Agriculture Tcson, University of College of Agricultu e

Agriculture Tcson, University of College of Agricultu e

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in Arizona lume XXI, Number 4

July-August, 1969



College of Agricultu e

University of



Arizona 85721

Agriculture's Future May Expand


In this issue of Progressive Agriculture in Arizona there are two articles to which I would like to call your attention.

The first is an article prepared by

Dr. Robert E. Dennis and John W.


Dr. Dennis is our agronomist with the Cooperative Extension

Service and Mr. Michel is Deputy

In this Issue

. .

Summer 4 -H Fun by George Alstad and Keith Jones

Director of Agro- Industrial Complex

Study at Oak Ridge National Laboratory.

In this article these two men present information to show how Arizona's unique desert conditions would, or could, be an ideal combination for the additional development of water, electrical resources which can then

Agriculture's Future May Expand by Harold E. Myers

Projections of Net Income and Water Use in Pinal County, Arizona by William E. Martin, Thomas G. Burdak and Robert A. Young

Agricultural Aspects of a Nuclear Powered Agro- Industrial Complex by Robert E. Dennis and John W. Michel

Consumer Attitudes Towards Milk Substitutes by Robert G. Angus and J. Warren Stull

One to Control: the Elm Leaf Beetle by George Wene

Precision Bedshaping and Planting for Cotton by M. D. Cannon and G. D. Christenbury

Arizona's Citrus Certification Program Celebrates Anniversary by Ross M. Allen and H. H. McDonald










Progressive Agriculture in Arizona

July -August, 1969, Volume XXI, Number 4

Published Bi- Monthly by the College of Agriculture, including Agricultural Experiment Station,

Cooperative Extension Service and Resident Instruction in the College of Agriculture and the School of Home Economics at the University of Arizona, Tucson, Arizona 85721.

Act of August 24, 1912.

Second Class postage paid at Tucson, Arizona.

Harold E. Myers, Dean.

Entered as second class matter March 1, 1949 at the Post Office at Tucson, Arizona, under the

Articles and illustrations in this publication are provided by the faculty and staff of the College of Agriculture.

Editorial use of information contained herein is encouraged.

Photos or other Illustrations will be furnished on request.

Editorial board members are: Drs. Mary Ann Kight, William R. Kneebone, Darrel S. Metcalfe

(ex officio), James J. Sheldon; and Messrs. Harvey Tate, and George Alstad, chairman and editor.

be applied to our irrigated -type agriculture as well as the extraction of minerals.

As the population of this globe continues to grow and double at shorter intervals it may well become highly necessary to put into full utility those lands not now in use for just survival, if for no other reason.

Thus, I urge you to read the article starting on page 4.

You may find it a highly interesting article, particularly if we think of it in terms of applying such technology to the lower

Colorado River under joint agreement between the two governments, the

U. S. and our neighbor to the South.

The next article of interest is that devoted to the consumer attitudes towards milk substitutes.

Another of promise is the article prepared about the new Precision Bedshaping equipment being tested at the Cotton C


ter by Dale Cannon.


Also, please notice the announcement of a control for the Elm Leaf

Beetle; as well as the first anniversary for the Citrus Certification program.

These articles represent only part of the recent accomplishments of our

College of Agriculture where men and women in research, in the classroom and in the Cooperative Extension

Service work hand -in -hand in search for answers to old as well as new questions.

They keep up this energetic pace in search for the new which may help you, the citizens of Arizona, conduct a sound and healthy business and family life.



Harold E. Myers, Dean

College of Agriculture, and

School of Home Econonit

Projections of Net Income

& Water

Use in Pinal County, Arizona

by William E. Martin, Thomas G. Burdak and Robert A. Young*


Problem Setting

Large -scale pumpage of underground water for crop irrigation in

Pinal County has been followed by a rapid decline in the underground water level. Public concern has been expressed as to the future of agriculture and other water -using industries in the face of this falling water table and the consequent rise in water costs.

In order to provide criteria for selecting between alternative private and public policies to combat this falling water table, it is necessary to pro -

^t the consequences of each such alalive. Previous empirical projections of either hydrologic or economic activity have taken the other activity as largely given. A complete analysis, however, requires that the interactions between the irrigated farming sector of the economy and the physical state

of the underlying aquifer be esti-


We had previously made economic projections of agricultural activity in

Pinal County over the next 40 years, using a technique involving linear programming on a digital computer.

About the same time, projections of groundwater table decline were being made by the U. S. Geological Sur-

* The authors are Professor, Research

Assistant, and Associate Professor, respectively, in the Department of Agricultural

Economics, The University of Arizona.

vey, using an electric- analog model of the aquifer developed by Thomas Anderson of their Phoenix office.

By combining the two analyses we were able to obtain projections that recognize the interrelated nature of agricultural activity and the state of the aquifer.

Interrelated System

The interrelated nature of the agricultural- aquifer system should be emphasized.

It is obvious that as irrigation water pumping costs increase, farmers will change both the way in which they grow crops and the num-

(Turn to Page 24)

Table 1.










Acreage of Field Crops, Net Revenue Over Variable Costs and Water Use, Pinal County,

1966- 2006.a

American -

Egyptian Upland







Wheat &




Acres water


Net Revenue


Variable Costs

1,000 acres (1,000 acre -feet)












Actual Reported

























Model Projections


























a The first three rows are reported acreage gramming - aquifer analog model.

in 1966, 1967 and 1968. Data in all other rows are projections of the integrated linear prob Barley, wheat and miscellaneous other tically identical at present.

field crops are treated as a single activity since net returns and resource requirements are prac-

Barley is the more significant; in

1968, barley acreage was 47,800; wheat, 12,400; and other crops,


4 urce: Arizona Crop and Livestock Reporting Service and Arizona Agriculture.



Energy is the most important commodity in the universe. While energy cannot be created or destroyed, it can be harnessed to do work for the benefit of man.

In recent years we have witnessed the development of massive energy source nuclear reactors.

Alvin M.

Weinberg, Director of the Oak Ridge National Laboratory of the Atomic Energy Commission, in a 1968 address to members of the American Society of Agronomy said,

"Today there are




100 nuclear power reactors operating, under construction, or on order. Their combined output will be


about 25% of the total electric power generated in the United States."

