UNIVERSITY OF FLORIDA

AGRICULTURAL EXPERIMENT

STATION

REPORT FOR THE FISCAL YEAR ENDING
JUNE 30, 1926

CONTENTS
PAGE
REPORT OF DIRECTOR 5R
REPORT OF DIRECTOR ------------------------------------------------------ 5R
Introduction, 5R; Changes in Staff, 5R; Publications, 7R.
REPORT OF AUDITOR .................... ...................... 10R
REPORT OF AGRONOMIST ......--....---------------..............--- 13R
Greenhouse and Laboratory Additions, 13R; Enlargement of
Projects, 13R; Progress of Year's Work, 17R; Variety Tests,
17R; Winter Legume Tests, 18R; Crotalaria, 19R; Plant Breed-
ing, 19R; Fertilizer Experinients, 19R; Cover Crops and Green
Manure Studies, 20R; Crop Rotation, 20R; Peanut Fertilizer
Test, 20R; Pasture Grass Studies, 20R; Lawn:Grass Studies,
21R; Miscellaneous, 23R.
REPORT OF ANIMAL INDUSTRIALIST .............................................................. 24R
The Dairy Herd, 24R; Grapefruit Refuse as a Dairy Feed,
25R; Swine Feeding Experiments, 26R.
REPORT OF CHEMIST ---- --------- --------------------------- 29R
Dieback of Citrus, 29R; Nutrition Studies, 30R; Mineral Con-
tent of Grasses and Forage Crops, 32R.
REPORT OF COTTON INVESTIGATIONS ..............-...-.....---------.-------- 33R
Cotton Pathology and Physiology, 33R; Delinting Test, 33R;
Other Activities, 38R; Cotton Breeding and Variety Testing,
39R; Boll Weevil Investigations, 40R.
REPORT OF THE ENTOMOLOGIST ................................. .....-.- 42R
The New Citrus Aphid, 42R; Fumigation, 43R; Nematode Con-
trol, 44R; Thrips, 44R; Velvet Bean Caterpillar, 45R; Bean
Leaf-hopper, 45R; Life History Notes on the Citrus Aphid,
46R; Pecan Insects, 48R.
REPORT OF ASSISTANT HORTICULTURIST ..-............----.......-------..- 1R
Citrus, 51R; Berries, 51R; Pear, 53R; Miscellaneous Fruits,
53R; Grapes, 53R; Tung-oil, 56R; Improvements, 56R.
REPORT OF THE LIBRARIAN ............................................. .. 57R
REPORT OF THE PECAN CULTURIST .......................------- --- .................... 59R
Nut Growth, 59R; Variety and Stock Tests, 63R; Rejuvenation
Experiments, 64R; Rosette Experiment, 64R; Disease Control,
65R; Insect Control, 66R; Cover Crop, 67R.
REFORT OF THE PLANT PATHOLOGIST ..-............... .....------......- 68R
Citrus Canker, 68R; Melanose, 68R; Coloring of Citrus Fruits,
68R; Pecan Scab, 70R; Scaly Bark, 71R; Coconut Diseases,
73R; Truck Crop Diseases, 74R; Citrus Blight, 76R; Potato Dis-
eases, 78R; Strawberry Disease Work, 82R; Aphid Diseases,
84R.
REPORT OF THE VETERINARIAN ................................................................ 85R
Salt Sickness in Cattle, 85R; Manson's Eye Worm in Poultry,
87R; "Leeches" in Horses, 92R; Infectious Mastitis of Cattle,
93R; Diagnosis Work, 93R.
REPORT OF AGRICULTURAL ECONOMIST ........................................ 95R
REPORT OF HOME ECONOMIST ................................ .................................. 97R
Vitamine A, 97R; Nutritional Survey, 98R; Some Factors
That Influence Jellying, 98R; Canning of Non-acid Vegetables,
99R.
REPORT OF THE CITRUS EXPERIMENT STATION .......................................... 100R
Bud Supply Progeny Grove, 100R; Variety Grove, 100R; Root-
stocks Under Observation, 101R; Cultivation of Groves, 101R;
The Nursery, 101R; Dieback Grove, 102R; Agronomy Experi-
ments, 102R.
REPORT OF THE TOBACCO EXPERIMENT STATION.....--.......................... 105R
Fertilizer Experiments with Shade Tobacco, 105R; Fertilizer
and Variety Experiments with Bright Leaf Tobacco, 106R; To-
bacco Disease Investigations, 107R; Agronomic Work, 109R.
REPORT OF THE EVERGLADES EXPERIMENT STATION .................................. 112R
Buildings and Improvements, 112R; Investigational Work,
114R; Agronomic Work, 117R; Drainage Studies and Records,
123R; Livestock Diseases, 123R; Fires in the Everglades, 125R.

Hon. John W. Martin,
Governor of Florida,
Tallahassee, Florida.
SIR: I have the honor to transmit herewith the annual report
of the director of the University of Florida Agricultural Experi-
ment Station for the fiscal year ending June 30, 1926.
Respectfully,
P. K. YONGE,
Chairman, Board of Control.

BOARD OF CONTROL
P. K. YONGE, Chairman. Pensacola
E. L. WARTMANN, Citra
E. W. LANE, Jacksonville
A. H. BLENDING, Leesburg
W. B. DAVIS, Perry
J. T. DIAMOND, Secretary, Tallahassee
J. G. KELLUM, Auditor, Tallahassee

STATION STAFF
WILMON NEWELL, D. Sc., Director
JOHN M. SCOTT. B. S.. Vice Director and Animal Industrialist
SAM T. FLEMING, A. B., Assistant to Director
J. R. WATSON, A. M. Entomologist
ARCHIE N. TISSOT, M. S., Assistant Entomologist
H. E. BRATLEY, M. S. A., Asst. in Entomology
R. W. RUPRECHT, Ph. D., Chemist
R. M. BARNETTE. Ph. D., Assistant Chemist
C. E. BELL, M. S. Assistant Chemist
E. W. COWAN, A. M., Assistant Chemist'
J. M. COLEMAN, B. S., Assistant Chemist
0. F. BURGER, D Sc., Plant Pathologist
G. F. WEBER, Ph. D., Associate Plant Pathologist
J. L. SEAL, M. S., Assistant Plant Pathologist
ROBERT E. NOLEN, M. S. A., Lab. Asst. in Plant Pathology
K. W. LOUCKS, A. B., Lab. Asst. in Plant Pathology
ERDMAN WEST, B. S., Lab. Asst. in Plant Pathology
D. G. A. KELBERT, Field Asst. in Plant Pathology
W. E. STOKES, M. S., Agronomist
W. A. LEUKEL, Ph. D., Assistant Agronomist
A. F. CAMP, Ph. D., Associate Horticulturist
HAROLD MOWRY, Assistant Horticulturist
G. H. BLACKMON, B. S. A., Pecan Culturist
W. A. CARVER, Ph. D., Assistant Cotton Specialist
EDGAR F. GROSSMAN, M. A., Assistant Entomologist, Cotton Investigations
RAYMOND CROWN, B. S. A., Field Asst., Cotton Investigations
A. L. SHEALY, D. V. M., Veterinarian
D. A. SANDERS, D. V. M., Assistant Veterinarian
C. V. NOBLE, Ph. D., Agricultural Economist
BRUCE MCKINLEY, B. S. A., Assistant in Agricultural Economics
H. G. HAMILTON, M. S., Assistant Agricultural Economist
OUIDA DAVIS ABBOTT, Ph. D., Head, Home Economics Research
GEORGIA WESTOVER, Assistant in Home Economics
IDA KEELING CRESAP, Librarian
J. FRANCIS COOPER, B. S. A., Editor
RUBY NEWHALL, Secretary
HENRY ZEIGLER, Farm Foreman
W. B. TISDALE, Ph. D., Plant Pathologist, in charge Tobacco Experiment
Station (Quincy)
J. G. KELLEY, B. S. A., Field Assistant, Everglades Expt. Station, (Belle
Glade)
JESSE REEVES, Foreman Tobacco Experiment Station (Quincy)
L. O. GRATZ, Ph. D., Assistant Plant Pathologist (Hastings)
A. S. RHOADS, Ph. D., Assistant Plant Pathologist (Cocoa)
A. N. BROOKS, Ph. D., Assistant Plant Pathologist (Plant City)
STACY O. HAWKINS, Field Asst. in Plant Pathology (Miami)
J. H. JEFFERIES, Superintendent Citrus Experiment Station (Lake Alfred)
W. A. KUNTZ, A. M., Assistant Plant Pathologist (Lake Alfred)
GEO. E. TEDDER, Foreman, Everglades Experiment Station (Belle Glade)
J. H. HUNTER, M. S., Assistant Agronomist, Everglades Expt. Station,
(Belle Glade)

K. H. GRAHAM, Auditor
RACHEL MCQUARRIE, Assistant Auditor

Report for the Fiscal Year

Ending June 30, 1926

Hon. P. K. Yonge,
Chairman, Board of Control.
SIR: I have the honor to transmit herewith my report on the
work and investigations of the University of Florida Agricul-
tural Experiment Stations, together with the reports of the
heads of the several departments, for the fiscal year ending
June 30, 1926; and I request that you transmit the same, in ac-
cordance with law, to His Excellency, the Governor of Florida.
Respectfully,
WILMON NEWELL,
i, : Director.

INTRODUCTION
A summary of the activities of the Various departments in
the Experiment Station and Branch Stations is given in the fol-
lowing pages. i
The financial resources of the Experiment Stations for the
fiscal year just closed have been as follows:
Adams Fund .................- .......................$ 15,000.00
Hatch Fund ........... ........... ................... 15,000.00
Main Station, Gainesville ..................................... 182,106.50
Citrus Station .... -------............. -................- 14,575.00
Tobacco Station ............... ........................ 16,700.00
Everglades Station .....-....................... .. ......... 55,504.17
Special Appropriation, Labor ...............-............ 10,000.00
Station Incidental Fund .............-....- ..- .......... 11,568.63
Total ................. ...... .. ................ $320,454.30
Purnell Fund, not included above.......................... 18,266.67

CHANGES IN STAFF
Dr. A. F-.Camp was appointed Plant Physiologist in charge
of Cotton Investigations on July 1, 1925.
Dr. William A. Carver was appointed Assistant Cotton Speci-
alist on July 1, 1925.

Florida Agricultural Experiment Station

Dr. A. L. Shealy was appointed Veterinarian, in charge of the
Veterinary Department, on July 1, 1925.
Dr. D. A. Sanders was appointed Assistant Veterinarian on
July 1, 1925.
Dr. W. B. Tisdale, formerly Associate Plant Pathologist with
headquarters at the Tobacco Experiment Station, was appointed
Plant Pathologist in charge of the Tobacco Experiment Station
on July 1, 1925.
Dr. R. M. Barnette was appointed Assistant Chemist on Aug-
ust 1, 1925.
Dr. W. A. Leukel was appointed Assistant Agronomist on
August 15, 1925.
E. W. Cowan was appointed Assistant Chemist on September
1, 1925.
Archie N. Tissot was appointed Assistant Entomologist on
September 3, 1925.
D. G. A. Kelbert was appointed Field Assistant in Plant Path-
ology on October 1, 1925, with headquarters at Bradenton, Fla.
Edgar F. Grossman was appointed Assistant Entomologist, in
Cotton Investigations, on October 15, 1925.
Dr. Ouida Davis Abbott was appointed Head of Home Eco-
nomics Research work on November 1, 1925.
Stacy O. Hawkins was appointed Field Assistant in Plant
Pathology, with headquarters at Homestead, Fla., on December
10, 1925.
Bruce McKinley was appointed Assistant Agricultural Econo-
mist on January 1, 1926.
Miss Georgia Westover was appointed Assistant in Home Eco-
nomics on January 15, 1926.
J. H. Hunter was appointed Assistant Agronomist, with head-
quarters at the Everglades Station, on February 1, 1926.
M. A. Baker resigned as Field Assistant, Everglades Station,
effective February 5, 1926.
Sam T. Fleming was appointed Assistant to the Director on
March 1, 1926.
H. G. Hamilton was appointed Assistant Agricultural Econo-
mist on April 12, 1926.
Dr. C. V. Noble was appointed Head of the Department of
Agricultural Economics on May 10, 1926.

Annual Report, 1926

PUBLICATIONS

Following is a list of the publications issued by the Experi-
ment Station during the fiscal year ending June 30, 1926:

BULLETINS
No. Title Pages Edition
175 Factors Affecting Farm Profits in the Williston Area.. 20 10,000
176 Irish Potato Disease Investigations........................ 24 8,000
177 Diseases of Cucumbers ............................................ 48 10,000
178 Diseases of Grapes in Florida.......................................... 84 8,000
179 A Phytophthora Disease of Tobacco.............................. 64 3,000
180 The Mexican Cotton Boll Weevil ...................................... 32 10,000
181 Pecan Scab ...........--.......-............--........ 28 8,000
182 Stem Injury of Tobacco .................................... 12 3,000
183 Insects of a Citrus Grove ...................................... ..... 124 10,000
151 Florida Truck and Garden Insects (reprint)....................104 10,000

SUMMARY OF BULLETINS

No. 175, Factors Affecting Farm Profits in the Williston
Area. (J. E. Turlington and H. G. Hamilton), pp. 20, Fig. 1.
Reports results and conclusions drawn from a farm management
survey of 120 farms -in the Williston area for the year 1923.
Points out practices believed to tend toward a profit and those
believed to be unprofitable or only slightly profitable for farm-
ers in the Williston and similar areas, where cucumbers and
melons form the bulk of the crops grown.
No. 176, Irish Potato Disease Investigations, 1924-25. (A
preliminary report by L. O. Gratz), pp. 24, Figs. 6. Shows in
brief some of the existing problems and gives results of prelimi-
nary experiments conducted during the years of 1924 and 1925.
No. 177, Diseases of Cucumbers. (G. F. Weber), pp. 72,
Figs. 33. Information concerning the diseases that may attack
the cucumber plant. Discussion of the occurrence and seasonal
development of the diseases. A detailed description of each
disease is given, followed by control methods in each case.
No. 178, Diseases of Grapes in Florida. (Arthur S. Rhoads),
pp. 84, Figs. 40. Historical sketch of grape culture in Florida.
Climatic conditions of Florida in relation to those of other grape
growing sections. Basic principles in prevention of grape dis-
eases. Discussion of diseases due to parasitic fungi and bac-
teria, injuries due to physiological causes, and injuries due to
meteorological causes and animals. Showing, in each case, dis-

Florida Agricultural Experiment Station

tribution and importance, symptoms, causes, and measures for
control. Preparation of spray mixtures, stomach poisons, con-
tact poisons. Essential features of spraying outfits and spray
schedule.
No. 179, A Phytophthora Disease of Tobacco. (W. B. Tis-
dale and J. G. Kelley), pp. 64, Figs. 27. Description, history
and geographic distribution, and economic importance of the
disease. Investigational work with the fungus. Relation of
soil temperature to the development of the diseases. Control
experiments, including development of resistant strains of to-
bacco by selection.
No. 180, The Mexican Cotton Boll Weevil. (Wilmon Newell,
E. F. Grossman, and A. F. Camp), pp. 32, Figs. 7. Review of
history, biology and yearly cycle of the weevil. Presentation of
control methods now being used successfully so that the farmer
can estimate the value of the various methods suggested to him
and intelligently apply the method best suited to his particular
locality.
No. 181, Pecan Scab. (R. E. Nolen), pp. 28, Figs. 8. A
study of the fungus causing this disease, with introductory
statements relative to the geographical distribution of the dis-
ease, its economic importance, symptoms, etc. Susceptibility
and resistance in varieties of the host, and climatic relations.
No. 182, Stem Injury of Tobacco. (W. B. Tisdale and J. G.
Kelley), pp. 12, Figs. 6. A discussion of stem injury caused by
fungi growing on the poison mixture used for controlling bud-
worms, with suggestions for control.
No. 183, Insects of a Citrus Grove. (J. R. Watson), pp. 136,
Figs. 87. This bulletin describes insect pests in Florida citrus
groves, gives an account of their life history and states the best
methods for their control. Formulas for the common insecti-
cides are included.
No. 151, Florida Truck and Garden Insects. (J. R. Watson),
pp. 104, Figs. 57. A reference bulletin for Florida truckers
and kitchen gardeners, giving the description, with illustration,
the life-history, and a statement of the best methods for the
control of the insects and pests which commonly trouble them.

Annual Report, 1926

PRESS BULLETINS
NO. Title Author
369 Starve Out the Citrus Aphis This Winter.............-..............J. R. Watson
370 Moles ...................................................... .........--- J. R. W atson
371 The Chinch Bug on St. Augustine Grass Lawns................----- R. Watson
372 Mole-Crickets ...-..............................- -.... ...-- ......------.....-... R. W atson
373 Spray Schedule for Peaches:.................J. R. Watson & Carl B. James
374 Push Out the Spring Growth to Avoid Aphis Injury........J. R. Watson
375 Stamp Out the Citrus Aphis During the Winter................J. R. Watson
376 Fumigation of Citrus Trees ................................................... R. Watson
377 Disinfecting Truck Crop Seed with Corrosive Sublimate....G. F. Weber
378 Propagating Citrus Nursery Stock ......................----- --.............. E. L. Lord
379 Transplanting Pecan Trees .............................................G. H. Blackmon
380 Pecan Soils .........................-------................ -----... G. H. Blackmon
381 Pecan Scab Control ............................................................G. H. Blackmon
382 Bulbs in Florida ..................---.....................----- ..-- .Harold Mowry
383 Propagation of Guavas ....................................................Harold Mowry
384 Asparagus Plumosus .................-...................-........................Harold Mowry
385 Propagating and Transplanting Palms ............................Harold Mowry
386 Papaya Culture .... .......................................................Harold Mowry
387 Bulletin List.
388 Fertilizers for Pineapples ............................................... W. Ruprecht
389 Lawns in Florida ...................--.......................................W. E. Stokes
327 How to Poison Ants (reprinted) .......................................... J. R. Watson
334 Red Rot of Sugar Cane (reprinted) ..----.................................0. F Burger
345 Controlling Poultry Lice (reprinted) ..................................J. ..R. Watson
377 Disinfecting Truck Crop Seed With Corrosive Sublimate
(reprinted) .. --.--...--------- ..................................... G. F. Weber

10R Florida Agricultural Experiment Station

REPORT OF AUDITOR

Wilmon Newell, Director.
SmI: I submit the following report of the credits received
and expenditures vouchered out of various Experiment Station
funds for the year ending June 30, 1926.
Respectfully,
K. H. GRAHAM,
Auditor.

