• TABLE OF CONTENTS
HIDE
 Front Cover
 Abstract
 Preface
 Table of Contents
 List of Tables
 List of Figures
 The research question and the historical...
 Area studied
 The empirical model
 Empirical results of the demand...
 Application of agricultural pesticides...
 Pesticides and externalities
 Analytical results and implica...
 Further conclusions and implic...
 Reference














Title: Social welfare implications of alternative pesticide policies
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Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00049899/00001
 Material Information
Title: Social welfare implications of alternative pesticide policies
Alternate Title: Economic information report - University of Florida Food and Resource Economics Dept. ; 79
Physical Description: Book
Language: English
Creator: Edwards, W. F.
Langham, M.R.
Publisher: Food and Resource Economics Dept., University of Florida
Publication Date: 1976
 Subjects
Spatial Coverage: North America -- United States -- Florida -- Dade
 Record Information
Bibliographic ID: UF00049899
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Table of Contents
    Front Cover
        Front Cover
    Abstract
        Abstract
    Preface
        Page i
        Page ii
    Table of Contents
        Page iii
        Page iv
    List of Tables
        Page v
        Page vi
        Page vii
    List of Figures
        Page viii
    The research question and the historical development of the pesticide issue
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
    Area studied
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
    The empirical model
        Page 23
        Page 24
        Page 25
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
        Page 38
    Empirical results of the demand and supply models
        Page 39
        Page 40
        Page 41
        Page 42
    Application of agricultural pesticides in Dade county
        Page 43
        Page 44
        Page 45
        Page 46
        Page 47
        Page 48
        Page 49
        Page 50
        Page 51
        Page 52
        Page 53
        Page 54
        Page 55
        Page 56
        Page 57
        Page 58
        Page 59
        Page 60
        Page 61
        Page 62
        Page 63
        Page 64
        Page 65
        Page 66
        Page 67
        Page 68
        Page 69
        Page 70
    Pesticides and externalities
        Page 71
        Page 72
        Page 73
        Page 74
        Page 75
        Page 76
        Page 77
        Page 78
        Page 79
        Page 80
        Page 81
        Page 82
        Page 83
        Page 84
        Page 85
        Page 86
        Page 87
        Page 88
        Page 89
        Page 90
        Page 91
        Page 92
        Page 93
        Page 94
        Page 95
        Page 96
    Analytical results and implications
        Page 97
        Page 98
        Page 99
        Page 100
        Page 101
        Page 102
        Page 103
        Page 104
        Page 105
        Page 106
        Page 107
        Page 108
        Page 109
        Page 110
        Page 111
        Page 112
        Page 113
        Page 114
        Page 115
        Page 116
        Page 117
        Page 118
        Page 119
        Page 120
        Page 121
        Page 122
        Page 123
        Page 124
        Page 125
        Page 126
        Page 127
        Page 128
    Further conclusions and implications
        Page 129
        Page 130
        Page 131
        Page 132
        Page 133
        Page 134
    Reference
        Page 135
        Page 136
        Page 137
        Page 138
        Page 139
        Page 140
Full Text
.: 1976-'


Socia


Welfare Implications of-:t
Wf'a- re .1"*-....


Alternative Pesticid

A Case Study of the


Policies:


Agriculture--


of Dade County, Florida


HUME LiBRARY

-. -- .-. A-. 1977
source Economics Department 5.
; Experiment Stations .
of Food and Agricultural Sci,.. Un. O FOrid
--Florida, Gainesville 326 i. or For
--:. Florida,' Gainesville 32o !jte, ...... "


W. F. Edwards
LA I L
tiYi. i1. -


F~"eas a raap~aWr~B~i~s~WPR~BC~~


Economics Report 79


,


-
;;








ABSTRACT


This study was concerned with the economic externalities created by the
use of agricultural pesticides and the implications of such externalities on
C-i welfare. The working hypothesis was that the externalities could be
-.:ed, and the objective was to measure them for some specified region
time period and to incorporate them into a model which was developed to
aid in the choice of a pesticide usage policy for the area. The choice,
criterion was a measure of social welfare.

The model employed the concept of consumers' plus producers' surplus as
a measure of "welfare." For each of three specified policies the model maxi-
--t. this measure of welfare over production alternatives available to the
region. In each case the objective function explicitly recognized-measurable
.* alities not accounted for by.consumers' plus producers' surplus. Finally
,, policies were ranked by their maxima.

It was demonstrated that the model could conceptually accommodate en-
...... mental constraints connecting the levels of pesticide usage with levels
pesticide residues monitored in various elements of the environment,
empirical data to specify such constraints were not available.

Parametric programming was employed on selected parameters of the model
examine the stability of the solution.

The model solutions indicated that, in general, very large changes in
level of externalities caused very small changes in the solution acreages
Sin the objective function. A 50 percent reduction in the per acre usage
chlorinated hydrocarbons caused a 1 to 2 percent reduction in the net
benefits of the crops studies. And, a virtual elimination of chlo-
Sd hydrocarbons resulted in a 3.7 percent reduction.

Adequate data::fora complete benefit-cost analysis of agricultural
ide usage are not yet available, particularly in the area of long-run,
-vel exposure to persistent pesticides. The methodology used in this
ch project is capable of incorporating such data when they become
-ble.

Key words: pesticides, externalities, parametric programming.






W. FRANK EDWARDS is a research economist in the Industrial Research and -
ion Center and Associate Professor of Economics, University of Arkansas.
LANGHAM is professor of ffood and, resource economics,. University of:.















PREFACE


During almost the entire decade of the 1960s there was a great

public concern over the use of pesticides and how they might ultimately

effect ecological balances. Rachel Carson's Silent Spring was a major

impetus for the-congressional hearings from May 1963 to July 1964, and

the most tangible outcome of the public outcry was an eruption of laws,

both federal and state, to control and reduce the more persistent

varieties of pesticides. Simultaneously money flowed into pesticide

research. An appropriation of 29 million dollars was made for such re-

search in the U.S. Department of Agriculture. A program involving the

Departments of Agriculture, Interior, Defense, and Health, Education,

and Welfare was initiated to monitor levels of pesticides in the

environment. .The Federal Committee on Pest Control was formed to coor-

dinate the many pesticide research programs of various government

agencies. During 1970 the Environmental Protection Agency was formed

and has taken over many of the functions relating to the regulation of

the research on pesticides.

The study reported in this monograph traces its origin to the

research program sponsored by Resources for the Future, Inc., during

the 1965-1970 period. The study is an extension and empirical applica-

tion of a theoretical model suggested by Headley and Lewis [24]. It is

oriented toward the identification, measurement, and explicit inclusion

of externalities in evaluating alternative pesticide policies. Most of







the data for the study came from Dade County Florida, an area of inten-

sive agricultural production specializing in the growing of winter

vegetables and fruits for northern markets.

The study was conducted during the period 1967-69 and since that

time some significant changes have taken place in the types and quanti-

ties of pesticides used, in cultivation practices, and in pesticide

regulations. Nevertheless, the methodology presented is generally ap-

plicable to economic policy problems involving externalities.

Throughout the period covered by the project we enjoyed the gener-

ous support of Resources for the Future, Inc. A special word of thanks

is due Allen V. Kneese and Blair Bower for their comments on various

versions of the projects. We are also grateful to the staffs of the

County Agent's office of Dade County for assistance in gathering data

and to the Florida and Missouri Agricultural Experiment Stations for

administrative and financial support.















TABLE OF CONTENTS


Table


PREFACE . . . . .. . .


LIST OF TABLES . . . . . . .


LIST OF FIGURES . . . . . ..


i


iii

viii


I THE RESEARCH QUESTION AND THE HISTORICAL DEVELOPMENT
OF THE PESTICIDE ISSUE . .. . . .. 1

The Research Question .................. 1
Historical Development of the Pesticide Issue ..... .3

II AREA STUDIED . . . .... .... 11

Choice of an Area . . . .... 11
Agriculture of Dade County . . . .. 12

III THE EMPIRICAL MODEL . ... ........ 23

'Mathematical Statement of Model . .. .. . 23
'Estimates of Model Parameters . . ... 26

The Demand Model . . . .. .... 26
The Supply Model . . . .. ... 30
The Externality Function . . ... 33
Constraints on the Objective Function . ... 37

APPENDIX TO CHAPTER 3: EMPIRICAL RESULTS OF THE
DEMfAID AND SUPPLY MODELS . . . ... 39


IV APPLICATION OF AGRICULTURAL PESTICIDES IN DADE
COUNTY . . . . . ...

Technology of Pesticide Application in Dade
County . . . . . .
Estimating the Quantities of Pesticides Used in
Dade County . . ..


S 43


4* *


CHAPTERS


. .






TABLE OF CONTENTS (Continued)


V PESTICIDES AND EXTERNALITIES . .

Externalities in Dade County . .
The Aggregation Problem . .

VI ANALYTICAL RESULTS AND IMPLICATIONS

Policy 1 . . . .
Policy 2 . . . .
Policy 3 . . . .
Environmental Constraints and Wildlife
On Data and Information Needs ..

VII FURTHER CONCLUSIONS AND IMPLICATIONS .

Conclusion . . . .

REFERENCES . . . . .


iv


Table

71

71
91

97

97
99
109
110
124

129

134

135















LIST OF TABLES


Page


Table


Dade County


1 Quantities of insecticides used on crops by farmers
by geographic regions, 1964, 1966, and 1971 . .

2 Agricultural production in Dade County, Florida,
1966-1967 . . . . . .

3 Florida and Dade County population changes from 1950
to 1960 . . . . . .

4 Demand functions used in the model .. . .

5 Supply functions .used in the model . . .

6 Empirically estimated relations from which demand
functions were derived .. .. . . ..

7 Empirically estimated relations from which supply
functions were derived . . . .

8 Alternative recommended insect control measures for
tomatoes . . . . . .

9 Alternative recommended insect control measures for
potatoes .. . . . . .

10 Alternative recommended insect control measures for
beans . . . . . .

11 Alternative recommended insect control-measures for
corn . . . . . . .

12 Alternative recommended insect control measures for
squash . . . . . ...

13 Alternative insect control programs for tomatoes-in
Dade County . . . .

14 Alternative insect control programs for potatoes in


. . . . . . 56


15 Alternative insect control programs for pole beans in
Dade County . . . . .


7
. 7


. 15


. 20

. 31

. 32


. 41


42


. 47


. 48


. 49


. '50


. .51


.. 53








LIST OF TABLES (Continued)


Table Page

16 Alternative insect control programs for sweet corn
in Dade County ... .. . . .. 61

17 Alternative insect control programs for squash in
Dade County . . . . . . 63

18 Estimated average quantities per acre of organic
phosphates, chlorinated hydrocarbons, and total pesti-
cides used by farmers in Dade County, 1966-1967 crop
S year, by crop . . . . ..... 68

19 A summary of grower responses concerning human sickness
from pesticides . . .. ..... .73

20 A summary of grower responses concerning damage from
pesticide drift . . . ... .. . 78

21 Workmen's compensation claims, State of Florida; work
injuries, days of disability, and cost by agency, for
disabling work injuries, 1962, 1963, 1966, and 1967 .. 82

22 Dollar costs of disabling workmen's compensation claims
for Dade County, Florida, 1966 and 1967, by kind of
payment and selected agents . . .... .. 83

23 A summary of data gathered from veterinarians in Dade
County .... ............. ....... 86

24 A summary of data gathered from the Community Studies
Program on Pesticides in Miami . . .... 92

25 A summary of the externalities incorporated in the
empirical model, Dade County, 1967 . . ... 95

26 Computer results for Policy 1 .. . . 98

27 Estimated average costs of chlorinated hydrocarbons
and organic phosphates used on crops in Dade County,
1966-1967 . . . . .. . 104

28 Estimates of average total production costs in Dade
County, 1966-1967, by crop and pesticide policy .... .. 106

29 Supply functions used for Policy 2 . . ... ..107

30 Computer results for Policy 2 ........... .108








LIST OF TABLES (Continued)


Table

31 A summary of annual insect control costs for tomatoes,
potatoes, pole beans, sweet corn, and squash ..


Page


109


32 A comparison between model solutions for Policy 1 and
Policy 3 at observed externality levels . . .. 111

33 Model solutions, illustrating the effect of an
environmental constraint, for alternative values of
C under Policy 1 . ... . . . 121

34 Model solutions, illustrating.the effect of an
environmental constraint, for alternative values of
C under Policy 2 .. . . . . 122
11
35 Value of the objective function partitioned by crops
and by whether value accrued to producers or consumers,
for the three policies under observed externality
conditions . . . . ....... 130


vii












LIST OF FIGURES


Figure Page

1 Locational map of Dade County, Florida . .... 13

2 Soils of Dade County, Florida . .... . 16

3 Population trends in Dade County, Florida . ... ..... 21.

4 Point estimate of externalities arising from the agri-
cultural usage of organic phosphates . . .... 35

5 An alternative hypothesis for externalities arising from
the agricultural usage of organic phosphates . ... 36

6 A linear iso-product function for chlorinated hydrocar-
bons and organic phosphates . . . . 102

7 A hyperbolic iso-product function for chlorinated
hydrocarbons and organic phosphates . .. .. .. 102

8 Accumulated residues from annual applications of one
pound of chemical whose half-life is T years . ... 114

9 Accumulated residues for three half-life situations
under two pesUicide reduction programs, pl and p2 ..... 116

10 Hypothetical pesticide usage through time .. ... .. 117

11 Hypothetical relation between pesticide usage and
residue of the ith pesticide in the kth environmental
element ... .. . .* * * 117

12 Observations on pounds of chlorinated hydrocarbons used
in 1966-1967 by farmers in Dade County and content
(parts per million) of these pesticides in eagle eggs
tested in the area . .... . ... ... 118

13 Marginal welfare productivity of chlorinated hydro-
carbons, Policy 1 ............. . .. ..123

14 Hypothesized relations between "welfare," the state of
technology, and the usage of chlorinated hydrocarbons 133


viii










CHAPTER 1

THE RESEARCH QUESTION AND THE HISTORICAL
DEVELOPMENT OF THE PESTICIDE ISSUE


The Research Question

The question which originally motivated this research was: "From a

socialwelfare perspective what is the optimum quantity and mix of pesti-

cides to use in agriculture?" As in most research projects, it was nec-

essary to narrow the original question before empirical research could be

initiated. The question was therefore modified in the following ways:

1. It was geographically limited to Dade County, Florida.

2. It was limited to the eight crops which account for the bulk

of agricultural activity in the County.

These restrictions mean that the research was essentially a case

study and that the general applicability of the conclusions is therefore

limited, but it is nevertheless hoped that some of the conclusions and

most of 'the methodology will have transferable value to other regions and

to other economic policy problems.

After these two modifications, the research question became: "What

is the best quantity of agricultural pesticides to use on the eight major

crops in Dade CounLy, Florida?"

From the outset the desire was to obtain quantitative rather than

qualitative answers to the research question. This desire dictated the

use of a mathematical model to describe the important relationships in

the problem. It was obvious that the parameters of the model would vary

depending upon the particular pesticide usage policy evaluated, and since









resources and data availability made it impossible to analyze a large

number of alternative policies, three were chosen for anlaysis.

Thus, the research question finally became: "Of the three pesticide

usage policies evaluated, which one results in the greatest net social

benefit from the crops studied in Dade County, Florida?"

Pesticides represent only one way to increase crop yields--by pro-

tecting the crop from various pests and diseases. Other factors that af-

fect yields are seed varieties, cultivation practices, fertilizers and

climatic conditions, to mention only a few. Some of these factors are

within the control of the farmer, while others are outside his control.

This research effort focused upon only the pesticide component of

the farmer's set of inputs. More specifically it was concerned with the

substitution of less persistent pesticides for the more persistent ones,

a goal recommended by the President's Science Advisory Committee [67].