In 1968 nearly two -thirds of all new electric power plants in the United States used nuclear power as the source of energy. The fact that nuclear power can be profitably harnessed to produce low -cost electricity is no longer disputed.

The source of fuel for the nuclear reactor is not bulky and it is virtually unlimited, particularly with the advent of the breeder reactor. This type of reactor is capable of using "residual uranium and thorium as found in granites" and will produce more fuel than it consumes.

Agricultural Aspects



Nuclear Powered

Agro -Industrial Complex by Robert E. Dennis

John W. Michel*

Energy Requirements Increasing

Demographers predict that the population on earth will be about 7.2 billion by the year 2,000, more than double that of today. Each day there are about 190,000 more persons in the world than the day before. From a survival standpoint, to say nothing of social problems, population increase has profound implications concerning future food, fiber and energy requirements.

Irrigated Deserts Very Productive

Yields of agronomic crops are increasing in the United

States and throughout the world. These increases have been greatest in irrigated areas. In Arizona the average per acre yields for irrigated wheat, barley, sorghum, alfalfa, and cotton have doubled during the past 25 years and these yields are more than double of the non -irrigated areas of the United States. Other irrigated agronomic and horticultural crops are very productive. Today's higher yields with irrigation, double or triple those of the state, will probably become the average for the state during the next 10 to 20 years.

It was with this background that

R. P.

Hammond, of the Oak Ridge National Laboratory, in 1967, first suggested the possibility of using desalted water from a nuclear reactor for irrigation agriculture. In the summer of that year the Oak Ridge National Laboratory undertook a study of the feasibility of nuclear powered agro-industrial complexes to produce food and fiber for an je creasing world population. Desalted water from suclW complex would be used for irrigation while the electricity

Agronomist with the Cooperative Extension Service of University of Arizona and Deputy Director of Agro- Industrial Complex Study at Oak Ridge National Laboratory.

























-- 0.4

















E 0.4


1- 0.2













Figure 1.

Nuclear Powered

Agro- Industrial Complex.





Figure 2. Evapotranspiration of the Sinai -Negev

Locale and the Kutch Region of India.







MAY would power a nearby fertilizer, chemical and metal lurgical industry and be used to satisfy general urban and agricultural requirements, Figure 1.

Location of an Agro- Industrial Complex

About one -third of the soil of the earth is dry and unused, and one -half of the population of the world is now living on only one -tenth of the land area. It is estimated that there are 20,000 miles of desert sea coast in the world, having access to unlimited quantities of sea water.

Sites selected for the agro- industrial complex would need satisfactory soil easily accessible for irrigation, and favorable year -long growing climates. From an industrial standpoint the site should also have ready access to appropriate raw materials. Areas without energy sources

ç d fresh water but with mineral deposits would be most active.





Ten Agronomic and Horticultural Crops


Ten crops representative of different plant types were evaluated in the feasibility study

( wheat, sorghum, tomatoes, potatoes, safflower, soybeans, citrus, cotton, peanuts, and dry beans )


The choice of crops for stances.

a particular locale would depend upon local conditions and circum-

Estimation of Water Use by Crops

Consumptive use estimates were made for all crops for a representative Mediterranean site in Israel and another in India, using a semi -empirical energy balance equation. Computations were by M. E. Jensen, Research

Agricultural Engineer, Snake River Conservation

Research Center, U. S. Department of Agriculture,

Colorado ( Figure 2).


(Turn to Next Page)


Wheat as a Crop in the


In 1967 and again in 1968, several newly developed wheats produced more than 6,000 pounds per acre in a

University of Arizona Agricultural Extension Service to + on the Floyd Spar farm, Yuma County, Arizona ( Fig



Economic analyses indicated that wheat, with a yie tiÌ of 5,200 pounds per acre, would be feasible in developing countries ( Figure 4 )


In the analysis it was assumed that day length insensitive spring wheats developed by Borlaug and associates of the Rockefeller Foundation, in cooperation with the Mexican government, would be used.

Many of these varieties have a yield potential that is more than double the assumed 5,200 pounds.

One of the new spring wheats is Sonora 64. Laboratory tests have shown that it is a good milling wheat, higher in protein than many other spring wheats. Data concerning yields of the newer wheats are cited to show the relatively conservative nature of the yield estimates used in the Oak Ridge studies. Time does not permit discussion of all of the crops but each received exhaustive study.


Figure 3. Floyd Spar, left, Director and Past President of the Arizona Crop Improvement Association, and

Don Howell, Yuma County Agricultural Agent, observe Sonora 64 wheat on the Spar farm near

Wellton -Mohawk area. This wheat yielded more than three tons per acre.

Climate and crop stage of growth information were used in the equation.

A. D. Halderman, University of Arizona Extension

Agricultural Engineer, and others are conducting investigations in which the Jensen equation is used to program irrigations. Preliminary results of their work indicate that the Jensen equation is a practical and effective device for estimating consumptive use.

Water delivery requirement estimates assumed the use of sprinkler type irrigation and an 80% water use efficiency. No consideration was given to precipitation, a factor that could be expected to reduce the water delivery requirement at most locations.

The Farm Layout

The layout plan for the Agro- industrial complex would be determined by the geomorphology of the area selected. In considering the layout for the farm, the study group assumed production of one billion gallons of water each day with a lift of 200 feet to the central canal that would extend through the center of the irrigated area.

Because of lower consumptive use rates during the winter, a larger area for winter than for summer irrigation would be required. Depending upon the crops grown,

18 to 26% of the total water produced would be stored in underground aquifers.

This water would be pump and used as needed ( ten per cent water loss was assum for water stored in this manner)


The irrigated area for the Agro- industrial complex would range from 280,000 to 320,000 acres, depending on the cropping system used ( Figure 5 on page

). Investment expense for land and its improvement, the irrigation system, farm machinery, storage and other costs

46 50


COST OF WATER (i /acre -ft)





Economic Comparison of Crops

Costs of seed, labor, machines, fertilizer and other chemicals, water, storage and marketing, electrical power and other expenses were estimated for each of the 10 selected crops.

These costs ranged from $150 for dry beans to $817 per acre for citrus with water at $0.20 per

1,000 gallons. An additional $75 per acre was charged for fixed charges. An interest rate of 10% was assumed for capital required.

