. Recent programs have been initiated aimed at gaining farmer
acceptance and use of integrated pest management. The United States
Department of Agriculture has the lead responsibility for the development
of new integrated pest management technologies.
Department of Health, Education and Welfare (HEW)
Health, Education and Welfare along with several universities here and
in Canada has been working to improve career opportunities in integrated
pest management through symposia, curricula development and vocational
training. Comprehensive integrated pest management curricula for community
and junior colleges have been developed. Health, Education and Welfare
in cooperation with other Federal agencies is developing an integrated
pest management education program for secondary schools. The program in-
cludes basic information dissemination and general education of urban
and rural dwellers concerning their ecosystem. Pest problems and their
control are to be part of full scale implementation of a comprehensive
integrated pest management educational program. This program here is an
example of Health, Education and Welfare initiatives.
Department of Housing and Urban Development (HUD)
,This department has become increasingly involved in the further develop-
ment and implementation of integrated pest management. Along with
developing a manual on pest management, Housing and Urban Development
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Is planning for the development and Implementation of integrated pest
management in public housing and especially as part of housing re-
habilitation projects.
National Science Foundation (NSF)
The National Science Foundation has been a continual supporter in the
development and implementation of integrated pest management programs.
In cooperation with the Environmental Protection Agency and the United
States Department of Agriculture, the National Science Foundation has
sponsored projects to test the practical use of Integrated Pest Management.
Department of State, United States Agency for International Development
The United States Agency for International Development (AID) is colla-
borating with the University of California (UC) to develop and utilize
integrated pest management methods for crop protection throughout the
world. Its objectives are to promote ecologically sound crop protection
tactics, to develop grower capabilities for making sound pest management
decisions, to improve the socioeconomic position of farmers by in-
creasing the quantity and quality of commodities produced to the consumer
and to maintain the quality of human life.
National Academy of Sciences (NAS)
The National Academy of Sciences has had a strong interest in the develop-
ment of pest control technology. Over the past few years the Academy has
played a major role in promoting integrated pest management programs by
making available several publications outlining the latest pest manage-
ment methods. The National Academy of Sciences continues to provide
valuable assistance through its continual assessment of the state of
development and implementation of pest management programs.
Department of Defense (DOD)
Working through the Armed Forces Pest Control, the Board Department of
Defense develops pest control manuals, trains pest control personnel and
is responsible for pest control related to military bases and activites.
Environmental Protection Agency (EPA)
The Environmental Protection Agency has been carrying on programs related
to the development and implementation of integrated pest management pro-
grams. In the developmental phase, this Agency has the responsibility
to: (1) Register and Control the use of pesticides and (2) develop bio-
logically integrated alternatives for pest control. As a part of im-
plementation, Environmental Protection Agency continues to make instructional
materials concerning integrated pest management available upon request
in cooperation with the United States Department of Agriculture, the Council
on Environmental Quality, the Department of Housing, Education and Welfare
and the Department of Health, Education and Welfare.
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Integrated Pest Management may prove to be a way of avoiding the can-
cellation of some pesticide uses in the areas of experimental use
permits and later the registration process itself will be examined as
a means of responding to public concern and Agency responsibilities.
Some Federal pesticide use policies which may be expanded are:
1. One Federal policy on integrated pest management - not an
agency by agency effort.
2. Organization of pest control research and development as
pest control systems.
3. Improved access to all information pertaining to pest, pest
control techniques and integrated pest management systems.
While integrated pest management is not an across the board
panacea, existing management options should be available to
those concerned and certainly problems should be known to
those with responsibilites or incentives to solve or reduce
them.
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DISCUSSION
QUESTION: lou mentioned the requirements regarding the use of pheromones
and hormones. What are those requirements?
REESE: Some people feel these third generation pesticides are "good"
things and should be zipped through the registration process. If, on
the other hand, you have to sit in the registration division, you probably
have a different feeling about it, a different kind of responsibility.
Desman Johnson, who heads the pesticide program, is pushing very hard to
get this and other parts of the registration process moving ahead faster.
We have been held up by court cases and disagreement over different points
of view. Whatever the compound, we want to see that people are aware of
what the requirements are and also that these materials move- through the
registration process faster.
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USDA. PERSPECTIVES CN PEST MANAGEMENT
R.L. Ridgway
Federal Research, Science and Education Administration
United States Department of Agriculture '
Beltsville, Maryland '
MISSION !
I appreciate this opportunity to share with you some thoughts on pest
management from the perspective of the U.S. Department of Agriculture.
As you know, USDA is involved in a number of pest control activities
including: (1) mission-oriented fundamental research, (2) applied re-
search to develop pest control tactics, (3) research to develop decision-
making technology to aid in determing when control methods are' needed,
(4) integrating tactics into management systems, (5) evaluation of
economic feasibility, (6) extension and technology transfer, and (7) re-
gulatory and action programs. These activities are conducted in coopera-
tion with other Federal and State agencies and the private sector.
HISTORY
Pest management and integrated pest management may be new terms to many,
but some of the underlying concepts have long been recognized. Before
the advent of modern synthetic organic pesticides, cultural and biologi-
cal methods of controlling pests were common, and they remain today the
primary means of controlling disease and nematodes, and, to a lesser
extent, insects and weeds. For example:
(1) A lady beetle predator that completely controlled the cottony
cushion scale on citrus in California was imported by USDA in 1888.
(2) Varieties of wheat that were rust resistant were developed in
the early 1900'a. Later, resistant varieties of wheat were
integrated with optimum planting dates to control Hessian fly.
(3) In the 1930's an integrated approach was used in a cooperative
Federal-State-grower program to control the phony peach disease.
However, the synthetic organic pesticides that were available following
World War II provided effective, economical, and convenient pest control.
As a result, pesticide use increased rapidly and played a dramatic role
in increasing agricultural production. Less emphasis was therefore placed
on nonchemical pest control. But even during this period, pest control
on forage and small grain crops continued to emphasize cultural and
varietal resistance because these methods had such low cost.
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Indeed, as early as the late 1950's, the USDA expressed concern over
problems that were arising because of pest resistance to' pesticides and
the adverse effects of pesticides on the environment. Therefore, at
this time, the Federal Research unit (formerly the Agricultural Re-
search Service) of the Science and Education Administration began to
revise its research program. By 1970 approximately 80 percent of its
insect and plant disease control budget was directed toward fundamental
biology and alternative methods of pest control. However, the general
effectiveness and low direct cost of pesticides (herbicides, insecticides,
fungicides, nematicides) compared with alternative control methods,
encouraged the expansion of pesticide use until, at the present time,
over one billion pounds per year are being applied in the United States.
Market value of pesticides has also greatly increased.