MAIN EXPERIMENT STATION, 1925-1926
RECEIPTS
State Appropriation, Biennium 1925-27 (including $22,400
spent for purchase of additional land) .........................................$182,106.50
EXPENDITURES
Salaries ........-------.....-----.....- ............................... .$59,819.22
Labor .................................................................................. 20,154.62
Stationery and office supplies ........................................ 1,405.24
Scientific supplies, consumable .................................... 4,116.01
Feeding stuffs ........---..............- --..-- ...... .............. 2,231.88
Sundry supplies .................................................................. 3,577.09
Fertilizer ........................................ .. .. ...---- -...... 3,192.12
Communication service .................................................... 1,809.92
Travel expense ............................................. ..... ... 11,768.93
Transportation of things ..................................... ... 1,394.52
Publications ................... .. ........ ..... .......... 6,861.91
Heat, light, water, power ............................ 1,045.36
Furniture, furnishings and fixtures ...------....------- 3,966.67
Library ............................ ..................... 5,103.13
Scientific equipment .......................................... . 4,036.37
Livestock .---- ......-. -- ---------------------.. 79.00
Tools, m achinery ......................................................... 2,678.41
Buildings and land .............................. ....... ......... 44,524.87
Contingent ........................................................................ 838.79
Balance ............--....... ..... .............................. ........ ........ 3,502.44
$182,106.50

SPECIAL APPROPRIATION, MAIN STATION FUND, 1925-1926
RECEIPTS
State Appropriation, 1925-27 ............ ........ ......................................$10,000.00
EXPENDITURES
Labor .............. ......... .... ........... ..... $ 1,365.12
Balance -........ ......... ................................. 8,634.88
$10,000.00

Annual Report, 1926 11R

STATION INCIDENTAL FUND, 1925-1926
RECEIPTS
Balance, 1924-25 ................ ...........-..........---....-.........-- $ 1,864.04
Receipts, 1925-26 .................................-................. ..... 9,704.59

$11,568.63
EXPENDITURES
Salaries ........................................ ...........-....... $ 300.00
Labor ...........................--....... .. --------------.......-... 338.45
Stationery and office supplies ............................... ......
Scientific supplies, consumable ........................................ 132.22
Feeding stuffs .................. ....... ......... ............... 7,737.05
Sundry supplies ....................................... ....-- -- .-- ..-- 196.90
Fertilizers ................................ ........................................ 136.00
Communication service ....................................-........-- 11.93
Travel expense ..................------ ..... ---.................- -...-.--10.30
Transportation of things --.....................................--..------- 40.92
Heat, light, water, power ...........................--- ........... -- 93.00
Furniture, furnishings ......-...................- ..........-....... 3.00
Library ..........................---- .....------ -.....- -.............. 2.55
Scientific equipment ............................ .......--..--.......... 130.61
Livestock ....................................... .. .......-.......... 14.00
Tools, machinery and appliances .................................. 140.53
Buildings and land ............................... ............ ........ 106.63
Contingent ............................. .............-.......-............. 9.16
Balance ............................. ...--------- -...........--. 2,165.38

$11,568.63

CITRUS EXPERIMENT STATION FUND, 1925-1926
RECEIPTS
State Appropriation, % Biennium 1925-27----...................................-- $14,575.00
EXPENDITURES
Salaries ............................. ..... ................ ... ..... ....... $ 2,400.00
Labor ......................... ................... ................................. 1,964.23
Stationery and office supplies ........................................ 7.45
Scientific supplies, consumable .................--................... 11.48
Feeding stuffs ..................................----............----------....- 430.33
Sundry supplies .........................-......................---... 298.59
Fertilizers ................................--- -- ...--..--.--- ....-..--- ... 283.40
Communication service ...........................-- ...----........ --26.59
Travel expense ..................-......... ..-------....-..---........ 239.79
Transportation of things .........................--- ............ 26.24
Heat, light, water, power ................-......--.--........-.. 71.55
Furniture, furnishings and fixtures ....................--.....-- 1.35
Library ................................-.... --..-.........- ....-- ... 6.75
Tools, machinery and appliances .................................. 290.90
Buildings and lands .......................... ............... ........ 2,374.77
Contingent .................................................. .........-------- 27.55
B balance ............................................................................... 6,114.03

$14,575.00

12R FloWda Agricultural Experiment Station

TOBACCO EXPERIMENT STATION FUNDS, 1925-1926
RECEIPTS
State Appropriation, % Biennium 1925-27................................---$16,700.00
EXPENDITURES
Salaries ......--.. ............--..............................------ ---$ 6,750.00
Labor ...-..----.........................- ....................... --------- 1,127.44
Stationery and office supplies ...................................... 65.86
Scientific supplies ..................------ ......----------- ... 172.46
F eeds ............................................... ................................ 235.56
Sundry supplies .........------....................-.... ... 455.63
Fertilizers ...-----..-.. --...------......----- ------ 456.96
Communication service ..............-.....- ................... 63.85
Travel ...........................----...... -------...............------- 318.15
Transportation of things ................-..-..............-.... ... 90.04
Heat, light, water and power ....--------.........-- .....--- .. 192.75
Furniture, furnishings and fixtures .............- -----... 194.03
Library ....--------.......................... ................... .. 179.84
Scientific equipment .....-------......-... ........--------- ....--- .. 191.74
Tools, machinery and appliances .................................... 244.60
Buildings and lands (inc. repairs) ................................ 2,174.70
Contingent expense ..........................- .. .......-.... ... 159.21
Balance ...............................................----....................-... 3,627.18
$16,700.00

EVERGLADES EXPERIMENT STATION, 1925-1926
RECEIPTS
Balance 1924-25 ......... -------....... ---..-................................ $ 5,504.17
State Appropriation, Chapter 11,332, Biennium
1925-27 -----................................................. 45,000.00
State Appropriation, Chapter 8442 ............................. 5,000.00
$55,504.17
EXPENDITURES
Salaries .....................--. ...-------- --......- ........................$- 6,065.00
Labor .................................................. ........................... 12,657.58
Stationery and office supplies ........................................ 190.05
Scientific supplies, consumable ...................................... 24.28
Feeding stuffs ......................................... ....................... 140.21
Sundry supplies ...................................----------------------.... 1,468.45
Fertilizers --..... --- -----................................... .....--------...... 49.60
Communication service ....................---.--...----------..... 75.37
Travel expense ........................................................... 1,244.52
Transportation of things ................................................ 426.03
Heat, light, water and power ....................................... 2,008.34
Furniture, furnishings and fixtures .............................. 692.69
Library .............................................................................. 20.00
Scientific equipment .................................................. 346.39
Livestock ............................................................................ 250.00
Tools, machinery and appliances .................................. 2,693.22
Buildings and land ........... ................................... 20,075.88
Contingent ......................................................................... 84.30
Balance ...... .........................-.......................-..................... 6,992.26
$55,504.17

Annual Report, 1926

REPORT OF AGRONOMIST
Wilmon Newell, Director.
SIR: I submit the following report for the Department of
Agronomy for the fiscal year ending June 30, 1926.
Respectfully,
W. E. STOKES,
Agronomist.
As last year, the investigational work of the department has
been carried on in cooperation with the Office of Forage Crop
Investigations of the Bureau of Plant Industry of the United
States Department of Agriculture.

GREENHOUSE AND LABORATORY ADDITIONS
A heating system has been installed in the agronomy and
chemistry greenhouse and a solution balance obtained. Enough
glazed earthernware pots were purchased to pursue controlled
greenhouse pot work.
A grinding room with electric motor and mills for grinding
samples for plant analysis has been equipped in cooperation with
the Chemistry and Home Economics departments.
A small chemical laboratory in the basement of the Experi-
ment Station Building has been equipped for plant analysis in
connection with new phases of the work with pasture grass
and green manure studies.

ENLARGEMENT OF PROJECTS
No entirely new projects have been started, but enlargements
of the cover and green manure project and the pasture grass stu-
dies have been made as follows:

PASTURE GRASS STUDIES
In addition to the field and plot experiments on pasture grasses
given in this and previous reports, a more detailed study is being
made on the growth and physiological behavior of these grasses.
Recent investigations on vegetation and reproduction in plants
have shown that different stages of growth are associated with a
certain relation between the carbohydrate and nitrogen com-
pounds. High carbohydrates in relation to nitrogen are asso-
ciated with reproduction, while low carbohydrates in relation.to
nitrogen in plants are associated with vegetative growth. An

13R

Florida Agricultural Experiment Station

increase in carbohydrates is brought about thru increased leaf
area for photosynthetic activity while lower carbohydrates occur
with decreased leaf area. Under grazing the leaf area of the
individual plants is kept at a minimum, and therefore carbo-
hydrates are generally low or a narrow carbohydrate-nitrogen
ratio obtains. The narrow carbohydrate-nitrogen ratio keeps
the sod forming grasses in Florida in a vegetative stage of
growth and as a result a dense sod is formed. When grasses are
not grazed, a larger leaf area is formed on the individual plants
and a wide carbohydrate-nitrogen ratio obtains, which is associ-
ated with reproduction in the plants and a retardation of vege-
tative growth and a thin sod. To determine this carbohydrate-
nitrogen relation in these grasses and its effect on their sod
forming habits, more detailed experiments have been under-
taken as follows:
From an established sod, samples of grasses (Bahia and car-
pet) are being dug from grazed and ungrazed areas at definite
intervals and analyzed for the different nitrogen and carbohy-
drate compounds. A difference in the relation between these
carbohydrate and nitrogen compounds should obtain in the plants
of the grazed area from that of those in the ungrazed area.
A more detailed experiment with transplanted carpet and
Bahia grasses is under way. These grasses are transplanted in
rows. Half the rows are to be mowed and the remainder al-
lowed to grow to maturity. Samples are to be taken at definite
intervals from the mowed and unmowed areas and analyzed for
the different carbohydrate and nitrogen compounds. Soil
samples taken at definite intervals of time are to be analyzed
for total and nitrate nitrogen and the results correlated with
the growth of the plants. The difference and variation in the
nitrogen-carbohydrate relations in the plants in the mowed and
unmowed areas correlated with the difference in the spread
and sod formation in these different areas should give us worth
while information in regard to the treatment and management
of these pasture grasses.

GREEN MANURES
A more intensive study is being made of the different cover
and green manure crops now used in field investigations. These
studies are being carried out with the idea in view of correlating
the composition of the plant with its decomposition in the soil.

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Annual Report, 1926

Necessarily, this project is a cooperative one between the de-
partments of Agronomy and Chemistry.
Such intensive work should lead to: (1) The variation of the
composition of the plant at different stages of growth; (2) the
correlation of the composition of the plant at its various stages
of growth with its decomposition in the soil, leading ultimately
to a better understanding of the energy furnished for the micro-
organisms by the plants at different ages; (3) a study of the
humus complex formed upon the decomposition of the plant.
These studies are to be conducted with both leguminous and
non-leguminous cover crops, the idea being to ascertain if the
carbohydrate-nitrogen relation in the different plants and at
the different stages of growth has an influence on the ultimate
nature and amount of the humus complex formed in the soil.
The ultimate aim of the experiment is to obtain a humus complex
which will offer the greatest resistance to rapid decomposition in
Florida soils and which at the same time has the desirable prop-
erties of fixing large amounts of plant nutrients.
To correlate this variation in the composition of the plant at
various stages of growth with its decomposition in the soil, three
series of pot experiments were started under greenhouse con-
ditions. The pots in each series contain a definite weight of
sandy soil low in humus, nitrogen, and carbonates. Crotalaria
striata plants are grown in the soil in each series as a green
manure crop. In one series the plants are harvested at definite
periods of growth and analyzed for nitrogen and carbohydrate
compounds. Soil samples are taken after each harvest and
analyzed for the various forms of nitrogen. In another series
the plants are turned under at each of the various stages of
growth and subjected to leaching at definite intervals during
a period of four to six months (decomposition period). Analyses
are made of the total nitrogen and nitrate nitrogen in the leach-
ings. Total nitrogen and total carbon are determined on dried
soil samples taken at the end of each decomposition period
(which must be the same for each series). In the third series,
plants are turned under at the above stated intervals, but not
subjected to leaching. Soil samples taken at the end of each
decomposition period are analyzed for total nitrogen, nitrate
nitrogen, and total carbon.
At the end of the decomposition periods in each series, a speci-
fied economic crop is to be planted in the pots of the three series.

Florida Agricultural Experiment Station

The variation in growth and amount of plant material produced
from the soil in each series will indicate in terms of plant growth
the beneficial or detrimental effects of each soil treatment. A
study and correlation of data obtained from the various analyses
of the nitrogen and carbohydrate compounds in the plants at
various stages of growth and in the soil resulting from the dif-
ferent treatments given should show a marked relation between
the variation in the composition of the plant at various stages of
growth and its decomposition in the soil. Data obtained thus far
indicate such a relation.
The above preliminary experiment is to be followed by others
on a larger scale in lysimeters and also under field conditions.
Another phase of work with Crotalaria has been undertaken
in regard to the stage of growth at which the plant should be cut
so as to produce a vigorous aftergrowth that will produce seed
for the next season's volunteer crop, leaving the first cutting on
the ground as a mulch for the orchard. Recent investigations
with alfalfa and sweet clover have shown that new top growth
is produced at the expense of the previously deposited reserve
organic foods in the plant when a cutting is made. These reserve
foods in the storage regions of the plant are replenished when
the top growth of the plant is of sufficient size and maturity to
elaborate organic foods in excess of those needed for growth and
maintenance. These excess foods are again stored in the plant
for further new growth.
To determine at what stage of growth the Crotalaria plant con-
tains a sufficient percentage and quantity of organic foods in its
roots and stems for production of a vigorous second top-growth
after being cut, the following experiment is being conducted:
Plants are cit in the various stages of growth at two different
-heights 'iiich and 8 inches from the surface of the ground.
Samples of the roots and part of the stem left on the plant are
preserved for analysis of organic foods stored therein. These
:treatments apply to plants grown from seed under field condi-
tioni. The aftergrowth froni the plants cut at the various stages
of growth is to be correlated with the percentage and quantity
of organic foods stored in the roots of the plant when the first
top cutting was made.
A similar experiment is to be carried out another season with
transplanted Crotalaria plants under more uniform conditions
for growth. A proper correlation between the stored organic
foods in the plant with the behavior and quantity of second

16R

, Annual Report, 1926

growth should give worth while information in regard to the
time and stage for cutting these plants in orchards for the best
second growth.

PROGRESS OF THE YEAR'S WORK
During the year, seed and vegetative material of 114 different
species of possible forage plants were received from the Office
of Forage Crop Investigations of the Bureau of Plant Industry
of the United States Department of Agriculture for trial. Of
this-lot of material, 67 were grasses and 47 legumes. All of this
material was planted either in greenhouse, grass garden, or plot
fields for study.
Crops tested for silage this year on Norfolk sandy soil were
corn, sorghum, Japanese cane, and Napier grass. As last year,
Napier grass gave the highest yield, followed by Japanese cane,
sorghum and corn, in the order named.
The test of Japanese cane and Napier grass irrigated with
overflow from the university septic tanks, irrigated with city
water, and no irrigation was brought to a close at the end of the
1925 growing season. The results confirm those of the previous
year as reported in the 1925 annual report. The work will prob-
ably be reported in detail in bulletin form later.

VARIETY TESTS
The sorghum variety test for 1925 included 20 varieties grown
on Norfolk sandy soil. The highest yielding variety was Sacca-
line sorghum S. P. I. 48191, which produced 18.3 tons of silage
per acre at the first cutting and 4.4 tons of silage per acre at
the second cutting.
Corn variety test work was continued. In the test were seven
Florida corns, three Southeastern corns, and one Northern corn
that is commonly sold in Florida. Hastings' Prolific gave the
highest silage yield, 10.6 tons per acre, followed by Tisdale,
Smith, Wilson Yellow Dent, and Cuban Flint in the order named.
Kilgore's Red Cob gave the highest yield of shelled corn per acre,
41.6 bushels, followed by Hastings' Prolific, Tisdale, Smith, and
Wilson Yellow Dent in the order named.
PEANUT VARIETY TEST
Peanut variety test work was continued, 13 varieties, strains,
and selections being in the test. No fertilizer was used, but
gypsum (land plaster) applied at blooming time to half of

17R

Florida Agricultural Experiment Station

each variety test plot continues to give increases in yield in most
instances, and in some instances, very striking increases, par-
ticularly with the large seeded types.

OAT VARIETY TEST
The following varieties and strains of oats were grown in the
variety test on Norfolk sandy soil at the Main Experiment Sta-
tion at Gainesville: Fulghum C. I. 699-2011, Red Rust Proof C. I.
1815, Silvermine C. I. 659, Fulghum C. I. 708, Richland C. I.
787, Swedish Select C. I. 134. Fulghum C. I. 699-2011 yielded
highest, followed by Red Rust Proof C. I. 1815.

SOYBEAN VARIETY TESTING WORK
The soybean variety test work at the Experiment Station, in
which eight varieties were planted, indicated that Otootan,
Laredo, Biloxi, and Mammoth Yellow are our most promising
varieties so far tested. In five of the nine counties where hay
yields of soybeans were obtained, the Otootan variety gave the
highest yield. No satisfactory records of seed yields were ob-
tained except in Escambia County, and here Laredo gave the
highest yield, 13.87 bushels per acre. Soybean variety tests are
being conducted in eight counties of North Florida this year.

WINTER LEGUME TESTS
The following legumes were inoculated and planted on Norfolk
sandy soil: Hairy vetch, bitter vetch, Hungarian vetch, Austrian
winter field pea, bur clover, crimson clover, annual yellow sweet
clover, and serradella. None made a satisfactory growth.
The following alfalfas were received from the Bureau of Plant
Industry and planted in the fall of 1925: Hairy Peruvian No.
583, India No. 1724, Smooth Peruvian No. 2274, Utah No. 2561,
Spanish No. 2005, Kansas No. 533, Italian No. 2004, Argentine
No. 2538. None made a satisfactory growth even where lime
was used. Kansas No. 533 made the most promising growth.
Hairy and common or Oregon vetch planted in Duval County
on Norfolk fine sand in a bearing pecan grove made a very satis-
factory growth, especially the hairy vetch.
The following legumes were inoculated and planted on Bladen
fine sandy loam soil (flatwoods land) in Duval County in a
pecan grove: Crimson clover, Southern bur clover, hairy vetch,
Hungarian vetch, Oregon vetch, Austrian field peas, and serra-

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Annual Report, 1926

della. None made an entirely satisfactory growth, tho all except:
crimson clover and serradella made a promising growth. Volun-
teer crops of black medic (Medicago lupulina) and Hubam and
annual yellow sweet clover were good where the land was culti-
vated in early fall. The volunteer crops were poor on land not
cultivated after the original crop had died. None of the vetches
or winter field peas planted in the fall of 1924 gave a volunteer
crop of any consequence.

CROTALARIAS
A number of species of Crotalaria were under observation at
the Experiment Station during the year. Crotalaria striata and
Crotalaria sericea continue to be the two most promising kinds.
Hay made from Crotalaria was fed to a cow for 33 days, and
to a mule for a shorter time, without any apparent bad effects.
It was necessary to partially starve these animals into eating
Crotalaria at first.
High mowing of Crotalaria, eight to ten inches, continued to
give a better second growth than lower mowing.
Date of seeding test with Crotalaria indicates that satisfactory
stands can be obtained, provided moisture is sufficient, any time
from early spring until mid-summer.

PLANT BREEDING
The breeding work with Spanish peanuts was continued dur-
ing the year with good results. The 100 selections started with
in 1920 have been weeded down to nine now, and increase blocks
were planted this year so as to increase the supply of seed of
some of the highest yielding strains. Further testing of later se-
lections of Spanish peanuts has been carried out this year.

FERTILIZER EXPERIMENTS
The fertilizer work with Spanish peanuts in a rotation with
corn and velvet beans was continued during the year with vir-
tually the same results as reported in the previous annual report.
Ground limestone continued to show bad results with peanuts,
corn, and velvet beans on Norfolk sand. This experiment will
probably be presented in bulletin form shortly. Pots have been
secured for a greenhouse study of the limed area to learn some-
thing about why crop yields have been decreased by liming.

19R

Florida Agricultural Experiment Station

COVER CROPS AND GREEN MANURE STUDIES
In the cover crop and green manure studies, Crotalaria contin-
ues to yield more pounds per acre of material to turn back to the
soil than does cowpeas, beggarweed, or velvet beans on Norfolk
sandy soil. Sweet potatoes following Crotalaria turned under
gave a much higher yield than sweet potatoes following any of
the other legumes. Corn following Crotalaria turned under did
not give quite as high a yield as corn following velvet beans turned
under.
Cover crop and green manure studies were started at the
Citrus Experiment Station at Lake Alfred, the object being to
compare cowpeas, beggarweed, velvet beans and Crotalaria as
cover and green manure crops in a citrus grove, their value to be
measured by growth of trees and quantity and quality of fruit
produced following the growing and turning under of the legumes
compared to trees grown on land where non-leguminous cover
crops as well as no cover crops are used.