Safflower, soybeans, sorghum, and peanuts failed, at world market prices, to produce sufficient income to pay direct production costs. Balance of payments and other factors must be considered in an evaluation of the agroindustrial complex. At a price level of world market plus

30 1/4 which corresponded on the average to the internal crop prices of many developing countries, most crops produced economic returns.



3 2.4


-Nu) o


4 .6






40 45

COST OF WATER (ç/ 1000 gal )

Figure 4.

Cost of Growing Wheat



The dairy industry is confronted with the encroachment of substitute milks into the fluid market.

These products are new in terms of market availability even though the technical development took place in the fifties.

Marketing substitute milks introduces the butter -margarine controversy in a new form.

Substitute milks have been sold at lower prices than regular milk because butterfat has been replaced by relatively low -cost vegetable oils.

The product is available in approximately 20 states and sales are expanding. The rapid growth in

the relative market share of filled

milk in Arizona to ten percent of the

Class I producer milk since its introduction in October 1966 has drawn

the attention of those people par-

ticularly concerned with evaluating the competitive potential of fluid milk substitutes.

The purpose of this paper is to present the results of a study of factors that may explain the acceptance of filled milk in terms of consumer attitudes and alternatively in terms of the different characteristics of consumers and nonconsumers of filled milk. The results of our study are compared with a study made by the Milk Industry

Foundation' in Arizona.

These two studies were completely independent; the investigators had no knowledge of the other until the field work was finished.

Information was obtained on consumption, price, and place of purchase for 56 food products. Respondent households were selected at random from the Phoenix area during



Attitudes toward milk products were investigated by using

30 polar statements with a seven unit intensity scale.

To facilitate discussion these results have been divided into use; three categories : (1)


( 2) Consumer Characteristics; and ( 3 ) Nutritive characteristics.

Product Use

Respondents were less familiar with imitation milk than whole milk.

Of those questioned nearly half had never heard of imitation milk.

Six times as many families used milk frequently as those who use imitation milk often. A ratio of 3:1 was found between those who never used imitation milk and families that never used regular milk.

Families that purchased substitutes the previous week consumed an average of 10.9 quarts of milk -type beverage per week; 4.9 quarts of regular






by Robert C. Angus and J. Warren Stull*

milk and 6.0 quarts of substitutes.

Those families that did not purchase substitutes last week consumed a total of 10.1 quarts of milk per week.

The MIF study reported weekly household consumption of whole milk, other milk and substitutes as 9.62

quarts. This figure includes .75 quarts of substitutes.

Nonusers of substitutes consumed 8.96 quarts per week while substitute users had a milk type beverage consumption of 13.98 quarts, composed of 4.5 quarts of whole milk,

1.83 quarts of other milk and 7.65

quarts of substitutes.

Milk consumption figures from the two studies are in close agreement.

The proportion of total milk beverage consumption accounted for by substitutes for regular users was 54.7 percent in the MIF study versus 55.1 percent in the Arizona work. Less regular milk is consumed by families purchasing substitutes.

The difference was statistically significant.

A key toward evaluating potential market acceptance of substitute produces may be found in the volume sold in Arizona. At present, about 10 percent of the Class I producer milk is filled milk products.

This proportion has been stable since July 1968.

Price comparisons for the Phoenix area found imitation milk selling for

39 to 43 cents per half gallon during

June 1968. Regular milk was priced from 53 to 56 cents.

The MIF study reports a seven to nine cent spread between these prices for July 1968.

Consumer Characteristics

Chi -square tests for independe of samples were used to examine t polar statements related to consumer characteristics.

The attitude proposition, "Not liked by children


Liked by children," resulted in a 7:1 ratio between imitation milk and regular milk on the "not liked" side. The ratio was 4:1 in favor of whole milk on the "liked" side.

Frequencies for the

"Liked by adults





Not liked by adults" question pointed to a preference for regular whole milk.

Imitation milk was liked by the entire family for only 14 percent of those interviewed.

Two questions dealt with sex differences via the "Women's drink

Men's drink," "Boy's drink



Girl's drink" scales. Imitation milk is considered by many to be more of a woman's beverage.

However, the

"boy- girl" scale did not reveal significantly different frequencies.

One explanation is that respondents thought imitation milk had less calories, was watery and was for weight watchers.

Robert C. Angus is Professor of Agricultural Economics and J. Warren Stull is Pro-

sity of Arizona.°`

Thus, the imitation beverage may have more appeal for women than for girls who would have less serious lorie control problems.

OThe responses on "For company .. .

Not for company" indicated regular milk was the drink to be served guests.

One explanation is that imitation milk may be thought of as an inferior product.

Regular milk was preferred for personal use.

The next step in the analysis consisted of an examination of the difference between families which purchased imitation milk last week and those who did not. This comparison includes the following factors : (1) education of homemaker; ( 2) disposable family income;

( 3 ) family expenditure for food eaten away from home; (5) size of household; ( 6) age of homemaker.

The average homemaker in families which purchased imitation milk had significantly more education than her counterpart. The difference was very small, imitation milk users completed one trimester while nonusers had four years of high school and no college.

The disposable family income for users and nonusers was not significantly different. The nonuser group averaged $7892 opposed to $7929 for u sers.

Comparison of these income ures with those in the recent Milk dustry Foundation study is difficult because of the refusals and wide income classifications in the MIF report.

The MIF report concludes that, "It is clear that substitutes are not being purchased primarily by the lower income groups." This conclusion is supported by the Arizona results.

No significant differences were found between users and nonusers for family expenditures, for food eaten at home or for expenditures for food eaten away from home.

The average size of household for purchasers of imitation milk was 4.6

persons versus 3.9 in the other group.

This difference was not significant.

The MIF study reported a higher proportion of larger families were regular users of milk substitutes than smaller families.

The Arizona results agree but again the difference was not significant at the five percent level.

No significant difference was found between the groups with respect to the age of the homemaker. Perhaps number of children under 16 years would have been a better variable.

Nutritive Characteristics

OThe ingredient characteristics of substitute milk beverages vary widely because standards of identity have not been adopted by most judicational areas.

The fat used in many pro-


is based on hydrogenated

vegetable oils.