The public concern over pesticide use in this country continues to in-
crease and has resulted in the development of comprehensive pesticide
regulations to protect environmental quality and human health. Also,
pest resistance to pesticides has increased substantially. The aet
result is the great interest in pest management, which may reduce pesti-
cide use, pest control costs, and health risks and also may result in
improved environmental quality. In addition, it may delay the obso-
lescence of individual pesticides due to the development of resistance.
More emphasis is now being placed on selecting, integrating, and using
pest control tactics based on anticipated economic, environmental, and
sociological consequences rather than on routine pesticide treatments.
USDA ROLE IN EM
The U.S. Department of Agriculture strongly endorses the concept of
integrated pest management. The Department will continue to develop,
practice and encourage the use of those tactics, systems, and strategies
of practical, effective, and energy-conserving pest management that
will result in protection against the environment. Thus, the Department
will stress integrated approaches to pest management problems in its re-
search, extension, regulatory, and action programs. In the process,
the Department will be mindful of the interests and pest management
needs of all segments of American society including those interested in
gardens, households, small farms, commercial farms, forests, food and
fiber handling, and storage and marketing enterprises.
In order to insure top level policy pest management support, Secretary
of Agriculture Bob Bergland issued a Secretary's Memorandum on pest
managment. He emphasized "We will be placing increased emphasis on
controlling significant pest populations with biological and other natural
controls as well as with selective chemical pesticides." However,
he added, "the policy should not be interpreted as a move to eliminate
the use of the pesticides that U.S. agriculture is dependent upon,
because they are part of the integrated pest management approach...The
policy statement should be seen as an increased concern by the U.S.
Department of Agriculture for the health and well being of all Americans
and for the ecosystem of which we are a part."
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As part of Che Department's efforts to seek more desirable approaches to
pest control, USDA sponsored a special study team to review the status
and prospects of biological agents for pest control. This joint Federal-
State-industry effort provided a useful basis for future activities.
The final feport contains 11 recommendations aimed at expanding the use
of biological agents. Perhaps the following 2 examples will 'provide
some insight into actions needed to increase the use of biological agents:
(1) Expand the USDA's competitive grants/contracts research program
in order to focus expertise on existing or emerging solutions to pro-
blems through the use of biological control agents. Such a program would
provide support for qualified scientists, wherever located, including
educational institutions, research foundations, private investigators,
commercial enterprises, and Federal and State agencies.
(2) Provide additional technical assistance to potential users of
biological control agents and assess the need for various types of
incentives to private enterprise to encourage and hasten participation
in the development and use of biological agents for pest control. Such
assistance should be made available to pest management consultants,
grower cooperatives, and commercial production and distribution enter-
prises.
Although these and other needs were identified to encourage the develop-
ment of biological controls, many of these same principles apply to
other desirable control tactics such as pheromones and insect growth
regulators.
Clearly, the USDA is committed to integrated pest management, and
we are aware of many changes that need to be made for more effective
implementation. However, for integrated pest management to be effective,
it must become an integral part of a large number of different agri-
cultural production systems. The increasing diversity of agricultural
systems adds considerable complexity to the development of integrated
pest management systems fcr all situations. For example, traditional
commercial farms, now numbering about 2.7 million, are larger,
more mechanized, and fewer in number than ever before. At the same
time, the number cf farms concentrating on alternative agricultural
production methods has increased to about 500,000 and the number of
home gardens now exceeds 35 million. The more labor-intensive agricul-
ture production systems such as home gardens offer some unique oppor-
tunities for integrated pest management. More emphasis in this area
will require the involvement of a larger number of people.
As we look toward future integrated pest management in all segments of
agriculture and forestry, we see a need for strengthening research and
development, technology transfer, economic assessment, and implementa-
tion. Substantial resources are currently available for these activities,
It is important that we work with all interested parties in order to
affectively utilize these resources. The Executive Budget for fiscal
year 1979 recommends modest increases in integrated pest management
funds for biological controls- host plant resistance, and pest manage-
ment for small farms. With modest Increases in resources and more
effective use of current resources, we are looking forward to the ex-
panded use of integrated pest management.
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DISCUSSION
QUESTION: Why do you place move emphasis en -integrated pest management
in home gardens than you do for ornamental plants?
RTDGWAY: At the present time, there is probably more support in USDA for
expansion in the home gardening aspect since it is more closely related
to food production. Also, there is a new major thrust on small farms
proposed within the USDA. In the Executive Budget for fiscal year 1979,
there is a 3.S million dollar increase request focusing on small farm
technology. Much of this effort can impact on home gardeners. In
addition, the Extension Service is currently funding a number of home
garden pilot projects. I have been putting some of my personal efforts
into involving USDA in the small farm and home garden area. I feel this
is the easiest place to make the transition into urban pest management,
In preliminary planning for the increased research, we have identified
a number of linkages that can be made with interested groups that USDA
has not actively served in the past. However, at the present time,
a number of our land-grant universities, including Cornell University
and Perm State University, are conducting research in the home garden-
ing area.
It is my hope that USDA can presently do more about pest management on
horticultural crops and in home gardens: If Congress supports an in-
crease in this effort beginning in 1979, an increased effort will follow
on pest management for ornamental plants.
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MAKING THE TRANSITION TO AN URBAN IPM PROGRAM
Helga Olkowski and William Olkowski
Center for the Integration of the Applied Sciences
John Muir Institute
Berkeley, California
INTRODUCTICN
Since 1971 the authors have been developing programs to manage the
plant-pest-human interactions in urban areas. We gegan with urban
shade tree insect pest problems. Cooperating with us were the Parks
and Recreation and Public Works Departments of five cities in the
north central coastal and Sacramento valley of California (1,2).
During the last two years the project expanded to examine indoor and
structural pest problems, working with a school district (3). Currently
the Center for the Integration of Applied Sciences (CIAS) is involve!
in studying the management of a range of insect and disease problems
on non-tree ornamental vegetation as well as vegetables in backyard
and community gardens (4,5).
Our concern is the overuse and misuse of pesticides in urban areas.
Since integrated pest management (IPM) programs in agriculture generally
demonstrate pesticide use reduction, it seemed logical to explore the
application of the IPM approach to these other settings. At this point
we conclude that it is entirely possible and desirable to develop urban
IPM programs and that the consequent reduction in the use of toxic
materials is likely to be substantial wherever this is done (5). However,
the characteristics of urban areas require the modification of agricultural
models for such programs to be successful.
THE URBAN CONDITION
To briefly summarize the relevant differences between the two human-
designed systems, urban and agricultural: urban areas are characterized
by a greater density of people; greater diversity of vegetation and
microclimates; overlapping pesticide use patterns and jurisdictions
(for example, the same piece of turf may be treated by the homeowner,
the mosquito control agency and drift from sprays aimed at the municipal
shade trees); and, to a very great degree, the pest problems in urban
areas are those of nuisance or aesthetics rather than of economic con-
sequence. Where pest problems resemble agricultural situations the most,
as in backyard and community food fardens, the small-scale and recreational
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nature of the systems makes feasible and desirable intensive care and
alternative strategies to pesticide use.