The organic phosphates were used to represent the less persistent pesti-

cides and the chlorinated hydrocarbons to represent the more persistent

ones, a dichotomy which is valid for the majority of pesticides in each

group. The alternative policies were:

Policy 1. Current pesticide usage practices.

Policy 2. A 50 percent reduction in the per acre usage of

chlorinated hydrocarbons on the crops studied and an "induced"

increase in the usage of organic phosphates to maintain crop

quality and yield. This policy is one of a large number of

partial reduction policies that could have been hypothesized.

Policy 3. A "maximum substitution policy" which is believed

to include but is not limited to a virtual ban on chlorinated









hydrocarbons. It permits the substitution of other chemicals

for the chlorinated hydrocarbons and again assumes no changes

in crop quality and yields.

The effects of other factors of production such as seed varieties,

soil quality, and so on were generally assumed constant in order to ana-

Syze the effect of substituting one type of pesticide for another.

With this definition of the problem, the bulk of the research effort

centered on choosing a "yardstick" for net social benefits, setting up

the mathematical model, estimating the parameters for the model, and

finally generating the various model solutions on the computer.


Historical Development of the Pesticide Issue

Man's primary concern has always been the improvement of his living

conditions, and the domestication of food plants was an important step

in this direction. As human population increased, agriculture was inten-

sified and concentrated geographically in an effort to provide as much

food as possible with a minimum resource expenditure. This trend toward

intensification and concentration was accompanied by increased pest pop-

ulations, but the introduction of various pest control measures was suf-

ficient to keep the trend alive and provide a net improvement in man's

living conditions. His earliest efforts at chemical pest control con-

sisted of chemicals such as kerosene, arsenate of lead, nicotine, and

rotenone.

About 30 years ago DDT was developed, and for a time it appeared that

man had won the battle over harmful insects. But soon it became evident

that the insects were not to be vanquished so easily. They began to de-

velop a resistance to DDT just as bacteria had developed a resistance to








sulfanilamide. This marked the beginning of man's race to develop chem-

ical controls faster than the insects could develop an immunity to them.

It also marked the beginning of a controversy over the desirability of

injecting such chemicals into the environment.

Policy decisions regarding pesticide usage are generally concerned

with the quantities of pesticides which should be used and the methods

of influencing usage so as to obtain this "optimum" quantity once it has

been established. Many local, state, and federal bodies are seeking ways

of reducing the usage of persistent pesticides. It is usually their ob-

jective to eliminate the "non-essential" uses of pesticides and to substi-

tute non-persistent for persistent pesticides, where possible. Such a

policy assumes that pesticides are not being used in the "best" ways from

society's point of view. This study provides an economic methodology for

evaluating alternative levels of pesticide usage from a social welfare

point of view. It does not present a basis for evaluating alternative

ways of approaching the optimum level although the two questions may not

be independent. Various means of approaching the optimum level are dis-

cussed qualitatively in Chapter 7.

The term "pesticides" is commonly used to refer to the whole family

of agricultural chemicals "used to control insects, mites, ticks, fungi,

nematodes, rodents, pest birds, predatory animals, rough fish, plant di-

seases, weeds, and also to those which act as regulators of plant growth,

as defoliants, and as desiccants" [59, p. 41]. Major categories have

been described as follows [59, p. 41]:

1. The chlorinated hydrocarbons containing carbon, hydrogen,
and chlorine are the pesticides used in greatest tonnage.
The most familiar are DDT, dieldrin, aldrin, endrin, toxa-
phene, lindane, methoxychlor, chlordane, and heptachlor.









Among those used extensively as herbicides are 2, 4-D and 2,
4, 5-T for control of broad-leaved weeds in lawns, pastures,
'cereal crops, and brush growth along highways and fences.

2.. The organic phosphorus compounds, composed of phosphorus,
oxygen, carbon, and hydrogen, are used principally as insect-.
icides and miticides. Parathion, malathion, phosdrin, and
tetraethyl pyrophosphate (TEEP) are examples.

3. Other organic compounds include the carbamates, dinitrophenols,
organic sulfur compounds, organic mercurials, and such natural
products as rotenone, pyrethrum, nicotine, strychnine, and the
anticoagulant rodent poisons.

*4. Inorganic substances with a long history of use include copper
sulfate, arsenate of lead, calcium arsenate, compounds of
chlorine and fluorine, zinc phosphide, thallium sulfate, and
sodium fluoroacetate.

These categories are differentiated on the basis of chemical compo-

sition rather than major function. A commonly used functional taxonomy

is (1) insecticides, for the control of insects; (2) fungicides, for the

control of plant diseases; (3) herbicides, for the control of undesirable

weeds; (4) miticides, for use on mites; (5) nematocides, for the control

of nematodes; and (6) rodenticides, for use in controlling rodents.

With respect to environmental damage, it is obviously the chemical

composition of the pesticides rather than their functional use which is

of greatest importance in determining the behavior of the.pesticides in

the environment. A pesticide's environmental behavior is usually char-

acterized in terms of its toxicity, persistence and mobility. The.main

thrust of the environmental dispute focused on the chlorinated hydro-

carbons and the phosphates.1


A technical discussion of the behavior of these categories is
beyond the scope of this discussion. The interested reader should con-
sult Alexander [3, 4], Fredr, et al. [20], Hill and McCarty [26].








Since the chlorinated hydrocarbons are generally quite persistent

in the environment, their residues tend to accumulate in some elements

of the environment such as soil, water, and plant and animal tissue.

They are readily stored in the fat of many animals and are passed along

the food chains from prey to predator. Furthermore, there is a tendency

for predators to accumulate higher concentrations of residues than their

prey. This implies, of course, that.species at the end of long food

chains might be subject to greater hazard than those at the end of shorter

food chains. Filter feeding species such as the oyster also tend to ac-

cumulate large quantities of pesticides from the environment. This ten-

dency for residues to build up in certain elements of the environment,

called "biological magnification," has naturally created great concern

among ecologists although the significance of these residues is disputed.

Most organic phosphates are very toxic to man and animals, but they

tend to decompose rapidly into non-harmful substances and thus seldom

persist in the environment for long periods of time. Since their detri-

mental effects tend to be of an acute rather than chronic nature, organic

phosphates have caused many fatal and non-fatal poisonings in man. Edu-

cation in handling these highly toxic chemicals can be effective in re-

ducing acute damage.

For the (. S. as a whole, the chlorinated hydrocarbons are used in

greater quantities than other pesticide categories, but according to

estimates by the U. S. Department of Agriculture, total usage of this

category has fallen slightly since 1964 while the usage of organic phos-

phates has risen. Table 1 gives some indication of the quantities and

geographical distribution of farm usage of these compounds.










Taule .-Qua.tities Cf insc=i=dc ud =T =rps by far.er by georaphii regions. 196^A. q96, ira 1971


Chlorinated Organic Other Total synthetic organic
Region hydrocarbon phosphates
1964 1966 1971 1964 1966 1971 1964 1966 1971 1964 1966 1971


Total U.S. (48 states)

Northeast

Lake States

Coin BelL

NorLheur Plains







Southern Plains

Mountain


Pacific


--------------------------------------


1,583

1,692

11,790

61"



27,432




2,122
2,170


-Thousands of pounds-


82,779

1,542

1,761

15,599

484









3,096


3,970 2,444


51,876

1,192

449

9,651

372

3,705

23,171

1,332-.

3,:53

1,382


30,493

1,313

555

1,709

2,111

1,527

-4,25'



5,351

1,489


36,573 65,031


1,642

1,406

3,568

3,390

2,210
5,310


C 4,33



3,749


1,825

1,200

4,313

3,966

2,927





12, 371

3,547


6,337 5,501 8,450


15,4!6 12,394 24,238 135,744

2,334 1,431 1,347 5,230

844 756 2,605 3,0.31

547 1,374 3,815 14,046

25 624 3,205 2,749

1,292 1,055 2,991 !?.461
-.,--,-^------ -- -
2, 3,057 5 733 7 837

2,2'7 523 599 -27,061

1,2- 2,-23 1 ,929 19,600

270 64 476 3,929

2,433 1,107 1,538 12,740


a Source: [62, 63].


131,751

4,615

3,923

* 20,541

4.498

9.7?3

31 7007



15.981

6,909

9,052


151,145

4,364

4,254

17,779

7,543

9 g3

395.51



18,/65

5,405

11,454


----------------------------------------









Since a pesticide is usually not totally destroyed but only trans-

formed or moved about in the environment, the residual may enter the con-

sumption function and/or production function of persons who were not a

part of the decision that brought about the pesticide application. In so

doing, the pesticide residue becomes what economists call an externality

or an external effect.2 The external effect may be either beneficial or

harmful to the externally affected party. The principal point is that

the amount of the external effect cannot be controlled by the person re-

ceiving it. If a farmer's pest control activities result in fewer pests

in the fields of farmers around him, the neighbors have no control over

the quantity of these benefits which they receive. Similarly, if a far-

mer's use of pesticides results in a downward trend in wildlife that are

enjoyed by others, there is no direct economic signal to the farmer caus-

ing him to take account of these values in his decision.process. Extern-

alities create a desire on the part of externally affected parties to

participate in decisions leading to the externalities.

There are three ways in which a society may settle disputes caused

by externalities. One is by negotiation between the opposing parties.

A second is through the political or legislative process, and a third is

through litigation. Negotiation is usually preferred in our society and

is generally more expeditious, but some types of problems are not easily

resolved in this manner. Environmental pollution is one of these. Not

only is it difficult and expensive to organize the parties for negotia-

tion, but the configuration of property rights is not clear. This is


2 The concept of an externality is examined in Buchanan and Stubblebine
[11] and its relation to public policy in Edwards, Langham and Headley [14].








because the benefits and costs are not clear, for property rights tend to

be shaped by subjective notions of benefits and costs as illustrated in

the following passage from Prosser: a person is permitted

to make use of his own property or to conduct his own affairs
at the expense of some harm to his neighbors. He may operate
a factory whose noise and smoke cause some discomfort to others,
so long as he keeps within reasonable bounds. It is only when
his conduct is unreasonable, in the light of its utility and
the.harm which results, that it becomes a nuisance...The world
must have factories, smelters, oil refineries, noisy machinery,
and blasting, even at the expense of some inconvenience to those
.in the vicinity, and the.plaintiff may be required to accept and
tolerate some not unreasonable discomfort for the general good [48].

Economists have long recognized the existence of external effects but

their consequences have been largely ignored in economic analyses. Theo-

retical and measurement problems make it difficult to interpret their

meaning in a social welfare sense. To complicate matters, externalities--

especially those associated with environmental quality--seem to be inten-

sifying with new technology and population increases.

A socio-economic system which cannot interpret these external effects

may be forced to recognize them with seemingly arbitrary political action

in order to allow the necessary time for the solution of theoretical and

measurement problems. For example, far too little is known about the

environmental effects of persistent pesticides, but limited information

indicating that they may be detrimental has created social pressure for

banning their use until more is known about their long-run effects and

how to recognize these effects in making regulatory decisions.

If social benefits and costs are to be the major determinants of pub-

lic policy and property rights, then it behooves society to use the best

data available and to.develop more precise measures of social welfare.

One has the impression that in many such decisions policy makers have




10




used the pressure of constituents as the index of social welfare. Such

an approach does not encourage the objective appraisal of alternative

policies.










CHAPTER 2

AREA STUDIED


This chapter provides a brief description of the characteristics of

the area studied. Readers interested primarily in the methodology and

results may proceed to Chapter 3 with little loss of continuity.


Choice of an Area

The State of Florida was chosen for this study since it is an impor-

tant producer of agricultural commodities and a large user of pesticides.

However, the State as a whole was much too heterogeneous for effective

analysis, so a smaller geographic region within the State was chosen. The

focus rather quickly narrowed to three areas--a small isolated locale in

Northeast Florida (Hastings, Florida) heavily committed to the production

of potatoes and cabbage; an area in Central Florida (Polk County) which

primarily produces citrus; and the winter vegetables, ornamental horti-

culture, and tropical fruits area of Dade County. The latter area was

the final choice because it had what was believed to be the best workable

balance of needed characteristics. Its agriculture is highly dependent

upon pesticides and great quantities of them are used in the production

of its crops. It is relatively isolated by the Everglades Swamp and the

Atlantic Ocean. Dade County is also amenable to the observation of ex-

ternalities due to increasing urban-ruralinteraction as the growing city

of Miami encroaches on the agricultural interests in South Dade County.

In addition, several scientists are currently working on problems related

to the use of pesticides in that area.








Agriculture of Dade County

When its boundaries were first designated in 1836, Dade County com-

prised most of Southeast Florida. Its first county seat was located at

Juno, north of what is now West Palm Beach. In these early days the in-

dustry of the area consisted of starch production from coontie, one of

the native plants. Following the "great freeze" of 1894 (which almost

wiped out the citrus groves in Central and North Florida) Henry Flagler,

seeing Dade County had escaped all damage, extended the railroad all the

way to Miami and built a hotel there. This was to mark the beginning of

the great development of the area.

Today, the boundaries of the County have been reduced to the south-

eastern part of the Florida peninsula, as indicated by Figure 1. It ex-

tends about 55 miles from north to south and 47 miles from east to west.

Total area is 2,054 square miles, or 1,314,560 acres. Miami, the county

seat, and other towns are located in the eastern portion of the county

near the coast.

The surface relief is nearly level, and much of the county lies less

than 13 feet above sea level. But a few low ridges in the eastern portion

are slightly higher than 20 feet in elevation. In the western portion the

surface water drains slowly through the peat marshes in a southerly and

southwesterly direction to the Gulf of Mexico. In the eastern portion the

indistinct drainageways of the peat marshes join many of the canals and

ditches which extend through the low sandy and rock ridges to the Atlantic


1 We are indebted to the Dade County Agricultural Agents' Office for
most of the information contained in this section.

































... i ii -



































e a* *rC *
























IC m.nrI O*iw cr






















Figure l.--Locational map of Dade County, Florida








Ocean. All major canals in the northeast and southern part have control-

dams for regulating water levels, but very few pumps are used for con-

trolling water levels in fields except on several large farm operations.

Most of the southwestern part of the county is included in the Everglades

National Park.

Dade County enjoys sub-tropical climatic conditions not found else-

where on the U. S. Mainland. It is 500 miles further south than Los

Angeles, but it is not subject to the heat of the tropics due to the

nearness of the Atlantic Ocean, the Gulf of Mexico, and the prevailing

tradewinds. The mean annual temperature at Miami is 75F., and the mean

annual rainfall is 57.8 inches. Most of the rainfall comes during the

summer months. Occasionally, disturbances of hurricane type move across

the county during the months from August to November. Killing frosts may

occur from the middle of December to March, but many winters, sometimes

several in succession, pass without damage from freezing temperatures.

Livestock graze the pastures throughout the year and need little shelter

from the weather. Taken together, the climatic conditions of Dade County

make it one of the most unusual and productive farming areas of the nation.

September through March are the months of primary agricultural activ-

ity. Winter vegetables, ornamental horticulture, and tropical fruit are

the three largest activities, representing 44.3, 11.5, and 4.1 million

dollars, respectively. Minor agricultural activities are poultry, dairy

and livestock. Tle agricultural activity of Dade County is summarized in

Table 2.

Most of the fruit and vegetable crops in Dade County are grown on

two soil types, marl and rockland, illustrated in Figure 2.