In some filled milks, isolated proteins are used in addition to unspecified amounts of nonfat milk.

Likewise, there is variation in fortifying these beverages with minerals and vitamins.2

Questions dealing with vitamins, calories, general nutritive value, protein, and calcium were included so that consumer knowledge could be compared to product characteristics.

Responses relating to caloric content were particularly interesting.

Seven times as many indicated imitation was low in calories as compared to regular milk. This opinion is not supported in fact. Filled milk has approximately the same fat and nonfat content. This result is supported by the MIF study where 63.9 percent of occasional users of milk substitutes thought it had fewer calories than regular milk. Regular milk was considered to be less watery or richer and more stylish.

Families frequently pointed out a greater uniformity in the quality of regular milk.

The response to For weight watchers


For thin people" showed that the imitation product was thought of as a weight watchers beverage.

Consumers identify the sub-

stitute with diet type or low fat


The protein question resulted in high ratings for regular fluid milk.

Consumers are generally aware of the relatively high calcium content of whole milk.

In reality filled milks have the same protein and calcium content as whole milk provided the nonfat solids proportion is equivalent.

The preceding analysis was based on the entire sample of users and nonusers of imitation milk. The breakdown of contingency tables has been extended to compare attitudes toward imitation milk by those who purchased the product last week and those who did not. There were no significant differences between purchasers and nonpurchasers of imitation milk in their attitudes toward product content of vitamins, calories, protein, calcium, and general nutritional value.

In contrast, there were no significant differences between imitation milk purchasers and nonpurchasers in their attitudes toward regular milk with respect to content of vitamins, calories, and protein.

In summary, both groups were equally well informed and equally confused about regular and imitation products.


Attempts to explain why consumers ranked imitation milk and whole milk

as they did verge on speculation.

However, one must note the attitudes

which do not conform to


There were several of these. The major one was the low evaluation for caloric content of imitation milk. This led to ranking it as a diet product.

This fact was also reported in the

MIF paper. A second factor prevails over the responses.

Regular whole milk has a

"good," "wholesome" image.

This image may have led

families to answer favorably for regular milk even though they had little or no concrete knowledge on a specific question.

The University of Arizona research and MIF work agree closely. The real question deals with directions for additional investigation. Is our information base good enough to form market policy?

A naive multiple regression model was constructed with milk consumption as a dependent variable and a set of quantifiable demographic variables as independent variables. The coefficient of multiple determination

(R2) was .397. The significant variables were as follows : education of homemaker, a negative relationship; expenditures for food eaten at home and away from home, a positive relation; and the number of persons in the household, a positive relation.

Disposable family income and the age of the homemaker were not significant. Additional independent variables can be added from the data.

One example would be the number of family members under 16 years of age.

Intercorrelations among independent variables are a serious problem in this type of analysis.

The point in discussing this regression analysis is that it highlights the problem for researchers.

The real question for researchers is identifying the relevant variables which are related to milk and substitute milk consumption.


I Call, D. L., and L. J. Wilkerson. Consumer Acceptance of Fluid Milk Substitutes in

Three U. S. Markets. A Research Study

Published by the Milk Industry Foundation,


2 National Dairy Council. 1968 Relative Nutritional Value of

Filled and Imitation

Milks. Dairy Council Digest, 39 (2).



Summer 4 -H Fun

by George Alstad & Keith Jones*

4 -H boys and girls bounce into the program with enthusiasm when Pinal County holds its summer 4 -H camp near Williams in northern Arizona.

And, as each jam -packed day comes to an end there barely is enough time to rest up for the next full day of activities.

For two years, now, the Pinal 4 -H Camp has been in operation.

The camp is situated on seven acres of a combination of forest and mountain meadow .



an ideal location.

As reported in an earlier issue of Prgik gressive Agriculture the Combs' of Queen Creek - MT'

Lyla Combs and Mr. and Mrs. Willis

( Bill) Combs donated the land.

Buildings, furnishings and all of the other equipment needed for a camp were donated by 4 -H supporters in Pinal County.

Photos on these pages show some of the boys and girls as they enjoy this year's camping.

Moving counterclockwise starting above this page are:

Mrs. Tracy Hutchins preparing sloppy joes for lunch; Pat

Renfro dishing up salads for the hungry ones at her table; and

Mark Taylor who scored high in archery.

Dropping down the page is a long view of the open meadow used for dining, softball, archery.

Meals are prepared on open barbecue grills.

In the background the forest area contains cabins in which all 4 -H'ers are housed.

Next are Anna Maria Guzman, left, of Kearney and Tammy

Combs of Queen Creek.

Seated around the table in the lower left photo starting with the boy with cup in hand and moving clockwise are : Paul

Cooper of Kearney, Anna Jackson of Sacaton, Gretchen Winkle of Kearney, Carlton Hoover of Casa Blanca, Craig English of

Casa Grande, Karen Matheny of Kearney, Debra Pratt of Mari copa, (standing is John Fearn, Jr., of Casa Grande) ,


Reed of Florence, Susan Goff from near Owl Head who is looking this way, and with back to camera is Deana Lefler of Kearney.

The rifle range is far removed from the rest of the campers and it is here that they are taught safety and proper handling of arms.

Kneeling nearest to camera is Lester Dawson, Agricultural Agent at Sacaton.

He is a member of the University of

Arizona Cooperative Extension service.

In the golf cap towards the rear is Art Lefler of Kearney. He is one of the many 4 -H supporters in Pinal County giving their time that the 4 -H boys and girls may experience camping.

Archers take their training and practice at the archery range also situated to prevent accidents.

Moving clockwise on page hikers ascending Beacon



, Keith Jones heads the line

In downhill order from Jones

Cathy Wilkins of Queen Creek, Jerri Lemon of Kearney,

_ ances Hildebrandt of Queen Creek, Betty Hunsaker of Kearney,

Brent Murphree of Maricopa, Kari Hutchins of Stanfield and

John Matheny of Kearney.

In upper right corner completely enjoying each other's company are Ruth Luna, left, of Casa Blanca and Gretchen Winkle of Kearney.