CROP ROTATION STUDIES
Crop rotation work started in 1924 was continued, but this
work has not been in progress long enough to show any con-
clusive results, since the three-year cycle has not yet been com-
pleted.

SYSTEMATIC PEANUT FERTILIZER EXPERIMENT
The regular systematic fertilizer experiment with Spanish
peanuts, started in 1922, on Norfolk sandy soil, was continued.
No fertilizer treatment has so far materially increased yields,
altho a slight increase in yield is indicated with some treatments.
Gypsum gives a slight increase in yield in some instances, but
hardly enough so far to make it profitable to use on Spanish
peanuts.
PASTURE GRASS STUDIES
The pasture experimental work, as outlined in previous annual
reports, was continued and, in addition, some fertilizer experi-
mental work with pastures was started in Duval and Alachua
counties. This preliminary work indicates that it is probably
going to pay to apply some fertilizer to our pastures, especially
to young pastures just getting established, since an application
of 100 pounds of acid phosphate, 50. pounds of nitrate of soda,

20R

Annual Report, 1926

and 25 pounds of muriate of potash per acre, mixed, gave a
marked increase in growth of a young pasture composed of car-
pet grass, Dallis grass and lespedeza on Bladen fine sandy loam
soil in Duval County and the same kind of pasture on Portsmouth
soil in Alachua County.
Fifteen acres have been seeded to five different kinds of
pasture plants in order to get data on carrying capacity and for-
age value. The grasses used were carpet, Dallis, Bahia, Ber-
muda and a mixed planting of these four.
As mentioned under changes in projects, studies have been
started on the growth and physiological behavior of pasture
grasses. To what extent sod forming grasses should be grazed
so as to bring about the most rapid spread and forming and
maintaining of dense sod can probably best be learned thru a
physiological and biochemical study of these plants in connec-
tion with different methods of handling the pastures.
Green and dry weights of mowings of 14 pasture grasses un-
der irrigation were obtained. The grasses were mowed 20 times
from June 3 to November 18, and Dallis grass (Paspalum dila-
tatum) gave the highest yield of green and dry material per
acre, followed by centipede grass (Eremochloa ophiuroides).
This does not give grazing data, but is the nearest approach to
it until such time as money and land are available for getting
these grasses out on large enough areas to actually graze them.
Centipede grass (Eremochloa ophiuroides) continued to show
up as the most promising new pasture grass under observation.
A preliminary study of the root system of sod forming grasses
has been started. Bermuda, carpet, Bahia, St. Augustine, centi-
pede, and Dallis grasses all send a mass of fibrous roots down to
a depth of three to four feet. The depth and density of the root
systems seem to vary with the different grasses and with the
same grass on different soils and the manner of management of
the soil and grass.
Thoro preparation of land previous to seeding continues to
give better stands and growth than poor or no preparation previ-
ous to seeding.
LAWN GRASS STUDIES
Fifteen different kinds of grasses were under observation in
the lawn test plots. St. Augustine, centipede (Eremochloa ophi-
uroides), Japanese lawn grass (Osterdamia japonica), Manila

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Florida Agricultural Experiment Station

Fig. 1.-Root systems of grasses, showing effect of soil type and manage-
ment. All plants shown are one year old. The two plants on the left
are Atlanta Bermuda, which have been mowed frequently. The plant on
the extreme left was in clay soil, the next one in sand. The two plants
on the right are Bermuda which have been grown on the same soil
type. The one on the extreme right has been mowed occasionally to
keep the grass from seeding. The other has never been mowed.

grass (Osterdamia matrella), Mascarene grass (Osterdamia ten-
uifolia), Bermuda grass, and carpet grass seem superior. St.
Augustine and centipede grasses were outstanding.
Studies looking toward the control of weed growth by the fre-
quent use of ammonium sulfate and ammonium phosphate were
continued, but nothing definite has come out of these studies
as yet, altho the pH value of the soils of that part of the lawn
plots fertilized with ammonium sulfate and ammonium phos-
phate has apparently started to come down.

WORK AT THE BRANCH EXPERIMENT STATIONS
Report of the work at the Branch Experiment Stations will be
found under the reports of these respective stations.

22R

Annual Report, 1926 23R

MISCELLANEOUS
Many plant identifications have been made for correspondents,
and much material has been distributed for testing. Corre-
spondence relative to farm crops has greatly increased over last
year; so much so that a full time stenographer was employed,
beginning June 1, 1926.

Florida Agricultural Experiment Station

REPORT OF ANIMAL INDUSTRIALIST
Wilmon Newell, Director.
SIR: I submit the following report of the Animal Industrialist
for the fiscal year ending June 30, 1926.
Respectfully,
JOHN M. SCOTT,
Animal Industrialist.

THE DAIRY HERD
There has been but little change in the dairy herd during the
year. Bull calves from the best producing cows have been sold
to dairymen and farmers of the state. Heifer calves from only
the best producing cows in the herd have been retained to replace
the old cows and poorer producers. The herd is now large
enough that a good system of culling can be put into practice.
During the year five cows were on register of merit test. These
five cows were bred and raised on the Experiment Station Farm.
Two of these cows were sired by Prince Landseer Tormentor
130913, and three by Florida's Majesty 153431. These two bulls
have done much to increase the production of the herd.
Majesty's Fairy Pogis 491756 started on test March 15, 1925,
and continued on test for 365 days, until March 14, 1926. During
the year she produced a total of 10,696 pounds of milk averaging
4.72 percent fat, and a total of 504.65 pounds of fat. Landseer's
Florida Queen also was on test for one year, beginning April 1,
1925, and ending March 31, 1926. She produced 13,354 pounds
of milk which had an average butterfat test of 4.45 percent, giv-
ing her 594.67 pounds of butter for the year. Majesty's Noble
Lassie 492336 went on test May 1, 1925, and her test was ended
after 365 days on April 30, 1926. She produced 9,660 pounds of
milk testing 4.63 percent butterfat, giving a total of 447.82
pounds of fat. Majesty's Landseer's Belle 491757 was put on
test June 16, 1925, and kept on test until June 15, 1926. Her
production was 9,439 pounds of milk testing 5.24 percent fat,
her total butterfat production for the 365 days being 494.41
pounds. Landseer's Florida Jewel 421940 was on test for 305
days, beginning July 25, 1925, and ending May 7, 1926. Her rec-
ord was 7,891 pounds of milk, 4.92 percent fat, and 388.32 pounds
of butterfat.

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Annual Report, 1926

TABLE I.-MILK RECORD OF DAIRY HERD, JULY 1, 1925, TO JUNE 30, 1926

Cow No.

53

59

81

85

98

118

120

141

152

153

155

163

171

172

175

213

219

220

225

228

231

Days Pounds
in Milk of Milk

223 4,208.3

272 4,074.3

297 5,512.4

264 4,058.2

266 6,150.3

274 9,519.2

305 7,887.0

301 5,144.0

307 7,656.2

315 9,131.6

350 8,957.9

329 5,350.0

320 4,420.2

318 4,446.3

322 5,626.7

282 4,368.8

113 2,367.4

177 3,108.0

312 5,628.9

91 1,713.6

229 4,494.3

Percentage
of Butterfat

4.3

4.3

4.3

4.2

4.8

4.7

4.9

4.2

4.0

5.1

5.2

4.5

5.4

5.0

5.3

5.0

3.3

3.6

5.4

5.6

5.1

GRAPEFRUIT REFUSE AS A DAIRY FEED
Ever since the canning of grapefruit became an industry in
Florida, there has been more or less demand for information as
to the value of the refuse from the canning factories as a feed
for livestock. The Florida Citrus Exchange supplied us with a
quantity of the dried grapefruit refuse. This material was used
in the dairy to determine its value as a milk producer and to
study its effect on the animals to which it was fed.
Six cows were selected for the experiment. These were divided
into two lots of three cows each. The reversal method of feed-

Pounds of
Butterfat

183.4

175.7

238.0

171.0

301.2

446.9

388.0

217.5

307.0

469.9

474.3

241.3

240.0

225.3

298.5

219.3

78.4

112.2

304.8

86.8

231.1

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26R Florida Agricultural Experiment Station

ing was used. All cows were fed the same grain ration, the only
difference being one lot received the grapefruit refuse in addition
to the grain rations.
It will be seen from Table II that the grapefruit refuse seemed
to have a tendency to increase the milk flow. Additional tests
should be conducted before definite conclusions can be drawn.
TABLE II.-MILK RECORD OF COWS IN EXPERIMENT TESTING VALUE OF
GRAPEFRUIT REFUSE AS DAIRY FEED. (SAME GRAIN RATION FED
TO ALL COWS.)
May, 1925
All cows fed alike.

Cow No. Pounds Milk
98............................... 384.4
136.........................-- ..... 483.6
191................................ 309.4
1,177.4

No grapefruit refuse fed
98................................ 376.0
136...............................-----. 467.5
191................................ 283.5
1,127.0

June, 1925

Cow No. Pounds Milk
53................................ 329.3
81................................ 404.5
141.............................. 562.3
1,296.1

Fed grapefruit refuse
53................................ 398.4
81..........-- ---...................... 457.9
141................................ 600.0
1,456.3

July, 1925
Fed grapefruit refuse No grapefruit refuse fed
98-- ------............................ 401.8 53.. -------.............................. 363.3
136................................ 538.0 81.............................--..---- 382.9
191................................ 341.3 141--------................................ 636.4
1,281.1 1,382.6
The above figures indicate an increased milk yield when grape-
fruit refuse is fed. The following is the analysis of grapefruit
refuse, as found by the Chemistry department of this station:
Moisture ....................................... ..18.00 percent r ,_
Fat ..--.. --.... ---------.......... 5.25 percent
Protein .................................. ...... 5.31 percent
Carbohydrates ....................................61.69 percent.' + -
Fiber ................... ........ ................. 9.75 percent

SWINE FEEDING EXPERIMENTS
The swine feeding experiments during the year were a com-
parison of two rations for economical pork production:
(1) Shelled corn and fish meal.
(2) Shelled corn, alfalfa meal, and cottonseed meal.
In all of the experiments the feeds were fed in the following
proportions by weight:
(1) Corn nine parts; fish meal one part.
(2) Corn nine parts; alfalfa meal two parts; and cottonseed
meal one part.

Annual Report, 1926

Three experiments were conducted during the year in which
48 hogs were used. In the first experiment, 14 hogs were used,
divided into two lots of 7 each; in the second experiment, 20 hogs
were divided into two lots of 10 each; in the third experiment, 14
hogs in two lots of 7 each were used.
All weighing were made on three consecutive days and the
average of the three taken as the weight. The lots were weighed
at the beginning and again at the close of the experiment.
The cottonseed meal used in all of the experiments was the
bright meal with an anaylsis of 7 percent ammonia. The alfalfa
meal used was fine ground choice pea green. The fish meal was
pure ground fish meal which analyzed 55 percent protein, 4 per-
cent fats, 2 percent fibre, and 15 percent mineral matter.
The following tables give the weights, gains and amount of
feed required to make 100 pounds of gain.

TABLE III.-RESULTS OF FIRST EXPERIMENT TESTING VALUE OF ALFALFA
MEAL AND COTTONSEED MEAL AS COMPARED TO FISH MEAL AS A HOG
FEED. (SEVEN HOGS IN EACH LOT.)
FEEDS CONSUMED Lot I Lot II
Pounds Pounds
Shelled corn .......................................... 1,651.5 1,651.5
Fish Meal ..............----- ......... ----........----- ------- .... ... 183.5 .....
Alfalfa meal .......................- ............. .............-..............- 367.0
Cottonseed m eal ................ .... ............... .. ............ ...-........ 185.5

WEIGHTS AND GAINS

Weight beginning test, Oct. 3, 1925....-..................
Weight at close of test, Nov. 17, 1925...........................
Gain in weight in 46 days ..........................---
Average daily gain ..............................-.
Average daily gain per 1,000 pounds live weight........
Pounds of corn to make 100 pounds of gain................
Pounds of fish meal to make 100 pounds gain..........
Pounds of alfalfa meal to make 100 pounds gain.......
Pounds cottonseed meal to make 100 pounds gain....

Lot I Lot II
Pounds Pounds
1,153.3 1,136.6
1,546.6 1,588.3
393.3 451.7
1.22 1.4
7.41 8.63
422.0 365.6
46.65
...- 81.0
41.0

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28R Florida Agricultural Experiment Station

TABLE IV.-RESULTS OF SECOND EXPERIMENT. (TEN HOGS IN EACH LOT.)
FEEDS CONSUMED Lot I Lot II
Pounds Pounds
Shelled corn ------------------ -------------... 2,799.0 2,799.0
Fish meal .------.....--------------------. ----311.0
Alfalfa meal .................------------------------------ ------ ..622.0
Cottonseed meal ..------ -. ---------............ .------- ---- -- 311.0

WEIGHTS AND GAINS Lot I Lot II
Pounds Pounds
Weight beginning test, Dec. 8, 1925-........--........----. 1,286.6 1,313.3
Weight at close of test, Jan. 28, 1926.......................... 1,960.0 2,080.0
Gain in weight in 51 days.. ...................... ......... 673.4 766.7
Average daily gain .......................................................... 1.32 1.5
Average daily gain per 1,000 pounds live weight...... 10.26 11.42
Pounds of corn to make 100 pounds gain.......------... 415.6 365.0
Pounds fish meal to make 100 pounds ........................ 46.1 ...
Pounds alfalfa meal to make 100 pounds gain........... 81.1
Pounds cottonseed meal to make 100 pounds gain .... --- 40.5

TABLE V.-RESULTS OF THIRD EXPERIMENT. (SEVEN PIGS IN EACH LOT.)
FEEDS CONSUMED Lot I I Lot II
Pounds Pounds
Shelled corn .......................................... ... .......1,777.5 1,777.5
Fish m eal ......................................................................... 197.5 .....
Alfalfa meal ................... ................ ........----. 395.0
Cottonseed meal ..-----................................- --------- -- ------ 197.5

WEIGHTS AND GAINS Lot I Lot II
Pounds Pounds
Weight at beginning of test, March 10, 1926................ 808.3 826.6
Weight at close.of test, May 4, 1926.............................. 1,251.6 1,285.0
Gain in weight in 55 days ..--......................... ............... 443.3 458.4
Average daily gain .----------....................................... 1.15 1.19
Average daily gain per 1,000 pounds live weight........ 9.96 10.08
Pounds of corn to make 100 pounds gain-.......--.... 401.00 387.76
Pounds of fish meal to make 100 pounds gain.............. 44.55 .-
Pounds of alfalfa meal to make 100 pounds gain........ -.....--.. 86.16
Pounds of cottonseed meal to make 100 pounds gain.... ............ 43.08

In comparing the results of the feeding experiments it will be
seen that when shelled corn and fish meal were fed it required
less grain to make 100 pounds of gain than when cottonseed meal
and alfalfa meal were fed with shelled corn. On the other hand,
when we take into consideration the average daily gains it will
be seen that shelled corn, cottonseed meal, and alfalfa meal pro-
duced a slightly better daily gain than did the shelled corn and
fish meal ration.
Both rations produced satisfactory daily gains. In all cases
the daily gain was more than one pound per day.

Annual Report, 1926

REPORT OF CHEMIST
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Chemistry for the fiscal year ending June 30, 1926.
Very truly yours,
R. W. RUPRECHT,
Chemist.

The work of the Department has been along the same general
lines as in previous years. The staff has been strengthened by
the addition of two chemists. R. M. Barnette, Ph. D., Rutgers,
started work on August 1, devoting his time to soil chemical
studies. On September 1, E. W. Cowan, M. A., Uni. of Missouri,
began his duties as Assistant Chemist, dividing his time between
looking after field experiments and analytical work in the labora-
tory in connection with field experiments.
In addition to work on our own problems, the Chemistry De-
partment is actively cooperating with the following departments
of the Station in studying chemical phases of their problems:
Home Economics, Veterinary, Animal Industry, Agronomy and
Horticultural departments.

DIEBACK OF CITRUS
In general the work on this project has been continued as out-
lined in previous annual reports. Laboratory studies with cop-
per sulfate on soils have been continued. Reaction studies of
soils have shown no correlation between the soil reaction and the
occurrence of dieback. Pot experiments to study the effect of
disturbing the carbohydrate-nitrogen ratio in the plants and
its relation to dieback were begun. The dieback grove at Lake
Alfred made a good growth and produced a fair crop of fruit.
Slight evidence of dieback appeared on a few grapefruit trees on
Plot 3 which receives ammonia from three sources, so that its
appearance cannot be laid to any one source of ammonia.
Drainage waters were collected from the soil tanks on six
dates. As none of the trees were growing satisfactorily and in
order to determine whether or not any of these tanks had rusted
thru, the trees and soil were removed during the latter part of
June. Samples of soil were taken from each tank and will be ana-
lyzed. In digging out the soil it was noted that the soil receiving
its ammonia as nitrate of soda was more compact than any of the

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others. All of the tanks were found to be in good condition and
will be refilled with new soil and used for further experiments.
The last five years' results are now being tabulated for publi-
cation.
NUTRITION STUDIES
Two new fertilizer experiments were added to those already
under way and one was discontinued. A new citrus experiment
on muck soil in the Everglades on the property of Wacico Groves
at Davie was started in February. In this experiment a study
of the effect of single fertilizer elements as well as complete
fertilizers on the growth and production of citrus trees is being
made. The extreme cold in February killed approximately 75
percent of the trees. These were replaced in May.
The second new experiment was with tomatoes in the Braden-
ton district. This experiment was similar to the experiments
conducted on the East Coast in cooperation with the U. S. D. A.,
Bureau of Plant Industry. The season was very unfavorable for
tomatoes. Heavy rains just before setting the plants and shortly
after the second application of fertilizers made it necessary to
apply a third application so that a total of 3,000 pounds were ap-
plied instead of 2,000 as was originally planned. The heavy
rains caused so much damage that it is impossible to correlate
the yields with the fertilizer treatment. It is planned to repeat
these experiments next season.
Two fertilizer experiments with tomatoes were conducted in
Dade County in cooperation with the Bureau of Plant Industry,
U. S. D. A., similar to those conducted in the previous year. The
most outstanding differences found were with the use of manga-
nese. The manganese plots in both experiments made a better
growth of vine and gave a higher yield. It is planned to con-
tinue the studies with manganese next season.
The citrus experiments at Lake Alfred comparing various
sources of phosphoric acid were discontinued due to the sale of
the grove. These experiments have been under way for 8 years
and will be written up and published in bulletin form.
The potash experiment at Lake Alfred comparing high vs.
low potash fertilization has been continued. A fair crop of fruit
was harvested and samples were taken of both oranges and
grapefruit for analysis. As yet no external difference, or dif-
ference in taste or eating quality of the fruit has been found.
Chemical analysis seems to indicate that the high potash plots

Annual Report, 1926

take up more potash but have a slightly lower sugar content than
the low potash plots.
The two experiments comparing various sources of potash con-
ducted at Lake Alfred and Vero Beach were continued. The
young grove at Lake Alfred has made a normal growth. The
grove at Vero Beach bore a fair crop of fruit and samples were
taken of tangerines, Pineapple and Valencia oranges and grape-
fruit. The analyses do not as yet show any marked differences
due to the forms of potash used. The eating quality also as yet
shows no difference. The non-acid phosphate plot was discon-
tinued due to the fact that the non-acid phosphate was unob-
tainable.
The fertilizer experiments with satsuma oranges at Round
Lake and Panama City were continued. A light crop of fruit
was gathered from the plots at Round Lake. Due to the fact
that many of the trees were replants the yield as yet is not a
fair index of the fertilizer treatment.
The pecan experiments were continued as outlined in previous
annual reports. A crop of nuts was harvested from all of the
experiments and samples taken. These are being analyzed to
determine whether fertilizer treatment affected their compo-
sition. A report of the pecan experiment conducted in cooper-
ation with the U. S. D. A. was made before the meeting of the
Georgia-Florida Pecan Association, by Dr. J. J. Skinner of the
Bureau of Plant Industry. The main conclusions to date were
as follows:
1. On both the Bladen fine sandy loam and the Norfolk fine
sand fertilizers have had an influence in producing a more rapid
tree growth and increased nut production. 2. Ammonia and
potash seem to have more influence than phosphate in both tree
growth and nut production on these soils. 3. Potash apparently
has more influence on pecans on these soils than on the heavier
soils on which pecans are grown in central and southern Georgia.
Various new forms of fertilizer materials were tried out in
the small concrete tanks. The materials tried were as follows:
Tung-oil cake, the cake left after the oil had been extracted. This
analyzes about 3.5 per cent ammonia; Urea and leunasaltpeter,
two of the synthetic ammonia compounds now being imported
from Germany, were used with acid phosphate and sulfate of
potash in such proportions as to give a fertilizer application
equivalent to 1,000 pounds per acre of a 5 percent ammonia,

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7 percent available phosphoric acid and 5 percent potash fer-
tilizer. All of the materials produced a good crop of beans.
MINERAL CONTENT OF GRASSES AND FORAGE CROPS
Eighty-one additional grasses and forage crops were analyzed
during the year. About half of these were obtained from the
Everglades Station thru the cooperation of the Agronomist.
While there is a difference in the mineral content of grasses and
forage crops grown in the Everglades and at Gainesville, the
difference is not the same in all cases. In some grasses the
potash content is higher in that grown at Gainesville while in
other grasses the reverse is true, or there is no difference in the
potash content, but there is a difference in the calcium content.
Further analyses will be made to determine whether the differ-
ences noted are seasonal or permanent.