Table.2. --.A.;icultural production in Dade County, Florida, 1966-1967a


activity Crop Units of Value of
Activity
acreage output output

- Thousands-- -
Vegetables
Tomatoes
Fresh 19,000 5,806 crates $23,050
Processed 1,514 crates 961
Potatoes 7,660 1,564 cwt. 5,474
Snap beans
Bus 1,470 181 bu. 699
Pole 5,830 1,647 bu. 6,357
Squash 3,080 457 bu. 1,942
Strawberries 670 657 flats 2,214
Corn 1,650 252 crates 622
Cucumbers 1,290 204 bu. 787
Cabba g: 470 189 crates 312
Okra 400 36 bu. 180
Peas 650 69 bu. 361
Cuban vegetablesb 1,360 1,102
Other vegetables 390 272
Total vegetables 43,920 $44,333
Ornamental Horticulture $11,530
Fruit
Avocados 5,235 220 bu. 1,232
Limes 3,585 640 bu. 1,965
Mangos 1,520 70 bu. 490
Specialty fruit 440 210
Other fruitd 365 247
Livestock and Livestock Products 11,145 $4,144
Dairy.'
Milk 2,507 gal. $1,503
Cull-animals 166
Poultry
Eg" 3 5,220 doz. 2,034
Cull. birds 150 head 40
Hatchery chicks 10,040 head 1,450
Other (including beef cattle,
horses, etc.) 5,032 head 796
Other farm enterprises 500

aSource: Dade County Agricultural Agents Office, Homestead,
Florida.

Includes lima beans, cantaloupes, eggplant, escarole, chicory,
lettuce, green peppers, and green onions.

SIncludes lychee, barbados cherries, guava, papyas, and sapodillas.

d includes oranges, grapefruit, tangerines, tangelos, and lemons.













































Figure 2.--Soils of Dade County, Floridaa



a Reprinted with the permission of the Dade County Agricultural
Agents OfEice.








Marl and its various phases comprise a total of about 317,000 acres

in Dade County. Surface soil is a light brown or brownish gray marl of

silt loam texture. The subsoil is lighter colored, and the underlying

material is Miami oolite. Native vegetation on these soils consists of

a variable mixture of sawgrass, myrtle, bay, and cypress. Elevation

above sea level of most areas of marl that are suitable for cultivation

ranges from about 8 feet near the rock ridge to 1 to 2 feet near the shore

line. Soil depth varies from 6 to 60 inches. Marl has poor internal

drainage and becomes waterlogged or even flooded during the rainy season;

Occasionally, wet conditions occur during the normally dry winter season;

however, this soil may, at times, become too dry during the winter. Both

drainage and irrigation systems are used extensively for crop production.

Marlis alkaline in reaction, and the application of certain of the

minor elements is imperative for successful crop production. Prior to

discovery of the low availability of manganese, this unknown deficiency

limited cropproduction in the area.

Marlsoils are utilized for production of winter vegetables, includ-

ing Irish potatoes, tomatoes, bush beans, pole beans, squash, cucumbers,

corn, strawberries, cabbage, beets, lettuce, escarole, peppers, and egg-

plant. .The total acreage of marl soils cultivated in these vegetable

crops has averaged 18,000 to 20,000 acres annually for the past 15 years.

There ,are,approximately 279,000 acres of rockland in Dade County.

The rockland area extends roughly from U. S. Highway 1 west to the

Everglades Park boundary and from the Tamiami Trail on the North to Florida

Highway 27 leading to the Everglades Park.

The rockland is an oolitic limestone formation with many solution








holes and is relatively soft until it is.exposed to the air. The solu-

tion holes below the surface act as storage places for water. Near the

surface, these cavities are filled with loam and loamy fine sand having

varying shades of red coloring.

Prior to 1938 farming of the rockland was confined to the larger

solution holes and to pockets broken up by dynamiting. Heavy tractors

and scarifying equipment are now used to chisel or "plow" this soil so

that all of the area can be farmed. Vegetable farms are plowed 6 to 8

inches deep over the entire field. Orchards are planted in trenches that

have been cut and crushed to a depth of 20 to 24 inches. The trenches

are back filled after cutting, and young trees are set in the crushed

rock trench that is formed.

Irrigation wells are drilled into the oolitic rock 15 to 40 feet

deep and usually about 300 feet apart. No casing is required. One-half

to an inch of water is applied by overhead irrigation each week. Most

farmers use a single irrigation head on a portable pump, which covers

roughly two acres.

Only vegetables that produce marketable products above the ground

such as tomatoes, corn, squash, beans, cantaloupe, okra, southern peas,

and leaf crops can be grown on rockland. Tree crops in Dade County in-

cluding limes, mangos, and avocados, are grown exclusively on rockland

soils. During the last 15 years, an average of 28,000 acres of vegetable

crops have been produced on rockland soils, and an average of 20,000

acres have been devoted to tree crops.

Both marl and rockland soils are underlaid by Miami oolitic limestone,

which is perforated with numerous vertical solution holes. The oolite








underlies theAtilantic Coastal Ridge south of Boca Raton in Palm Beach

County to an average depth of about 20 feet. Deposits are thicker near

the coast .and then fan out to a feather edge in western Dade and Monroe

Counties. It overlies the Tamiami formation, another porous limestone.

These two limestone formations make up the Biscayne Aquifer, the main

source :of water for Dade County.

Of the total land area in Dade County (1,314,560 acres) about 117,000

acres or 8.9 prc-eent was apportioned to farms in 1964; in 1959 129,000

acres of 9.8 percent was in farms. Although some growers stated that

suitable farm land is becoming difficult to obtain, it is more likely that

other constrain .ic, such as markets and capital and labor requirements, are

more resi-r.ct-iv. than the physical quantity of land.

Metropolitan Dade County is one of the youngest and fastest growing

major citrp'clit.:: areas in the United States. Between 1890 and 1962,

a span of 72 years, the population increased from 861 to more than 1 mil-

lion parsons. BetweLen 1950 and 1960 the population increased almost 90

percent-as indicated in Table 3.

Currently, the population of the county is estimated at about 1.1

million by the Metropolitan Dade County Planning Department, and will

approach 2.55 i-til.ion by 1995 if the current growth-rates continue. The

Planning Dep.nrcr-int estimates that 130 additional square miles will be

needed for-,new homes and apartments to accommodate the additional 1.5

million new residents expected during the next 25 years. The effect of

this growth on the outlying areas is shown in Figure 3.

It is obvious that the projected population growth will have serious

implications for the rural interests in Dade County. Agricultural








Table 3.--Florida and Dade. County population changes
from 1950 to 1960a

Unit Florida Dade County


Total 1950 No. 2,771,305 495,084
Total 1960 No. 4,951,560 935,047
Increase % 78.7 88.9

Rural 1950 No. 957,415 29,005
Rural 1960 No. 1,290,177 40,705
Increase % 34.8 40.3

Urban 1950 No. 1,813,930 446,079
Urban 1960 No. 3,661,383 894,392
Increase % 101.9 91.9


aSource: [58].


activities will be driven toward the Everglades Swamp on the west and

southwest. Interdependencies between urban and rural interests will in-

tensify, and concurrent with this intensification, economic externalities

arising from such propinquity will increase, giving rise to a multitude

of policy questions such as the one with which this study is.concerned.

Several other characteristics of Dade County and its farmers should

be noted. First, farming in the region requires large amounts of capital

relative to other areas of the State. The 1964 Census of Agriculture

indicates that the investment in land and buildings per acre of farm land

is $1,088.12 in Dade County against $285.71 for the State [57, p. 304-305].

For the U. S. as a whole it is $143.81 [56, p. 792].

Second, revenues per acre from farming in Dade County are also very

high. The per acre value of all farm products sold in Dade County is

$443.13 against $68.41 for the State [57, p. 332-333]. For the U. S. as



























Il Existing 1 mil-
Slion population

i Proposed 2.5
millionin populari


Figure 3.--Population trends in Dade County, Floridaa


a Reprinted with the permission
Planning Department.


of the Metropolitan Dade County










a whole this figure is $31.79 [56, p. 802]. And finally, the general

level of farming technology in Dade County appears to be relatively high.

Some of the larger growers have professional entomologists on their pay-

rolls, and most pesticide firms in the area employ entomologists to sell

pesticides and to provide consultation to the farmers. The University of

Florida has an experiment station in Homestead, Florida, that is very

active in the area of insect and disease control. In addition, the Dade

County Agricultural Agents Office, the largest in the State and located

in Homestead, is extremely active in disseminating information to the

farmers.









CHAPTER 3

THE EMPIRICAL MODEL


Mathematical Statement of Model

The-model used for this analysis employed a measure of welfare (an

objective function) consisting of consumers' plus producers' surplus,

modified for observable externalities neglected in the surplus calcula-

tion.1 For each of three specified pesticide usage policies, the model

maximized this objective function over production of the eight major crops

in Dade County, Florida. Finally, the policies were ranked by their max-

ima. The model can be stated in general terms as follows:

For a set of subjectively chosen pesticide usage policies, r, r = 1,

..., s, rank the associated estimates of welfare, Wr, where:


nj y. m
(1) W = maximum: E { J [f. (y) gc (y )] dy j E [h (zi)]
r j=l 0 i=l
y
Yj
j = 1,..,, n
zn
1 i = 1,..., m
r = 1,..., s

1
A discussion of consumer surplus and producer surplus can be found
in most economics textbooks. For linear demand and supply functions, con-
sumers' plus producers' surplus is the shaded area in the following graph:






K s




D


quantity

23









where the maximization for a given policy r is subject to:

n
r
(2) E a.. y z. = 0
j=1 1 1

(3) Cki (zi) < Ck k = 1,..., p

(4) yj, z. > 0


where:

f. (y.) = demand function for the jth crop;

S y = acres of the jth crop;

g (y.) = supply function for the jth crop under the rth policy

alternative

hi (zi) = an externalityy function," a functional relationship be-

tween observed external effects expressed in dollars, and

the quantity of the ith pesticide;

zi = quantity of the ith pesticide measured in pounds of 100

percent active material;

atj = the quantity of the ith pesticide used per acre of the jth

crop under the rth policy;

cki (zi) = a function describing the accumulation of the ith pesticide

in the kth environmental element in response to the usage

of pesticide k;

Cki = an arbitrary upper limit on the ith pesticide residue in

the kth environmental element--a parameter to be determined

"politically."

Since Marshall first developed the concept [42], economists-have vacil-

lated about the use of consumers' and producers' surplus as a measure of







2
social welfare. Hicks [25] and Hotelling [27] helped revive professional

interest in the concept, and it now appears to have a growing acceptance

an an approximate measure of the welfare aspects of various social alter-

natives [55]. One of its greatest advantages is probably the fact that it

is empirically operational. Its major disadvantage lies in the fact that

any function attempting to measure social welfare must rest on rather strong

assumptions. Let us, then, enumerate the additional assumptions underlying

the model.

1. Income effects of price changes have a negligible effect on the

welfare function. The model also divorces itself from the ques-

tion of whether or not current income distributions are optimal.

2. The model ignores differences in the marginal utility of money

among effected parties. Lerner [38, pp. 23-40] argues that in

the absence of knowledge to the contrary this is the most reason-

able approach, but such an argument, resting on the absence of

knowledge is not very comforting.

Nevertheless, the assumption that men are all very much
alike is the foundation of democratic institutions ("We
hold these truths to be self-evident...").and we certainly
do not attempt in politics to give the voter a number of
votes in proportion to his intelligence and his ability to
use them. The one-man-one-vote principle is forced upon
us by the recognition of the practical impossibility of
any other [7, p. 93].

So it.is with the issue at hand. Some people probably derive

greater utility than others from an incremental dollar (or greater

disutility from losing a dollar), but it was a practical impossi-

bility to recognize it in the.analysis.

2 Samuelson has perhaps been one of its most severe critics. See
Foundations of Economic Analysis [51, pp. 208-209].








3. The model is static with respect to time. That is, it ignores

shifts through time in the functions that comprise the model.

4. The model assumes that demand and supply functions for a crop

are independent of those in other regions, those for other crops,

and those in other industries.

5. Agricultural inputs taken out of production can be utilized with

equal productivity in activities (agricultural or non-agricultur-

al) not included in the model.

6. The externality functions for chlorinated hydrocarbons and or-

ganic phosphates are assumed independent.


Estimates of Model Parameters

The Demand Model

The model which provided that basis for estimating demand parameters

for the objective function was specified as follows:3
for the objective function was specified as follows:


(5) q(t) =

subject to:

(6) q(t) -

where:

q(t).=

p(t) =

I(t) =


q(t) =

u(t) =


O + 1 p(t) + T2 I(t) + u(t)



q(t-1) = q[r(t) q(t-l)], 0 < 0 < 2



the long-run equilibrium quantity as of period t;

price of the commodity in period t.

per capital disposable income (deflated) in period t for the

United States;

the quantity demanded in period t.

a disturbance term satisfying the following assumptions:


3Since this model was used for all crops, the crop designation, j,
is omitted.




27



(a) u(t) ,is normally distributed with mean as in (b) and variance and

covariance as in (c).

(b) E[u(t)IX] = 0, where X is the matrix of observations on stochastic

variables p(t) and I(t).
2
(c) 1E[u(t)u(t+s)JX] = 0 for s # 0, a -for s = 0.

The matrix X must also be of full rank.

The constraint, (6), simply describes the adjustment toward the

long-run equilibrium quantity.

By substituting equation (6) into equation (5) one can obtain the

following function, which was empirically estimated: I

(7) q(t) = T0 + (l-p) q(t-1) + lT1 p(t) + ir2 I(t) + Wu(t)

The primary purpose of empirically fitting equation (7) was to obtain i

estimates of the price elasticity of demand after allowing for the average -

effects of .I(t) and q(t-l). Data availability necessitated using State ,

rather than Dade County data. It was assumed that the price elasticity

for Dade County would be the same as that for the State since they compete .

in the same markets and since, in some cases, Dade County represents a
6
relatively high proportion of the State acreages. Estimates of long-run

4I
If 0 < < 1, q(t) approaches q(t) asymptotically. If i = 1, the
entire adjustment is accomplished in one period. If 1 < 4 < 2, q(t) over-
adjusts, but still converges upon q(t). Lagged variables have been in-
creasingly employed in-econometric work in recent years [21, 36, 45].

5In this equation, however, u(t) is no longer independent of q(t-l),
the independent variable [30, p. 212; 41, p. 129]. The result is that the
least squares estimates are biased but have the desirable asymptotic pro-
perties of consistency and efficiency.

6 Dade County accounted for the indicated proportions of the State
acreage in 1966-1967 for the following vegetables:








price elasticity were thus obtained using the formula,
( 3qg(t) .p -
(8) E =.* = T
p)(t) 1-
q q

where p and q were the means of the variables from State data, and T the

estimate of T1 in equation 5.7 Then, using this estimate of-E and the

1966-1967 price and quantity for Dade County, a linear demand function

of the following form was synthesized for farm products produced in Dade
8
County:

(9) q = B.+ 0 1 p


Percent of State
Crop acreage in Dade County
Tomatoes 39
Winter potatoes 64
Beans 12
Corn 3
Squash 36

In two cases which will be noted later, the variables were trans-
formed into logarithms. For these the regression coefficients were the
required estimates of elasticity.

8For each crop the function was derived as follows:

E = t I
1 -
q

where: E = estimated long-run price elasticity;
p = average price from State data;
= average quantity from State data;

TI = an estimate of Tl in equation (5).

apd E = p=T .
Dp d p 1 p
q

where: = partial derivative of q with respect to p and the subscript
d indicates Dade County;
q = 1966-1967 quantity for Dade County;
p = 1966-1967 price for Dade County.








'The average effects of I(t) and q(t-l) on q(t) are, of course, recog-

nized in these simplified functions since I(t) and q(t-l) were included

as variables in the estimation of equation (7).

Equation (9) was then manipulated algebraically to make q the inde-

pendent variable. At the same time the unit of measure on the quantity

variable was converted to acres by dividing the equation by the average

yield per acre of the past 10 years. This led to demand equations expres-

sing price as a function of quantity (y).which were used in the objective

function as f (y.), j being the crop designation.

The conversion of q, units of production, into y, acres, via the

average yield per ,acre was done in order to express the demand functions

in the same units as the supply functions. Such a conversion abstracts

from the uncertainties of weather on crop yield and rests on the concept .

of:,an average expected yield per acre.