The mineral and plant resources of the nation come from the countryside,
pass briefly through the hands of the city-dweller, and then make their
way to the dump, often the nearest body of water. Pesticides are an
example of a resource that follows this route. However, they differ
from other toxic materials that are inadvertently released into the
environment as a by-product of manufacturing processes or urban life-
styles. Most pesticides are compounds that have been deliberately con-
structed to interrupt and destroy living systems. Thus their use in
areas of great human density, particularly by relatively untrained
entomophobic homeowners, janitors, gardeners and the myriad of others
either casually or extensively involved in urban pest control, is a
special category of resource management.
THE OCMPONENTS OF AN URBAN HM PROOAM
From the above description of the salient aspects of urban areas it
can be seen that educational efforts are a necessary feature of IPM
implementation. Furthermore, research in urban IPM technology transfer,
from the IPM specialist to the political and maintenance personnel of
the system to be managed, must take on a distinctly interdisciplinary
approach. The ecologist-IPM specialist finds that incorporation of
techniques of analyses and integration, from such varied discipines as
sociology, psychology, political science, public education and business
management, becomes a necessary requirement (7,8).
The programs developed by our project so far have all had three major
components: delivery system, education and research. The delivery
system includes the monitoring of potential pest insect populations,
their natural enemies, and human behaviors that affect the pest problem.
The latter includes other horticultural activities such as watering,
fertilizing, pruning or mowing, mulching, plant selection, etc., human
food storage and waste management methods, and systems for training,
deploying and communicating with personnel directly or peripherally in-
volved in pest management. The monitoring system provides the informa-
tion necessary to set up a communication and training system for imple-
mentation of intervention strategies to suppress pest populations when
and where necessary.
The research component involves determining what levels of the various
pest populations require treatments ("injury levels"), development of
alternative strategies suitable for use against the various pest pro-
blems that arise, and evaluation of treatments so that a predictive
capacity is developed within the aystea. Every effort is made to deter-
mine the best methods of enhancing the natural biological controls that
are already present in the system. Where the biology of the pest and/or
its natural enemies is inadequately known it may be studied through the
monitoring process already in place through the delivery system as well
as by means of lab cultures and field experiments.
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Education is the key component of the system. The people maintaining
the vegetation or habitats must be trained to recognize the natural
enemies of the pests, make counts upon which timing and site selection
of treatments can occur and incorporate alternative pest management stra-
tegies into their ongoing programs. The general public must also be
educated since it is frequently their aesthetic value judgements or
ignorance that triggers pest management actions.
SEQUENCE FOR ESTABLISHING AN IPM PBDGKAM
During the first year in a nev; system the monitoring process is initiated
to determine which are actual pest problems and which are triggered by
previous pest or other horticultural management techniques. A history
of treatments and an inside picture of the bureaucracy involved is obtained.
Problems are rated as to their severity, and a priority list for focus-
ing efforts is agreed upon by all involved. Usually specific areas of
low visibility, whore pest damage can be tolerated, are set aside to
help in determing injury levels and presence of biological control agents.
The educations.1 program is initiated through a system of regular reports
to personnel involved in immediate and supervisory management activities.
Perhaps, most important, the geographic, biological and bureaucratic
boundary of the IPM program is decided upon during this first season.
It is essential that this boundary be set to encompass a large enough
area to permit the solution of the problems included in the system. What
is being done in one area may affect problems in another. For example,
turf management may affect the surrounding trees, the way one species of
shade tree is treated may affect peat management upon other tree species
in the city, students handling of snacks and organic wastes in a class-
room may affect the cockroach problem in the area, etc.
We began working with the city of Berkeley on a classical biological
control project against the linden aphid (EucallipteruB tiliae) under
the auspices of the Division of Biological Control, University of California,
Berkeley. The city had requested control of that problem specifically
and we proceeded, in the usual manner of university researchers attempt-
ing biological control in an orchard or alfalfa field, to focus solely
on the importation of a specific parasite (Trioxys eurvicaudus). After
nearly losing study sites through pesticide treatments of adjacent and
different vegetation we began to perceive that the city-maintained
trees were a system both bureaucractically and biologically. Predators
of insects moved from tree to tree just as city tree maintenance crews
do. By drawing the boundaries of the project large enough to encompass
the management of all the trees in the city we were able to successfully
colonize and spread the natural enemy of the aphid with consequent per-
manent solution co that particular problem. In addition, the satisfactory
development of management strategies for a whole series of other problems
was thereby also obtained. The result was the eventual substantial
reductions in pesticide use throughout the city.
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Because of the vagaries of weather, and variation in other maintenance
practices, it usually takes at least two seasons and sometimes a third
(for example, when two dry years are followed by a wet one as recently
happened in, California) to establish injury levels with any certainty.
During the second and third years, alternative strategies that have proven
effective in sample areas are adapted to larger portions of the system
that include significant variations of microclimate, soils, habitat or
human use, etc.
When the various major pest problems of significance in the system are
examined, one or more may be found to be caused by an insect invader
that has left its natural enemies behind in its area of origin. If no
practical alternative strategies to pesticide treatments can be found
to suppress the populations of the invaded insect the feasibility of
importing its natural enemies should be examined (10). The authors have
employed this technique successfully using host-specific parasites of
various aphids. This strategy offers the potential of an important
partial or total solution to particular problems (12). Another biological
control approach may involve the use of insect diseases, such as
Bacillus tkuringiens-is (BiotrolR, Dipel, ThuricideR) which is specific
against certain caterpillars and does not disturb the beneficial insects.
It should be stressed, however, that some natural biological control
occurrs all the time, even in an area heavily treated with pesticides
or in a well-kept indoor environment (for example, we have found para-
sites on cockroaches inside school buildings). The reason that humand
are able to survive on this planet and grow any plants at all is because
most insect species are under good natural biological control by pre-
dators, parasites and disease. Insect populations that cause problems
are those that for one reason or another are inadequately suppressed by
the natural controls under present conditions. The statement that IPM
means "the integration of cultural, biological and chemical control
methods" has thus confused some people into assuming the biological con-
trol component must mean starting a classical importation project. In
fact, the primary efforts of an IPM program are directed towards the pre-
servation and enhancement of whatever biological controls may already
be operating in the system. This is why a careful monitoring process
is so important.
During subsequent seasons major efforts are made to transfer the technology
to the maintenance people in the system. A predictive capacity should be
in place to aid in increasing efficiencies of labor and materials use.
With reasonable certainty regarding the reliability of various manage-
ment strategies, a vigorous public education effort also can be made.