MISCELLANEOUS
In the soft pork investigation only one series of fats was
analyzed.
The fertilizer experiment with shade tobacco at Quincy was
continued. Due to severe nematode injury on several areas in
the old land the yield of tobacco was materially cut down and no
definite effects of the various fertilizer treatments could be
obtained.
The only fertilizer experiment conducted at the Everglades
Station by this department was with Irish potatoes. This ex-
periment was similar to the one conducted the previous year.
Spaulding Rose was planted and gave a good yield but did not
show any consistent differences that could be attributed to the
fertilizer treatment. The department cooperated with the
Agronomist in planning a long time series of experiments at the
Everglades Station. (See page 122.)

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Annual Report, 1926

REPORT OF COTTON INVESTIGATIONS
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Cotton Investigations for the fiscal year ending June 30, 1926.
A. F. CAMP,
Plant Physiologist, in charge.

COTTON PATHOLOGY AND PHYSIOLOGY
Work was continued on seed treatment to control seedling dis-
eases, especially anthracnose and angular leaf spot. A large
number of copper compounds in dust form and with low water
solubility were tried but these seemed to be less successful than
some of the commercial mercury compounds formerly tested.
This work will be continued during the coming winter under
controlled conditions in the greenhouse, since the field experi-
ments have been unsatisfactory, due to the variety of parasites
attacking the plants and the impossibility of determining the
exact cause of the death of the plant. A considerable number
of compounds are available which have not burned the cotton
seedlings and which should be more or less toxic to the disease
producing organisms.

DELINTING TEST
During the season of 1924 sulphuric acid delinting of cotton
seed gave in all cases better stands and better yields than did
undelinted seed, the increase in yield amounting, in many cases,
to 20-25 percent. Laboratory tests indicated, however, that,
aside from disease control, delinting with sulphuric acid had
very little effect, even upon germination. With this in mind an
experiment was planned to determine what effect, if any, delint-
ing would have upon non-infected seed. For this work a sample
of Council Toole seed, which was as nearly free from anthracnose
and angular leaf spot as could be found, was used. Half of this
sample was delinted thoroly with sulphuric acid. Sixty samples
of 500 seeds each were then counted out from the delinted seed
and the same from the undelinted. Only good seed were used, all
light or immature seed being discarded.
A block of 120 rows 65 feet long was used and each row was
planted with one of the 500-seed samples, delinted and undelinted
seed being used on alternate rows. All the planting was done

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Florida Agricultural Experiment Station

by hand and in the same way since no planter was available
that would use both types of seed satisfactorily. The soil was
very dry at planting time and continued so for some time.
When the plants started to appear the number of plants in
each row was recorded daily. In order to eliminate personal
errors in counting, no worker was allowed to count all delinted
or all undelinted rows, but rotated so as to count some of each.
The results of this counting, which continued until April 30, are
shown graphically in Fig. 1. The average number of plants per
row which had appeared each day is indicated by a circle for
the delinted cotton seed and a triangle for the undelinted. It
will be noted that from about April 16 to 20 there was very little
increase in the number of plants which had appeared and the
curves flatten out but later rise rapidly again. This is explained
by the fact that the soil was very dry prior to this time and many
of the seeds did not germinate until after the rains of April 17
and 18; 0.48 of an inch fell on the 17th and 0.24 of an inch on
the 18th.
TABLE VI.-DELINTING TEST
PLANTS PER ROW AFTER THINNING
Plants I Rows Listed According to Number of Plants in Each
per I On May 4 On May 21
Row Delinted Undelinted I Delinted Undelinted

58 .... ....... 1
59 .... .... 1 2
60 .... ... 3 6
61 .... .... 3 10
62 1 1 8 9
63 1 1 8 8
64 3 5 18 9
65 53 53 19 14
66 2..
67 ...
68
69 ... .. .... 1*

Average No. plants per row ........................... 63.5 62.7

(*Probably due to late germination.)

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Annual Report, 1926 35R

On May 2 the rows were thinned by hand to one plant per foot,
using a steel tape for measuring and making every effort to get
the rows uniform. On May 4 the number of plants per row
was recorded. Subsequently some of the plants were killed by
disease, rodents, etc., but the number of plants per row fell off
very slightly. On May 21 they were again counted and the re-
sults of these counts are given in Table VI. Subsequently no
more dead plants were noted.

i

7, -

Fig. 2.-Germination of cotton seed from delinted and undelinted plant-
ings. Plants from delinted seed-0. Plants from undelint3d seed-A.
On May 24 careful measurements were made of the height
of 300 plants from delinted and 300 from undelinted seed. The
300 plants were distributed over 12 rows in each case and these
rows started with the first delinted and the first undelinted row
and took in every 5th row of each thereafter. Twenty-five plants
were measured on a row, taking the plants in order in the cen-
tral part of the row. The measurements were made from the
first node cotyledonss) to the terminal bud. The results are
as follows: An average height of 14.45 cm. for the delinted rows
and 14.29 cm. for the undelinted rows.* Fig 2 is a graph show-
*The probable error of the mean for these figures is as follows:
Delinted 14.45 + 0.16, undelinted 14.29 + 0.155, difference 0.16 + 0.223.

Florida Agricultural Experiment Station

ing the distribution of plant heights in 2 cm. classes with direct
comparison of heights in the delinted and undelinted rows.
The pickings were made and weighed separately for each row
and the figures for the first picking and for the total yield of
seed cotton calculated as pounds per acre are as follows:
First Picking Total Crop
Undelinted seed ..........................-- 445 2020
Delinted seed .....................-....---...477 1985*

DISCUSSION OF DELINTING TEST
It will be noted from the curve for germination (Fig. 3) that
the delinted seed germinated a little more rapidly than the un-
delinted seed. On the average this advantage probably did not
exceed one day. The number of plants produced from both the
delinted and undelinted seed was in the end practically identical.
Theoretically, at least, the extremely dry soil should have fa-
vored the delinted seed, resulting in the maximum difference be-
tween the two types of seed, altho this may not be strictly true.

4; ,--~-

dI-

r~_ i-

i I ]
- - i- - L'- -

4I
h ,.
I* L

i ~ ~ -
F--h-- I-

Delinted - - Undelinted
Fig. 3.-Comparison of heights of cotton plants from delinted
and undelinted seed.

*The yield data given above with the differences and the probable error
of the mean are as follows:

First Picking
Undelinted ......................................445.2+21.3
Delinted ............................. ..... 477.5+26.9
Difference ....................................... 32.3+34.31

Total
2020.1+36.8
1985.4+40.3
35.7+54.57

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i

Annual Report, 1926

The measurements of the plants, made on May 24, indicate
very decisively that by that time any advantage in growth that
the delinted seed may have had due to their earlier germination
had completely disappeared. The large number of plants used
and their distribution thruout the plot made the figures very
accurate.
In such an experiment as this the yield is of course the decid-
ing result but it will be noted that there is only a very slight
and insignificant difference in total yield in favor of the unde-
linted seed, so slight in fact as to be entirely insignificant. For
the first picking, which should be the significant indication .of
earliness, there is a difference in favor of the delinted seed, but
here again the difference is so small as to be insignificant.
The logical conclusion of the above experiment must be that,
while apparently the delinted seed may germinate a little more
rapidly than the undelinted, this advantage is soon lost, and that
no advantage is to be gained in yield providing the planting
methods are identical and the seed disease-free.
The above results do not, however, detract from the value of
delinting. An analysis of previous experiments and those of
1925 indicate that at least two factors are very important in pro-
ducing the increased yields from delinted seed which are usually
obtained. The first is disease control, which results in better
stands and in better plants where the seed are originally infected.
During 1924 a 25 per cent increase in stand from the delinted
seed was almost always obtained and the blocks planted with
delinted seed could easily be identified on account of the better
appearance of the plants due to a lack of anthracnose and angular
leaf spot lesions.
The second factor has to do with the method of planting.
Undelinted seeds are almost universally planted with the Gantt
type of planter in this section. This planter uses a board for cov-
ering the furrows and the tendency is to draw in dry soil from
the sides of the furrow to cover the seed. The delinted seed are
planted with a Cole or Avery planter which makes use of a shoe
and a wheel packer. This type plants in a narrow groove cut by
the shoe which closes up laterally, keeping the seed in contact
with the deeper damp soil which is then packed with a heavy
wheel, the dry surface soil being-kept away from the seed. This
effect is very pronounced when the weather is dry, and the sur-
face soil loose and dry. During the spring of 1925, in some of
the drier parts of the general field, seed planted with the Gantt

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Florida Agricultural Experiment Station

type of planter did not come up for two weeks, whereas seed
planted with the Cole type were up in three or four days.
Planters of the shoe type which will plant undelinted cotton may
be obtained at a higher cost than the ordinary type and with
them the advantage mentioned above for delinted seed would be
almost entirely lost, and the value of the method would depend
largely on disease control.
OTHER ACTIVITIES
The large soil tank was moved to the new greenhouse and
equipped with a new refrigerating system. A study was made of
the behavior of the tank itself and of the germination and growth
of cotton and it is intended to publish this shortly. Further
studies have been made with anthracnose and rhizoctonia and
as soon as they are confirmed sufficiently, results will be pub-
lished. Another tank containing 35 pots was installed and will
be used to determine the relation of soil moisture to seedling
infection. This tank will also be used for controlling conditions
while the effect of various seed treatments is determined.
While most cotton diseases did considerably less damage than
they did in 1924, rust was found much more prevalent and much
more widespread than during the previous two years. This
seemed to be particularly true in those sections of western Flor-
ida where the soil is extremely light and where very little or-
ganic matter is present in the soil. The damage due to this trou-
ble was very extensive and was especially evident in the quality
of staple obtained from the bolls set later in the season. Work
on rust was inaugurated this year on the fertilizer plots and an
extensive study is in progress concerning the carbohydrate-nitro-
gen relation in the cotton plants grown with various fertilizers.
Special attention will be given to the effect of applications of
potash on the metabolism of the cotton plants in the hope that we
may arrive at a reason for the known effect of potash on rusted
plants. If rust develops in the experimental field this year a
careful study of the carbohydrate-nitrogen relation of the af-
fected plants will be made and compared with the results of
similar plants. treated with potash.
The fertilizer test for the 1925 season was carried out suc-
cessfully and is being repeated again on the same plots. The
plots for this season were severely injured by a wind storm and
this year's results will probably be incomplete.

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Annual Report, 1926

COTTON BREEDING AND VARIETY TESTING
The variety tests were continued during the season of 1925
and are being repeated during this season. At the completion
of this season's work it is intended to publish the results of va-
riety tests for the years 1923, '24, '25, and '26 and of spacing
tests for the years 1924 and '25 in bulletin form. Lightning
Express No. 3 and Lightning Express No. 4 continue to be the
most outstanding among wilt-susceptible varieties and Cook 307-6
among wilt-resistant varieties. The results of the spacing test
compared closely with those obtained in 1924 and indicate that
a spacing of 18 inches with two plants per hill or 12 inches
with one plant per hill gives best results for average Florida
soils.
Individual plant selection work was begun during the sum-
mer of 1925. Selections were made among the most promising
varieties, selecting productive plants showing early maturity,
freedom from disease, open branching, small leaves and medium
size bolls which open rapidly and well. The following gives the
most promising varieties as indicated by previous variety tests,
the number of plant selections made from each and the number
chosen after laboratory study for planting in the field in 1926.
Plant Selections Number of Plant
Variety Made Selections Planted, 1926
Lightning Express No. 3.......... 98 63
Lightning Express No. 4.......... 208 112
Carolina Foster .......................... 50 31
Cook 307-6 ......-............-................ 80 17
Council Toole ........-- ....--......-...... 120 38
Included in the above are 33 and 23 selections taken from plant
rows of Lightning Express No. 3 and Council Toole respectively.
These selections were planted with a check row of the parent va-
riety on one side of each plant row. Seed from several of the
most promising plant rows of the two last mentioned varieties
have been placed in a strain test in 1926. These are planted in
duplicate test plots of two 300-foot rows per plot with a single
check row of the parent variety planted on both sides of each
strain.
During the summer of 1925 13 hybrid families of Lightning
Express No. 3 by Council Toole and 27 families of Lightning Ex-
press No. 4 by Council Toole were planted. A number of pro-
ductive plants in each hybrid row were harvested and ginned
separately. As a result of a laboratory study of the fiber, 21
plants of the former cross and 77 plants of the latter cross were

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Florida Agricultural Experiment Station

selected for testing in the field in the summer of 1926. These
selections were placed in plant rows with a row of Lightning
Express No. 4 as a check on one side of each plant row. A
number of the progenies resulting from selections in the hybrid
strains and in standard varieties look very promising at the
present.
BOLL WEEVIL INVESTIGATIONS
Field tests conducted by G. D. Smith at Madison during the
summer were almost entirely negative, due to the natural con-
trol of the weevils by the hot dry weather. Weevils had been re-
leased in the plots in the spring so as to insure a high and uni-
form infestation, but the weather was so severe as to prevent
even this method from being effective.
Following Mr. Smith's resignation in the fall, E. F. Grossman
took up the work on the boll weevil. Under his direction the
field test work will be continued at Gainesville. Sixty field plots
of 1/8 acre each with corn barriers are being used to study the
cost and effectiveness of the following methods of procedure as
compared with dusting with straight calcium arsenate.
1. The Florida Method.
2. The Florida Method with an additional mopping after
stripping.
3. Mopping thruout season with "syrup mixtures".
4. Mopping with "syrup mixtures" until heavy bloom and
then dusting.
5. Dusting thruout season with calcium arsenate mixed
with an equal part of hydrated lime.
Due to the call for information concerning "syrup mixtures"
a study was made of a large number of mixtures containing
varying proportions of calcium arsenate, water, and syrup to de-
termine their mechanical efficiency and relative cost. A mixture
of 1 pound of calcium arsenate, one gallon of water and 1 gallon
of syrup (ordinarily designated as a 1:1:1 mixture) was found
to be the most effective as far as resistance to rain, drying, and
surface caking, as well as being cheaper than the more concen-
trated mixtures (3:1:1, 2:1:2, etc.) commonly recommended.
A 1:2:1 (1 pound calcium arsenate, 2 gallons of water, and a
gallon of syrup) mixture was also found to be very effective.
Also it was found that the supernatant liquid obtained when
these mixtures settled did not contain sufficient arsenic to be

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Annual Report, 1926

toxic to the weevil. This emphasizes clearly the need for stir-
ring these mixtures while using.
Laboratory tests with weevils upheld the contention that black-
strap was much inferior to higher grade syrups for making
syrup mixtures. In these experiments the weevils would actually
refuse blackstrap and in most cases feed immediately upon
higher grade syrups if offered. When starved the weevils would
feed on the blackstrap but this condition would not occur in
the field. Cage and field tests appear to substantiate the labora-
tory results indicating that the use of blackstrap in these mix-
tures is probably false economy.
Work on hibernation is being continued with special reference
to the effect of various environmental factors under controlled
conditions. During the spring of 1926 a comparison of natural
emergence with cage emergence previously obtained was car-
ried out by catching the weevils on about 2,500 plants in a field
that was in cotton during 1925, but was being cover-cropped in
1926. Up to June 30, 642 weevils had been caught, only 16 per-
cent of which were caught prior to June 5. This will probably
be followed up next year and the results correlated with weather
conditions.

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Florida Agricultural Experiment Station

REPORT OF THE ENTOMOLOGIST
Wilmon Newell, Director:
SIR: I submit the following report of the Department of
Entomology for the fiscal year ending June 30, 1926.
Respectfully,
J. R. WATSON,
Entomologist.
THE NEW CITRUS APHID
(Aphis spiraecola Patch)
This aphid did much less damage to the early spring growth
than during the two preceding seasons. This was due to the
small number that were able to develop during the winter. The
winter was characterized by rather steady cold that kept the
young citrus trees thoroly dormant and there was, during De-
cember and January, very little new growth on which the
aphids could feed. Previous work had indicated that the winter
season was the weak point in the life history of the insect and
growers were strongly urged to make an especial effort to rid
their groves of the pest during the winter, and to force the
growth as early in the spring as seemed relatively safe from
the standpoint of frost hazard. The quite general adoption of
these recommendations was probably a factor in reducing the
amount of injury. As a result of the past year's work we have
more confidence in our ability to handle this very dangerous pest.
Study of the amount of fruit on trees and parts of trees se-
verely injured by aphids during the spring of 1925 shows con-
clusively that severe injury to the spring growth seriously cuts
down the amount of fruit that the injured tree or limb will set
the following year. Limbs on which foliage was badly curled
and dwarfed during the spring of 1925 are generally carrying
very little fruit as compared with limbs on which there was lit-
tle injury. This rule also applies to whole trees, groves, and
communities. The portions of the state worst damaged by
aphids last year have a comparatively light crop of fruit.
In cooperation with the State Plant Board studies on the life
histories, habits, seasonal abundance, food preferences, parasites,
and general efficiency of the chief predators of this aphid have
been continued. As a result of these studies we have very com-
plete detailed information on the chief ladybeetle and syrphus
flies of the South. It has been found that the chief checks on

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Annual Report, 1926

the multiplication of these predators are parasites, especially
fungi and bacteria that kill the larvae. Some of them are
markedly seasonal in their development. For instance, all but
one species of syrphus flies completely disappear during the
summer.
SIt has been found that heavy, dashing rains are very destruc-
tive to the aphids. Sometimes all but those in the tightly curled
leaves were destroyed.
Large numbers of the Chinese Ladybeetle (Leis sp.) imported
from California by the Experiment Station have been reared
and liberated in groves. In one grove where they were liberated
last season they have been recovered this year, showing that they
can go thru the winter out of doors. They hibernate during most
of the winter. This habit will be of great benefit in enabling
them to bridge over the winter season when the aphids are
scarce.
In spite of the scarcity of aphids on which to work much, ex-
perimentation with means of control was carried on. A "travel-
ling hood" was fitted over the power duster to permit dusting to
be done in the wind. Trials of this hood demonstrated that it is
entirely practical for trees up to a height of 20 feet and will
permit trees to be dusted in a wind considerably stronger than
the average during the spring aphid season.
A large number of insecticides were tried. One of the most
promising is finely ground tobacco, "snuff". This, when applied
to wet foliage, sticks well and not only kills the aphids already
on the foliage, but acts as a repellant for a few days. This ma-
terial is very much cheaper than nicotine sulphate-lime dusts.
Derrisol was tried out in comparison with nicotine sulphate.
Its action is much slower, but it seems to have a repellant effect
for a day or two. It may not penetrate the curled leaves quite as
well as nicotine sulphate. Other promising sprays that seem
perfectly safe on tender foliage are certain emulsions of pine oil.
Whether or not they can be placed on the market at a sufficiently
low price to be practical has not been determined.