Using the point slope form of a linear function passing through q and
p yields: :

-p d p -. -P .- p
q
S T1P T1Pq A
q = q [ 1 -- ] + q (l-E) + -p ;
p
q qP

or: q= gO + gl p :'

wheree: P30 =q (l-E) and 1 P =

This, of course, does not necessarily yield the same equation as one
would get had the direction of minimization of the -sums. of squares of re-
siduals been in the direction of the p(t) axis. Initially, p was defined as
the independent'variable because observations on p were thought to be more
accurate than those on q. Johnston [30, pp. 148-176] offers a treatment
of observational errors in the variables.








Alternative data series (seasonal as well as annual data) were tried

in estimating the demand functions. In using seasonal data, the desig-

nated seasons were fall (September through November), winter (December

through February), and spring (March through May). Zero-one variables.

were used to allow for the average seasonal effect. If an observation

occurred in the fall, the fall variable was assigned a value of 1, other-

wise 0. If an observation occurred in the spring, the spring variable

was assigned a value of 1, otherwise 0.10 The effect of this dummy vari-

able technique was to shift the intercept of the demand function in an

attempt to recognize seasonal shifts in demand.11 A logarithmic trans-

formation of the variables was also tried. With the exception of beans

and mangos, these transformations provided little or no improvement in the

fits obtained. Table 6 in the Appendix to Chapter 3 presents the empiri-

cal results which were selected for derivation of the demand functions

used in the model. Although not of interest for purposes of this study,

short-run price and income elasticities are also presented. Table 4 pre-

sents the demand functions which were used for the model.


The Supply Model
r
The second element of the objective function, depicted by g (y), was

a linear supply function for the jth crop under the rth policy alternative.

The model from which supply parameters for current pesticide usage were


10
The winter season is recognized in the intercept and therefore does
not have a zero-one variable assigned to it.
11
It should be noted that only the intercept changed in this model.
In other words, the demand for fall tomatoes was assumed to differ from
that of winter tomatoes only in level, not in slope.








TabiJa 4.--Demand functions used in the model


Crop Function

Tomatoes p = 2069.1855 .0451 y
Potatoes p = 1121.0478 .0531 y2
Beans p = 1860.9877 .1322 y
Corn p = 799.6781 .2562 y
Squash p = 1317.1306 .2229 y5
Avocados p = 418.5657 .0351 y6
Limes p =.3014.9169 .6881 y7
Mangos p = 556.2577 .1539 y8


aFor all functions, price is measured in dollars
per acre and quantity in acres.


estimated was specified as follows: :

(10) y(t) = + 1 p(t-l) + v(t)

subject to:

(11) y(t) y(t-l) = 6[y(t) y(t-l)], 0 < 6 < 2

where:

.y(t) = long-run equilibrium acreage as of period t;

p(t) = price of the commodity in period t;

y(t) = acres planted in period t;

v(t)- a disturbance term satisfying-a similar set of assumptions

:as those given for the demand model.

As in'the demand model, the constraint described the adjustment to-

ward the long-run equilibrium acreage. Using (11) to eliminate y(t) in

(10) yields:

(12) .y(t) =-50 + (1-6) y(t-1) + 6F p(t-l) +.6v(t)








Equation (12) was empirically fitted and the results used to obtain esti-

mates of the long-run supply elasticity. Results are shown in Table 7

in the Appendix to Chapter 3.

As in the development of the demand functions, the estimate of

elasticity and the 1966-1967 price and quantity observations for Dade

County were then substituted into the point-slope form of a straight

line to obtain the equations for the supply functions. These equations

for Policy 1 were than solved for p in terms of y in order to conform to

the requirements of the model (Table 5).


Table 5.--Supply functions used in the modela

Function


Tomatoes
Policy 1 p = 144.3933 + .0563 yl
Potatoes
Policy 1 p = 318.6453 + .0517 y2
Beans
Policy 1 p = -2222.8585 + .5683 y3
Corn
Policy 1 p = -141.5558 + .3143 y4
Squash
Policy 1 p = -678.3921 + .4250 y5


aFor all functions, price is measured in dollars
per acre and quantity in acres.


Since equation (10)includes price lagged one time period, the supply

and demand equations constitute a cobweb model which, for purposes of the

study, is assumed to be in equilibrium at the 1966-1967 price and quantity.

The objective is to determine what happens to this point of long-run equi-

librium when externalities are recognized. There was no interest in the








time path of price-quantity changes but only in the magnitude of change

in the point of long-run equilibrium.12

In the case of avocados, limes, and mangos, data did not exist to

permit the estimation of supply functions, but it was possible to esti-

mate picking, packing, hauling, and selling cost on a per acre basis,.and

these were.subtracted as constants from the demand functions in order to

give a more accurate estimate of consumer surplus. Since these costs did

not fully represent the "true" marginal cost function, it was also neces-

sary to restrain the grove acreage in the optimization model. This was

done at the 1966-1967 level.


The Externality Function

There are two ways in which the model can accommodate externalities,

Those which can be objectively valued in monetary terms can be recognized

"through what.we call the externalityy function." Those which cannot be

adequately valued in monetary terms can be recognized through the "envi-

ronmental constraints." The relation between the environmental constraints

and the objective function is discussed in the next section, and the im-

portance of this constraint for wildlife is discussed in the section en-

titled "Environmental Constraints and Wildlife" in Chapter 6.

In order to specify the externality function, an attempt was made to

by-pass the physical cause and effect relationsihp that exists between

pesticides and externalities. The effort was aimed at relating a dollar

12
1If the system gets out of equilibrium, cobweb theory [16, pp. 255-
280] states that the time path of price and quantity will be convergent or
divergent depending upon whether the absolute value of the slope of the
supply function is greater or less than that of the demand function. In
the case of potatoes, the relative slope of the supply function to the
demand function would indicate a barely divergent path. All others are
convergent.








measure of the social costs of externalities to the amount of a pesticide

being used. The objective was to obtain structural estimates of the func-

tion:
2
(13) Ext = E [h. (z )]
i=l 1

where Ext is a dollar measure of externalities and z1 and z2 are pounds of

100 percent concentrated chlorinated hydrocarbons and organic phosphates,

respectively, used in Dade County.

Since time series or cross sectional data were not available on ex-

ternal dollar damages or pesticide usage, it was possible to observe only

one point on the function. The explanations for the point estimates of

pesticide usage and externalities are developed in Chapter 4 and 5. The

purpose of this section is to explain how the point estimates were inte-

grated into the model.

The diagnosis of pesticide poisoning of humans was found to be rela-

tively imprecise. If pesticide poisoning was diagnosed, it was usually

attributed to an organic phosphate--most often parathion. The total cost

estimate of about $4,600 for the 1966-1967 crop year in Dade County includ-

ed those cases about which there was doubt, and in this sense; was biased

upward for the organic phosphates.

There was very little substantive information on externalities attri-

butable to the chlorinated hydrocarbons. If damage was caused by this

group of pesticides, it was of a chronic, long term nature which could not

be adequately observed and valued at the time of the study. In an effort

to partially overcome this shortcoming, sensitivity analysis was used on

the externality function to observe the effect of higher levels of damage

on public welfare. This will be explained later.








At this point our data could be illustrated asshown in Figure 4.

(Ext)
($)




,$4,600 -0


134,000 z2 lbs. (organic phosphates)


Figure 4.--Point estimate of externalities arising from the agricultural
usage of organic phosphates


The point estimate of externalities due to the organic phosphates in 1966-

1967 was $4,600 and the corresponding organic phosphate usage on the eight

crops was 134,000 pounds. The significant question then centered on the

shape of the function that passes through this point. Since there-was no :

way to observe the function empirically, it was necessary to assume a

functional form and to rely on sensitivity analysis for some indication

of the solution's response to changes in the assumption.

We began byassuming a linear relation passing through the origin ':

between externalities and organic phosphates and between externalities

and chlorinated hydrocarbons. Thus the externality function could be de-

picted as: '

(14) Ext = z. + Oz2, where c and 0 are marginal externalities per pound

of 100 percent active chlorinated hydrocarbons and phosphates, .

respectively.

The observed level of acute externalities was $4,600, so the value of

0 necessary to pass the linear function through the origin and the observed

point was .034. The model was solved a number of times allowing 4 to take
.3 (









on values from 0.0 to 20.0 and 0 to assume values from 0.0 to 5.0.

It was the prevailing a priori consensus that instead of being a

linear function in the z2 dimension, externality function was shaped

as in Figure 5. This figure implies that as organic phosphates increase,

externalities increase at a decreasing rate. In order to test the influ-

ence of this hypothesis on the model solution, the following externality

function was used:

(15) Ext = +z + z2

where:

< varied from 0.0 to 5.0 in increments of 1.0;

S=.71

The parameter, X, was established by forcing the function to pass

through the origin and through the observed point on the function. Solu-

tions which resulted from the use of this nonlinear approximation of the

externality function were quite similar to those derived using the linear

function.



(Ext)
($)




$4,600 -

134,000 z2 Ibs. (organic phosphates)



Figure 5.--An alternative hypothesis for externalities arising from the
agricultural usage of organic phosphates








Constraints


on the Objective


Function


The objective


function


is subject


to three


types of


constraints.


The first,


= 1,.


--


simply


insures


that


quantity


of pesticide


is exhausted


in its appli-


cation


over


n crops.


second


constraint,


= 1,


called


"environmental


constraint,


says


that


the residue


of pesticide


i in the kth


environmental element


shall


be allowed


to exceed


Cki*
Cki


politically


determined


value.


This constraint


extremely important


from


a conceptual


point


of view,


for this


is the


route


by which value


judgements


externalities


amenable


to monetary


expression gain admission


model.


data needed


to activate


the environmental constraint


do not


presently


Because


exist,


the type


so the constraint


of data needed


could


for this


be included


constraint may be


in the model


great


-runs.


inter-


est to ecologists


conservationist


further


comments on


concept


an environmental


relations


are


constraint


included


and some model


in the section entitled


solutions using hypothetical


"Environmental Constraints


and Wildlife


in Chapter


third


constraint


on the objective


function,


simply


prohibits


optimizing algorithm from producing negative valued


- A- .2 -





























APPENDIX


TO CHAPTER 3:


EMPIRICAL RESULTS


OF THE DEMAND


AND SUPPLY MODELS









Coefficients of: b ber
ter t d Number of
q(t-l) p(t) Zt) S d observations
5--..


(.1262)-
777.S52 .578
(.2553)
3317.03S3 .1173
(.0672)
-753.6753 .2774
(.1551)
-.0464
(.1014)
1130.4805 .3805
(.1850)
30.9556 .4280
(.2587)
.6427 .0896
(.1805)


-131'74=123 -
(255.6010)
- 32i.145:
(175.9172)
- "=.4;G1
(53.8774)
- 718.3669
(275.4565)
- 127.5262
(15.8604)
- 44.3303
(13.6422)
- 11.3824
(21.8403)
- 1.2548
(.2088)


(.7925)

(.7423)
-.00,
(.1269)
1.77435
(.5416)
.1401
(.0770)
5.7642
(4.2249)
.1167
(;1344)
1.5275
(1.3004)


(567.5403) (380.2429)
(567.5403) (380.2429)


13 .t5 .7072


-- 612.023
S(76.5858)
- 475.4553
(284.9011)
271.4363
(32,6967)


-f 7.'n952
(76.1586)
2863.2954
(823.1529)
-201.2628
(30.2328)


* --0


39 .3351 -.:40 -1.410

39 .9480 .5444 .S918

39 .7456 .9610 .9183


Winter pot:tcas




Coca3

-h
Squash

Avocadosk

Limes"


.E532 210


1.3502 1 32:4


.6567


-1.2800 1.2882 2.0795


- .2222


.6272 1.0965


12 .9131 -1.2548 -1.3783 1.5275 1.677s


Sources of data: 1. Tomatoes, potatoes, beans, corn and squash: Florida Agricultural Statistics [18]; 2. Avocados:
Statistics [60]; 3. Limes: a. Production and on-tree prices: Florida Agricultural Statistics [18), b. Packinghouse prices:
Statistics [60]; 4. Mangos: Dade County Agricultural Agent's Office, Homestead, Florida.
b
Standard errors of the coefficients are shown in parentheses.
S I per capital income.
Sf-a "dummy variable" which equals 1 if the o s-:.:Ilan occurred in the fall and 0 otherwise.
S a "dummy.variable" which equals I if the observation occurred in the spring and 0 otherwise.
Quantity measured in thousands of 60 pound crates; price measured in dollars per crate.
Quantity measured in thousands of 100 pound bags; price measured in dollars per bag.
Quantity measured in thousands of bushels; price measured in dollars per bushel.
This function was estimated in natural logs.
SQuantity measured in thousands of crates; price measured in dollars per crate.
SQuantity measured in tons; price measured in'dollars per ton.
Quantity measured in thousands of boxes; price measured in dollars per box..
a Quantity measured in bushels; price measured in dollars per bushel.


18 .506S .7929

18 .4832 .1271


S Short-run
Selastcit
elasticity


Lang-run

elasticity


Short-run
easicity
elasticity


Long-run
elasticity
elasticity


Agricultural
Agricultural


rC-J-I -. -..---- -~----ir---_-... -m---


--


---------l--x----l --~L


-*1.*.17" 1 2 .C^cO I.S2C


-.001t


-.bCeC





b
Coefficients of: b o
Crop Intcepumber of R2
Crop IntrcepLc d observations
y(t-1) p(t-1) Sc Ss ooser

Toinaoese -30833203 .4r 235. .03'9 2 3. 1,1028 27.750? 39 .6541
(.1312) (903.0129) (1530.5461) 1222.1824

Winter potatoesf, 1.6366 .7706 .4140 13 .6462
(.1889) (.2335)

Beans 4037.1562 .6600 704.1148 --59.9844 -38.7480 39 .4988
(.1272) (811.0100) (1079.1404) (1111.8496)
i
Corn -1882.9492 .6440 1969.7227 1535.6630 10277.5620 39 .9595
(.1279) (1495.8831) (1460.8706) (2874.7993)

Squashg 2.8217 .6338 .1764 .0061 .00875 39 .4243
(.1592) (.1267) (.0832) (.0752)


Sources of daLa: T..a'.:teS, potatLs, bea-as, tor, an .T- h: ('1ra Agrf-icltu-al St Ptise (181.
bStandard errors of the coefficients are shown in parentheses.

c Sf = "fIli "' riabi" ;:ihich equ-ls 1 if the ;:s:etic- occu-rred .n the fall nnd (0 i--harviv:,
-Id t


Long-run
price
elasticity

1.1351


1.8047


.3291


.7270


.4817


I


Short-run
price
elasticity

.5663


.4140


.1119


.2538


.1764


* k










CHAPTER-4

APPLICATION OF AGRICULTURAL PESTICIDES IN DADE 'COUNTY


The information contained in this chapter provides a.descriptive

background on pesticide usage in Dade Countyand the pesticide usage

estimates needed for the specification of the -exterality function dis-

cussed in Chapter 3. Readers not interested in the detail of the pesti-

cide externality estimates may proceed to Chapter 6, page 97.


Technology of Pesticide Application in Dade County

Pesticide spray programs in Dade County vary widely among growers

depending upon the crop involved, the form of the pesticide being used,-

the method of application, cultivation practices, and the insect or di-

sease infestation. The term "spray program" is something of a euphemism

to describe the sum total of a farmer's spraying activities during a-sea-

son. The typical farmer in Dade County inspects his fields daily, some-

times with an entomologist accompanying him. When he finds what he con-

siders to be a:serious insect infestation, he decides what spray(s) to

use and takes immediate action. Some farmers will tolerate a higher in-

festation than others before spraying. Most farmers keep historical

--of what pravp-. iWPr P. I'sllt13, IIhe Pn thlP er orpi 'PI l, I d p (5 0 trrl T InsI, tltitif Pos

were applied. However, these records serve more to protect the farmer if

.ons are raised regarding residues than for future decisions regard-

insecticide spraying. Many farmers, however, do use a fixed program

(spray, quantity, date) for fungicide spraying in the control of disease.