To someone encountering the idea of an IPM program for the first time,
the complexity of the decision-making process, skills required to adapt
new methods or integrate them into former approaches, and the length of
time needed to establish an ongoing program, may make undertaking the
effort seem prohibitive. In fact, it appears to us that n'" most urban
systems it will take a trained IPM consultant several seasons to establish
. a workable program. Furthermore, the first program in a bio-region
may need support for applied research beyond the financial means of the
cities involved. In addition to direct support from the cities and a
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school district, our pioneering work is also currently funded by the
Environmental Protection Agency and the State Department of Water Resources
and Food and Agriculture. However, it is our experience that once the
program has been developed the technology can easily be transferred over
to the city or institution for which it was developed. The process for
doing so can be designed into the system from the start.
In the final analysis, the adoption of such urban IPM programs will de-
pend on several factors: the public's increasing awareness of the long-
term health and environmental hazards from pesticide use, the perception
by various institutions of the increasing costs and restrictions on the
employment of these materials, and the realization on the part of the
policy makers that viable options already exist (13).
DISCUSSION
QUESTION: Are birds considered a part of the natural predator complex?
ANSWER: There are, of course, many insectivorous birds in urban areas.
I think the important thing to understand is that as you reduce pesticide
use you allow more of the natural controls like birds and smaller predators
to survive. Any program that is able to reduce pesticide use allows for
more natural controls to operate, lou are using the ones that are already
there. You don't have to pay them, they work on weekends and when you
are back in the office. To use all the natural controls available is
one of the major aims of a good integrated pest management program.
QUESTION: As you are evaluating the parasites and predators that are to
be imported from foreign countries are you also evaluating their potential
interactions with the environment?
ANSWER: Absolutely. Let me provide an example: there are about 6,000
species of aphids in the world. Taxonomists break it into about 13 tribes.
'Jhen we look at natural enemies of these aphids, there are not only natural
enemies that attack only aphids but some that are specific to certain
genera of aphids. There are natural enemies that will attack only one
species and not its close relative. I don't want the polyphagous species
(that attack a broad range of hosts) because they are opportunists - they
go where the food is. I want the specific parasites because they will
best regulate a pest population. Specific parasites will not get in-
volved with other components of the system. It is extremely complicated,
like a metabolic fit between two compounds. It is not comparable to
introducing starlings or even ladybird beetles. Also there are strict
quarantine procedures that must be followed.
QUESTION: Hew economical is your shade tree program?
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ANSWEB: The city of Berkeley estimated that we save them $22,500
in 1972. City governments don't fire anybody, they just.rellooate labor.
Most of the cost of treating in aities involves labor; pesticides are
a small cost. The savings were arrived at by taking treatment costs
per tree and multiplying it by the number of trees that they didn't
have to treat after our program started. If you combine the total
number of trees from our other city programs in California the total
savings approached $200'.,000. Our program saves them a small amount
of money even when consultants are included. What is not economical
for them is to pay for the cost of the initial research and development
of an'IPM program. That is why we get EPA and state help. We set up a
model program in a particular region, then your private consultant can
pick up that information and start using it in other cities that have
similar kinds of problems.
QUESTION; How do you see your urban program affecting the agricultural
community?
ANSWER': We see our efforts in urban areas as a flanking movement
to affect policy makers and the general public. 73.5% of the people
in the U.S. live in urban areas according to Bureau of Census infor-
mation. We have some indications that this information has gone over
to the agricultural sector. This is one of our tactics and I can see
it starting to work.
Note: The following references are cited for the purpose of providing
the reader with additional information regarding points mentioned in
this paper.
1. Olkowski, W., D. Pinnock, W. Toney, G. Mosher, W. Neasbitt, R. van
den Bosch, and H. Olkowski, 1974. A Model Integrated Control
Program for Street Trees. Calif. Agr. 28(1):3-4.
2. Olkowski, W. et al. 1978. Urban Integrated Peat Management, In;
Pest Control Strategies. E. Smith, D. Piraentel (Eds.). Academic
Press.
3. .Olkowski, H., W. Olkowski, K. Davis, L. Laub. 1978. Developing an
Integrated Pest Management Program for a School District. Proceedings
of the XII Annual Conference of the Association of Applied Insect
Ecologists, Newport Beach, California.
4. Olkowski, W. and H. Olkowski. 1975. The City People's Book of
Raising Food. Rodale Presa, Emsnaus, Penn. 228 p.
5. Olkowski, H., W. Olkowski. 1975. The Integral Urban House,
to be published Autumn , 1978.
6. Olkowski, W. and H. Olkowski, 1977. Developing Urban I?M Delivery
Systems. Paper delivered at IBM Conference: New Frontiers in Pest
Management, Sacramento, California. Proceedings to be published.
7. Olkowski, H. and W. Olkowski. Sept'. 1976. Entomophobia in the
Urban Ecosystem. Bull. Entomol. Soc. Amer. 22(3):313-317.
-------
8. Olkowski, W., H. Olkowski, R. van den Bosch and R. Horn. 1976.
Ecosystem Management: A Framework for Urban Pest Management.
Bioaoience 26(6):384-389.
9. Olkowski, W. 1973. A Model Ecosystem Management Program. Proc.
Tall Timbers Conf. Ecol. Anim. Control Habitat Manage. 5:103-117.
10. Olkowski, W., H. Olkowski, A. Kaplan, R. van den Bosch. 1978.
The Potential for Biological Control in Urban Areas: Shade Tree
Insect Pests, In; Perspectives in Urban Entomology. J.W. Frankie
and C.S. Koehler (Eds.). Academic Press.
11. Olkowski, W., and H. Olkowski. 1976. Integrated Pest Management
for City Trees. Proceedings of the Midwestern Chapter of the
International Society of Arboriculture. Pp. 21-31.
12. U.S. Department of Agriculture. 1978. Biological Agents for
Pest Control: Status and Prospects. U.S. Dept. of Agriculture
and the Agricultural Research Institute. 138 pp.
13. Olkowski, H. and W. Olkowski. 1978. Some Advantages of Urban
Pest Management Programs and Barriers to Their Adoption.
Proc. of the IPM Seminar presented by the University of California
Cooperative Extension Service in cooperation with the L.A. Commissioner's
Office and the Southern California Turfgrass Council.
127
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128
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CURRENT AND FUTURE RESEARCH NEEDS
Kenneth J. Hood
Office of Research & Development
Environmental Protection Agency
Washington, D.C.
rNTRDDUCTION
I would like to compliment Pieter de Jong and the Wright-Ingraham
Institute for the work which has gone into this well organized confer-
ence. The program has moved along nicely and I think we all owe a debt
of thanks to Pieter and the stalwart crew which has assisted him.
I am in the Office of Research and Development at the Environmental
Protection Agency and I was asked to talk on the.current and future
IPM research needs. With a topic which looks into the future, my jreatest
need is for a fortune teller's clear crystal ball. I could not find
one to borrow. Nevertheless, I shall give you some thoughts I have
been gathering over the last several days on what I think we are going
to eventually need in IPM research.