FUMIGATION
In cooperation with a commercial insecticide company, ex-
tensive tests have been conducted in the fumigation of citrus
trees with calcium cyanide dust. This work has been carried on
from September to March, and again in May and June. It ap-
pears that by this method fumigation can be conducted at any

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Florida Agricultural Experiment Station

time of the year when spraying with oil emulsions is practicable,
in sunlight as well as at night, and under any ordinary weather
conditions except when the trees are wet.
The kill of whitefly larvae and purple scale has been about 95
percent. Except for an occasional tree where something appar-
ently went wrong (in many cases the instrument used for meas-
uring the dust did not at first work well) the only purple scales
that escape are those under some protection such as other scales,
or those in a colony of the woolly whitefly. Even a spider web
appears to give some protection to scales under it. In most
cases of this kind there were only a few eggs that escaped.
The kill of Florida red scale has been especially satisfactory,
96 per cent. This scale is difficult to kill with an oil emulsion
spray because of its thick covering. In the fumigation experi-
ments the kill of this scale was found to be even higher than
that of the purple scale, due to the fact that it does not have as
strong a tendency to crawl under some protection.
Experience of the past year indicates that fumigation will con-
trol rust mites for two or three months. These observations
were made in groves in which only a small part of the trees were
fumigated, so that the opportunity for reinfestation was great.
Doubtless if the whole grove were fumigated reinfestation would
be much slower.
NEMATODE CONTROL
Further tests of calcium cyanide as a soil fumigant for control
of rootknot were carried on. It seems to make little difference
whether the cyanide is in the form of a dust, flakes or granules.
The granules and flakes are more easily handled. It would seem
that the fertilizer value of calcium cyanide is less than that of the
double treatment of sodium cyanide and ammonium sulfate.
The results of the application of calcium cyanide to peach
trees, of which mention was made in the last annual report, were
not as striking. A severe drought interfered with the results,
since the situation of the tree as regards a supply of soil moisture
was more important in determining growth than the cyanide.
THRIPS
A study of the breeding places of the Florida flower thrips
(Frankliniella tritici bispinosa Morgan) shows that these insects
are not as closely confined to flowers as heretofore supposed.
Altho the adults are found mostly in flowers, where most of the

44R

Annual Report, 1926

feeding is done, the larvae were found to be common on almost
any tender succulent growth. The young and tender shoots of
the cherry laurel were found to be a favored breeding ground.

THE VELVET BEAN CATERPILLAR
(Anticarsia gemmatilis)
A new development in the study of this insect was heavy at-
tacks on soybeans. They were almost completely defoliated.

THE BEAN LEAF-HOPPER
(Empoasca fabae)
During the fall of 1925 in cooperation with the Extension
Division the Assistant Entomologist carried on field experiments
for the control of the green leaf-hopper common on beans. These
experiments in the main consisted of spraying or dusting the
beans with the use of a hood of some sort which could be moved
along the row. A hood for spraying was' first employed by A. H.
Beyer and is described by him in Bulletin 164 of the Florida
Agricultural Experiment Station. The contrivances used con-
sisted of light frameworks of wood or wire hoops covered with
heavy muslin or light canvas and mounted on runners so that
they could be drawn along the row. A flap with a slit in the
middle extended part way down the front and another hung
down at the rear. A slit was made in one side of the cover for
the insertion of the spray or dust nozzle. These hoods were de-
signed for use with hand dusters or sprayers but hoods of similar
structure can be rigged up for use with power outfits. In fact
a cover was arranged over a power sprayer and this worked
quite satisfactorily.
These contrivances tend to keep the adult leaf-hoppers from
flying away and confine them with the spray or dust for a few
seconds so that a great many more of them are killed than when
the spray or dust is applied in the open.
When nicotine sulphate at the rate of 1 part to 800 parts of
water is applied under such a hood very good control of the leaf-
hoppers can be obtained.
Nicotine dusts of varying strengths were used. It was found
that a 3 percent dust caused 80 to 90 percent of the leaf-hoppers
to fall to the ground but after a few minutes a great many of
them were noticed to revive and crawl back to the beans. With
a 5 percent dust practically all the leaf-hoppers, both nymphs

45R

Florida Agricultural Experiment Station

and adults, fell to the ground and very few of them were ob-
served to revive and go back to the beans.

LIFE HISTORY NOTES ON THE CITRUS APHID
(Aphis spiraecola Patch) 1925-1926
The life history work on the citrus aphid which was conducted
by Assistant Entomologist A. N. Tissot on the Station grounds
at Gainesville was carried on entirely out of doors. In October,
1925, an attempt was made to rear the aphids in the insectary
but it was difficult to get sufficient tender growth on the young
potted citrus seedlings which were available to support more
than a very few aphids. On account of this lack of food in the
insectary the. experiments were transferred to some young
Cleopatra stock, and there they have been conducted to the
present time. In addition to providing a better food supply, rear-
ing the aphids in the open has the added advantage that they are
more nearly under natural conditions and are not subject to the
protection which the insectary would afford them.
In order to prevent the aphids under observation from wan-
dering and getting lost, and also to prevent other aphids from
mingling with them, cloth bags were placed over the shoots upon
which they were feeding. These bags were about five by seven
inches and were slipped over the end of the shoot and tied
about the twig with twine.
That records might be obtained which would give as nearly
true averages as possible a great many aphids were reared. The
number under observation was limited at certain times by the
amount of tender growth on the young trees. At other times
when suitable growth was plentiful, the amount of time neces-
sary to check up and record the development of the aphids was
the limiting factor.
In addition to keeping records of the development of the
aphids, note was made of their general behavior and the effect
upon them of weather conditions, natural enemies, etc.
The most important factors in determining both the rate of
development and the rate of reproduction of the aphids are
the condition of the growth upon which they are feeding and
weather conditions, especially temperature. When the aphids
are feeding on tender succulent growth, they develop more
rapidly, attain a larger size and give birth to a larger number of
young than when they are on more mature growth. That tem-

46R

Annual Report, 1926

perature is an important factor is evident by comparing the rate
of development and rate of reproduction as indicated in Tables
VII and VIII, for March and for May.

TABLE VII.-RATE OF DEVELOPMENT OF APHIS SPIRAECOLA, 1925-1926

~4-44U

When Born

z
i~ai-

Co
a

mP.

November ............... 15 15 6

March 1-15 .............. 32 17 10

March 16-31 ............ 143 13 7

April 1-15 .............. 129 11 5

April 16-30 ............ 72 13 7

May 1-15 .............. 42 9 5

May 16-31 .............. 17 9 6

June 1-15 ............... 10 9 6

June 16-30................ 16 9 5

TABLE VIII.-RATE OF REPRODUCTION OF

Z'0'
4 (V
01
p4-4 0
EO U Q
&^P;

APHIS

$-
o
gl

>
-;L

November .. 9 11 51 2.7 34 12.2 32 22.1

March ....... 9 11 89 3.9 62.9 15.7 50 34.2

April ............ 12 9 128 4.1 70.9 17.3 37 29.7

May 1-5 .... 21 11 82 4.1+ 55.8 13.5 32 22.6

May 16-31 .. 22 11 70 3.1 26.7 8.7 26 17.2

June ........... 6 7 71 3.1 49.1 15.6 27 23.6

4a
n-^
U2n
i a S
U5 O
;4 0

Month

Table VII shows the rate of development of the aphids during
different months of the year. The development period is con-
sidered as the time elapsing between the birth of a nymph and

"H 4
0 'o

z

47R

72.4 49.8 61.1

66.6 43.1 54.8

73.0 52.5 62.7

79.0 56.2 67.6

79.9 54.4 67.1

84.9 61.5 73.2

88.2 62.2 75.2

90.2 65.6 77.9

88.6 70.0 79.3

SPIRAECOLA, 1925-1926

t 44 m 1 m
< 3 g
--,-,

Florida Agricultural Experiment Station

the time when it in turn gives birth to young. The develop-
ment periods thus represent average generations at different
times of the year.
Table VIII is a record of the number of young produced by
all the females of which complete records are available.
A temperature of 25 degrees F. was found to kill some of the
aphids outright and a great many more were destroyed indirectly
by the freezing of the tender growth upon which they were feed-
ing. These latter wandered about for a time and ultimately
starved to death.
Observations of the past year seem to indicate that the most
favorable temperature conditions for the development of the
aphids are average daily maximum temperatures of 80 to 85 de-
grees F., and average daily minimum temperatures of 60 degrees
F. or above. When the maximum temperature is above 90 de-
grees for a few days there seems to be a slowing up in the rate
of growth of the aphids and also a decrease in the daily and total
number of nymphs produced. Likewise development seems to
be retarded when the average minimum temperature is below
50 degrees for a few days.
To the list of previously recorded food plants of the citrus
aphid should be added apple and cherry laurel (Laurocerasus
caroliniana). Early in May a few apple trees on the Station
grounds were very heavily infested with these aphids. A few
aphids were observed on cherry laurel at different times but at
no time was the infestation severe. The few which were found
were always on the very tender growth.

PECAN INSECTS
The pecan insect work in charge of H. E. Bartley, has been the
continuation of the biological studies of the economic insects and
their parasites, also the experiments on control. Special atten-
tion has been given to the spread of destructive insects and the
seeking of controls for them. The insects receiving the most
attention have been the, leaf case-bearer, nut case-bearer and
shuck worm.
A complete file of insect infestations reported by the growers
has been kept in cooperation with the Pecan Culturist. This
method has enabled the writer to keep in touch with the needs
of the growers. Also the applications of sprays for the control
of the leaf case-bearer, cigar case-bearer, bud moth and the con-

48R

Annual Report, 1926

trol of scab have been carried on in cooperation with the Pecan
Culturist.
The experiments conducted in Mr. H. H. Simmons' orchard
in Duval County last season have been discontinued, due to the
change of ownership of the orchard. A check was made of the
insects as soon as their damage could be noted and the results
were from 60 to 90 per cent control, varying as to the kind of
sticker used and the thoroness of the application of the spray.
The spray having Kayso as sticker gave the best control.
Mr. Maynard Crane's orchard located at Mandarine in Duval
County, has been taken to carry on control experiments. This
orchard had been sprayed during the summer season of 1925 by
the owner. The control of leaf case-bearer on the lower limbs of
the trees was perfect, but the tops were heavily infested. His
spraying equipment was inadequate to reach the tops of the trees.
Sprays have been applied this year on May 21 to 24, and checked
on June 22 when the second application was made. The check
on June 22 gave about a 50 percent control.
The following are the formulae for the various plots:
44-5-50 Bordeaux and 1 lb. arsenate of lead
May 3--4-50 Bordeaux and Yz lb. arsenate of lead
2-3-50 Bordeaux and % lb. arsenate of lead
Used Kayso as sticker in each.
SJ 4-5-50 Bordeaux and 1 Ib. arsenate of lead
June 4-3-50 Bordeaux and % lb. arsenate of lead
Used Kayso as sticker.
The results of the spraying experiments in Mr. J. H. Wells'
orchard in Duval County were 90 to 95 percent control with
arsenate of lead with Kayso sticker and 80 to 90 percent when
flour was used as sticker. The result when calcium arsenate
was used as the poison in the spray gave from 65 to 85 percent
control. This low percentage may have been due to a poor grade
or the age of the calcium arsenate used.
SIn the Monticello area, in cooperation with the Pecan Cultur-
ist, a number of dusting experiments were started in May and
June to test the value of dusts in controlling the insect pests of
the pecan. If this proves successful, dusting will be far the
cheapest artificial means of control.
The case-bearers have proven far the most destructive insects
to the pecan. The nut case-bearer has proven the worst of the
three, followed closely by the leaf case-bearer. The nut case-
bearer appeared in Mr. J. H. Wells' orchard in Duval County
about the middle of June. This is the first infestation noted
outside of the Monticello section.

49R

50R Florida Agricultural Experiment Station

It is planned to carry on some intensive biological studies in
regard to the nut and leaf case-bearers and other insects that
are liable to become destructive pests. These studies include life
history studies, breeding experiments, the collection of parasitic
insects and the determination of the amount of parasitization in
regard to the percentage of control they exert. Arrangements
have been made for the carrying on of the spraying experiments
now running and the addition of other control measures as they
are needed.

Annual Report, 1926

REPORT OF ASSISTANT HORTICULTURIST
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Horticulture for the fiscal year ending June 30, 1926.
Respectfully,
HAROLD MOWRY,
Assistant Horticulturist.

Since the report of last year some work with bulbs and straw-
berries has been instituted in addition to the regular projects
dealing with grapes, berries, persimmons, pears, tung-oil, avo-
cados, and miscellaneous fruits and ornamentals.
CITRUS
In the satsuma rootstock project, which includes testing the
Owari and Wase varieties on several rootstocks, additional plant-
ings have been made in both nursery and field. The unseason-
able weather of the past winter damaged some of the small buds
in the nursery which has delayed the completion of the field
planting for at least one season. At this time the Rusk and Mor-
ton citranges, and the citrangequat appear very satisfactory
From the nursery viewpoint. All make a vigorous growth in the
nursery row and may be propagated by cuttings as well as seeds.
They are believed to be hardy thruout the whole of the state.
The smaller trees in the citrus grove, which includes several
varieties of oranges, grapefruit, and some hybrids, were, with
few exceptions, frozen to the bank during the past winter. Inas-
much as this is to be expected at intervals and plantings are now
becoming well established at the Lake Alfred branch station,
it is the intention to replace all such losses in the future with
satsumas, gradually converting the planting into a satsuma
project.
BERRIES
In cooperation with the State Plant Board, duplicate plantings
of strawberries were made at Plant City and Starke. These
plantings include the varieties listed below in addition to 16
hybrid varieties furnished thru the courtesy of Mr. Geo. M.
Darrow of the U. S. Department of Agriculture: Aroma, Big
Late, Brandywine, Bubach, Chesapeake, Cooper, Dr. Burrill, Ex-
celsior, Gandy, Glen Mary, Haverland, Horsey, Klondyke, Lady

51R

Florida Agricultural Experiment Station

Thompson, Lord Salisbury, Lupton, Mascot, Missionary, Nick
Ohmer, Norwood, Ozark, Parson's Beauty, Premier, Prince, Sam-
ple, Sen. Dunlap, The Best, and Wm. Belt.
Owing to the dry weather of last fall it was not possible to
obtain plants nor to plant in the field as soon as desired and be-
cause of this late planting conclusive results on all varieties could
not be obtained from one season's tests. Generally, however, it
would seem that none of the varieties, hybrids or crosses ex-
cepted, were superior, and few equal, to the Missionary, which is
at present considered the standard variety for Florida conditions.
Those varieties showing the most promise as to firmness, quality
and disease resistance are being propagated for further trial.
From present indications, the ultimate strawberry for Florida
will probably be a cross or hybrid type and it is the intention to
secure and thoroly test as many of such as can be obtained.
In addition to varieties in the berry (Rubus spp.) plantings
previously reported the following have been added:

S Blackberry
Bowers Rubus fraxinifolius
Eldorado Rubus glaucus
Erie Rubus niveus
Mercereau Rubus sp. SPI No. 56114
Nanticoke Rubus sp. SPI No. 58999
Rathbun Rubus sp. SPI. No. 60586
Snyder Rubus sp. SPI. No. 62322

Fig. 4.-View of portion of horticultural test grounds.

These additions make a total of 29 varieties now under obser-
vation in the plantings on the test grounds. Of the older plant-
ings, the Florida Marvel, McDonald, Dallas and an unknown va-
riety obtained from California are giving most satisfactory

52R

Annual Report, 1926

results as to vigor of growth, productiveness, and earliness of
maturity.
The Cory Thornless, Himalaya, and Logan varieties have
proven entirely unsatisfactory under local conditions, as have
also all varieties of raspberries tested, the Van Fleet excepted.
The Florida Marvel, Young, and Lucretia varieties are sus-
ceptible to infection by the "double-blossom" disease. A variety
locally termed the "White Blackberry" is also susceptible.
The Nessberry has made a fairly vigorous growth and bears a
good quality fruit in fair quantity. Unfortunately, the drupelets
tend to separate in picking which makes it unsatisfactory for
marketing purposes. The Haupt dewberry makes a vigorous
cane growth and has an exceptionally heavy bloom but sets
few or no fruits. This would seem due to faulty pollination but
as the plants are set among other varieties which are in bloom
at the same date, which should aid in cross-pollination, no definite
cause can as yet be ascribed to this non-setting of fruit. The
Lucretia and Austin, or Mays, dewberries have proven only
partially satisfactory, both in vigor of growth and amounts of
fruit produced.
PEAR
Additions to the pear plantings during the past season have
brought the total of varieties and species, including hybrids, to
43. None is as yet of fruiting age.
MISCELLANEOUS FRUITS
Seventeen varieties of apples have been planted in the miscel-
laneous fruit planting. This includes orie variety, the budwood
of which was obtained from Hawaii, grafted on the native wild
crab apple, Malus coronaria.
In addition to plantings made on the horticultural grounds, 48
of the figs grafted on a supposedly root-knot resistant Ficus sp.
have been distributed for planting in several counties in the
southern portion of the state.
Altho some of the young trees were killed back severely, none
of the avocades in the avocado test planting were killed outright,
some having only a slight leaf injury by frosts.
GRAPES
Other than the testing of some vigorous growing sorts as root-
stocks, no additions have been made to the vineyard plantings.
Observations of the variety plantings made in January, 1923 are

53R

TABLE IX.-OBSERVATIONS OF GRAPE VARIETY PLANTINGS.

Variety a ,

Albania ................. Fair Medium
America .................... Fair Light
Armalaga ................. Fair Light
Bailey* .................. Fair
Bell ......................... Dead Light
Blondin .................... Strong Medium
Brilliant ................... Poor Heavy
Captain ................Poor Light
Captivator ................. Poor Light
Carman ..................... Strong Heavy
Catawba .................... IFair Medium
Champanel ..--.........--Strong Medium
Cloeta ......................... Fair Light
Concord* ......----............ Fair
Cream* .....................Fair
Delakins* .................. Fair Medium
Delaware* ................. Poor
Dr. Collier* ............... Fair
Edna ........................... Strong Light
Ellen Scott .............. Strong Heavy
Elvicand .................... Strong Heavy
Ericson ...................... Fair Heavy
Extra .......................... Strong Heavy
Fern ............................ Fair Medium
Goethe* ......-.............--..Dead
Gold Coin ................. Fair Medium
Headlight .................. Fair Light
Herbemont* ............. Strong
Husmann ................... StrongI Heavy
Jacquez* ....................Strong
Herman Jaeger .......... Strong Heavy
Jaeger 43* ................ Fair !Medium
Ladano ........................Dead I

0
0'

Fair
Fair
Good

Good
Good
Good
Fair
Fair
Fair
Good
Fair
Fair

Good

Fair.
Good
Fair
Fair
Good
Fair

Good
Fair

Fair
Fair
Fair
Fir

4-25
4-15
4-28
4-26
4-11
5- 1
4-22
4-19
4-24
4-23
4-11
4-20
4-23
4-12
5- 3
4-18
none
4-26
5- 3
4-20
4-20
4-28
4-19
4-23
none
4-13
4- 6
4-28
4-21
4-22
4-22
4-17
4-20

7-20
6-26
7-24

7- 1
7- 6
6-15
6-26

6-25
7-14
7-14

7-14

7- 6
6-24
7-28
7- 6
7-14
7-17
6-20
6- 3

7- 6

7- 9
6-26

S1ill

100
100
100
75
66-%
0
100
0
33-1/3
33-1/3
100
100
100
66-%
66-%
66-%
50
66-%
100
100
66-%
100
66-%
100
66-%
0
100
100
100
100
100
100
100
0

9/16"
5/8 "
9/16"
7/16"
9/16"
11/16"
7/8 "
3/4 "
1/4 "
11/16"
3/8 "
1-11/16"
3/4 "
3/8 "
11/16"
3/4"
1/4 "
3/8 "
11/16"
11/16"
1- 1/2 "
13/16"
1- 1/8 "
5/8 "
----------;
3/8 "
3/8 "
5/8 "
15/16"
11/16"
1- 1/8 "
1/2 "
5/8 "

4p

<0;
C^g .i2^
<)~5l Q

1
4-8
2-6
4
4
2
4
2-5-6
2
1-4
2-4
2-4-9
4-5

1-4

7
4
3-4-6
2-4
4-5
1-5-7
4

4
4-8

1-7
1-3-9
1-2-3
4
5

I

TABLE IX.-OBSERVATIONS OF GRAPE VARIETY PLANTINGS.--(Continued)

Variety S e "0 m .