In next photo right Roy Swisher, a Coolidge accountant from left, is flipping French toast, apparently not fast enough for Mark Taylor of Stanfield, Paul Smith of Maricopa, Carlton

Hoover and Darwin Thompson of Casa Blanca. Helping Roy is

Ellen Hosking, Home Economist in Pinal County Extension


Lower right picture shows the flag being lowered while the setting sun is peeking through the trees on Beacon Hill.

In next picture Mary Ann Pratt of Maricopa is preparing carrots for salad while Carlton Hoover and Darwin Thompson (left to right) of Casa Blanca continue braiding a colorful whistle cord.




Larva and


One to


by George Wene*

the underside of terminal leaves of the branches. These hatch in about

7 days. Newly hatched larvae are black in color but change to a bright yellow within three days.

These larvae or worms feed and grow for

20 days and then migrate to a pupation site where they remain in a resting stage for 4 days, after which they change to pupae.

Eight days later the adults emerge. Adults will feed for 14 days before laying eggs. In the laboratory each female laid an average of 15 eggs. Adults have lived as long as 50 days, laying eggs anytime during that period. The average life from egg to adult is 29 days.

Ther fore, in southern Arizona it is possibir, to have 5 or more generations during a season.

Young larva


The elm leaf beetle is the most destructive pest of Chinese elms in Arizona. This insect is very ravenous and can destroy all the foliage of an elm tree by the first of June.

Such destructive feeding weakens the tree and can kill it in a few years.

Fully mature larvae become a nuisance in their search for a pupation site. Pupating larvae at the base of the tree are repulsive. Most people cannot tolerate larvae migrating over patios, or porches, in houses and even between the sheets on beds located on porches.


Life History

The elm leaf beetle adults are one fourth of an inch in length, buff colored with an olive green stripe along the outer edge of each wing cover.

During the winter the adults hibernate inside of buildings, under trash, or any protected place which is not too damp. In the spring they emerge from hiberation at the time the elm tree starts to leaf which is around the first of March in both Maricopa and

Pima counties. These adults eat circular holes in the leaves.


April 1 bright yellow eggs are laid on

Feeding Habits

The adults will feed only on the tender terminal growth of terminal leaves.

If no succulent leaves are available the adults will then fly to more desirable trees for feeding and egg laying.

Eggs are laid on the tender leaves of terminal branches of the lower limbs. As the lower tender leaves are destroyed the egg laying takes place on the higher branches.

After feeding for eight days or more on the tender leaves the larvae will move to the tougher leaves and destroy them.

During August many trees go into a semi -dormant stage of growth, usually due to a lack of sufficient water.

The leaves become tough. Adults cannot live long on these leaves and move away. Because these leaves are tough, the females will not lay eggs. One of the ways of controlling a mid -season

*Associate Entomologist, Department of Entomology.


the elm Leaf


infestation is to withhold the irrigation water, which isn't very good for a rapid growing tree.




( Sevin )

at 2

pounds per 100 gallons of water will give effective control. Malathion and diazinon at 1 -pound per 100 gallons of water is also effective. In order to prevent leaf damage sprays must be

applied at 10 to

14 day intervals while trees are growing vigorously and producing new leaves. As many as eight spray applications may be needed during a season.


Soil drenches of oxydemetonmethyl ( Meta

- Systox -R

) or dimethoate ( Cygon ) will give control

0f r a six week period on elm trees with nks varying from one to 14 inches n diameter. For each inch of trunk diameter add 25 ml. of emulsifiable concentrate of pounds per gallon ) dimethoate

( two to 2.5 gallons of water and pour into basin around the tree.

For a one -inch diameter tree trunk the radius of the basin should be one foot, whereas that of a 14inch tree should be at least five feet.

Wetting the ground of the basin before adding the drenches will aid the effectiveness of the drench.

CAUTION: Rubber gloves should always be used when working with either oxydemetonmethyl or dimethoate because both of these insecticides are poisonous.

Trunk Injections

On trees with a trunk diameter of six inches or more dosages of

Bidrin or oxydemetonmethyl implanted into the tree trunk at six -inch intervals around the circumference of the tree give effective control. The Bidrin treatment will last from six to 12 weeks. Tests show that oxydemetonmethyl will only give control for a period of four to six weeks.

Because of the toxicity of these materials only approved pest control operrs can apply these treatments.


Dr. George Wene is driving the tube into the sap stream (cambium layer) of the tree trunk in preparation for introduction of either Bidrin, or oxydemetonmethyl insecticides.

Here he is placing the pressurized insecticide capsule on the same tube which was driven into the trunk in top photo. This means of insect control is rapid.

It takes less than one hour for insects to fall away from the tree - dead!

the inexperienced.

It is not a method for

It must be done by the professional who can take adequate cautions against the highly toxic materials.



Precision Bedshaping and P1antin for Cotton

by M. D. Cannon and G. D. Christenbury'

The practice of precisely shaping beds for planting is not new; vegetable growers have been doing so for years.

As a matter of fact, it was from seeing the vegetable fields that the idea was developed to use a similar system for cotton, although it did not come in a sudden, blinding flash. Actually, it "just sort of grew like Topsy."

The seed of the idea probably germinated during the earlier days of using plastic and asphalt mulches, for these materials require a relatively smooth, shaped surface.

But the real need for bedshaping arose because of herbicides.

Some of the more effective herbicides are phytotoxic to cotton, and one of the early problems was how to maintain physical separation between the germinating cotton and these herbicides.

The reasoning was logical.

If we could apply the herbicide in the top 3/4 to 1 inch of soil in a precise layer, then plant the cotton seed underneath so the roots would not take up the chemical, we were reasonably certain that weeds could be controlled without damage to the cotton plants. The next step in our thinking was that we


the trapezoidal bed, depending on the crop.

A number of listed beds were measured to determine the volume of soil in the cross section.

An experimental shaper was then built using a top that tapered from 8" at the front to 6" at the rear.

Hinged side plates were then used, for we did not know exactly what angle would






Figure 2.

Cross section of bed.

serve for the side slope. We tried this machine in t field and chose a side slope of 1:1, so the final shape of the trapezoidal bed had a 6" flat top and a nominal

height of 10" from top to furrow bottom.

For 40" spacing this left a furrow bottom width of 14 ", sufficient for most of our tractor tires to run in without breaking down the side slopes.