Integrated Pest Management is comparatively new on the government scene,
as far as EPA is concerned. We believe there are both rural and urban
IPM needs. For the immediate future in agriculture, I do not believe
the direction of present research is going to significantly change from
what we are now pursuing. Our major emphasis now is on insect control
but there is beginning to be a gradual awareness of a need to investigate
plant or weed control, which I will discuss a little later.
INSECT CONTROL
Regarding insect control research, I believe that in the future,
it will be necessary to know much more about many of our important insect
pests. When we examine what is now being done in any crop system, we
often find most of the work is concentrated on an intensive study of
just a few of the problem insects. I believe we will see an expansion
of study into more species.
Thare will be an expansion of work into insect population dynamics
of our worst pest species and their interactions with others. It will
be necessary to have more biological information on how insects live and
the effects of the environment upon them because they are very adaptive
129
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to adversity, The gene pool with which we are dealing has sufficient
resiliency that it has survived thousands of years. Mankind's pest
management efforts represent just another stress for it. We are going
to have to do more research on the crop-pest interactions. Oftentimes
the entomologists or the agronomists follow their own narrow speciality
and do not talk together and compare notes. We will find increasing
need to bring the disciplines closer together.
WEED CONIK3L
Plant control is an old subject that is again being noticed. We have
heard discussions about no-till and reduced-till culture, the use of
herbicides, and so forth. We are still heavily dependent on chemical
control. There is a lot being done in cultural weed control but if
energy supplies become a problem, tractors cannot be run as often as
needed and the farm community is going to ask "What are our options?
What else can we do?" This situation will bring to the forefront the
need for non-chemical weed control which might include utilizing pathogens
and predators. These are comparatively unexplored fields and there are
not many researchers working full time in these areas.
We need a lot of information on field ecology dealing with interactions
between useful and non-useful plants; that is, crops and weeds. Why
are weeds so competitive? There are many reasons and I believe that we
often do not fully explore the underlying basic botany of the plants to
reveal how they thrive in the field. Presently, EPA is supporting a
program on musk thistle control. For that program it was apparent that
we did not have sufficient knowledge about the botany of the plant. We
hope that such information will reveal weaknesses in'the life cycle which
can be exploited to permit better control.
URBAN IHl
Let us shift now from the rural to the urban IPM scene. I believe
that urban IPM is here to stay. The phrase "urban IPM" has only
recently come into use but for some scientists, it's a familiar field
because they have been working in it for a long time. I divided this
topic into two areas: inside and outside the home. Within the home
one finds the control of cockroaches as a major focus. But controls can
cover just about anything that crawls into or lives within the home.
The homeowner often gets upset about insect problems. If he can
rid his residence of insects; he may often tolerate insects outside his
garden. On the other hand, there are many people who do not want to
see a single aphid anyplace in their garden. Furthermore, they will
use an immense amount of chemicals to make their garden insect free.
Therefore, I think we are going to need more work on control of insect
pests in lawns and gardens. One can extend this topic to other urban
situations such as publicly maintained street right-of-ways and parks
130
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where tailor-made urban IPM practices will be useful. It is un-
fortunate that the number of scientists working in this area is small.
Progress will be slow.
FUTURE RESEARCH NEEDS
Let us consider some other future IPM frontiers. While predictions
are always lacking in accuracy, I would say the following are likely
to occur. I think that the ability of man to culture large numbers of
desirable predators is going to be an area of fruitful research. It
would be highly desirable if we could have the ability to readily
utilize inundative predatory insect releases under certain situations
to control damaging insect outbreaks. This might reduce the need to
establish predator populations which must survive the winter or some
other environmental stress. Would it not be helpful if we could just
order, as one of the speakers said, five gallons of some control insect;
release them and know that they would survive long enough to take care
of a particularly bad situation?
I think that there will be a continuing effort to find and utilize
fungal, bacterial, and viral pathogens for insect control and especially
for biotic control of weeds. Regretfully, this is another area which
does not have enough people working in it. That does not, nevertheless,
reduce the need.
Now I wish to discuss something which I think is a very basic approach
to insect control and which will perhaps receive the most attention in
the future. I refer to biochemical regulation of our pest populations.
That is, the use of various insect and plant growth regulators to
control unwanted pests. In order to utilize these techniques we need
to have a greater physiological understanding of the control mechanisms
of undesirable pest insects and weeds. If one considers that all living
entities are composed of chemical compounds, it follows that one should
eventually be able to unravel the mystery enough to attain control.
This is not an easily accomplished goal. Some of the molecules, infor-
mation molecules, are transient and fragile; they come into being.
react, and are gone, leaving almost no way of identifying them. Never-
theless, the insects respond to them. The insect: can tell when they are
on an alfalfa plant; they can discriminate types of food; they can
disciminate hostile and acceptable environments where they can live;
they can identify and find mates for reproduction. These and other re-
sponses are chemically controlled within the physiology of the pest. If
we consider what we know versus what is obviously taking place in nature,
it's not difficult to deduce that there remains a great deal we do not
yet understand.
It has been pointed out that we know very little about the chemistry that
controls plant resistance to insects. Sometimes the mechanisms are
quite unusual. We heard today at this meeting that in one situation
varying plant susceptibility to insect attack was simply due to greater
131
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or lesser amounts of silicon in the plant cells. In those plants with
high silicon, the mandibles of the insects were worn down causing
the insects to starve. This is an amazing revelation. How many plant
breeders have considered a pest control mechanism involving an increase
in the silicon content of the plant cell in order to protect the crop?
If we knew in greater detail what was needed it might drastically
change how plant breeding programs are designed.
Consider for instance how weeds compete and invade into new areas.
It may be their growth habit, or it just may be a chemical predisposition
orchestrated by the presence of the plant.
We really do not sufficiently understand many things about ecological
succession. If we knew more clearly the events taking place we might
be able to use that information in agricultural ecosystems. In fact
if we used a holistic approach such as ecologists often use we may very
well be farther ahead than with our fragmented approach now being used.
My last observation builds somewhat upon all my previous ones. Basically
a case has been made for the need for more information about pests and
how they function. How the data (information) should be handled is
the last point I wish to discuss. Succinctly stated, I believe the most
efficient and long lasting way to use the data is to incorporate it,
whenever possible, into mathmatical models which can be revised and im-
proved as more facts are revealed. Models will survive long after the
investigator has moved to other interests. Subsequent additions by
others will make such models good cumulative distillations of the
important aspects of pest organisms, their responses to each other
and to other biological entities and to the various environments in
which they live. With the availability of these increasingly accurate
mathematical models, the control of pests will become more attainable
because we will be able to readily discern the achievable from the
unachievable.