Last Rose ................ Dead 4-25 ........ 0 3/8 10' 2-5-6
Lomanto ............... Strong Medium Fair 4- 6 ........ 100 13/16" 46' 4
Longfellow .......... Weak none ........ 100 3/8 8' 2-4
Lukfata .............. Strong Medium Fair 4-11 7-14 100 1- 1/4 50' 4
Manito ............-..... Strong Heavy Fair 4-16 6- 8 75 3/4 44' 2-5
Manson* .................. Poot none ........ 66-% 1/4 3'
Marcus .................... Poor none ........ 100 3/8 14' 2-5
Marguerite ................ Strong Heavy Fair 5- 3 8- 1 100 1- 5/16" 47' 1-5
Mathilda ............ Fair Light Fair 4-21 ...... 33-% 7/16" 18' 5
Mericadel* ................ Fair 4-23 ........ 100 5/8 11' 5
Minnie ..................... Fair Heavy Good 5- 3 7-17 100 15/16" 15' 2
Muench .................... Strong Heavy Fair 5- 2 7-20 100 13/16" 32' 2-4-7
Neva ......................... Strong Heavy Fair 5- 1 7-21 100 3/4 25' 2
Niagara* ................... Poor none ........ 66-% 1/4 5' 4
Nitodel ...... ..... Fair Medium Fair 4- 8 6-22 66-% 7/8 24' 4-7
President ............ Poor Light Fair 4- 4 6- 3 66-% 3/8 12' 4
Rommel* ............ Poor 5- 5 ........ 100 5/16" 4' 4
Ronalda .................... Fair Light Fair 5- 5 7-14 66-% 1- 7/16" 23' 1-2-3-7
R. W. Munson ........... Strong Medium Fair 4-20 6-22 100 1- 1/8 22' 1-2-4-5
Sabinal* .............. Strong 4-17 7-14 100 3/4 34' 1
Salem ..............Strong Heavy Good 4-15 6-15 100 15/16" 51' 1-3-4
Valhallah ................. Strong Heavy Poor 4-21 7-23 100 3/4 33' 4
Volney ........................ Poor Light Fair 5- 5 7-14 33-1/3 5/8 19' 8
Wapanuka* ............ Fair 4-26 .... 66-% 1/4 6' 4
W. B. Munson .......... Strong Medium Fair 4-23 7-24 100 1- 5/16" 44' 4
Winchell ...................... Poor Light Fair 4-17 ........ 100 7/16" 13' 4
Wine King ..............trong Medium Fair 4-16 6-26 100 9/16" 21' 2
Zinfandel .................. Weak I_, 4-26 ....... 100 1/4 2' 4

Average maximum cane length given as above denotes extreme growth of vine both ways on trellis.
*Denotes two year vines, planted December, 1923.
**Diseases referred to above: 1, Bitter rot; 2, black rot; 3, anthracnose; 4, leaf blight; 5, downy mildew;
6, powdery mildew; 7, phylloxera-leaf inf. only; 8, chlorosis; 9, rust.

Florida Agricultural Experiment Station

given in Table IX. The varieties marked were planted in De-
cember of the same year. All have been grown on the Munson
3-wire canopy trellis and have been given like treatment as to
cultivation, spraying, and fertilization.
TUNG-OIL
Fertilizer and cultural experiments as heretofore outlined
have been continued. Two hundred pounds of seeds and some
trees were distributed to 173 farmers for trial planting.
Thru the courtesy of Dr. H. G. Gardner, who furnished the
seeds, test plantings were made of chia (Salvia hispanica) and
perilla (Perilla nankinensis), the seeds of which are the source
of oils which may be used in making paints, etc. An excellent
stand was secured from early March planting, the seeds germin-
ating one week after planting. The chia attained an average
height of 41/2 feet but did not bloom, the plants dying at about
time blooming should have started. The perilla made a vigorous
growth, attaining a height of 5 feet, blooming profusely by Sep-
tember 3. So few seeds were produced that no effort was made
to harvest them.
IMPROVEMENTS
Permanent improvements made during the past fiscal year
consist of a modern greenhouse 17x93 feet, together with heating
plant, an implement shed of sufficient size to adequately house all
farming implements, and a plant slat shed 40x60 feet.

56R

Annual Report, 1926

REPORT OF THE LIBRARIAN
Wilmon Newell, Director.
SIR: I submit the following report of the Library for the fis-
cal year ending June 30, 1926.
Respectfully,
IDA KEELING CRESAP,
Librarian.

Cataloging and indexing the material in the library have pro-
gressed satisfactorily this year. Five thousand titles have been
prepared and added to the card catalog. In addition to these,
the cards printed by the Library of Congress for the literature
of the U. S. Department of Agriculture have been received and
arranged in the catalog.
Five hundred new volumes have been received and acces-
sioned. This is nearly twice as many volumes as ever have been
added to the shelves in one year. Of this number 269 volumes
were prepared and sent to the bindery for binding. Several
thousand reports, bulletins, pamphlets and papers from the vari-
ous Experiment Stations, Departments of Agriculture, and other
agricultural institutions of this and other countries have been
received and properly filed. The library now has accessioned
5,000 bound volumes, besides several thousand unbound volumes.
The librarian also has prepared and sent to the bindery 46 vol-
umes for the various departments of the Station.
The daily routine of work is so heavy that it requires the al-
most undivided time of one person to attend to it. Student
help, totaling a little more than one month's time, was the only
assistance to the librarian, until June, 1926, when one person
was employed for regular half-time. A definite program, alone,
has made possible the progress of the work in the library for
the year.
To be of the greatest service to the research workers, a spe-
cial study of literature dealing with tropical and sub-tropical
agriculture is being made. In connection with this, and to as-
certain means of improvement in the library, two weeks were
spent, by the librarian, in the Library of the U. S. Department
of Agriculture. Considerable material has been added, includ-
ing publications of several important agricultural centres in
the tropics. Work is also being continued on the citrus col-

57R

Florida Agricultural Experiment Station

election and in connection with this considerable progress has
been made on a card catalog for same.
The addition of so many new volumes was made possible by
the increase of the fund in the original budget for the year.
Among the accessions that are particularly important and valu-
able are:
Berichte der Deutschen Botanischen Gesellschaft.
Biochemical Journal.
Chemisches Zentralblatt.
The Silva of North America.
Transactions of the Linnean Society. (London).
With the library functioning more efficiently it is assuming
greater importance to the research workers of the Station and
College of Agriculture and to the advanced students.
The library is indebted to the Misses McQuarrie, daughters of
the late C. K. McQuarrie, formerly State Agent, Agricultural
Extension Division, of this Station, for 20 volumes on agricul-
ture, belonging to the latter's library, which are greatly appre-
ciated.
Every assistance possible has been rendered the library pa-
trons and when material sought was not to be had here, it has
been secured or borrowed elsewhere for them.

58R

Annual Report, 1926

REPORT OF THE PECAN CULTURIST

Wilmon Newell, Director.
SIR: I hereby submit the following report of the Pecan Cul-
turist for the fiscal year ending June 30, 1926.
Respectfully,
G. H. BLACKMON,
Pecan Culturist.

The work of the department during the year has been a con-
tinuation of that reported for 1925.

NUT GROWTH

During the growing season of 1925 measurements were taken
of a larger number of varieties of pecans than in 1924, including
Bradley, Curtis, President, Schley, Stuart, and Success. All
trees producing the nuts measured were 11 years old except one
Curtis and the Success, which were five years old. The results
obtained by the measurements agree with those of 1924 with
two exceptions, one of the Schley and the other the five year
old Curtis and Success. The figures in Table X and the charts
show the behavior of the growing nuts, so far as the diameter
is concerned. The measurements showing the greatest rate of
growth were taken between June 24 and August 4 inclusive,

.4I 1B
ilbnr.! Jni M'. Ml-l
K '- ---V ] _p-y .. A u...
0 ii.

> .. .. !
^ - -^ --- { -

- -- i -,

Aug
* IP

e .

I I -
P- -

1- Cupfa; t I q.id. i
- 5urtl &"

:- ..

DATE
Fig. 5.-Rate of nut growth-Schley and Curtis varieties.

59R

60R Florida Agricultural Experiment Station

which would make the maximum growth in diameter take place
from about June 15 to August 15 as in 1924.

''"i ,, -I -

Ij

I^sO - .-

E/'' -,-- .-

n J/ 1- .t...t 1' -saw i
S/ /

10-'-"2 2- mrt it 11 y"

...,, -... I

V ,

seot. Ort.

cad.

Slb.-r

Fig. 6.-Rate

DATE
of nut growth-Stuart

and President varieties.

13 30 l s
'-

>5
-t .

I>----- --;
I /1' /
, / I /

S'* 1..- SuCe a b 7lu
, II i
Ii- r 11

* I i ,
- I

a 10

DATE
Fig. 7.-Rate of nut growth-Success and Bradley varieties.

During 1925 the rainfall at Baldwin was fairly well distrib-
uted thruout the growing season. Thus the resulting curve of
the growth of the nuts produced on the trees that were five
years old is not as irregular as that of 1924. The difference in
the Schley is that scab was controlled with a 4-4-50 Bordeaux

CI,
C

C

4

Annual Report, 1926 611l

TABLE X.-AVERAGE MEASUREMENTS OF PECAN NUTS DURING 1925
Increment
Average since last
Date Age No. Meas- Diameter measurement
1925 Variety of tree urements in mm. in mm.
4/28 Curtis ..........................11 yr. 59 2.4
Curtis ..........................--- 11 yr. 61 2.5
Curtis .......................... 5 yr. 50 2.7
Schley ..........................-------11 yr. 71 2.8
Stuart ..........................----- -11 yr.
President ....................-----11 yr. 26 2.5
Bradley .....---..........11 yr. 41 3.0
Success ........................ 5 yr. 15 2.9

5/13 Curtis ..--....-----.........-. 11 yr.
Curtis --------.........................11 yr. 51 3.3 .8
Curtis ... ------...................... 5 yr. 51 3.8 1.1
Schley ..........................------ 11 yr. 57 4.2 1.4
Stuart .....-------....................11 yr. 40 3.5
President ....................11 yr. 30 3.9 1.4
Bradley ..............---- 11 yr. 69 4.2 1.2
Success ................ 5 yr.- 16 4.2 1.3

5/30 Curtis .. ------.......................11 yr.
Curtis ..........................11 yr. 41 4.6 1.3
Curtis .......................... 5 yr. 41 5.7 1.9
Schley ..........................11 yr. 44 6.0 1.8
Stuart ..........................11 yr. 36 5.3 1.8
President ....................----11 yr. 41 5.5 1.6
Bradley .......--------....1 yr. 39 5.7 1.5
Success ........ ..------. 5 yr. 14 5.7 1.5

6/11 Curtis .... -------.....................11 yr.
Curtis ...----.......................11 yr. 50 6.4 1.8
Curtis .......................... 5 yr. 39 7.9 2.2
Schley ..........................11 yr. 50 7.6 1.6
Stuart ..------...................11 yr. 51 7.0 1.7
President ..........------.........11 yr. 51 7.0 1.5
Bradley ....... ..------ 11 yr. 43 7.4 1.7
Success .....--......--..... 5 yr. 10 8.0 2.3

6/24 Curtis ....-----..... --..............11 yr. 51 8.3 5.9
Curtis .... ----..................--..11 yr. 52 8.3 1.9
Curtis .......................... 5 yr. 51 10.7 2.8
Schley ..........................-------11 yr. 48 9.8 2.2
Stuart .------......................11 yr. 51 10.4 3.4
President .........------11 yr. 38 9.9 2.9
Bradley .-........-------11 yr. 38 10.2 2.8
Success ...........-.....------- 5 yr. 8 12.0 4.0

7/11 Curtis ..........................------11 yr. 52 12.1 3.8
Curtis -------.......................11 yr. 46 11.9 3.6
Curtis .......................---- 5 yr. 64 15.0 4.3
Schley ....-------...................11 yr. 45 14.3 4.5
Stuart .......................----- 11 yr. 51 15.0 4.6
President ......-------. .11 yr. 43 13.8 3.9
Bradley ..........---........:....11 yr. 52 12.7 2.5
Success ....................... ----- --- 5 yr. 8 16.6 4.6

62R Florida Agricultural Experiment Station

TABLE X.-AVERAGE MEASUREMENTS OF PECAN NUTS DURING 1925
-(Continued)
Increment
Average since last
Date Age No. Meas- Diameter measurement
1925 Variety of tree urements in mm. in mm.

7/25 Curtis ...............-..........11 yr. 54 16.8 4.7
Curtis ..-................-......11 yr. 60 16.7 4.8
Curtis .......................... 5 yr. 58 20.9 5.9
Schley ..........................11 yr. 56 19.5 5.2
Stuart .........................-11 yr. 51 21.1 6.1
President ......................11 yr. 49 18.1 4.3
Bradley ........................11 yr. 60 16.7 4.0
Success .......................-----. 5 yr. 6 24.1 7.5

8/3 Curtis ..........................11 yr. 59 20.9 4.1
Curtis ..........................11 yr. 60 19.9 3.2
Curtis .......................... 5 yr. 54 22.1 1.2
Schley ..........................---11 yr. 54 23.2 3.7
Stuart ..........................11 yr. 58 26.8 5.7
President ......................11 yr. 81 22.3 4.2
Bradley ................---........11 yr. 53 21.4 4.7
Success ........................ 5 yr. 48 28.4 4.3
8/18 Curtis ..........................---11 yr. 53 24.5 3.6
Curtis ..........................11 yr. 57 24.3 4.4
Curtis .......................... 5 yr. 51 25.7 3.6
Schley ..-----.......................11 yr. 59 26.0 2.8
Stuart ..---.....................-- 11 yr. 49 29.8 3.0
President ......................--- ---11 yr. 53 24.6 2.3
Bradley ........................------11 yr. 57 25.2 3.8
Success ........................ 5 yr. 49 30.7 2.3

9/4 Curtis ..........................11 yr. 49 27.2 2.7
Curtis .................... 11 yr. 50 25.4 1.1
Curtis .......................... 5 yr. 50 27.0 1.3
Schley ..............-----............11 yr. 49 28.7 2.7
Stuart ..........................11 yr. 48 33.5 3.7
President ................-.....11 yr. 52 29.6 5.0
Bradley ........................11 yr. 52 28.2 3.0
Success ........................ 5 yr. 49 33.5 2.8

9/16 Curtis .........................----- -11 yr. 44 27.6 .4
Curtis ........................11 yr.
Curtis .......................... 5 yr. 49 27.0 .0
Schley ..........................-------11 yr. 51 31.6 2.9
Stuart ..........................11 yr. 48 34.6 1.1
President -----....................11 yr. 53 32.7 3.1
Bradley ........................11 yr. 50 30.6 2.4
Success ........................ 5 yr. 47 34.7 1.2
10/3 Curtis ................-........11 yr. 50 28.2 .6
Curtis ..........................11 yr. 54 27.9 2.5
Curtis ................ .. 5 yr. 54 27.8 .8
Schley ....... ....-------11 yr. 55 31.5 -.1
Stuart .......................-11 yr. 53 36.2 1.6
President ......................11 yr. 50 33.7 1.0
Bradley ....................... 11 yr. 53 30.8 .2
Success .... -----.................... 5 yr. 57 35.3 .6

Annual Report, 1926

to which had been added one pound of arsenate of lead and one-
half pound calcium caseinate, sufficiently to permit the nuts to
develop to normal size, thus giving a complete growth curve for
this variety for 1925. Growth of pecan nuts as indicated by the
measurements is determined by the moisture and food supply,
insect pests, and diseases. Where moisture and food supply are
kept constant and insects and diseases are kept under control
there will be a normal growth and development of the nuts. Also
it is very evident from these studies that pecan orchards must be
cultivated, fertilized, and planted to cover crops in such a man-
ner that the trees will not suffer at any time from a shortage
of moisture and food supply.

VARIETY AND STOCK TESTS
The variety and stock tests being conducted on the horticul-
tural grounds at the Station are well under way, but as yet very
little can be reported. Since the 1925 report there has been one
pecan variety added to the variety orchard. The planting
is now made up of the following:
PECANS (Hicoria pecan) WALNUTS (Juglans)
5 Acme 5 Pabst Juglans regia
5 Bass 5 Randall 3 Placentia Perfection
5 Burkett 5 Rising 3 Pride of Ventura
5 Curtis 5 Russell 3 Seedling
5 Dependable 5 Schley 1 Rush
5 Farley 5 Simmons 3 Franquette
5 Frotscher 5 Success 2 Ehrhardt
5 -James 5 Teche Juglans nigra
5 Kennedy 5 Van Deman
5 Moneymaker 5 Stuart 2 Ohio
5 Moore 5 Zink (Big Z) 1 Stabler
2 Ten Eyck
2 Thomas
Juglans sieboldiana
3 Cordiformis Seedlings

A fairly heavy growth of cowpeas and Crotalaria striata were
turned into the soil of the variety orchard in the fall of 1925
and a crop of rye in the spring of 1926. A volunteer crop of
Crotalaria striata and one planted of Crotalaria sericea is quite
promising at this time.
In addition to the varieties and stocks that are being tested
at the Everglades Station and cooperatively at Davie, a few trees
were planted by a cooperative arrangement at Canal Point.

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Florida Agricultural Experiment Station

FERTILIZER EXPERIMENTS
There has been no change in the number of fertilizer experi-
ments reported in 1925 that are being conducted in cooperation
with the Chemist.
The yield in 1925 was quite satisfactory and interesting vari-
ations noted, but as yet there has not been sufficient time to pro-

Fig. 8.-Type of pecan orchard in which fertilizer experiment is being con-
ducted. This is located in Jefferson County. The variety i- Schley.

duce definite results. In cooperation with the Bureau of Plant
Industry of the U. S. Department of Agriculture, the two coop-
erative fertilizer experiments in Duval County are being con-
tinued.
REJUVENATION EXPERIMENT
There has been a very marked improvement in the condition
of the trees in the orchard where the rejuvenation experiment
is being conducted. Many of the trees have a fair crop of nuts
set this year.
ROSETTE EXPERIMENT

The rosette experiment being conducted in Bradford County
in cooperation with the Chemist and Plant Pathologist is pro-
ducing encouraging results. However, the work has not been
going long enough for a definite report.