Herbicide placement with the Pre-Shaper in the schematic above; and with the Shaper -Planter -Incorporater below.

needed a "datum plane" from which to work in order to incorporate the chemicals to a precise depth. Thus was born the idea to steal a march from the vegetable growers.

We reasoned that cotton would require a different type or shape bed than vegetables, since the cotton producer plants only one row every forty inches, whereas the vegetable grower may plant from two to six rows on top of









Figure 3.

Profile along the row.

Once we had decided on the bed shape it then remained to see what would happen if we applied the phytotoxic herbicides, incorporated them and planted through them.

The incorporator was constructed and powered by a hydraulic motor.

It was mounted on the front of the shaper.

Just behind the incorporator we cut a slot in the top of the shaper and mounted a hill drop planter with a modified opener.

The bottom of the opener was set one inch deep, and the incorporator was set to stir the soil to a depth of 3/4 -inch.

First tests were encouraging.

The herbicide controlled the weeds in the 6" band, and the cotton was unharmed, but the herbicide for controlling weeds on the slopes and in the furrow had to be applied separately.

Necessity being the mother of invention, we came up

Associate Professor and formerly Assistant Agricultural Engine respectively, both of the Agricultural Engineering Department.


Figure 4.

The preshaper forms the bed while the spray nozzles apply herbicides to the sloping sides and bottom of furrow.

Figure 5.


This is head -on view of final shaper with incorporater

The top of the shaper is eight inches wide at the front and tapering to six inches wide at the rear.

This theoretically has a firming action on the beds.

It has been found that the beds do not slough off after irrigation, perhaps due to this firming or "squeezing" action.

Figure 6.

This is a closeup of the incorporater. The effects of

'king rocks can be readily seen on the teeth.

Figure 7.

This is a rear view of the machine showing the planters and rolling cultivator sections for incorporating herbicides into the furrow bottoms. The applicator for dry systemics, not seen in the picture, is mounted just above and in front of the planter hoppers.

with the idea of spraying the sides of the beds and the furrows ahead of the shaper, but with all the stirring and mixing done by the shaper, we were not sure where the herbicide would end up.

Then we considered using a preshaper mounted on a cultivator gang in front of the drive wheels on the tractor. This would give us a smooth surface approximately the same shape as the finished bed, and the second shaper might give us enough incorporation along the slopes to make the chemical work.

This left only the furrows, so rolling cultivator sections were mounted behind the final shaper to mix the herbicide into the soil in the furrow.

Earlier, in tests with the hill drop planter, the idea was conceived of dropping systemic insecticides in the hills in order to cut the amount, and thus the cost, of application.

This idea was tested, and we found that the rate of application could be cut to 1/4-normal if the systemic was fed into the hill drop mechanism and deposited around the seed, leaving the space in between untreated.

This idea was integrated into the system, so the machine is now capable of shaping, incorporating, planting and applying systemics, all in a once -over operation.

The machine in its entirety was first tested in 1966,

(Turn to Next Page)



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Figure 8.

This picture shows the row profile after irrigation.

Vertical marks are two inches apart while horizontal lines are one inch apart.

the field.

The photo was taken near the lower end of

Note that the furrow which was nearly ten inches deep when formed is now only seven inches deep. This is partly due to the settling of the entire bed as well as to silt deposition.

and the tests were repeated in 1967.

Results are shown in Tables I and II.

Have we solved all the problems? Not quite.

There are three basic problems with the system.

First, the field must be nearly dead level, at least level enough for subbing up without flooding the tops of the beds.

Flooding causes an impenetrable crust.

Second, the incorporator

Table 1.

Treatments and Yields for 1966 Crop

Year. Pounds of Seed Cotton per Acre




(Treflan) lb/A

Bensulide (Prefar)

2 lb/A

Planavin 3/ lb/A

DCPA (Dacthal)

9 lb/A

Diuron (Karmex)

1 lb/A

Prometryne (Caparol)

2 lb/A

Diuron 1 lb/A ± Trifluralin

.% lb/A

Diuron 1 lb/A ± Bensulide 2 lb/A

Average Yield










Table II.

Treatments and Yields for 1967 Crop

Year. Pounds of Seed Cotton

per Acre



Trifluralin (Treflan) % lb/A -!-

Diuron (Karmex) 1 lb/A

DCPA (Dacthal) 9 lb/A -±

Diuron 1 lb/A

Bensulide (Prefar) 2 lb/A ±

Diuron 1 lb/A

Planavin 3/4 lb/A ±

Diuron 1 lb/A

Trifluralin % lb/A ±

Prometryne (Caparol) 2 lb/A

Bensulide 2 lb/A -

Prometryne 2 lb/A

Average Yield







3,389 cracks.

Hopefully, this problem can be solved.

Interested producers often ask if this machine is available on the market.


The answer would have to be

While the exact machine is not available, at least one farm machinery manufacturer is now making a bedshaper with P.T.O.- driven incorporator. With a little imagination and some welding equipment this machine could be made to do everything ours does and probably better.



Ala ois not compatible with stony ground.

Third, weed control on the sloping sides of the beds is not hoped.

as good as we hil

After the soil drys, cracks appear along t slopes, and weeds, particularly ground cherries, will germinate below the treated layer and emerge through the

Figure 1.

Solid plantings of certified Kin now mandarin trees for which orchard certificates are being awarded by the Arizona Crop Improvement Association.



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Different calendar dates are important to all of us for a wide variety of reasons including birthdays, anniversaries, or other milestones related to passage of time. For Arizona's Cooperative Citrus Registration- Certification Program an important date was

July 28, 1969 on which the Program completed its fifth full year of operation since its approval in 1964.

In this time several important objectives have been attained and substantial progress towards other objectives is reported here.

The citrus certification program, which is completely voluntary regarding grower participation, serves these rowers through the close cooperation four agencies.

Certification and ministrative operations are per-

formed by the Arizona Crop Im-

provement Association.

All regulatory functions are conducted by the

Arizona Commission of Agriculture and Horticulture, whose district inspectors supervised planting, budding, growing, and tagging of certified trees for no less than 1,423 man -hours during the fiscal year 1967 -68.

Industry members direct

the program and

establish operating policy through the

Arizona Citrus Advisory


Technical guidance is provided by various members of the University of

Arizona Agricultural Experiment Station.