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THURSDAY, 30 MARCH
FRIDAY, 31 MARCH
3:30 am Registration
9:15 am Introduction
Elizabeth Wright Ingraham, President,
Wright-1ngraham Institute
James Lehr, Environmental Protection Agency
Region VIII
Introduction to morning speakers: Robert Simpson,
Colorado State University
9:30 am
CURRENT PRACTICES IN INSECT PEST CONTROL
David Pimentel, Cornell University
10:20 am
BIOLOGICAL CONTROL BY USE OF NATURAL
ENEMIES
Robert van den Bosch, University of California
11:10 am
CULTURAL METHODS FOR PEST CONTROL
Theo F. Watson, University of Arizona
12:00 Lunch
1:00 pm
Working Sessions: PEST PROBLEMS FACING THE
REGION
CROP PESTS (Rm. C)
Eugene Heikes, Extension Professor, Colorado
State University
William Hantsbarger. Extension Professor,
Colorado State University
FOREST PEST MANAGEMENT (Hort. Hall)
Robert Stevens, Rocky Mtn. Forest & Range Exp,
Stat., USFS
Kenneth Lister, Forest Pest Management, USFS
Dave Leatherman, Colorado State Forest Service
LIVESTOCK AND RANGE PESTS (Rm. B)
Austin Haws, Utah State University
Lowell McEwen, Fish & Wildlife Service
URBAN AND HORTICULTURE PESTS (Rm. A)
Byron Reid, Past Control Association, Regional
Chapter
John Qum, Colorado State University
3: I'o p;n — - .
Plenary Session: summary of working sessions
4:15 pm
EP,\ AND PEST MANAGEMENT Charles Rees
Otfica of Pesticide Programs, Environmental
Protection Agency, Washington, D.C.
4:50pm Adjourn
Introduction to Morning Speakers, Beatrice Willard,
Colorado School of Mines
9:00 am
USDA AND PEST MANAGEMENT, Richard L
Ridgway, Staff Scientist. Science Education
Administration, Beltsville, Maryland
9:35 am
ECONOMICS OF PEST MANAGEMENT, Raymond
Frisbie, Cooperative Extension Service, Texas A&M
10:10 am
Panel Discussion: IMPLEMENTATION OF
INTEGRATED PEST MANAGEMENT
PROGRAMS. Panel Leader: Leon Moore,
Cooperative Extension Service, University of
Arizona
William Olkowski, Univ. of California
Mesa County Peach Administrative Committee,
Wayne Bain; Allan Jones; Palisades, Colorado
Earlie Thomas, Field & Lab, Inc., Ft. Collins
12:00 Lunch
1:00 pm
Panel Discussion: VIEWS ON PEST MANAGEMENT
Panel Leader: F. Martin Brown,-. Wright-lngraham
Institute
Thomas Lasater, Rancher, Matheson, Colorado
Glen Murray, Farmer, Brighton, Colorado
William Tweedy, Cebi-Geigy, Inc.; North Carolina
Pauline Plaza, Audubon Society, Lakewood,
Colorado
2:30 pm
Working Sessions: CASE STUDIES ON
INTEGRATED PEST MANAGEMENT
PROGRAMS
ALFALFA, Donald W. Davis, Utah State Uni-
versity
Robert Simpson, Colorado State University
URBAN PEST MANAGEMENT, William and Helga
Olkowski, University of California and John Muir
Institute
BREEDING INSECT RESISTANCE IN PLANTS:
WHEAT AND ^HESSIAN FLY, Robert Gallun.
Science Education Administration (USDA)
Purdue University
THIRD GENERATION PESTICIDES: PHERO-
MONES AND HORMONES,' E. Mitchell, Science
Education Administration, Gainsville, Florida
4:00 pm
Plenary Session: CURRENT AND FUTURE RE-
SEARCH NEEDS, Kenneth Hood, Environmental
Protection Agency, Research & Development,
Washington, D.C.
4:40 pm Adjourn
133
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134
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CONFERENCE PARTICIPANTS
DR. DAVID AKEY, USDA, FR-SEA, Arthropod-borne Aniraal Disease Research
Lab, Denver, Colorado.
JANET ALBRIGHT, Colorado State University, Ft. Collins, Colorado
DEBRA ALLEN, student, Colorado State University,, Ft, Collins,
Colorado
ROBERT ANDERSON, Denver Housing Authority, Denver, Colorado
WAYNE BAIN, Executive Secretary, Mesa County Peach Administrative
Committee, Palisade, Colorado
CAROL BARBER, Aurora Vo-Tech, Aurora, Colorado
DR. A. H. BAUMHOVER, USDA, FR-SEA, Tobacco Research Lab, Oxford, North
Carolina
DR. MICHEAL BREED, EPO Biology, University of Colorado, Boulder, Colorado
FRANCO BERNARKI, Manager, Superior Farming Company, Tucson, Arizona
F. MARTIN BROWN, Staff Naturalist, Wright-Ingraham Institute, Colorado
Springs, Colorado
HERB CHILDRESS, Master Gardener, Colorado Springs, Colorado
WAYNE COLBERG, Cooperative Extension Service, North Dakota State University,
Fargo, North Dakota
PHYLLIS CORCHARY, Cooperative Extension Service, Jefferson County, Colorado
DR. DONALD DAVIS, Utah State University, Logan, Utah
PIETER DE JONG, Administrative Staff, Wrlght-Ingraham Institute, Colorado
Springs, Colorado
STEVE DENNIS, Steams-Rogers Inc., Aurora, Colorado
LAWRENCE R. DE WEESE, U.S. Fish & Wildlife Service, Fort Collins, Colorado
CAROLINE DE WILDE, Cooperative Extension Set-vice, El Paso County, Colorado
Springs, Colorado
DOROTHY DICKERSON, Horticultural Advisory Council, Colorado Springs,
Colorado
DENNIS DOWNING, teacher, Aurora Vo-Tech, Aurora, Colorado
DR. KENNETH DOXTADER, Horticulture Dept., Colorado State University, Ft.
Collins, Colorado
LESLIE EKLUND, IPM consultant, Western Field Technology, Palisade, Colorado
DR. H. E. EVANS, Dept. Zoology and Entomology, Colorado State University
Ft. Collins, Colorado
DOROTHY FALKENBERG, Cooperative Extension Service, Golden, Colorado
CATHRYN FLANAGAN, student, Colorado State University, Ft. Collins, Colorado
KENNETH FORDYCE, Denver Housing Authority, Denver, Colorado
CAROLE FORSYTH, Denver Audubon Society, Northglenn, Colorado
J. H. FOWLER, Chairman, Biocides Recyling Committee, Enos Mills Group of
Che Sierra Club, Denver, Colorado
DR. RAYMOND FRISBIE, Texas Cooperative Extension Service, Texas A&M,
College Station, Texas
DR. ROBERT L. GALLUN, USDA, FR-SEA, Purdue University, West Lafayette
Indianna
KEITH E. GOOSMAN, teacher, Pouder School District, Ft. Collins, Colorado
W. L. GORDON, Colorado Agricultural Chemicals Association, Denver,
Colorado
LYNNE GRACE, Aiken Audubon Society, Colorado Springs, Colorado
135
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DR. WILLIAM HANTSBARGER, Extension Professor, Department of Zoology and
Entomology, Colorado State University, Ft. Collins, Colorado
RICHARD HART, Northwest Missouri State University, Maryville, Missouri
DR. AUSTIN HAWS, Biology Department, Utah State University, Logan, Utah
EUGENE HEIKES, Extension Professor, Weed Research Lab, Colorado State
University, Ft. Collins, Colorado
DR. KENNETH HOOD, Office of Research and Development, Environmental
Protection Agency, Washington, D.C.