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Annual Report, 1926

DISEASE CONTROL
In cooperation with the Plant Pathologist a spraying experi-
ment for the control of pecan scab was conducted cooperatively
in Duval County in the pecan orchard of J. H. Wells. The ex-
periment was so planned as to give some idea as to the effect
of different treatments that have been considered as advisable
to use in the probable control of pecan scab. The materials
used and the dates applied are given in the following outline:

SPRAY SERIES I.
1. A dormant spray of copper sulfate, 8 pounds to 50 gallons water,
was applied March 4, 1925, which was just before the buds forced
into growth.
2. 4-4-50 Bordeaux.
/2 lb. calcium caseinate, May 13, 1925.
1 Ib. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.
SPRAY SERIES II.
1. Dormant spray of lime-sulphur, 10 gallons concentrated to 50 gal-
lons water, was applied March 4, 1925, which was just before the
buds forced into growth.
2. 4-4-50 Bordeaux.
% Ib. calcium caseinate, May 13, 1925.
1 lb. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.
SPRAY SERIES III.
1. All husks, leaves, and fallen twigs were cleaned away and plowed
under and a dormant spray of copper sulfate, 8 pounds to 50 gal-
lons of water, was applied March 4, 1925, which was just before the
buds forced into growth.
2. 4-4-50 Bordeaux.
% Ib. calcium caseinate, May 13, 1925.
1 lb. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.

SPRAY SERIES IV.
1. All husks, leaves and fallen twigs were cleaned away and plowed
under and a dormant spray of lime sulphur, 10 gallons concentrated
to 50 gallons water, was applied March 4, 1925, which was just
before the buds forced into growth.
2. 4-4-50 Bordeaux.
% lb. calcium caseinate, May 13, 1925.
1 lb. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.

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Florida Agricultural Experiment Station

SPRAY SERIES V.
1. No dormant spray and no clean up.
2. 4-4-50 Bordeaux.
% lb. calcium caseinate, May 13, 1925.
1 lb. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No. 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.
SPRAY SERIES VI.
1. No dormant spray and no clean up.
2. 4-4-50 Bordeaux.
/2 lb. Flour, May 13, 1925.
1 lb. arsekoll.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.
SPRAY SERIES VII.
1. No dormant spray and no clean up.
2. 4-4-50 Bordeaux.
% lb. fish oil, May 13, 1925.
1 lb. powdered arsenate of lead.
3. Same as No. 2. June 17, 1925.
4. Same as No 2. July 15, 1925.
5. Same as No. 2. August 26, 1925.

It will be observed that different materials were used as stick-
ers and spreaders. While all the materials used gave fairly
good results, the calcium caseinate caused the Bordeaux to ad-
here to the foliage, nuts, and branches a longer period than any
of the others used. No detrimental effects were experienced at
all in using any of the stickers and spreaders.
A portion of the trees sprayed were partly top-worked to
other varieties. Excellent results were had in controlling scab
sufficiently to permit the nuts to develop and mature to normal
size while the nuts on the unsprayed trees scabbed so badly that
practically all of them shed before maturity. The 16 trees with
full top that were sprayed produced an average of 17.1 pounds
of marketable nuts per tree, while practically none of those on
the unsprayed trees were marketable.
A duster was purchased during the spring of 1926 and put
into use in Jefferson County. Several dusts are being used ex-
perimentally to control pecan scab, but as yet nothing definite
can be reported.
INSECT CONTROL
This work is being conducted in cooperation with the Depart-
ment of Entomology and includes a study of the life history and
control methods of certain pecan insects. Two spraying experi-

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Annual Report, 1926 67R

ments were conducted in Duval County. Excellent results were
had in the control of the leaf case-bearer by the use of one pound
of arsenate of lead and three pounds lime to 50 gallons water or
by adding it to Bordeaux in the same proportion. Two appli-
cations, made about July and August, gave a somewhat better
control than did one. The duster mentioned above also is being
used in the experimental work of insect control, but no definite
results con be reported at this time.

COVER CROP
The cover crop work in cooperation with the Department of
Agronomy, reported in 1925, is being continued.

Florida Agricultural Experiment Station

REPORT OF PLANT PATHOLOGIST

Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Plant Pathology for the fiscal year ending June 30, 1926.
Respectfully,
O. F. BURGER,
Plant Pathologist.

During the past year the Department of Plant Pathology has
been working in cooperation with the State Plant Board on
scaly-bark of citrus, citrus canker, fungous control of the cit-
rus aphid, and diseases of coconuts. We have also continued
our cooperation with the Office of Truck, Cotton, and Forage
Crop Diseases, of the United States Department of Agriculture,
on the control of tomato nailhead rust.

CITRUS CANKER
The laboratory work is being carried out by Kenneth W.
Loucks. Most of the time was spent in trying to inoculate seed-
lings by planting seeds in soil which had been inoculated with
Bacterium citri. The seeds were kept at various temperatures.
The seeds germinated, and as the young trees pushed up thru
the soil they did not show infection.
The optimum temperature for the growth of the bacterium
was found to be about 250 C.
Some kumquat seeds were planted in test tubes and when
they sprouted they were inoculated with Bacterium citri. In-
fection showed up in five days.
Young grapefruit plants sprouted in test tubes and when in-
oculated were placed in various temperatures. Those tubes
which were held at 20 C. showed infection first. More work
is being done on the life history of the bacterium.

MELANOSE
Some more groves were sprayed with Bordeaux-oil emulsion
for the control of melanose, with practically the same results as
reported in Bulletin 167.

COLORING OF CITRUS FRUITS
This work was carried on by L. E. Dupont, whose report fol-
lows:

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Annual Report, 1926

The results obtained, together with the experiments leading
to them, have been shaped in the form of a thesis which has been
presented to the faculty.
The results of this work are not what had been anticipated,.
due partly to the difficulty of securing green fruits and partly
to the small amount of investigation in this field.
With the results at hand, however, there is little doubt that
a successful commercial application can be made. The type of
burner in use at present is faulty in that the combustion of kero-
sene is too complete. The concentration of ethylene should be
more carefully regulated. More emphasis should be laid on
such beneficial mechanical injury as sudden cooling, ultra-violet
light, etc. The susceptibility of the fruit to attack by fungi
and bacteria should be investigated following any treatment,
since the appearance of the fruit after being subjected to a
chemical and mechanical treatment is not conclusive evidence of
the success of the process.
The action of different substances and their effectiveness in
producing "coloration" in the orange gave the following results:
Chemicals having a tendency to increase respiration (ben-
zene, toluene, acetic acid, ethyl acetate, etc.) act with remark-
able rapidity, but the taste they impart to the fruit renders their
use impossible.
Unsaturated hydrocarbons are of little value in increasing
ripening. Two exceptions to this statement must be made, how-
ever, as both ethylene and acetylene in concentrations of 1/1,000
gave promising results.
Aldehydes are too caustic and injure the texture of the rind,
but acrylic aldehyde at a concentration of 1 percent acted fav-
orably.
Combining the desirable effect of both ethylene and acrylic
aldehyde, a process has been devised whereby the time of col-
oring has been reduced from four and a half days to three days.
It is not possible with the data on hand to ascribe to these
reagents any action that would indicate direct combination with
chlorophyll. iThey must still be regarded (proposed by Denny)
as catalysts hastening a purely biochemical reaction occurring
as the result of normal metabolism.

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Florida Agricultural Experiment Station

PECAN SCAB

This work was carried on by R. E. Nolen, who was working
during the past year in the University of Wisconsin under the
immediate supervision of Dr. Keitt.
During the summer of 1925 the work on pecan scab, as begun
in 1924, was continued and consisted of the gathering of data
as to the distribution of the diseases on the tree and on the in-
dividual leaves, the gathering of data as to the relative experi-
ments and in assisting the Pecan Culturist in carrying on experi-
ments in controlling the disease.
In the fall the work was moved to Madison, Wisconsin, and
as soon as possible seedlings were started and grafted trees
planted. During the winter a limited number of germination
experiments were made and considerable work done in trying
to find a medium upon which the organism would sporulate. As
soon as the trees were in condition to be used, inoculation ex-
periments were commenced in order to find out the optimum
temperature for infection and the optimum and minimum peri-
ods of saturation necessary for infection to take place; the cause
of resistance; and cross inoculation experiments with other
plants and other closely related fungi on pecans. These experi-
ments are still in progress and at present it is impossible to
draw any final conclusions.
Pecan scab seems to be well distributed thruout the tree, altho
in badly infected trees the lower portions are more severely in-
fected. There seems to be no relation between the severity of
the infection and the position of the leaflet on the petiole. Most of
the lesions are on the mid-ribs and veins. The petioles are sub-
ject to severe infection.
During 1925 the Moore variety seemed to gain in susceptibil-
ity. Altho this was not an epidemic year, Moore showed more
infection than during 1924.
The infection experiments being carried on at Madison are
conducted in an inoculation chamber where the air is saturated
and the temperature is controlled. After being left in this
chamber for a given number of hours after inoculation, they are
removed either to the greenhouse or to a smaller chamber in
which the humidity and temperature are controlled. At the
present time where the inoculated tree was kept in a saturated
atmosphere for lessthan 20 hours infection has been secured at
240 C. Infection has been secured at 20, 22 and 280 C. when the

Annual Report, 1926

inoculated tree was kept in a saturated atmosphere for 48 hours
immediately following inoculation. No infection-has been se-
cured at 100, nor when kept in a humidity of 90 per cent for
four days immediately following inoculation. No infection has
been secured on the pecan from spores of Venturia inaequalis,
the organism causing apple scab, at 100 C. The negative results
should not be considered as final since the experiments are under
way and in some cases the entire length of time for the possible
necessary incubation period has not elapsed.
Spore germination has been secured at 6' and at 320 C. The
optimum temperatures are 200 and 22 C.
The incubation period in the field as determined thru experi-
ments at Gainesville, Florida, is from 4 to 21 days, while in the
greenhouse as determined at Madison is from 7 to 15 days.
SCALY BARK
Erdman West carried on these investigations and following
is his report:
The investigation of scaly bark of citrus was carried on this
year both in the field on the East Coast and in the laboratory
at Gainesville. The work in the field consisted in observing the
progress of the disease and the results of control methods; the
work at Gainesville included attempts to isolate the organism,
inoculation experiments and some histological studies of young
lesions.
In the groves at LaGrange and Indianola the first new infec-
tions occurred between June 1 and June 24. The spots on the
water sprouts varied from tiny water soaked areas 2 to 5 milli-
meters in diameter to larger yellowish spots 4 to 10 millimeters
across with hard centers 3 to 5 millimeters in diameter. A very
few nailhead spots occurred on the fruit at this time. All of
the new spots on the bark were on wood of the previous season's
growth. No scaly bark infection was visible on 1925 growth
until the middle of October. Either the disease does not attack
fresh sprouts or the incubation period is so long that the infec-
tion is not visible for three or four months. Spots observed in
June reached a diameter of 10 to 15 millimeters by October and
had become red-brown in color and brittle in texture.
Scaly bark seems susceptible to control by pruning in conjunc-
tion with good grove care. Groves showing the disease in the
severest form were receiving a minimum care, while those under

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Florida Agricultural Experiment Station

good grove practice were not being damaged, altho occasional
infection could be found. One grower, considering the spray-
ing and pruning superfluous, stopped these measures two years
ago. In 1924 he lost a few boxes of fruit. In 1925, he lost
about 50 percent of his crop from this cause and his trees showed
a general infection on the branches. His neighbor who con-
tinued control measures, has a healthy grove and lost no fruit.
Attempts to isolate the causal organism from lesions on the
bark, leaves and fruit were made. One hundred and twenty-nine
series of plates were poured and the organisms found isolated
and determined. Colletotrichum gloeosporioides and Phomopsis
citri appeared in about 90 percent of the plates. Various other
organisms such as Bacteria, Penicillium, Fusarium and Melan-
ospora appeared irregularly and were undoubtedly contamina-
tions or secondary.
A Cladosporium was isolated in five cases, which compares
well with the fungus described by Dr. Fawcett as being the
causal organism.
Four attempts to secure artificial infection with the Clado-
sporium and also with pieces of diseased material were made on
sweet seedling nursery stock out of doors at Gainesville during
1925. None of these were successful with lack of moisture prob-
ably the limiting factor. In April two more attempts were
made, one with a culture of Cladosporium and one with pieces
of diseased bark. The results have been negative up to this
time.
Several hundred paraffin sections were made of young spots
on material killed in the field in 1925. Examination of these
sections stained in various ways has not revealed the presence
of any organism in the tissue. Cells in the infected areas are
filled with a gum or resin. These gum pockets include only the
parenchyma cells between the phloem and the epidermis but in-
clude neither of these tissues. The cells fill with gum faster
several layers deep than directly beneath the epidermis. Also
the gum filled area extends for about 10 cells in advance of the
apparent infection. The internal symptoms were similar for
spots on bark, fruit, and leaves. On the latter the gum extended
the entire thickness of the leaf.

72R

Annual Report, 1926

COCONUT DISEASES
The following is the report by J. L. Seal, who is in charge of
the coconut bud rot disease project:
The work on coconut diseases which was carried on at Miami,
consisted chiefly of making isolations from diseased plants; altho
some time was expended in making a limited amount of mor-
phological and physiological studies of fungi isolated from these
diseased palms. Since September, 1925, the work has been con-
ducted at Gainesville and limited primarily to laboratory work;
studies being made upon the morphology and physiology of the
84 strains of Phytophthora, isolated from the 1,142 specimens
received to date, as exhibited on various agars.
In some of these studies very definite and different morpho-
logical and physiological reactions have been noted in the vari-
ous strains. While the true taxonomic position of these Phy-
tophthora cannot be definitely indicated at present, apparently
there are several groups (physiological races) or possibly spe-
cies concerned. Some of these Phytophthora strains have been
compared in culture as well as morphologically with Phytoph-
thora faberi Maub., obtained from Dr. Otto Rankin and Mr. C.
M. Tucker, which were isolated from diseased coconut palms in
the Philippine Islands and Porto Rico, respectively. Some of
the Florida strains are identical or agree very closely morpho-
logically and physiologically with Phytophthora faberi Maub.,
while others seem to differ materially.
My object is to get these obviously physiologically different
Phytophthoras into groups and study them to establish their
identity. A limited amount of morphological and pathogenic
work has been completed and further studies are under way.
These strains were selected because they were quite different
in growth characters. Groups of five plants were used; group
I was inoculated with strain A; group II, inoculated with strain
B; and group III was held as a check. The plants were inocu-
lated on February 24 and the disease was evident on April 27.
Successful inoculation was accomplished in every case and typi-
cal lesions as described for Phytophthora faberi were produced.
The same type fungi have been recovered from the inoculated
plants, thus establishing the pathogenic nature of the organ-
isms. The checks have remained free of any signs of disease.
An attempt has been made to correlate the climatic conditions
of Southeast Florida with the findings of coconut diseases; there

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Florida Agricultural Experiment Station

apparently is no correlation between temperature and outbreaks
but a very definite correlation between amount of rainfall and
outbreaks.
TRUCK CROP DISEASES
The tomato disease project and cucumber diseases are being
investigated by Dr. G. F. Weber. The field work in tomato dis-
eases is being conducted by Stacy O. Hawkins near Miami, and D.
G. A. Kelbert near Bradenton. In both places the growers have
supplied a laboratory for the work. The growers have shown
a willingness to cooperate and have supplied money and equip-
ment to carry on the investigations.
The identification of specimens and correspondence have been
about the same as last year, consuming considerable time.
Numerous collections have been made and a large number of
specimens have been added to the herbarium.
Two papers were presented at the A. A. A. S. meetings at
Kansas City. One, "Plus (+) and Minus (-) Strains of the
Mucor Blakeslea trispora Thax." was presented before the Bo-
tanical Society of America. The other, "Downy Mildew Sclero-
spora graminicola (Sacc.) Schroet) on the Everglade Millet
(Chaetochloa magna (Griseb) Scribn)" was presented before
the Phytopathological Society.
During the year Blakeslea trispora was found contaminating
a number of petri dish cultures. Isolations were made from
these contaminations and both plus and minus strains of this
fungus were found to be in the culture. This is the first time
both strains of this fungus have been isolated. The Mucor was
associated with the sclerocia of Corticium stevensii. A second
isolation of both strains of the fungus was made from poured
plates containing portions of diseased cucumber leaves.
A condition prevalent in truck crops during the season of the
past year is unique in that there has been a scarcity of diseases
that are usually very important. In fact, specific diseases
which during previous seasons have been factors determining
the profit derived from many crops, have been conspicuously
absent. There are undoubtedly many reasons why different
diseases behave in this way, but with the meager information
at hand it is impossible at the present time to determine the
exact reasons.
During the past five years nailhead rust (Alternaria solani)
on tomatoes has been of a very destructive nature over prac-

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Annual Report, 1926

tically all of the tomato growing sections of the state. This
year its importance is negligible, it causing considerably less
than 1 percent loss to the growers. Late blight (Septoria lyco-
persici) collected in several localities last year was not found
this year. Leaf mold (Cladosporium fulvum) was not nearly as
important as last year.
Downy mildew (Pseudoperonospora cubensis) of cucumbers,
the worst disease of that plant in Florida, usually present and
destructive, was merely present in a few scattered places during
the past season and in no way was important. On the other
hand, powdery mildew (Erysiphe cichoracearum) was more
common and destructive than it has been in the past five years.
The control of the downy mildew of cucumbers was conducted
on much the same scale as last year in that about six acres of
cucumbers were sprayed and dusted with various kinds of
spraying and dusting material. Five applications were made,
all with hand dusters and knapsack sprayers. Owing to the scar-
city of the fungus nothing in the way of results can be reported.
In a field near LaCrosse angular leaf spot developed to a con-
siderable extent and an attempt was made to check the disease
after it had appeared in the field, affecting about 50 percent of
the plants. The disease was well distributed over the field be-
fore any fungicides were applied. Four applications of dust
and spray were made and check plots were left. On the plots to
which the fungicide was applied the disease was held in check
in a satisfactory manner. The check plots were completely
killed.
During the year more than 100,000 seed of tomatoes, eggplant,
and pepper were treated with disinfectants for the purpose of
determining the most desirable disinfectant to use for this pur-
pose, both in reference to disease control and to the safety and
availability of the same to the grower. These treated seed
were planted in sterilized soil in flats in the greenhouse. It
seems that the best recommendation to make at this time is the
use of corrosive sublimate, 1 to 1,000. The seeds should be
treated for about eight minutes.
The experiments on the control of nailhead rust of tomatoes
were conducted in relatively the same manner as last year, ex-
cept that they were duplicated on the West Coast in the Braden-
ton section. The disease did not appear in the experimental
plots until late in the season. In all about 20 acres of tomatoes

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were sprayed and dusted in these plots, but owing to the scar-
city of the disease nothing in the way of value of the different
fungicides as a control for this disease was determined. Numer-
ous varieties were tested in different localities of this state to
determine their susceptibility to this disease and it was found
that the Marvel still remained the most resistant type of tomato,
with Marglobe, Globe and Cooper's Special showing some resist-
ance among the 45 varieties in these plots.
CITRUS BLIGHT
The citrus blight work is being carried on by Dr. A. S.
Rhoads who is located at Cocoa. The growers in the Cocoa dis-
trict have cooperated in this work, and have furnished consid-
erable funds to get the work started.
The outstanding accomplishment of the past year's work on
citrus blight has been the planting of over two acres of experi-
mental grove on Merritts Island on a tract of land leased for a
period of years sufficient to justify the experiment. Prior to
this, experiments on budding citrus trees with budwood from
various blighted trees were conducted principally in the three
different groves. One of these groves in which 50 sour orange
trees budded with buds from blighted orange trees had been set
out in January, 1925, to replace blighted trees that had been re-
moved, was sold and another grove was placed on the market
for sale. In order therefore to accomplish something definite in
regard to the question as to whether or not citrus blight is a
disease that can be transmitted by budding it was necessary
that the experimental budded trees could be set out and main-
tained in grove formation for a period of 10 or more years.
After running a survey to locate the tract of land leased for
this purpose, the land was cleared and grubbed, plowed, har-
rowed, and planted to velvet beans, which were disked in before
the trees were set out. The land was then surveyed and staked
out for the planting and the experimental trees on hand moved
from the various groves they were in, set out in January, 1926,
according to a definite planting plan, watered, and later basined
and mulched to conserve the soil moisture during the dry period.
The spring application of fertilizer was also made and aphids
combatted as became necessary.
The finished planting comprises 16 rows of 11 trees each,
spaced 22 feet apart each way. The odd-numbered rows con-