The principle objective for which the program was initiated remains unchanged to assist nurserymen and citrus growers to obtain budwood and grow citrus nursery trees from sources that have been tested and found apparently free from known virus diseases and other bud- transmissible disorders. While the primary plant enemies being attacked are the virus -caused diseases, the restrictions under which program trees are grown sufficiently strict as to practically guarantee freedom from diseases caused by bacteria, fungi, and nematodes as well.

Satisfactory progress toward attainment of this objective may be attested by the fact that practically all of the citrus nursery stock grown in Arizona during 1968 was under program supervision.

During the four and a half years ( July, 1964 through December, 1968 ) for which records are complete, more than one million certified citrus buds have been propagated.

In order to accomplish this, the University Citrus Farm at

Yuma has provided more than a quarter million buds from 256 registered foundation trees representing 63 citrus varieties.

Citrus nurserymen are preparing for the future by selecting and having tested outstanding grove trees which are called "parent" trees. These trees are the equivalent of foundation trees but are located in commercial orchards and are the property of the participating growers.

In addition,

498 young trees from registered sources have been planted in grower owned mother blocks.

Table 1 sammarizes the program's progressive growth from 1964 through 1968.

Any businessman would research the financial status of an organization or program in attempting to evaluate its past performance and its potential for future development.

It seems appropriate, therefore, to report the realization of a second program objective, that of becoming entirely self supporting regarding financial matters.

Initially, the citrus certification program was financed jointly by the

University of Arizona Agricultural Experiment Station and by voluntary contributions from growers and nurserymen.

Since July 1968, only four years since inception, the program has been entirely self supporting from income derived from inspection fees and

Arizona's Citrus Certification

. .


Celebrates Anniversary

by Ross M. Allen dr H. H. McDonald* sales of registered buds and tree certification tags. The magnitude of this accomplishment b e c o m e s apparent with the knowledge that the program supports a staff composed of a technician and the equivalent of two full time field and greenhouse assistants.

Capital acquisitions include office and soil sterilization equipment, a greenhouse providing 1680 square feet of space for growing and testing citrus plants, and an 800 square foot steel building which serves as a supply room and potting shed.

All operational expenses including supplies, labor, and travel, formerly provided by other sources, are now paid directly from program revenue.

The same businessman who investigates financial conditions of a concern would also inform himself about the management of the organization.

In the case of the Arizona Cooperative

Citrus Registration -Certification Program, a program developed for the citrus growers by the University of

Arizona with the growers' assistance, the program management and direction rests squarely on the shoulders of the growers themselves.

All operational and policy decisions are made by elected industry members with equal representation from the two principle citrus regions of the State.

(Turn to Next Page)

* Professor and Assistant in Research, respectively, Department of Plant Pathology.


Table 1.

Five -year summary of activities in the tion Program.





Foundation varieties registered


Foundation trees registered


Foundation buds issued Yuma

Registered buds from California program

Registered and certified buds propagated

Certified tree tags sold

Citrus nurseries in program

Registered parent trees released

(grower- owned)

Mother block trees in program

(grower -owned)

Nucellar seedling varieties planted

(Yuma) for eventual registration



















This group of men, known as the

Arizona Citrus Advisory

Council, serves also as the Citrus Commodity

Committee of the Arizona Crop Improvement Association, the program's administrative unit. Through this organizational scheme a third program objective has been realized that of full industry control and self -government.

It is truly an organization of the growers, operated for the growers, and controlled by the growers.

A business also is judged by its adaptability in changing situations and for up- dating adjustments to improve its product or service.

The rules and regulations governing the

Arizona program, originally approved in July, 1964, were completely revised in January, 1968. The most important revisions were for the following purposes: a. Expand the definition of a citrus nursery to include nursery stock g r o w n in individual containers

and to prescribe methods for

growing such stock under program supervision.

b. Enlarge the program's registration classes to provide for certification for stubborn disease, adopt a new class for budlines known to carry exocortis virus,

and prescribe identification

methods for nursery increase buds within each registration class.

c. Increase the time limit from 18 to 24 months that nursery increase block trees may serve as supplementary sources of scions for production of certified nursery stock.

d. Provide for a charge of eight (8 ) cents per bud for each bud in excess of 25 buds of each bud line issued from the program's foundation trees and to authorize

Arizona Cooperative Citrus Registration -Certifica-












Figure 2.

This husky certified frost Lisbon lemon tree bears its certification tag as proof that it has a good start towards a long and productive life.

























2 ?








124 a ten dollar ( $10) fee for initial inspection of nursery and seedbed sites.

e. Provide for issuance of certified orchard certificates for solid plantings of trees inspected and certified under the Arizona program.

Most of the rule changes described above are self- explanatory.

Item e, however, deserves special mention since it provides for records lasting the entire life of newly planted groves.

The owner of any solid block planting of properly tagged and certified citrus trees may request within a period of

one (1) year from date of plantiii

that the Arizona Crop Improveme

Association issue an orchard certificate for that planting.

The certificate shall indicate the owner of and legal description of the property, variety, rootstock, registration number and class of tree planted, the planting plan, and actual count of certified trees as existing at the time of certificate issuance.

It is thought that orchard certificates may be of considerable value as attachments to deeds or other legal forms during trade, sale, or other activities involving the property.

Voluntary requests for certificates for 425 acres of certified trees were received in 1968. More acreage is qualified for certificates and it is expected that more growers will apply for them, at no additional cost, as they become aware of the potential value of the certificates.

And finally our businessman appraises the product or service itself.

Is it worth the cost?

Will it have lasting value? Can a return be realized by investing? Exactly how much, in dollars and cents, will be the returns on the investment?

Such questions are easily answered for the








This is to certify that


of citrus block consisting of



Range plant on this property,


Trustees legal owner and /or operator acres described as the and of Section in the records of the State of Arizona, did, on or about certified citrus trees consisting of bearing registration number (s) and class (es) as assigned by the Arizona Cooperative Citrus Registration- Certification Program. Issuance of this certificate by the Arizona Crop Improvement Association is based upon an inspection of the planting as of


19 and any alterations in the planting after this date are the sole responsibility of the owner /operator.