CAROLYN HUISJEN, LCTC Horticulture Society, Ft. Collins, Colorado
BARBARA HYDE, Cooperative Extension Service, Boulder County, Colorado
ELIZABETH WRIGHT INGRAHAM, President, Wright-Ingraham Institute, Colorado
Springs, Colorado
DR. ROBERT H. JONES, Research Entomologist, USDA, FR-SEA, Denver,
Colorado
DR. JAY B. KARREN, Extension Entomologist, Utah State University,
Logan, Utah
LEWIS KEENAN, USDA, APHIS, Denver, Colorado
RICHARD KEIGLEY, National Park Service, Denver, Colorado
EDWARD KEITH, Biology Department, University of California at Santa Cruz,
Santa Cruz, California
JAMES KEITH, U.S. Fish & Wildlife Service, Patuxent Wildlife Research
Center, Denver, Colorado
DAVID N. KIMBALL, Denver, Colorado
THOMAS LASATER, The Lasater Ranch, Matheson, Colorado
MARIE LAUFER, student, University of Colorado, Colorado Springs, Colorado
DAVID LEATHERMAN, Colorado State Forest Service, Ft. Collins, Colorado
JAMES LEHR, Hazardous Waste-Division, Environmental Protection Agency,
Region VIII, Denver, Colorado
KENDALL LISTER, Forest Pest Management, Rocky Mountain Region, U.S Forest
Service, Denver, Colorado
JEANNE MALONEY, Horticultural Advisory Council, Colorado Springs,
Colorado
JOHN B. MC CLAVE, Cooperative Extension Service, Summit County, Frisco,
Colorado
LOWELL C. MCEWEN, U.S. Fish & Wildlife Service, Patuxent Wildlife
Research Center, Ft. Collins, Colorado
DALLAS MILLER, Pesticide Branch, Environmental Protection Agency,
Region VIII, Denver, Colorado
DR. J. MINTON, EPO Biology, University of Colorado, Boulder, Colorado
DR. EVERETT R. MITCHELL, USDA, FR-SEA, Insect Attractants Laboratory,
Gainesville, Florida
DR. LEON MOORE, Cooperative Extension Service, University of Arizona,
Tucson, Arizona
RONALD MORROW, City Park and Recreation Department, Colorado Springs,
Colorado
DONALD NELSON, Boulder, Colorado
EUGENE NELSON, Cooperative Extension Service, Alamosa County, Alamosa,
Colorado
.LYNDA M. NIELSEN, Loveland, Colorado
DR. WILLIAM OLKOWSKI, Center for' the Integration of the Applied Sciences,
John Muir Institute, Berkeley, California
136
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HELGA OLKOWSKI, Center for the Integration of the Applied Sciences,
John Muir Institute, Berkeley, California
TIM ORTNER,'Representative for President of the Colorado State Senate,
FRED ANDERSON, Denver, Colorado
ANDREW PIERCE, Superintendent of Conservatory, Denver Botanic Gardens,
Denver, Colorado
DR.. DAVID PIMENTEL, Department of Entomology, Cornell University,
Ithaca, New York
PAULINE PLAZA, Western Environmental Science Program, National Audubon
Society, Lakewood, Colorado
JOHN POHLY, Larimer County Vo-Tech, Fort Collins, Colorado
DR. JOHN A. QUIST, Department "of Zoology and Entomology, Colorado State
University, Ft. Collins, Colorado
CHARLES REESE, Office of Pesticide Programs, Environmental Protection
Agency, Washington, D.C.
STUART REEVE, Ft. Collins, Colorado
BYRON REID, Regional Vice President, Pest Control Association, Colorado
Springs, Colorado
RICHARD RIDGWAY, National Program Staff, Federal Research, Science and
Education Administration, USDA, Beltsville, Maryland
KEVIN ROSENFOFFER, student, Colorado State University, Ft. Collins,
Colorado
ALEX SCHUETTENBERG, Ft. Collins, Colorado
J. F. SHAUGHNESSY, Monte Vista, Colorado
DANIEL SHEEHY, Stillpoint Hermitage, Manitou Springs, Colorado
FRANK SIEBURTH, Castle Rock, Colorado
MARGRET SIKES, Denver Botanic Gardens, Denver, Colorado
JOAN E. SIKKENS, Denver Audubon Society, Aurora, Colorado
DR. ROBERT SIMPSON, Department of Zoology and Entomology, Colorado State
University, Ft. Collins, Colorado
RONALD STEE, South Dakota Department of Agriculture, Pierre, South Dakota
BARBARA STEINMEYER, Department of Parks & Recreation, City of Westminster,
Westminster, Colorado
DR. ROBERT STEVENS, Rocky Mountain Forest and Range Experiment Station,
U.S. Forest Service, USDA, Ft. Collins, Colorado
ADAIR STONER, USDA, FR-SEA, Honey Bee, Pesticides & Diseases Research,
University Station, Laramie, Wyoming
CURT SWIFT, Cooperative Extension Service, El Paso County, Colorado Springs
Colorado
JERROLD SWITZER, Department of Parks & Recreation, Colorado Springs, Colorado
EARLIE THOMAS, President, Field & Lab, Inc., Ft. Collins, Colorado
DR. ROBERT VAN DEN BOSCH, Division of Biological Control, University of
California at Berkeley, Berkeley, California
MARK WALMSLEY, Dept. of Zoology and Entomology, Colorado State University,
Ft. Collins, Colorado
JUDY WARD, Denver Audubon Society, Denver, Colorado
DR. THEO WATSON, Department of Entomology, University of Arizona, Tucson,
Arizona
T.OI.S WEBSTER, Aurora, Colorado
WAYNE WEHLING, Arvada, Colorado
DR. BEATRICE WILLARD, Environmental Sciences, Colorado School of Mines,
Golden, Colorado
137
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BRUCE WILLIAMS, Superior Farming Company, Tucson. Arizona
PANDORA WILSON, Master Gardener, Jefferson County Extension, Lakewood,
Colorado
MEREL 0. WOODS, Cooperative Extension Service, Arapahoe County,
Littleton, Colorado
DAVE WOODWARD, Broadmoor Greenhouse, Colorado Springs, Colorado
MICHEAL WYBLE, Department of Parks & Recreation, City of Westminster,
Colorado
138
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INDEX
Acryrthosiphum pisum, 3, 63
agrichemical industry, view on IPM, 94
agroecosystem, 93,100
diversification of, 60
AID (Agency for International
Development),
role in IPM, 112
alfalfa,
ecosystem model for, 41
harvesting dates, 62
IPM in, 40-42
pests, 42
resistant varieties, 3, 40
strip-cutting of, 62
aphid,
linden, 123
pea, 3, 63