There seemed to be little interest among growers in "production-







function-type-concepts." They recognized the need to spray in order to

prevent crop losses from insects-and diseases and to produce a crop of

marketable quality. But they were uninterested in a more precise rela-

tionship between spraying and yields or between spraying and infestation

of insects or disease. This attitude is possibly due to their "all en-

grossing" concern about weather variables and market conditions. It will

be suggested in Chapter 6 that the optimal allocation of pesticides from

an individual farmer's point of view might be a fruitful area for future

research.

There are four dominant pesticide formulations used in Dade County-

(1) wettable powder, (2) dust, (3) liquid or emulsifiable concentrate,

and (4) granules-- and there is a range of concentrations available in

each. Parathion, for example, was observed in three different formula-

tions and seven different concentrations.

The technology of pesticide application ranges from the relatively

primitive hand methods to aerial application using helicopters, but most

growers use ground rigs which hold one, two, three, or four hundred gal-

lons of liquid. Aerial application is still slightly more expensive than

ground application; but it is more flexible during adverse weather condi-

tions when ground rigs cannot get into the fields. Some growers claim

that aerial applications are less effective than ground rigs because of

poorer ground and/or plant coverage. The ground rigs are usually operated

at about four miles per hour and three hundred pounds per square inch

nozzle pressure. The number of nozzles varies from three to nine depend-

ing upon the size of plant and desired coverage.

While recommended pesticide dosages are specified on the label in

terms of "amounts per acre," growers tend to make their calculations in











terms of "amounts per one hundred gAilo;i'. odf :.. i:,r" jin'e their spray rigs

hold even multiples of one hundred gallons. "They then try to put the ap-

propriate amount of liquid ( raterr plu.- pretic-.id ')- on r.ar:-ac.re so as not :to

exceed the recommended dosage. ThL ;zray men-are, .for .he mrost -part, lim-

ited in education, so the calculations and .Ti::i:.g are usually done by the

grower, and then the spray man; adjusts :the speed :of. the .tractor .slightly

so that (1) the plants are well covered, and (2) ;a minimum quantity of

spray drops to the ground. In addition, the spray man tries to adjust the

discharge slightly so as to run outn f a:.prI:, about the time he gets to the

side of the field where the pesticides and irrigation ,'ell are located.

In a word, the uniform application of a given quantity of pesticide to an

acre is considerably imprecise.

Aerial spraying is usually done on a contract basis by pilots-who

specialize in crop spraying. The farmer purchases thepesticides and

turns them over to the pilot with a mandate to apply a certain quantity

per acre. The pilot, knowing the size and discharge rate of his spray rig,

then mixes the pesticide with water in-an appropriate ratio to. achieve the

farmer's desired coverage per acre. Boundary lines are fairly well marked,

and experienced pilots familiar with the area can :often spray a field with-

out assistance from the ground. 'Others use a helper -on the ground to mark

off the field boundaries and the spray pro!re:; s. Like spraying with

ground rigs, -aerial spraying is relatively imprecise. Wind conditions can

effect the coverage significantly, and the spray apparatus is difficult to

turn off at exactly the right moment as the pilot turns to make another

sweep of the field. A small survey-of growers and entomologists in the


Relatively little research has been done on pesticide drift. For two
studies see Rollins [50] and Akesson and Yates [2].







2
area, conducted by the Dade County Agricultural Agents Office, indicated

that aerial spraying on the average has increased about 10 to 20 percent

over the past 5 years butt tkat the increase is mainly a function of weather

in the sense that it is becominrp. co m-on for growers to use airplanes after

a rain when it is difficult to get i i.achinery into the fields. Previously,

they simply did not spray until th, fields w-ere dry enough to support the

spray machinery.

The vagaries of weather are also very important in determining the

frequency with which growers must spray. Not only are certain weather

conditions more propitious than others for disease and insect damage, .but

if a grower sprays his field just before a rain he must often spray it

again right after the rain because the pesticide was washed off the plant.

Information on new pesticides and spray programs are disseminated to

the farmer by private firms, the Agricultural Extension Service, and the

State Agricultural Experiment Stations. A sample of this type of Infor-

mation is shown in Tables 8-12. Three points should be noted about the

information in these tables. First, recorfaended control measures change

periodically as new pesticides are developed or as new regulations con-

cerning pesticide usage are passed, Second, the tables do not contain

information on the frequency of pesticide applications. This decision is

made by the grower or his advisor and is a function of many factors such

as degree of infestation, climatic conditions, and so on. Third, as

stated earlier, growers frequently develop their own spray programs for

various insects.


2on by Mr chrd in, f ly rke pe l
Conducted by Mr. Richard Ihiiat, formerly Marketing Specialist.









Table 8.--Alternative recommended insect control measures for tomatoes a


Organic Chlorinated O r Minimum
Other
Insect Pesticide phosphate hydrocarbon days to
quantity quantity quantity harvest

Aphids Dimethoate .334- 7
Demeton .375 3
Parathion .450 3
Phosdrin .500 1
Thiodan 1.000 1
Armyworms, DDT 1.000 3
tomato fruit- Phosdrin .500 1
wdrms, Sevin 1.000 NTL
hornworms TDE (DDD) 1.000 1
Thiodan 1.000 1
**
Loopers Dibrom 2.000 1
Parathion .450 3
Phosdrin .500 1
Thiodan 1.000 1
Leaf miners Diazinon .500 1
Dibrom** 1.000 1
Dimethoate .334 7 ,
Guthion .500 NTL
Stinkbugs, Guthion .500 NTL
other plant Parathion .450 3
bugs Phosdrin .250 1
Sevin '1.000 NTL
Thiodan 1.000 1
Banded cucumber Guthion .500 NTL
beetle Thiodan 1.000 1


a
Source of data: Insect Control Guide [17]
entomologists familiar with the area.
b
Quantities are expressed in pounds of 100
per 100 gallons of water. The gallonage applied
the size and density of the plants. In the Dade
age usually varies from 30 to 125 gallons.

No time limit.
.r* *


and consultation with


percent active material
per acre will vary with
County area the gallon-


Dibrom was not observed in Dade County in 1966-1967.









Table 9.--Alternative recommended insect control measures for pot.


Pesticide


Organic
phosphate
quantity


Chlorinated
hydrocarbon
quantity


Otr Minimum
Other
days to
quantity harst
harvest


Aphids


Armyworms,
loopers, other
caterpillars


Banded cucumber
beetle
Leaf-footed
plant bug,
green stinkbug


Leaf miners




Wireworms


Demeton
Dimethoate
Meta-Systox-R
Thiodan


Parathion
Phosdrin
Thiodan
Toxaphene
Guthion
Thiodan
Guthion
Parathion
Phosdrin
Thiodan
Diazinon
Dibrom**
Dimethoate
Guthion
Thim et
Parathion


.375
.500
.375

.300
.500



.500

.500
.300
.250


.500
1.000
.334
.500
3.000
2.000


21
7
7
1.000 NTL*


1.000
1.000


1.000


5
1
NTL*
NTL*
7
NTL*
7
5
1
NTL*
14
NTL*
7
7


1.000


a Source of data: Insect Control Guide
entomologists familiar with the area.


[17] and consultation with


b Quantities are expressed in pounds of 100 percent active material
100 gallons if water. The gallonage applied per acre will vary with
size and density of the plants. In the Dade County area the gallon-
usually varies from 30 to 125 gallons.

No time limit.

Dibrom was not observed in Dade County in 1966-1967.


Soil treatment prior to planting.


Insect


per
the
age


------------~--~-"------`-








Table 10.--Alternative recommended insect control measures for beans a


Organic Chlorinated Minimum
Insect Pesticide phosphate hydrocarbon ter days to
quaquantb quanquantity harvest


Armyworms,
Corn earworm

Cpwpea curculio

Bean leaf-
hopper, bean
leafrller



Leaf miners,
cucumber
beetles
Thrips
Stinkbugs


Saltmarsh
caterpillar
Lima pod borer


Aphids


.375
.334
.300
.250


1.000

1.000
1.000
.500


Demeton
Dimethoate
Parathion
Phosdrin
DDT
Sevin
Toxaphene
Toxaphene
Thiodan
Dimethoate
Guthion
Parathion
Phosdrin
Sevin
Toxaphene
Diazinon
Dimethoate
Guthion
Parathion
Guthion
Parathion
Phosdrin
Sevin
Phosdrin
Toxaphene
Parathion


1.000


1.000


1,000


21
NTL*
3
1
5
NTL*
5
5
3**
NTL*
7
3
1
NTL*
5
7
NTL*.
7


7
3
1
1.000 NTL*


1,000


Insect Control


entomologist familiar with the area.
b
Quantities are expressed in pounds of 100
per 100 gallons of water. The gallonage applie4
the size and density of the plants. In the Dade
age usually varies from 30 to 125 gallons.

NQ time limit.


Guide [17] and consultation with


percent active material
per acre will vary with
County area the gallon-


Should not apply Thiodan more than 3 times per season.


.334
.500
.300
,500


.500
.334
.500
.225
.500
.300
.250

.500

.300


iSource of data:


-- --- ----








Table ll.--Alternative recommended insect control measures for corn a



Organic Chlorinated Minimum
Insect Pesticide phosphate hydrocarbon e days to
quantity quantity quantity harvest

Aphids, spider Parathion .250 3
mites Phosdrin .250 1
Fall armyworms DDT 1.000' *
and corn ear- Parathion .250 *
worm feeding Toxaphene 1.500 *
in bud Mixture of *
DDT and 1.000
Parathion .125
Mixture of *
DDT and .1.000
Toxaphene .750
Silk-fly Parathion .250 3
Earworms DDT 2.000** *
Sevin 2.000** *
Mixture of *
DDT and 2.000
Sevin .500-
Corn stem DDT 2.000 *
weevil Mixture of *
DDT and 1.000
Toxaphene 1.000
Mixture of *
DDT and 2.000
Toxaphene 1.000


a Source of data
Source of data:


Insect Control


entomologists familiar with the area.


Guide [17] and consultation with


Quantllfitio arr ept lro.rRod in posnri4s oF 100 percent active material
per 100 gallons ot water. The galloiiage applied per acre will vary wiLt
the size and density of the plants. In the Dade County area the gallon-
age usually varies from 30 to 125 gallons.

No specific limitation so long as the usages do not result in a
residue on the edible ears.

These amounts should be mixed in 50 gallons of water and applied
to one acre.










Table 12.--Alternative recommended insect control measures for squash a



Organic Chlorinated r Minimum
Insect Pesticide phosphate hydrocarbon days to
quantity quantity entity harvest

Aphids Parathion .300 3
Phosdrin .250 1
Thiodan .500 NTL
Cucumber Lindane .250 1
beetle, Parathion .300 3
squash bug Phosdrin .250 1
Sevin 1.000
Thiodan 1.000
Leaf miners Guthion .500 *


a Source of data: Insect Control Guide [17] and consultation with
entomologists familiar with the area.


b
Quantities are expressed in pounds of 100
per 100 gallons of water. The gallonage applied
the size and density of the plants. In the Dade
age usually varies from 30 to 125 gallons.


percent active material
per acre will vary with
County area the gallon-


Not registered on squash as of March 15, 1968.








In an effort to delineate a clearer picture of spray programs in

Dade County, Tables 13-17 were developed.3 These tables present alterna-

tive spray programs for the major pests in Dade County, by crop. They

also include the approximate cost per application and an interval esti-

mate of the number of applications needed for a growing season. The data

in these tables, while representing the best knowledge we presently have,

nevertheless must be interpreted and utilized carefully, for they are

very crude and in most cases rest on a priori judgments of those familiar

with the area. Several notes of explanation are needed about the tables.

The alternative controls listed in column 2 represent a list of the

various measures used by the farmers and/or recommended by the experiment

station. The experiment station stated that recommendations for chlor-

inated hydrocarbons have been reduced significantly, and that where an

alternative material is available and effective, it is favored over the

chlorinated hydrocarbons in pesticide recommendations. But since the

farmers are accustomed to using chlorinated hydrocarbons, there may be a

time lag before pesticide usage practices in Dade County are widely af-

fected. Those treatments marked with one asterisk involve a pesticide

which is now on the restricted list (following passage of Florida House

Bill 409) while those marked with a double asterisk are now illegal and

therefore might not be used very extensively.






3
Data in the tables were synthesized from information provided by
scientists in other disciplines from the faculty of the Sub-tropical
Experiment Station (now Agricultural Research and Education Center,
Homestead), and by Professor James E. Brogdon and Mr. Freddie A. Johnson.





Table 13.--Alternative i::nect control programs for tomatoes in Dade County


Alternative controls
Alternative controls


Approximate Approximate range
Approximate of
in number of
cost per
cost per applications
application applications
per crop year

Dollars/acre


*Approximate range
of cost estimates
for pest control
per crop year


Dollars/acre


*(1) :-1 1/2 pts. Demeton 2Ed
(2) :/4-1 pt. Dimethoate 2.67E
*(3) 103 lbs. Parathion 15% WPe
(4) I-2 pts. Phosdrin 2E
*(5) 1 qt. Thiodan 2E plus 1/3-1/2
it. Parathion 8E
(6) L-2 lbs. Thiodan 50% WP


2.56
1.92
.60
2.26

2.05
2.72
2.02


1 2


2.02 4.04


Armyworms,
tomato fruitworms,
hornworms


*(1) 1-3 lbs. Parathion 15% WPf
(2) :-2 pts. Phosdrin 2E
(3) i 1/4 lbs. Sevin 80% WP
*(4) 1 Ibs. TDE(DDD) 50% WP
(5) :-2 lbs. Thiodan 50% WP
**(6) i qts. Toxaphene 4E DDT 2Eg
**(7) 1 qts. Tox 4E DDT 2E -
2arathion lEh
*(8) 1 qt. Thiodan 2E plus 2 Ibs.
?arathion 5% WP
*(9) 1-3 Ibs. Parathion 14% WP plus
1-5 Ibs. Toxaphene 40% WP
*(10) at. Guthion 2E


.60
2.26
.84
(.88)
2.72
(.92)

(1.56)


1-6


1.97


(2.80)
1.52


Average cost 1.65 1.65 9.90

Cutworms *(1) 2 lbs. active Toxaphene per acre 1.00
*(2) 2 lbs. active TDE (DDD) per acre 2.20
(3) 1 1/2 lbs. active Dylox per acre 6.21 1 2
(4) 2 lbs. active Chlordane per acre 2.80
Average costC 3.05 3.05 6.10
Continued


Insect


Aphids






Average cost


-~-"I---I-


----







Table 13.--Alternative insect control programs for tomatoes in Dade County (Continued)

Approxi e Approximate range Approximate range
a pp number of of cost estimates
Insect Alternative controls cost per in numr of
applications for pest control
application
per crop year per crop year

Dollars/acre Dollars/acre
Leaf miners (1) 1-2 lbs. Diazinon 50% WP 4.24
(2) 1 pt. Dibrom 8E 2.20
(3) 3/4-1 pt. Dimethoate 2.67E 1.92
*(4) 2 pts. Guthion 2E 1.52
*(5) 2-3 lbs. Parathion 15% WP .60
Average cost 2.10 2.10 12.60
Stinkbugs, Other *(1) 2 pts. Guthion 2E 1.52
plant bugs *(2) 2-3 lbs. Parathion 15% WP .60
(3) 1 pt. Phosdrin 2E 1.13
(4) 1 1/4 lbs. Sevin 80% WP .84 1 5
(5) 1-2 Ibs. Thiodan 50% WP 2.72
b **(6) 2 qts. Toxaphene 4E DDT 2E (.92)
Average cost 1.36 1.36 6.80
Banded cucumber (1) 2 pts. Guthion 2E 1.52
beetle (2) 1-2 Ibs. Thiodan 50% WP 2.72
(3) 1 qt. Thiodan 2E 1.57 1 5
b **(4) 2 qts. Toxaphene DDT 2E (.92)
Average cost 1.94 1.94 9.70
Loopers (1) 2-3 qts. Bacillus thuringiensisi 6.30
(2) 204 lbs. Bacillus thuringiensis WP 6.30
(3) 2 pts. Dibrom 8E 4.40
*(4) 203 lbs. Parathion 15% WP .60 1 6
(5) 2 pts. Phosdrin 2E 2.26
(6) 2 lbs. Thiodan 50% WP 2.72
Average cost 3.76 3.76 22.56
Continued