Executive Secretary, ACIA

*In cooperation with the Arizona Commission of Agriculture and Horticulture and the Arizona Agricultural Experiment Station.

zona citrus certification program when one considers that average losses in

Arizona citrus production caused by virus diseases in old -line, untested groves have been estimated very conservatively to be $69.25 per acre per year.

Today, Arizona has approximately 32,000 acres of bearing citrus with a crop potential gross income that exceeds $23,000,000.

Probable realized income would be approximately $13,413,036 ( for a loss $9,297,-

282) if it were not for the fact that approximately 4,450 acres now bearing are of improved and virus -tested budlines.

There should be a saving of $308,162, at $69.25 per acre, for these 4,450 acres this year. This saving is an amount more than ten times the entire annual operating budget for the certification program.

And consider further, that during an estimated

40 year productive life of these trees that there will be $12,236,500 inased income not available prior to the production of these virus -tested trees.

Eventual benefits to the Arizona agricultural community will be greater in years to come.

Recent figures indicate there were 43,335 acres of citrus in Arizona in 1968, an increase of 14,257 acres since 1960.

It is estimated that 80 percent ( 11,405 A. ) of these new plantings is comprised of virus -free budlines.

Savings to industry on this acreage alone should be approximately $789,796 per year or $31,591,840 during the productive life of the trees. These savings might be considered in another way.

A grower has 5 acres of virus -free citrus trees producing $69.25 more in fruit than a comparable 5 acres of virus

infected trees.

The returns from the virus -free trees equal the returns of

6 acres of infected trees.

Thus, the increased returns amount to nearly 17 percent which makes the investment in virus -free trees a reasonably good business venture.

The Arizona



Registration- Certification Pr o g r am therefore proudly celebrates its 5th anniversary with realization of attainment of several prime objectives and with substantial progress having been made towards satisfaction of other goals.

In its short life the program not only has made a substantial contribution and economic impact upon Arizona agriculture but it stands as a prime example of a program, requested by growers, which was organized and developed by the

Arizona Agricultural Experiment Station, and has now been released to industry control as a completely functional and self- supporting unit.

( For anyone interested, complete copies of the program rules and regulations

( revised January, 1968 ) are available through the Secretary,

Arizona Crop Improvement Association,

University of Arizona, Tucson 85721.)


Pinal County

(From Page 3)

ber of acres of each crop grown.

Acreage of low- valued crops such as barley and alfalfa will be greatly influenced by rising water costs, while high- valued crops such as cotton and vegetables will be affected hardly at all.

When crop acreage is changed, the quantity of water pumped changes.

When the quantity pumped changes the rate of decline in the water table changes. A different rate of decline implies a different rate of adjustment by farmers to changing water cost.

Our analysis begins with estimates of the number of acres of each crop grown, and the water use of each.

We can then estimate the quantity of water pumped in each subarea of the county for a given time period. These estimates are developed using linear programming analysis a mathematical procedure solved on the digital computer. The quantities of water pumped during the time period are the inputs into the electric- analog model.

Anderson describes this model as follows:

An electric -analog model is an electric system that is analogous to the groundwater system. Resistors simulate the ability of the sediments to transmit water, and capacitors simulate the storage of water within the soil pores.

The response of the model to the

simulated pumping stress

is shown on an oscilloscope in the form of a hydrograph. By measuring with the oscilloscope at different points, it is possible to prepare a contour map of water level changes caused by a specific stress applied for any specific length of time.

These estimates of changes in depth to water allow new water cost esti-

mates to be entered into the new

linear programming model of the next time period.

This cyclical procedure is continued until the end of the planning horizon is reached.

Empirical Results

Table 1 presents the agricultural projections for Pinal County for ten year intervals from 1966 to 2006. Rows one through three give the actual reported acreages planted for the years

1966 and 1968, thus serving as a test of the predictive ability of the model.

The model was constructed in terms

of the cotton program in effect in

1966 with a lower allotment than in


In 1966, the upland cotton allotment was cut to 84,000 acres. Our projections for

1966 overestimated total cropped acres because, while in the model all readjustment occurred instantly, in actuality farmers take some time to adjust to a new equilibrium. The 1966 projections should be thought of as representative of the period 1966 -1976.

By 1968, readjustment is close to that projected.

Alfalfa is adjusting downward, grain sorghum is adjusting upward, and barley, wheat and miscellaneous field crops are equal to the projection. Since by 1968 the actual cotton allotment was raised above the constraints dictated by the 1966 program, upland cotton acreage in 1968 was higher than projected.

It ghum acres.

is doubtful that allotments can remain this high over time, however.

Downward adjustments in the cotton allotment would be reflected by increased grain sor-

We submit that the

model is closely reflecting actual farm adjustments.

Projected total cropped acres fall by

26.5 percent over the 40 -year period.

This is entirely because of rising water costs rather than from a physical shortage of water.

Less acres of the low valued crops will be grown. Acreage of high- valued crops, including cotton, vegetables and citrus, will not be affected.

Vegetables and citrus presently use only four percent of the county's irrigated acreage. They are mostly grown on specialty -type farms rather than


AGRICULTURE the general crop farms used in our model.

Since they can better afford high -priced water than can cotton, and cotton acreage is not affected b the price of water, acreage of th crops also will be independent of t ei falling water table.

Water use will fall by 27.2 percent during this period.

Use falls slightly faster than acreage because less water is used per acre as water costs rise and as the larger, more efficient farms grow a larger percent of total cropped acres.

Projected net income over variable cost drops by only 9.8 percent during the same period.

There are several reasons.

Adjustments in total acreage are entirely of low- valued crops which are even presently contributing little to net income. In 2006, a much larger proportion of the farms are large farms with lower costs of production. Finally, a larger proportion of total water use is from the small surface supply in the area.


Our projections imply that while the water table will continue to fall, the water- cost -increasing aspect of this decline will slow down the rate of future decline.

Net farm income in Pinal County will also decline in future years, but this decline will be gradual and of a relatively small m nitude.

Smaller farms will bear mo of the economic burden.

These projections suggest that so long as current cotton programs continue, the

economic impacts of continuing

groundwater withdrawal may not have as serious an impact as some have predicted.

Official Publication of the

College of Agriculture and

School of Home Economics

The University of Arizona






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