spotted alfalfa, 65
Aphidus smith!, 38
atmospheric permeation, 71
B
Bacillus thurlngiensis, 22, 124
beetle,
ambrosia, 76
mountain pine bark, 25-27
biological control,
classic introduction programs, 7, 52,
124
definition of, 49
host specificity of control agent,
52-53, 125
in alfalfa, 37-39
In peach orchards, 37
naturally occurring, 54-55, 124
of klamath weed, 38
regional programs, 37-39
weeds, 52-54
biotype, 83
Blissus leucopterus, 3
bollworm, pink, 66-69, 71-72
additive cultural practices on, 65-67
budworm, eaatorn spruce, 75
CEQ (Council on Environmental Quality),
112
chemical sex attreactants, 8*10
chinch bug, 3
codling moth, 74
Colorado Department of Agriculture,
biological control programs, 36-38
seed embargoes, 23
Commonwealth Institute of Biological
Control, 53
corn,
earworm, 73
insect control in, 22
leaf blight, southern, 5,13
rootworm, 4, 22, 61
cotton,
control of lygus in, 62-63
cultural controls in, 4
early IPM program, 99
reduction of insecticide use in,
102-103, 106-107
scouting program in, 101-102
crop,
breeding insect resistance in,
2, 81-85
effects of reduced genetic diversity
in, 5
losses to pests, 1
losses, postharvest, 1
insect resistant varieties, 2-3
rotations, 4, 61
cultural control,
attributes of, 60
cropping systems, 4-5
definition of, 59
goals of, 60
In cotton, 66-69
planting dates, 6-7, 61
strip cutting systems, 62-63
trap crops, 64
Delaney Clause, 110
Dendrosoter protuberans, 38
139
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diapause, 67
Diparopsis castanoa, 72-73
HUD (Housing & Urban Development),
role in IPM, 112-113
economics,
In chemical weed control, 23
In urban shade tree IPM, 126
of pest management in cotton,
105-107
economic thresholds, 23, 93,105
economic poison, 109 (see also pesticide)
ecosystem, effects of pesticides to,
12-13, 31-32
Endrln, 23
EPA (Environmental Protection Agency),
regulatory responsibilities for
pesticides, 111
role in implementing IPM, 113
field bindweed, 23
F1FHA (Federal Insecticide, Fungicide, &
Rodentlclde Act), 109
forest, pest management, 25-27
G
gossyplure, 72 (see also pheromone)
government, policies on range manage-
ment, 43, 45
grasshopper, control in range, 24*25
grower organizations,
cotton, 101-103
orchards, 35-36
gypsy moth, 8
I
injury levels, 122 (see a/so economic
threshold) _
Insecticide (see also pesticide)
aldrln, 24
malathion, 24
reduction in shade trees, 123
reduction of use in cotton, 102-103,
106-107
Integrated pest control, 91 (see also
integrated pest management)
integrated pest management (IPM)
consultants, 36,124
definition of, r, 59, 91
future research needs, 129-132
implementation of, 118-119
in alfalfa, 40-42
In cotton, 65-69, 101-103, 105-107
In home gardens, 120,121
in orchards, 36
In pine bark beetle control, 25-27
research needs in range, 43-45
urban, 121-124
urban research needs, 130
Inter-agency Regulatory Liaison Group, 35
interdisciplinary research in range, 44-45
Labops sp., 44
labor, in agriculture, 29, 92
Lygus sp.. 95
effects of stripcutting on, 4, 62
H
habitat management, 26, 59
herbicides, (ss« also pesticide)
effects on insect populations, 13,
regional use of 23-24
use of 2, 4-p in weed control, 23
Hessian fly, 3, 81-83
fly free planting dates, 61-62
genetic control of, 85
HEW (Health, Education & Welfare),
role in IPM, 112
host specificity of parasites, 52-53, 125
M
Macrocentrua ancylivorua, 36-37
Meyatloia (Instructor, 3, 61-62, 81
mediterranean fruit fly, 8
Millar Admendment, 110
mite,
Bank's grass, 22
two spotted, 37-38
modelling,
crop management systems, 132
in alfalfa, 91-92
multlcrcp approach, 102
140
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N
National Academy of Sciences (NAS), 113
National Agricultural Chemicals
Association (NACA), 92, 94
NSF (National Science Foundation),
support of IPM, 113
Neosema locustae, 23-24
olfactory attractants, 7-10 (see also
semiochemicals, pheromones)
organophosphates, 99-100
redbanded leaf-roller, 3
rootworm, see corn, rootworm
saltmarsh caterpillar, 63-64
sand wireworm, 64
semio-chemicals, 72
sorghum,
resistant varieties, 3
cultural controls in, 62
soybeans, 4
parasite, definition of, 49
parasltold, definition of, 49
pathogen, definition of, 49
pesticides,
benefits, 9-11,91-92
carbamates, 99
development of resistance In insects,
100
distribution of use, 10
effects on crop physiology, 13
effects on non-target species, 23
effects on public health, 12
effects on raptor populations, 32
environmental costs, 11-12, 31-33
residues in produce, 12
pest management (see also IPM),
basic elements of, 100-101
components of, 99
definition of, 1
economics of, 105-107
in forests, 25-27
of cotton, 101-103
systems, 93
use of pesticides In, 94
use of resistant varieties in, 81
pheromones,
atmospheric permeation, 71
dosage response, 10
for population sampling, 75-76
potential In pest management, 7-10,
71-74
sex attractants, 71-73
use in stored products, 74
Porthetria dispar, 8
predator, definition of, 49
technology transfer,
rural to urban, 122-124
to home gardens, 120
Texas Cotton Pest Management Program,
107
thistle,
bull, 23
Scott's, 23
musk, 23, 38, 130
trap crops, 64
Trloxys curuicandus, 23
tussock moth, 56, 75
Typhloromus occidentals, 37
U
USOA,
early IPM projects, 82, 117-118
mission, 177
role in implementing IPM, 118-119
w ;--:
water management, 65
weed,
biological control of, 52-54
contemporary control strategy,
23-24
control districts, 24
weevil, alfalfa, 40-42 62 (see a/so alfalfa)
wheat, 23
use of resistant varieties, 82-35
141
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