Table 13.--Alternative inse:: control programs for tomatoes in Dade County (Concluded)

Approximate range Approximate range
inse a Approximate in number of of cost estimates
Insect alternative controls cost.per applications for pest control
application applications for pest control
application
per crop year per crop year

Dollars/acre Dollars/acre
Wireworms *(1) 1 t. per acre Parathion 8E 1.19
(d:anch)
(2) 10-15 lbs. per acre Thimet 10G3 3.60 only.
Average cost 2.40 2.40 2.40

a Unless otherwise specified, these quantities are to be mixed with 100 gallons of water. On the
average, approximately 80 -llons of the mixture go on one acre.
b Items whose costs ar- in parentheses were not included in the averages.
c Since the only recommended non-chlorinated hydrocarbon for cutworms is Dyiox, a new and relatively
expensive material, we pernrt:ed the other remedies to figure into the average even though they are chlor-
inated hydrocarbons. Cutv:r-as are not usually a great problem, and this would not represent a significant
quantity of chlorinated hy-iocarbon usage.
dThis term indicates :hat there are 2 pounds of pure (100 percent) Demeton dissolved in 1 gallon of
the solvent to form an emulifiable concentrate. The emulsifiable concentrate is in turn mixed and diluted
with water to form the finished emulsion spray that is applied to the crops.
e The term WP means "vittable powder." A WP formulation contains a toxic ingredient, such as para-
thion, blended with an iner: dust. Before applying.to a crop, the formulation is mixed with water.
Only effective if usid regularly.
g Four pounds active ::x:aphene, 2 pounds active.DDT per gallon of emulsifiable concentrate.
Four pounds active ::::aphene, 2 pounds active DDT, 1 pound active parathion per gallon of emulsifi-
able concentrate.
Bacillus thuringientis is a new bacterium which is very specific to worms with little or no apparent
toxicity to humans.
STen percent granular formulation.
Restricted followin-c he passage of Florida House Bill 409.
S_- Banned-fol.ln.. ..L.oL_- -n-c..- -3. .. na- --.-- n-- ---I--------- ^ -_ --.










Table 14.-Alternative in-sct control programs for potatoes in Dade County

ximate Approximate range. Approximate range
Insect Alternative controls cost per in number of of cost estimates
application applications for pest control
application
per crop year. per crop year

Dollars/acre Dollars/acre
Wireworms *(1) 03 Ibs. per acre Thimet 10G plus
3 lbs. active Parathion per acre 10.80
(2) 1 l bs. per acre Thimet 10G 7.20 1 only
*(3) _Ebs. active Parathion per acre 3.60
Average cost 7.20 7.20 7.20
Aphids (1) 1 1/2-2 pts. Meta Systox R 2E 4.59
(2) 1-1 1/2 pts. Dimethoate 2.67E 2.88
(3) 1 pt. Phosdrin 2E 1.13 1 8
*(4) 1 qt. Thiodan 2E plus 1/3-1/2 pt.
Tarathion 8E 2.05
Average cost 2.66 2.66 21.28
Armyworms, loopers,**(l) :-3 qts. Toxaphene 4E DDT 2E (1.38)
other caterpillars (2) 1-2 pts. Phosdrin 2E 2.26
(3) 1 qt. Thiodan 2E 1.57
*(4) 1 qt. Thiodan 2E plus 1/3-1/2 pt. 1 6
Parathion 2.05
b *(5) pt. Parathion 4E .64
Average cost 1.63 1.63 9.78
Banded cucumber *(1) 1 qt. Guthion 2E 1.52
beetle (2) 1 qt. Thiodan 2E 1.57
**(3) 2 qts. Toxaphene 4E DDT 2E (.92) 1 4
(4) 1 pt. Phosdrin 2E 1.13
Average cost 1.41 1.41 5.64
Continued




Table 14.--Alternative insect control programs f r potatoes in Dade County (Concluded)


Approximate Approximate range. Approximate range
Insect Alternative controls cost per innumber of of cost.estimates
application applications for pest control
per crop year per crop year

Dollars/acre Dollars/acre
Leaf-footed plant *(1) 1 qt. Guthior 2E 1.52
bug *(2) 1 pt. Parathion 4E .64
Green stinkbug (3) 1 pt. Phosdrin 2E 1.13 1 2
(4) 1 qt. Thiodan 2E 1.57
Average cost 1.22 1.22 2.44
Leaf miners (1) 1 pt. Dimethoate 2.67E 1.92
*(2) 1 qt. Guthion 2E 1.52
(3) 1/2-1 pt. Diazinon 4E 1.67 1 6
(4) 1 pt. Dibrom 8E 2.20
Average cost 1.83 1.83 10.98

See footnotes d through j to Table 34 for explanations for formulations.

See footnote b of Table 34.

Restricted following the passage of Florida House Bill 409.
** Banned following the passage of Florida House Bill 409.








Table 15.--Alternative insect control programs for pole beans in Dade County

Approximate range .Approximate range
Sroxate in number of of cost estimates
Insect Alternative controls cost per applications for pest control
application
per crop year per crop year

Dollars/acre Dollars/acre
Aphids (1) 1 pt. Diazinon 4E 1.67
*(2) 1 1/2 pts. Demeton 2E 2.56
(3) pt. Dimethoate 2.67E 1.92 0 1
*(4) 1/2 pt. Parathion 4E .51
(5) 1 pt. Phosdrin 2E 1.13
Average cost___ 1.56 0 1.56
Armyworms, corn (1) 1 1/4 Sevin 80% WP .84
earworms *(2) 1 pt. Toxaphene 8E (.34)
**(3) : qts. Toxaphene 4E DDT 2E (.92) -
*(4) 1 qt. Toxaphene 8E plus 1/3-1/2
bt. Parathion 8E (1.14)
Average cost .84 0 .84
Cowpea curculio *(1) 1 pt. Toxaphene 8E (.34)
(2) 1 qt. Thiodan 2E 1.57 0 3
Average costb 1.57 0 4.71
Bean leafhopper, (1) 1 pt. Dimethoate 2.67E 1.92
bean leafroller *(2) 1 pts. Guthion 2E 1.52
*(3) :/2 pt. Parathion 4E .51
(4) 1-2 pts. Phosdrin 2E 2.26
(5) 1 1/4 lbs. Sevin 80% WP .84 0 3
**(6) Z qts. Toxaphene 4E DDT 2E (.92)
*(7) 1 qt. Toxaphene 8E plus 1/3
St. Parathion 8E (.98)
Average costb "1.41 0 4.23
Continued






Tablc 15.--Altarnativ: isn':: control prograsS for pola beans is.n ;Cu=nty (Coztintcd)


Approximate range Approximate range
a Approximate in number of of cost estimates
rnz ie control cost per applications for pest control
application
S per crop year per crop year

Dollars acre Dollars/acre


Leaf miners,
Cucumber beetle


(1)
(2)
*(3)
(4)
**(5)


1/2-1 lbs. Diazinon 50% WP
2 i-1 pt. Dimethoate 2.67E
2 its. Guthion 2E
1 :t. Thiodan 2E
2 4ts. Toxaphene 4E DDT 2E


2.12
1.92
1.52
1.57
(.92)


1-4


Average costD 1.78 .1.78 7.12
Stinkbugs *(1) 2 :ts. Guthion 2E 1.52
*(2) 1;: pt. Parathion 4E .51
(3) 1 -t. Phosdrin 2E 1.13
(4) 1 i/4 lbs. Sevin 80% WP .84 0 3
(5) 1 It. Thiodan 2E 1.57
b**(6) 2 Its. Toxaphene 4E DDT 2E (.92)
Average cost 1.11 iii__0 -- 3.33
Saltmarsh (1) 1-Z pts. Phosdrin 2E 2.26
caterpillar *(2) 1 ?t. Toxaphene 8E (.34) 0 1
b (3) 1 It. Thiodan 2E 1.57
Average cost 1.92" 0 1.92
Wireworms *(1) 1 qt. per acre Parathion 8E
(-ench) 1.19
(2) 1:-15 lbs. per acre Thimet 10G 3.60 0 1
Average cost .2.40 0 2.40
Continued


Insect







Table 15.--Alternative in;~:t control programs for pole beans in Dade County (Coacluded)


Alternative controls


Approximate
cost per
application


Dollars/acre


Approximate range
in number of
applications
per crop year


Approximate range
of cost estimates
for pest control
per crop year


Dollars/acre


Lesser cornstalk
'borer


*(1) l Ibs. per acre Parathion
5% VWP


.60


0-2


Average cost .60 0 1.20

a Se footnotes d though j to Table 34 for explanation of formulations.

b
See footnote b of "?ble 34.

* Restricted followir7 the passage of Florida House Bill 409.


** Banned following net passage of Florida .House Bill 409.


Insect






Table 16.--Alternative ins-t:: control programs for sweet corn in Dade County

Approximate range Approximate range
Approximate
Insect ternatv a r e in number of of cost estimates
Insect Alternative controls cost per applications for pest control
apito applications for pest control
application
per crop year per crop year

Dollars/acre Dollars/acre
Wireworms *(1) 3 Ibs. active Parathion per acre
1 :o 2 weeks before planting
pi::s 30 Ibs. per acre Thimet 10G
at planting 10.80 1 only
(2) 3_ Ibs. per acre Thimet 10G 7.20
Average cost 9.00 9.00- 9.00
Fall armyworms, (1) 1-1 1/3 Ibs. Gardona 75% WP 2.92
corn earworms *(2) 1,Z pt. Parathion 4E plus 1 1/2
feeding in bud, pas. Toxaphene 8E (.83) 8 14
aphids *(3) 1., pt. Parathion 6E Methyl
b prathion 3E .40
Average cost 1.66 13.28 23.24
Earworms (1) 2,3 1 lb. Gardona 75% WPd 2.20
*(2) 1,2 pt. Parathion plus 4 qts.
DLT 2Ed (2.10)
*(3) !,l.pt. Parathion 6E Methyl
p-rathion 3Ed .40
(4) 2 1/2 lbs. Sevin 80% WPd 2.10 10 18
*(5) 2 its. Toxaphene 4E DDT 2Ed (1.15)
*(6) 4 its. DDT 2Ed (1.70)
*(7) 3 i 1 qt. Toxaphene 8Ed (.83)
S*(8) 13 pt. Parathion 8Ed .40
Average cost 1.28 12.80 23.04
Continued










Table 16,--Alternative insect control programs for sweet corn in Dade County (Concluded)


Alternative controls


Approximate
cost per
application

Dollars/acre


Approximate range .Approximate range
in number of of cost estimates
applications for pest control
per crop year per crop year

Dollars/acre


Cutworms



Average cost


*(1) Toxaphene 2 Ibs. active
*(2) TDE (DDD) 2 lbs. active
(3) Chlordane .2 bs. active
(4) Dylox 1 1/2 lbs. active


per acre
per acre
per acre
per acre


2.20
2.20
2.80
6.21
3.35


0-1


0 3.35


a See footnotes d through j to Table 34 for explanation of formulations.

See footnote b, Table 34.

C See footnote c, Table 34.

These amounts should be mixed into 50 gallons and applied to one acre.

* Restricted following the passage of Florida House Bill 409.


Insect


--~- L--C----LI-------- -- _~_~_ -----~.-f--l*--_-------.-----






Table 17.--Alternative inrsct control programs for squash in Dade County

Approximate range Approximate range
Approximate
Insect Alternative controls cost per in number of of cost estimates
application applications for pest control
per crop year per crop year

Dollars/acre Dollars/acre
Leaf miners (1) 1/4-1 pt. Dimethoate 2.67E 1.92
*(2) : pts. Guthion 2E 1.52 1 6
Average cost 1.72 1.72 10.32
Aphids (1) :/4-1 pt. Dimethoate 2.67 E 1.92
*(2) -/2 pt. Parathion 4E .32
(3) pt. Phosdrin 2E 1.13
(4) i qt. Thiodan 2E 1.57
*(5) 1 Ibs. Parathion 14% WP plus
1 qt. Thiodan 2E 1.97
(6) lIb. Lindane 25% WP .96
Average cost 1.31 1.31 7.86
Cucumber beetles, *(1) :/2 pt. Parathion 4E .32
belonworm, (2) : pt. Phosdrin 2E 1.13
pickleworm, (3) 1 1/4 lbs. Sevin 80% WP .84 1 6
squashbug (4) I qts. Thiodan 2E 3.14
Average cost 1.36 1.36 8.16
Cutworms *(l) 1 Ibs. active.Toxaphene per acre 2.20
**(2) 1 Ibs. active TDE (DDD) per acre 2.20
(3) i Ibs. active Chlordane per acre 2.80 1 only
b (4) L 1/2 Ibs. active Dylox per acre 6.21
Average cost 3.35 3.35 3.35


aSee footnotes d th:rugh j to Table 34 for
b
See footnote c, Toie 34.


explanation of formulations.


* Restricted follow-vi the passage of Florida House Bill 409.
** TDE may be used ori7 for soil treatment on squash.








For many of the materials, a dust formulation also exists. These

have not been included since they are the same basic material and are

usually similar in cost per pound of technical material.

The alternative controls shown in column 2 are not perfect substi-

tutes. At one point in time a farmer might be able to control the aphids

on his tomatoes with parathion 15 percent wettable powder, a very cheap

material. But at some other time he might have to use a much more expen-

sive material such as Phosdrin or Thiodan. The farmers themselves have

no particular rules of thumb in this matter. Most of them simply utilize

different materials until they find one (or several in combination) that

is effective in the given situation. Further study, perhaps controlled

experimentation, might clarify the relationships and help to identify which

pesticides are best in alternative situations. Such study is badly needed.

Column 4 shows interval estimates of the number of applications nec-

essary to control the given insect. These interval estimates are thought

to be wide enough to account for the fact that the alternative controls

are not perfect substitutes, for the possibility of eliminating most of

the chlorinated hydrocarbons which is required for Policy 3, and for vary-

ing insect infestations which have been experienced in the past. If per-

sistent materials were denied to the farmers, the number of applications

would tend toward the higher end of the indicated range, and hence the

cost would also tend toward the higher end of its range. Cost estimates

are simple averages of costs of selected treatments for a given insect

multiplied by the indicated number of applications.

A further limitation of these tables is the fact that controls for

different insects are not independent. Thus, spraying for aphids on









tomatoes may reduce the:threat from armyworms, and vice versa. Those

whose judgments fornmd the basis for these tables tried to take this phen-

omenon into account in estimating the number of applications-for column 4.

While these tables provide a broad picture of the recommended controls

for different pesticides and the possible frequency of spraying, more pre-

cise estimates of the usage of chlorinated hydrocarbons and organic phos-

phates were needed to estimate the externality function for the model.


Estimating the Quantities of Pesticides Used in Dade Councy

One might go about estimating Dade County's agricultural usage of

pesticides in several ways. The quickest would be to assume that growers

-follow labeled recommendations, and to calculate an estimated usage based

on an assumed frequency of application, an assumed length of growing sea-

son, and a knowledge of the acreage of each crop.

For this study, however, the quantity of pesticides used for agricul-

ture in Dade County was estimated by interviewing the growers and by using

records of the growers' pesticide purchases. The growers which were inter-

viewed accounted for the following proportions of harvested acreage in

1966-1967:

Tomatoes 73.5%
Potatoes 72.5
Pole beans 65.0
Corn 96.5
Squash 29.2
Other vegetablesa 43.8
Total vegetables 59.0
Groves 12.6

a Includes okra, peas, cucumbers, cuban pumpkins.

Includes avocados, limes, mangos, papayas.







In some cases the growers kept individual field records which were made

available.

When a pesticide firm makes a sale to a farmer, an invoice is pre-

pared in triplicate. The farmer receives one copy and the firm keeps

two. At the end of the month when statements are sent out, another copy

is sent to the farmer along with his bill. The farmers usually keep

this second one for their records. During the interviews the farmers

were asked for permission to copy these records or to copy the originals

from their pesticide suppliers. If the farmer preferred that the data

be obtained from his pesticide supplier, he was asked to sign a permission

statement for the protection of the supplier. After making preliminary

visits to the suppliers to explain the research, they were approached and

asked to cooperate. Of the eight major firms in the area, six agreed to

let copies be made of invoices of sales to customers who had given permis-

sion to do so. Two refused to cooperate so their information was obtained

from the grower's copy of the invoice.

As noted previously, there were many different pesticides used in

Dade County, and most of the pesticides were used in a number of different

formulations. Initially, there were 212 separate pesticides and formula-

tions identified. For a given pesticide the different formulations were

conveLrted lo ilit-s f r i1f p i c r t-iL UOtIo nei l li aLeld ,mai.ei .aL t alld tlr1l L1yel.lther.

This reduced the number of pesticides to 56.4

The basic unit of observation for all of the pesticide usage tables

was either a grower or a field. Where a grower had complete spray infor-

mation:on his fields, each field was considered a separate observation.


The common name, trade name, and/or chemical name of these are
available from W. F. Edwards or M. R. Langham.










If he did-not keep field data, the farmer was asked to designate what

crop every pesticide invoice was used on, and it was assumed that the

pesticide was used uniformly on all his land planted in that crop. It

was further assumed that the pesticide was used in the month in which it

was sold.

It was not particularly difficult for the farmers to match the pesti-

cide with the crop on which it was used since (1) the crops tend to differ

in their basic spray programs both as to ingredients and timing, and (2)

most of the farmers tend to specialize in certain crops. Many of those

interviewed grew only one crop and very few grew more than three. Justi-

fication for the assumption that the pesticide was used in the month in

which it was purchased is found in that fact that many growers stated they

were unwilling to tie up capital and warehouse space maintaining an inven-

tory of pesticides which were dangerous and might, in some cases, spoil

before being used. Transportation and labor costs were also saved since

the pesticide supplier would deliver directly to the field where the pest-

icide was needed.

The crop year for the pesticide usage estimates extended from July

until ,the following June. Most of the planting was done in September,

October, November, and December, and most of the harvesting in January,

February, March, and April.

Table 18 is a pesticide usage profile for Dade County for the organ-

ic phosphates and the chlorinated hydrocarbons, by crop. These are the

estimates needed for the model. Some of the figures are rather striking.

Corn, for example, used a very high level of chlorinated hydrocarbons.

This was because farmers dusted their sweet corn almost daily to avoid


corn ear worm.







Table 18.--Estimated average quantitiesa per acre of organic phosphates,
chlorinated hydrocarbons, and total pesticides used by farmers
in Dade County, 1966-1967 crop year, by crop b



Organic Chlorinated Total All
phosphates hydrocarbons Pesticides

Tomatoes 3.27 6.07 37.40

Potatoes 5.89 1.29 32.53

Pole beans 1.81 3.43 66.90

Corn 6.46 40.70 63.88

Squash 1.03 2.60 47.33

Okra 3.25 5.00 43.69

Groves .44 .14 35.18

Other .22 4.92 13.42

Total average usage 3.57 5.03 38.76


a
aAll quantities have
concentrated material.
b
Acres sampled and ni



Tomatoes
Potatoes
Pole beans


Squash
Okra
Groves
Other


been converted


to pounds of 100 percent


umber of observations were:

Acres Observations

10,590 24
4,584 51
2,394 93


244 11
50 2
1,247 26
240 2


- *-. ri~ .''-. -,-,-. .- *-r- -.-*, -- <'/,-* ^-- .-. *-(-: "t;S* itep,; u;5' -ii %j;^ *'*-*









On the average, there were about 3.5 pounds of organic phosphates

applied per acre in Dade County as compared with pounds of chlorinated

hydrocarbons. Although it is not shown in the table, recent data seem

to indicate that the usage of organic phosphates is increasing while that

of chlorinated hydrocarbons is falling.

The last column of the table shows estimates bf the total amounts of

all pesticides used per acre, by crop.5




































5Estimates broken down by crop, pesticide, and month of usage are
available from the authors.














CHAPTER 5

PESTICIDES AND EXTERNALITIES


The objective of this chapter is twofold--first to provide the basis

for the point estimate of externalities needed for the model and second

to describe in somewhat more general terms the current state of knowledge

about pesticide effects upon wildlife.

For purposes of empirical measurement an externality was defined as

any "cost" which was created by the agricultural use of pesticides but

was not borne, or was only partially borne, by the producers. This defin-

ition does not preclude the possibility of handling an external benefit

as a negative cost. It is empirically operational and is not inconsistent

with that presented by Buchanan and Stubblebine [11].


Externalities in Dade County

Although the estimation of externalities in Dade County was primarily

based on information from two main sources, a total of five were utilized

in an effort to be as comprehensive as possible.

1. The Grower Interview. A section of the grower questionnaire was

devoted to such questions as human sickness and damage to wildlife and



Most of the growers in Dade County have had some experience with

pesticide sickness. The responses of the growers indicated that such in-

cidents were not increasing and most likely were decreasing in spite of



A copy of the questionnaire is available from the authors.
i" ,

I/ : '









growing organic phosphate usage. Growers stated that education of spray

men to the dangers of pesticides and the safe ways of handling them has

been a key factor in checking the rise of such incidents. It should be

stressed that "safe ways of handling them" did not always coincide with

"recommended ways." Only one grower stated that he required his men to

wear protective clothing such as boots, gloves, and masks while spraying.

The rest of the growers indicated that they made such equipment available

but could not get their spray men to use it. This equipment is very un-

comfortable in the hot climate of South Florida, and most of the spray

men would simply prefer to "take their chances" with the pesticides. In-

dividual tolerance to pesticides among spray men seemed to vary a great

deal. Some spray men were able to work with pesticides without ill ef-

fects while other spray men tended to be very sensitive to them. In gen-

eral, sensitive spray men did not remain spray men very long. This

"natural selection" process is also a possible explanation for the fact

that pesticide sickness does not appear to be on the increase. It was

also reported that some spray men refuse to apply the highly toxic organ-

ic phosphates such as parathion. This was not observed to be very wide-

spread, however. (Table 19 summarizes the responses of the growers to

questions concerning human sickness.)

Grower responses to questions about damage to domestic animals and

wildlife were somewhat vague as to time of occurrence and extent of damage.

In most cases this was probably due to lack of recollection. Many of the

growers acknowledged fish-kills in the canals. Water was frequently taken

out of the canals for irrigation and for mixing with pesticides. Some of

this water eventually seeped back into the surface and ground waters,




: er responses concerning um n sick ess from pesticides


Pesticide


Date Time in hospital


Comments


1 Parathion



2 Parathion



3 Parathion


5 Parathion


6 Dyrene



7 Parathion


Parathion
Thimet


1962



1958


1964 2 or 3 days


1964 Approximately
1 week


1959
1966


About 2 weeks


The grower reported .that through the years he had built up
a sensitivity to Parathion and could no longer come in
close contact with it.
Grower reported that his brother was careless while spray-
ing in the yard and got some Parathion on his skin, making
him ill.
Grower became sick from Parathion while spraying a tree in
his yard. He was using a hand sprayer and the chemical
drifted down on him.
Grower reported that his workers had considerable trouble
with dermatitis while picking tomatoes; however, the cause
was uncertain and could be due to the stem fuzz as well as
pesticides.
Grower reported that his Mexican foreman, on:a very hot day,
accidently got Parathion on his skin.
Grower reported that-his men have had some problems with
dermatitis from Dyrene. When this happens he does not allow
the man to spray any more.


Man was spraying corn and got in the diift. He was not
wearing a mask.
No detail in this case.
Grower goet sick in spite of fact that he had on gloves and
mask. He went to the Poison Control Center and tests came
back negative but he still felt that it was the Thimet, and
he could no longer get near the material


Continued


Case
number


_ ___I_


_ -L-. r ---n.~--I--L-


a, e .-- s ary









Case Pesticide Date Time in hospital
number


1960 2 weeks


1964


12 Phosdrin 1961 1 night in
hospital for
each instance


13 Parathion


14 Parathion


1964


1966 3 days


15 Paration 1965 1 day


16 Parathion


17 Parathion
18 Parathion


1967


1963 1 week
1965 1 week


10 Parathion


Continued


Spray man absorbed the pesticide through his skin. He al-
most died in the hospital and thereafter was not able to
use Parathion. In addition to the time spent in the hos-
pital, he was off work at least a month.
Three men were involved in this instance. They were
spraying Parathion without face masks. About 2 hours per
man were lost from work while a doctor examined them.
These two instances involved the same man. Each instance
involved skin absorption. After the second instance, the
grower quit using Phosdrin.
Spray man was not using any protective clothing and appar-
ently got some Parathion on his skin. He has had no fur-
ther trouble since then.
Spray man did not wash his hands before eating lunch. He
never reported back to work after release from the hospital.
Grower reported he did not know where he had gone.
Grower reported that the employee had been discing new land
and that there had been no opportunity.for contact with
Parathion while on the job. Nevertheless the hospital
diagnosed it as Parathion poisoning.
Grower reported that employee sprayed with Parathion on
Friday but did not get sick until Sunday. Doctor's diag-
nosis was Parathion poisoning.
No details.
Spray man was careless during a drenching operation. He
worked all day with a fine mist blowing on his left leg.


11 Parathion


Comments


-cii.ay: "-, -*--r oncer--n -n -. 4 -,,--.4- A-




a .e ..


Case Pesticide Date Time in hospital Comments
number


19 Parathion


1964 About 2 days


20 Phosdrin 1960


21 Parathion

22 Parathion


23 Parathion


1966

1963



1965


Instead of walking around the spray rig to check the nozzles,
this spray man ran through the mist.
Grower himself got Phosdrin poisoning and had to get hourly
shots at the hospital for several days.
Grower got a slight touch of Parathion sickness. Doctor
prescribed some pills which he took for several days.
Spray man was putting water into a can of Paratior with a
hose. He withdrew the hose from the can and took a drink of
water, allowing the hose to touch his lips.


Grower's 17-year-old son spilled
of the strongest concentrations,
stripped him.immediately, washed
then set him home to bathe again.


"8E liquid Parathion," one
on his leg. The grower
him from the waist down,
No problems developed.


24 Thimet





25 Parathion




26 Parathion


1966


Grower reported that Thimet was used on corn or potatoes
very close to his home, and it caused his wife and several
neighbors to become ill. It caused nausea, headache, and
loss of equilibrium. Grower stated that the proximity of
the usage to his home was in violation of recommendations.


Grower reported that over a 20-year period he.had 8 or 10
.men to get sick from Parathion. The last incident was in
approximately 1960. In no cases did anyone lose more than
a day or two from work.
1963 "A number of days" Grower reported that spray man absorbed Parathiil; through
his skin. He never allowed the man to spray again.









carrying with it some pesticide residues. It was also likely that some

residues in the surface waters flowed down from the farming regions just

north of Dade County. Growers also acknowledged thatspray rigs were

frequently washed out in the canals, increasing the pesticide residues.

Most of the fish found in the canals and drainage ditches are what con-

servationists call "rough fish" (not considered suitable for human con-

sumption), but the migratory laborers, nevertheless, ate them, and they

were a part of the ecological system of the area.

Some wildlife could of course be classified as "pests" and were

purposely poisoned by the growers. This was frequently the case with

rats, blackbirds, crows, and raccoons. One grower indicated that the

robin was a pest to strawberry growers. Seagulls are very plentiful in

the area, and several growers said that they were sometimes killed by

the pesticides. Three growers stated that they had one dog each killed

from drinking polluted water standing in the fields.

It is' customary in Dade County to use honeybees to facillitate pol-

lination of some of the blooming crops. Squash is the dominant example.

Hives of honeybees are rented from beekeepers by the growers and placed

around the field. One beekeeper, a past president of the Beekeeper's

Association, was contacted about pesticide damage to the bees. He stated

that such damage was very common and that most beekeepers assumed that

they would lose a few bees when they were rented out. Bees, however,

reproduce very quickly, therefore the economic loss was slight. He fur-

ther said that most of the growers were using more caution, and that dam-

age during the past two or three years was much less than it had been

previously. Generally there was no cash settlement above rental cost when










damage occurred.

Damage among'growers from pesticide drift was also investigated.

When such damage occurred the growers usually settled the problem infor-

mally among themselves with the damaging party "paying off" in one form

or another. Sometimes the party causing the damage was unknown and the

damaged party simply had to absorb the cost. In either case, the costs

were limited to the producers as a group and were not construed as being

external to the industry supply function. The trends toward fewer crops

and larger crop fields have caused the drift problem to decline in recent

years.

It is conceivable that external benefits may have existed due.to

pesticide drift. One grower located in the center of a number of growers

who spray regularly may not have to spray as much as he would otherwise

because of the drift from the other growers and the protective pesticide

barrier around his field. This is speculation, however, and we were un-

able to gather any data to substantiate such a hypothesis. (Table 20 is

a summary of the drift problem as reported by the growers.) i

As a group, the growers were well insured. Not only did almost all

of them carry workmen's compensation on their employees, but they also

carried general liability insurance to protect themselves in case.they

damaged the property of others. They did not, however, have insurance i

for cases where others damaged their property. I

2. Insurance Claims. A Florida State law requires all workmen's

compensation claims to be on file with the Florida Industrial Commission.

Industrial Commission data for Dade County for the years 1966 and 1967

.were obtained and summarized.








Table 20.--A summary of go-wer responses concerning damage from pesticide drift

Case
nuse Pesticide Date Crop Extent of damage Comments
number


I Amine 2, 4-D


1955 Tomatoes slight


Pctatc grc:ar vac the damaging party.
was no settlement.


2 Sodium Arsenite

3 Not available



4 Not available

5 Not available


6 Not available






7 Sodium Arsenite


1961 Beans

1958 Tomatoes


1957
r 1958


Beans


Not available

Not available


10 acres


1958 Tomatoes 10 to 20
acres

1967 Groves


1965 Beans


8 Not available Not Tomatoes
Saxailable


About $300

10 acres


Potato grower was the damaging party. A
settlement was made.
Aa zirplzarz .3 i spraying defoliant on soybeans.
A small payment was made and lost materials,
such as fertilizer, were replaced.
Potato grower was the damaging party. A small
settlement was made.
This is the same incident as #3 above--several
growers were damaged by the defoliant. No
settlement was made.
The Seaboard Railroad sprayed their right-of-
way for weed control, and it damaged this
grower's trees. However, it turned out that
the trees were on the right-of-way so the
grower agreed not to file suit if the railroad
would not destroy the trees.


Potato grower was the damaging party.
ment was made by an insurance company.


Settle-


Grower reported that the county damaged these
tomatoes with an herbicide. No settlement was
made.


Sodium Arsenite 1959 Beans


Toxaphene


Not Squash
available


Slight
Not available


Potato grower. No settlement was made.
Grower damaged his own squash crop while treat-
ing his bean crop.


Continued


There





Table 20.--A summary of grZwer responses concerning damage from pesticide drift (Continued)


Case Pesticide late Crop Extent of damage Comments
number


11 Parathion


vadt
available


None


Not available


A dusting pilot's hopper hung up and
dently dusted some of the government
around the Homestead Air Force Base.
grower received a "cease and desist"
from Washington ordering him to quit
so near the base.


the acci-
houses
The
letter
farming


12 Sodium Arsenite


13 Atrazine


14 Sodium Arsenite
15 Sodium Arsenite

16 Amine 2, 4-D


17 Amine 2, 4-D


18 Sodium Arsenite


E364 Beans and
tomatoes


1963


Beans


-65 Cron


1266 Tomatoes


__66 Tomatoes


2357
or 1958


Tomatoes


Not available


$1000
Slight


80 acres
amounting to
$24,000
About 50% of
60 acres was
destroyed
4 acres
amounting
to $300


Grower reported that he has occasional small
incidents from potato vine killer. He said it
could .not be avoided, and when the damage is
great enough he settles with the grower invol-
ved.
Corn growers paid off the bean and tomato
growers.
Potato grower was the damaging party.
Potato grower was the damaging party. No set-
tlement was made.
The grower could not find out who had done it.
Scientists from the University of Florida
investigated. No settlement was made.
This was the same situation as #16 above.


Potato grower was the damaging party. No set-
tlement was made.


Continued.








Tble 2 .--* .A ma-r F rGespner rsOn concerning d f-rom T ci-ri-ie Ari-ft (Cornnnl1itrl)
-- ------ ---- ---- ------ --- - ------ -.; j--- *tJ- __-- __


Case
Case P ticide 2~-t Crop
number


Extent cf darage


amounting to
about $1200

5 tc 10%
reduction irn
yield on about
5 acres


damaging party was not disclosed.


------c- ---=:z-2
from ths Air Fcrce, but the "rd tape got so
involved" that he decided to drop it.


14
anJ ri l--


cr 1963


_______I ___I_ ~~-L-l---l.l I_


- -- .--II I---------------LU---- -









All of the workmen's compensation claims reported to the Industrial

Commission are classified into two groups--disabling and non-disabling.

These terms are defined as follows:

Disabling injury: a work injury resulting in death, permanent
impairment, or loss of time beyond the day or shift of occurrence.

Non-disabling injury: an injury arising out of and in the
course of employment in which there is no loss of time beyond the
day or shift of occurrence [19, 1966 edition].

Very little data are maintained on the non-disabling category. The num-

ber of injuries in this category is much greater than for the disabling

category, but the cost involved is much less.

The Industrial Commission categorizes its disabling injuries in a

number of ways. The one which seemed most important for this research-

was "disabling work injuries by agency." The "agency of injury" indenti-

fies the object, substance, exposure or bodily motion which directly pro-

duced or inflicted the injury [19, 1966 edition]. There are 53 agency

categories, one of which (Agency 10) is called "poisons and infectious

agents." The magnitude of this category relative to total state workmen's

compensation claims is shown in Table 21. For the State as a whole the

category "poisons and infectious agents" is declining in importance, as

indicated in Table 21. Number of injuries, days lost, and cost have all

,Pl~(trled por,,,ta-pPwie since 1962, The Dade County cost figures for

1966 and 1967, shown in Table 22 are consistent with this finding. In

1966 the total cost for the agency was $175,497 while in 1967 it was

$116,450.

The Southern Farm Bureau was the dominant agricultural insurer .in

the area and readily agreed to cooperate on the project. The following

conclusions were drawn from visits with representatives of the company.







Table 21.--Torkmen's compensation claims, State of Florida; work injuries, days of disability,
and cost by agency, for disabling work injuries, 1962, 1963, 1966, and 1967a


.Number of
injuriesDays lost
injuries


Cost


1962
State total
Poisons and
Percent
1963
State total
Poisons and
Percent
1966
State total
Poisons and
Percent
1967
State total
Poisons and
Percent


fectious agents
infectious agents


infectious agents


infectious agentsb


infectious agents


56,701
2,082
.036


51,297
1,747
.033


80,803
2,622
.032


71,490
2,339
.033


4,274,398
89,197
.0208


4,517,191
69,919
.0154


7,704,996
126,298
.0164


6,258,464
77,139
.0123


$25,713,086
516,380
.0200


28,497,999
517,730
.0181


51,599,084
831,477
.0161


43,115,224
665,473
.0154


a Source: [19].

b
This agency includes 53 subcategories, five of
five are: 1) Dieldrin; 2) Insecticides not elsewhere
5) Chemicals and poisons not elsewhere classified.


which could contain pesticide damage. These
classified; 3) Malathion; 4) Parathion; and


_I_~_~_
__






Table 22.--Dollar costs of disabling workmen's compensation claims for Dadit County.
Florida, 1966 and 1967, by kind of payment and selected agents"


.Kind of payment

1 2 3 4 5 6


Total


7 8


1966
Insecticide, n.e.c.
Parathionc
Chemicals and poisons
n.e.c.
All other agents

Total all agents

1967
Insecticide, n.e.c.
Parathionc
Chemicals and poisons
n.e.c.
All other agents

Total all agents


$ 872
87

22,574
60,438

$83,971


$ 806
77

11,903
S32,077

$44,863


$ 547 $ 495
0 167


14,165
35.693

$50,405


8,863
25,329

$34,854


$ 0
728

3,457
8,761

$12,946


$ 653
0

4,701
7,619

$12,973


$ 60
0

874
2,123

$3,057


$ 27
0

569
1,859

$2,455


$ 0
0

0
500

$500


$ 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

6,165
23,995

$30,160


$ 1,738
892

44,973
127,894

$175,497


$ 125 $ 1,847
0 167


4,607
11,031

$15,763


32,905
81,531

$116,450


S ource of data: computer tapes supplied by the Florida
agents include only those that could contain pesticide damage.


Kind of payment is coded as follows: Code
S1
Not elsewhere classified. 2
3
4
5
6
7
8


Industrial olnmmissloa." The selected


Kind of Payment
Compensation
Medical
Hospital
Aritficial members
Burial
Child labor penalty
Attorney fees
First aid









1. Property damage claims from pesticides would be negligible rela-

tive to workmen's compensation claims from pesticides.

2. The number of pesticide claims in Dade County has probably in-

creased in recent years but not as fast as the increase in use of organic

phosphates. Farmers in Dade County are using more caution than previously.

3. Dade County probably has a smaller amount'of pesticide damage

than other areas of the State because its agricultural industry does not

have such a high turnover of farmers and laborers, and the farmers as a

group are relatively sophisticated.

4. In setting premiums, the fact that a farmer does or does not use

pesticides is not considered. The Farm Bureau uses a "whole risk" con-

cept. This provides an interesting hypothesis about the behavior of in-

surance companies. With regard to a farmer or a region there might be

a "sensitivity threshold" which must be broken before a response is gen-

erated on the part of the insurance company. This "sensitivity threshold"

could be visualized as follows:




0. --- Sensitivity threshold


4 0
0

Time

When the dollar claims break the sensitivity threshold, the insurance

company responds by raising rates, cancelling policies, or some other

action. If the dollar claims are defined to be the marginal claims due

to pesticides, then external costs are imposed on the insurance company

until the threshold is broken and the situation adjusted by an increase.









in premiums or other appropriate response. No empirical work was done to

try to substantiate or refute this hypothesis.

3. Veterinarians. In order to get additional information on the

effects of pesticides on domestic animals, arrangements were made to sam-

pie the records of three veterinarians in the area. Two were located

approximately on the dividing line between the rural and urban areas,

while the third was located in Homestead, the heart of the rural area.

Samples which were as nearly random as possible were taken from each.

The frequency of pesticide calls was noted along with the diagnosis, the

species, and the treatment. After sampling, a brief conversation was

held with each veterinarian to see if the sample bore out his.a priori

notions. The veterinarians all stated before seeing the sample results

that they would expect the frequency of pesticide cases to be a small

fraction of one percent. They further said that they felt the incidence

of pesticide calls was not increasing. A summary of the sampling experi-

ence is shown in Table 23.

The reason for including toad and lizard poisonings was that their

symptoms are very similar to those of pesticide poisoning, and a

2
The first veterinarian numbered his cases sequentially and had about
10,000 of them. Each case contained an average of 4.5 calls. Using a table
of random numbers to determine the starting point, 909 cases were examined i
for a total of 4,090 calls. There was no relation between a case's sequence
number and the dates of the calls contained therein.
The second veterinarian maintained his cases alphabetically, by last
name ofowner, and did not know how many he had. There were 10 small file
drawers involved so the first and last 150 calls in each drawer was arbi-
trarily examined. This veterinarian also kept a separate file for de-
ceased cases, and all of these were examined. !
The third veterinarian maintained his files alphabetically, by last
name of owner, and they did not lend themselves well to sampling. For this
veterinarian, all of the "D's" were examined--a total of 275 cases with 4
calls per case.







Table 23.--A summary of data gathered from veterinarians in Dade County


Veterinarian 1


Total number of calls examined 4090

Number of calls due to pesticide 4b
poisoning

Number of calls due to toad or


Veterinarian 2

Deceased file Live file


2082
9c


3500

0


Veterinarian 3a


1100

4d


lizard poisoning 5 5 15e 0

Total calls due to poisoning 9 14 15 4

Proportion poisoned .0022 .0067 .0043 .0036


a The files of this veterinarian had been purged of all the animals that died; he did not keep
a deceased file.

One dog ate roach poison; a second was questionable as to the diagnosis.

c
COne dog ate ant poison; two more were questionable; a fourth had no diagnosis but was treated
with atropine, a standard antidote for poison or shock.

One of these was questionable as to diagnosis.

e One of these was a pet mountain lion poisoned by a lizard.









veterinarian sometimes cannot tell the difference. As is indicated by

the footnote to the table, an effort was made to include all calls which

might have been connected with pesticides even though some were question-

able. Even so, the frequency of pesticide calls was extremely low and

was far overshadowed by:

a. cases where animals were hit by autos,

b. cases where an animal swallowed a fishhook,

c. cases of tick paralysis,

d. cases of dog fights or cat fights.

4. Biologists. The following items represent a few of the many

hypotheses about pesticides and how they can affect life forms. Some of

them (such as 1, 2, and 4) are widely accepted. Others are supported by

little evidence and require more substantiation.

1. Because of their relatively slow biological degradation,
the chlorinated hydrocarbons tend to disseminate easily and widely
throughout the environment.

2. The phenomenon of "biological magnification" contributes
to the dissemination of persistent pesticides through the environ-
ment. Biological magnification is the term used to describe the
tendency for a predator to accumulate higher concentrations of
pesticide residues than its prey (and for certain elements of the.
environment such as mud and sediment to accumulate relatively high
concentrations). However, the relationship between this tendency
and the next hypothesis is not well understood.

3. It appears to be a general rule that the chlorinated hy-
drocarbons are lost from the body after they are removed from the
diet (in both man and animals), suggesting that equilibrium levels
would be obtained in long term studies [64, p. 10].

4. A pesticide may have widely varying effects from one
species to another and even from one individual to another within
the same species. Also, two pesticides, evdn though they come
from the same chemical family, might have greatly different ef-
fects upon a given individual or species. These characteristics
have severely complicated research on pesticides and wildlife.









5. In laboratory studies the heavy, healthy animals tend to
live longest under dosage. Presumably, the heavy animals store
the pesticide in fat, isolating it from vital organs. If this is
true, it suggests that when the animals lose weight the pesticides
might be metabolized. This could have profound ramifications for
wild animals that fall into stressful situations such as limited
food supplies or extremely cold weather.

6. Some evidence indicates that certain species of vertebrates
may be developing a resistance to chlorinated hydrocarbon pesticides.
If this hypothesis is generally true, for all species, it would
change the whole complexion of the pesticide issue [22, pp. 877-878;
34; 46, pp. 1009-1010; 69].

7. Evidence is accumulating that long-term exposure to sub-
lethal levels of certain pesticides has detrimental effects on the
reproductive processes of birds. One hypothesis is that "the phen-
omena of thin egg shells and egg-breakage are explained on the
basis of inhibition of carbonic anhydrase" [47, pp. 592-594]. "The
limitation by carbonic anhydrase of carbonate ions needed for the
deposition of the calcium carbonate of the shell could provide the
mechanism by which chlorinated hydrocarbons affect eggshell thick-
ness" [6, pp. 594-595]. Evidence is strong that certain pesticides
may also be detrimental to reproduction in fish [44; 5].

The hypotheses in the proceeding list illustrate that all is not

"sweetness and light" when it comes to pesticide usage. In short, the

use of pesticies, while creating great benefits in the production of food

and reduction of disease, may also create social costs of uncertain mag-

nitude. Many argue that the potential magnitude of these social costs is

large enough to justify public action to limit pesticide use. The pesti-

cide issue is certainly not as "clear-cut" as it seemed about 15 years

ago before the awareness of the possible social costs.

Biologists at the Everglades National Park and the research director

for the National Audubon Society, located at Tavernier Key, were contacted

in an effort to gather more specific information on pesticide damage to

wildlife in Dade County,

Of all the areas touched upon by the research project, this area--

pesticide effects upon wildlife--was probably the most difficult to assess









and the most difficult to speak about definitively. Some of the thoughts

presented here will be discussed further in the section entitled "Environ-

mental Constraints and Wildlife."

Ignorance in this area is twofold. First it is not understood how

sub-lethal exposure affects a given species; and second, if sub-lethal

exposure does affect some species, how this will affect other species

through the ecological system is unknown. Research on the former is now

moving along rapidly, but statistical evidence to date has been inconclu-

sive-and, in some cases, contradictory [32; 37; 39; 66; 70]. Research on

the latter is in its infancy, and results which would be useful for policy

3
formulation will probably not be available for several years.

A series of memos describing certain major species in the Everglades

National Park was obtained from the Park biologists, but these were writ-

ten in such general terms that it was impossible to develop population

estimates from them. Dr. Willaim B. Robertson,. research biologist, stated

that he had observed no distinct relation between pesticide usage and the

population of wildlife species in the Park.4

Two'hopefully unbiased conclusions about the position of biologists

were reached from discussions with them.

First, biologists are far more afraid of chlorinated hydrocarbons as

a group than the organic phosphates and would favor policies designed to

encourage the substitution or organic phosphates for chlorinated-hydro-

carbons. This stems from a feeling that long-term, sub-lethal exposure

3
These two areas of concern and their relationship to public policy
formulation within the framework of the model are discussed in the next
chapter.
From telephone conversation with W. F.Edwards.
From a telephone conversation with W. F. Edwards.










to the chlorinated hydrocarbons is detrimental, primarily to the repro-

ductive process. Since organic phosphates decompose quickly in the envi-

ronment, their effects tend to be acute and are not likely to have hered-

itary ramifications.5

Second, while there is not as yet conclusive proof of the long-range

detriment of low exposure levels, the circumstantial evidence is increasing

rapidly [33].

In summary, the opposing positions seem to reduce to:

Biologists: "Until the chlorinated hydrocarbons are proved harmless,

they should not be used."

Farmer: "Until the chlorinated hydrocarbons are proved harmful,

they may be used."

5.- Community Studies on Pesticides. Another source of information

on externalities in Dade County was the Community Studies on Pesticides,

a program of the U. S. Public Health Service and the Florida Department

of Public Health, under the direction of John E. Davies, M.D.

At the time of this study the Community Studies Program consisted

of a nationwide series of epidemiological and ecological studies on levels

of pesticides in the human population and environment of selected study

areas. The projects were contractual arrangements with state boards of

health and medical schools or universities whereby the Public Health

Service could arrange for and support investigations'of the effects of

5
This hypothesis is being questioned however. Some believe that
there may be long-term accumulative damage from the use of relatively
non-persistent pesticides [61, p. 347]. It has also been pointed out
that persistence of parathion is significantly affected by microbial
activity, the persistence being much less in biologically active envi-
ronments [52, p. 1].




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