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Annual Report, 1926

tain the check trees, a large part of which were budded by Dr.
Rhoads from healthy trees and the balance purchased from a
nursery. The even-numbered rows contain trees budded from
various typically blighted trees, representing the propagation of
at least 15 different blighted trees. All trees budded from any
particular blighted trees were set out together in one row or
part of a row. After this experimental grove was planted, diam-
eter measurements were made on each tree at a point above the
bud union, the height of the measurements also being noted.
The results of a field reconnaissance made of a large part of
the citrus section of the state during April and May, 1925, show
that in addition to the East Coast, wilt or blight occurred in the
central part of the state, on deep sandy soils, on slopes or in
groves where the soil had become compacted beneath the super-
ficial layer stirred by cultivation. This survey shows that in
the balance of the citrus section of the state investigated the
trouble known as blight generally is of a very rare and sporadic
occurrence. This trouble has been found in one isolated grove
as far north as six miles south of Jacksonville.
Of the large number of buds and grafts successfully made two
years ago virtually all have lived but a few budded trees that
died from drought, after transplanting in January, 1925. In
this time there has not been obtained any evidence whatsoever
to indicate that the chronic wilt or so-called "blight" is trans-
missible by budding and grafting and it is firmly believed that
the trees so budded or grafted will make as fine trees as any lot
grown under the same conditions.
From the investigations thus far conducted the chronic wilt,
or so-called "blight" of citrus trees is believed to be purely a
physiological trouble caused by extremes in soil moisture condi-
tions rather than by a disease in the usual sense of the word,
that is one caused by a pathogenic organism. This trouble ap-
pears to be caused most frequently by a deficiency in the sup-
ply of soil moisture available during the dry season of the year,
but often also by an excessive amount of soil moisture resulting
from the prolonged saturation of areas of grove lacking ade-
quate drainage and may be intensified by the occurrence of the
former condition after the latter one. The occurrence of citrus
blight clearly is greatly expedited by neglect in care of the grove.
A progress report of the investigations on citrus blight was
prepared for the annual meeting of the State Horticultural So-

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city; also an address on "The Classification and Agricultural
Value of the More Important Soil Types in South Florida, with
Special Reference to Citrus Culture", which was accompanied
by a large exhibit of the different soil types.
POTATO DISEASES
Potato disease work is conducted at Hastings. The growers
have shown a fine spirit of cooperation. Laboratory space is
being supplied by the growers as well as space for field plot
work. Dr. L. O. Gratz is in charge of this work and the fol-
lowing is his report:
The Assistant Plant Pathologist investigating diseases of
white potatoes spent from July 15 to October 1 in Aroostook
County, Maine, in connection with the certification work of the
seed potatoes and further familiarizing himself with their meth-
ods of handling our seed potatoes, and the disease problems
which are encountered.
While in Maine a cooperative experiment was conducted with
the Experiment Station of that state on Alternaria spotting of
tubers. This experiment determined how field inoculation of the
tubers takes place and pointed out the temperature and climatic
factors which are favorable for the development of this disease.
An abstract of a paper reporting this work is given in Phyto-
pathology 16: 68, 1926.
The experiments in the Hastings section consisted of seed
treatments, symptoms, and yields of Maine selected samples
diseased with mosaic, spindle tuber, and verticillium wilt, and
variety tests. Unless otherwise stated the Spaulding Rose 4
was the variety used in these experiments.
In the seed treatment experiments various organic mercuric
compounds were compared with corrosive sublimate, and with
both diseased and clean tubers. Very little benefit was noted
from any of the treatments except Semesan, which gave mate-
rial increases in yield. These treatments will be repeated next
year.
Following are the average yields obtained from the spray and
dust experiments for the different plots:

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TABLE XI.-SPRAY'AND DUST EXPERIMENTS WITH POTATOES

Replica- Calculated Yield in Percentages Calculated Yield in Percentages
tions Barrels per Acre Barrels per Acre

Marketable Unmar- Marketable Unmar- Marketable Unmar- Marketable Unmar-
No. 1 No. 2 ketable No. 1 No.2 ketable No. 1 No. 2 ketable No.1 No. 2 ketable

Copper-lime Dust PLOT I 4-4-50 Bordeaux Mixture
7 35.9 14.9 6.3 62.9 26.1 11.0 34.8 16.3 8.4 58.5 27.4 14.1
Copper-lime Dust __Check
8 31.9 15.3 7.3 58.6 28.1 13.3 30.9 16.4 7.7 56.2 29.8 14.0
4-4-50 Bordeaux Mixture I Check I
5 38.5 16.0 5.4 64.3 26.7 9.0 1 36.2 17.2 5.8 I 61.2 29.1 9.7
UI | Copper-lime Dust ) PLOT III 4-4-50 Bordeaux Mixture
8 38.8 13.8 5.0 67.4 23.9 8.7 51.4 14.2 5.3 72.5 20.0 7.5
Copper-lime Dust I Check
6 37.3 12.4 5.0 68.2 22.7 9.1 _31.1 15.2 5.5 60.0 29.4 10.6
4-4-50 Bordeaux Mixture Check
3 56.8 13.2 6.2 74.6 1 7.3 8.1 43.0 12.2 4.6 171.9 20.4 7.7

Florida Agricultural Experiment Station

Very little benefit was derived from the treatments in Plot I.
This was due to the fact that but three applications were made,
and these within a month before digging. This plot was plant-
ed and dug early and late blight was not a factor.
Six applications were made on Plot II. When comparing the
dust with the liquid or with the check, and the liquid with the
check a decided benefit is at once observed from either, but the
largest increases were found where the vines were sprayed
with Bordeaux mixture. It is questionable, however, if the
growers will adopt spraying as long as good results are obtained
by dusting. This is because of the nuisance of mixing and ap-
plying the wet materials properly, and the comparative ease of
using the dust. The life of a sprayer, where a high pressure is
absolutely essential, is very short and with existing labor con-
ditions, it is evident that the duster is the better adapted for
our use. With further refinements in dusts and dusters and a
greater thoroness in application, better results can be expected.
Tubers were selected in Maine, from a particular strain of
seed stock, from hills which were diseased with spindle tuber
and another sample diseased with verticillium wilt. These lots
were planted in Florida and compared with healthy tubers of
the same strain in an experiment consisting of six replications.
Following are the yields obtained:

SCalculated Yield in
Sample Barrels per Acre Percentages
Marketable (Unmar- Marketable Unmar-
_I No.1 No.2 Iketable No. 1 No. 2 ketable
Healthy .......................... 26.1 14.4 3.3 59.6 32.9 7.5
Verticillium Wilt .......... 19.2 15.9 3.6 49.6 41.1 9.3
Spindle Tuber .............. 0.9 3.6 2.5 12.9 51.4 35.7
It is evident from these figures that the spindle tuber disease
is extremely detrimental to good yields. Not over 2 percent of
the hills in the wilt samples actually exhibited symptoms of the
disease, but judging by the yields, the vitality of the stock was
much impaired.
Bliss Triumphs, diseased with mild mosaic, were compared
with healthy tubers of the same stock and a one-third decrease
in the yield was observed. The healthy lots yielded 50 barrels
per acre, and the mosaic samples but 34 barrels.

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In the variety tests six replications were planted of the varie-
ties given below. The average yields and percentages as to
grade follows:
TABLE XII.-YIELDS AND PERCENTAGES IN POTATO VARIETY TEST.
Calculated Yield in
Variety Barrels per Acre j Percentages
Marketable Unmar- Marketable |Unmar-
No. 1 No. 2 ketable No. 1 No. 2 1 ketable

Green Mountain (Me.).. 40.1 8.7 1.8 79.2 17.2 3.6
Irish Cobbler (Me.)..... 41.6 10.9 2.8 75.2 19.7 5.1
Bliss Triumph (Nebr.) 43.9 14.1 3.1 71.2 23.1 5.7
Golden Russet (Mich.).. 34.8 10.2 1.9 74.2 21.8 4.0
Spaulding Rose No. 4
(Maine) ...................... 34.2 15.4 3.0 65.0 29.3 5.7
Spaulding Rose No. 3
(Wisconsin) .............. 29.9 16.3 3.1 60.6 33.1 6.3

It will be observed that the Spauldings were decidedly lower
yielders than most of the other varieties, and produced a small-
er percentage of primes than the others. All of these varieties
were of the best certified stock obtainable.
Variety tests were also conducted at the Everglades Experi-
ment Station at Belle Glade and resulted as follows:
TABLE XIII.-YIELDS IN POTATO VARIETY TEST AT EVERGLADES STATION.

I Calculated Yield in
Variety Barrels per Acre
I Marketable (Unmar-
INo. 1 No.2 ketable

Bliss Triumph
Lot No. 1 (Nebraska) 63.2 10.0 3.3
Bliss Triumph
Lot No. 2 (Nebraska) 47.1 12.9 4.3
Green Mountain (Me.).. 52.7 15.1 4.4
Irish Cobbler (Me.)...... 67.5 10.3 3.1
Golden Russet (Mich.).- 37.8 18.5 7.1
Spaulding Rose No. 4
(Maine) ....... ...... 31.4 13.5 6.3

Marketable
No. 1 No. 2

82.6 13.1

73.2
73.0
83.4
59.6

61.3

Percentages

20.0
20.9
12.7
29.2

26.4

Experiments were

also conducted at the Everglades Station

on dusting with copper-lime dust. Blight was not a factor and
the benefits from dusting were not demonstrated.

Unmar-
ketable

4.3

6.8
6.1
3.9
11.2

12.3

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Florida Agricultural Experiment Station

STRAWBERRY DISEASE WORK
This work is being carried on in cooperation with the State
Plant Board. Dr. A. N. Brooks is in charge and the following
is his report:
In response to requests from many of the strawberry growers
of the state for work to be done upon strawberry diseases, the
Florida State legislature passed an appropriation starting July
1, 1925, for the carrying on of this work.
Since Plant City is the center of the largest strawberry grow-
ing area of the state, it was chosen as the headquarters for the
work, and a laboratory was established there, with sufficient
equipment to carry on studies upon strawberry diseases. An in-
vestigator was appointed and sent to Plant City. An acre of
land was leased and planted to 25 varieties of strawberries in
an attempt to secure a variety which might be freer from trouble
than was the Missionary. A duplicate patch was established
at Starke, Florida.
During the first part of the season much time was spent in
visiting the strawberry patches in Hillsboro County so as to
become acquainted with the methods of culture employed; to
find out if there was any trouble arising from plant diseases; to
become acquainted with the growers, and also to estimate the
acreage planted to strawberries around the various strawberry
centers, Plant City, Dover, Sidney, Turkey Creek, Lakeland,
Galloway, Kathleen, Bowling Green, and Wauchula.
During the latter part of October, 1925, a request came from
a Wimauma grower for an inspection of his strawberry patch
and for information concerning a possible remedy for the
trouble occurring there. In a field which had been rented by
the grower and planted to strawberries in September, the plants
were yellowing and dying off after having made a good growth
for two or three weeks.
The field was visited and the plants inspected by the County
Agent and the writer. No insects were present on the plants
and the condition of the plants did not seem to be due to fun-
gal or bacterial parasites (afterwards definitely proven by nega-
tive results from attempts to isolate organisms' from the affect-
ed leaves). Rather, it appeared that the plants were starving
from a lack of nitrogen. At least, the trouble seemed to be in
the soil. Inquiry brought out the fact that the field had been

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Annual Report, 1926

limed heavily with rock lime four years previously. Small
pieces of the lime could be seen in the soil. The writer suggest-
ed the possibility that the lime accounted for the condition of
the plants and suggested the use of a nitrogen fertilizer to over-
come this condition. Forty-eight of the affected plants, in every
stage of yellowing from slight to very severe were dug up, car-
ried to the State Plant Board's variety patch near Springhead
and set in soil that had not been limed. All of the plants sur-
vived and as the new leaves appeared they were of a normal
green color. The old leaves, however, did not become green but
remained yellow until they finally died off. Two other trips to
Wimauma later in the season showed that the plants in this
patch had not improved but were still stunted in growth and
yellow or dead. From a standpoint of fruit production the
patch was worthless, while the plants had been transplanted to
the State patch were bearing fruit heavily. On March 2, 1926,
28 of these dwarfed, yellowed plants were removed to the State
patch. These plants also grew out of the yellowed condition.
On a strawberry patch near Midway, there were areas where
the plants showed a similar yellowed condition. These areas
in the field, the writer found out, were the spots where rock
lime had been piled previous to broadcasting it over the field 12
years before. The grower had attempted several means of
counteracting the effect of the lime by adding plenty of stable
manure, leaves, etc., to the areas, but the effect of the lime still
persisted.
In further visits to various patches of Hillsboro County, dur-
ing the fall of 1925, the writer asked each grower if he had any
experience with limed soil affecting the growth of strawberry
plants. Out of 250 growers, only one seemed to feel that lime
had benefitted his crop, the others were either neutral or strong-
ly against the use of lime for strawberries.
From these observations and from the results of the trans-
plantings of strawberry plants from limed to unlimed soil, the
writer concludes that most Florida strawberry land should not
be limed, but if the grower feels that the land should be limed
it is best to experiment with a small tract of land and even
then to use the lime sparingly.

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Florida Agricultural Experiment Station

APHID DISEASES
The study of the entomogenous fungi attacking citrus aphid
was made by W. A. Kuntz, whose report follows:
The work during the past year consisted of a further study
of the fungous parasites of Aphis spiraecola. It was soon found
that the fungi Cephalosporium sp. and Cladosporium sp. are not
very great factors in the control of the citrus aphid. Cephalo-
sporium sp. was grown in artificial cultures and sprayed in
groves but it was unable to control the pest. Cladosporium sp.
seems to grow on any dead aphid but was not seen to attack liv-
ing aphids.
The fungus Empusa fresenii is regarded as the most effective
fungous parasite of the citrus aphid found in Florida. Studies
have been carried on in the field trying to ascertain the rate of
reproduction and effectiveness as a controlling agent. It was
found that after the fungus Empusa attacked a colony of aphids
it was only a matter of a few days until the colony was de-
stroyed.
From field data it is estimated that the damage done by the
aphid this spring was about 15 percent as great as done last
year. This is thought to be due to the cool prolonged spring
which held back the new growth; and also the drought in April
and May which had a like effect on the citrus trees.
The fungus Empusa was not active in the screened cages nor
in the field until about April 10. This seems to the writer that
growth and distribution of the parasite depends upon tempera-
ture and moisture.

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Annual Report, 1926

REPORT OF THE VETERINARIAN
Wilmon Newell, Director.
SIR: I submit the following report for the Department of
Livestock Diseases for the fiscal year ending June 30, 1926.
Respectfully,
A. L. SHEALY,
Veterinarian.

The Department of Livestock Diseases was created in the Ag-
ricultural Experiment Station on July 1, 1925, as a result of
funds having been appropriated for such investigational work
by the 1925 session of the State Legislature.
On July 1, 1925, Dr. D. A. Sanders began his work as Assist-
ant Veterinarian.
The work in this department has been carried out on two,
major and two minor projects. The major projects have been
salt sickness in cattle and Manson's eye worm of poultry. The
minor projects have been infectious mastitis in cattle (infec-
tious inflammation of the udder) and "leeches" in horses.

SALT SICKNESS IN CATTLE
The disease called "salt sickness" in cattle is found occurring
most frequently in range cattle, but is occasionally found in cat-
tle more closely confined. The condition seems to be more prev-
alent in certain sections of the state than in others.
The disease is recognized by the animal becoming very un-
thrifty, with gradual emaciation, rough coat, and in severe
cases extreme loss of flesh. There is a gradual loss of appetite
as the disease progresses.
Detailed observations have been carried out at the Agricultu-
ral Experiment Station with five cases of so-called "salt sick-
ness," these cases being obtained from various sections of the
state. In every case these animals showed the characteristic un-
thrifty appearance.
Fecal examinations were made at frequent intervals on each
case under observation, with the results that very little evidence
of intestinal parasites have been found.
Assuming that the disease was one of nutritional origin, feed-
ing experiments were conducted in an effort to correct the defi-
ciency or other nutritional disturbances. A ration containing
the protein, carbohydrates, and fats in the proportion as they

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Florida Agricultural Experiment Station

Fig. 9.-Typical case of so-called "salt sickness." See Fig. 10

exist in any well balanced ration was given. The concentrates
in the ration were linseed meal, wheat middlings, corn meal,
ground oats, and alfalfa meal, while corn silage and hay consti-
tuted the source of roughage. Each of these animals had access
to a grass pasture, fresh water, and salt at all times.

Fig. 10.-Same animal as in Fig. 9, after being fed a balanced ration
for 65 days.

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Annual Report, 1926

In all five cases, the animals began to show immediate im-
provement after being fed a balanced ration. In two cases the
improvement was very noticeable, due to the immediate rapid
gain in weight. In every case the animal was restored to appar-
ent normal condition by having been fed a balanced ration. In
one case the cow was not making as rapid gain as was desired,
so it was deemed wise to add a mineral mixture to the diet.
This cow apparently made more rapid gains after the mineral
mixture was given as a supplement to the ration. The mineral
mixture used for this purpose consisted of steamed bone meal
and inorganic sources of calcium and phosphorus.
Since there was no evidence of intestinal parasites to such an
extent as could possibly produce the condition, and since all five
cases under observation made a good recovery by simply sup-
plying them with a well balanced ration, it appears that the con-
dition is caused by a nutritional deficiency. However, further
investigational work will be continued on this disease, especi-
ally in regard to the cause and also curative measures which
might be employed to the best advantage.
MANSON'S EYE WORM IN POULTRY
The experimental work on Manson's eye worm was conducted
entirely by Dr. D. A. Sanders. In order to make observations
and conduct experiments to the best advantage, Dr. Sanders was
located in a field laboratory near Manatee. He remained in this
vicinity continuously for a period of six months.
During the year approximately 200 flocks of poultry have
been found to be infested with Manson's eye worm. The degree
of infestation was found to be very variable in these flocks, also
in the infested birds, since some individuals had as few as one
or two while others had as many as 100. The birds which were
infested had, in each case, been reared thru a "rainy season".
Young chicks or pullets hatched in early spring have not been
observed to be infested up to June 30, 1926. No new infesta-
tions had been found up to this date.
Fifteen post-mortem examinations were made in connection
with this investigation, and from these examinations it was
found that mature and also slightly immature worms were lo-
cated in the tear sinus, just beneath the "winking membrane" or
third eyelid. The length of the mature parasite was found to
vary from 14 mm.-18 mm. (approximately %-% inch). Eggs

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Florida Agricultural Experiment Station

and young larvae were found in the digestive tract of infested
birds. No evidence of the parasite could be found in any other
portion of the body.
The life history of Manson's eye worm as thus far determined
is as follows: Sexually mature female worms lay the eggs,
each egg already containing an embryo. These eggs are passed
out into the conjunctival sac of the eye and are immediately
washed down the tear duct which conveys them to the throat,
where they are swallowed. The eggs then pass thru the en-
tire length of the digestive tract. Some of the eggs are hatched
in the intestines, but most are discharged with the feces to the
outside where hatching occurs. The length of time it takes for
the eggs which are discharged with the feces to hatch depends
upon the temperature and moisture conditions. When these con-
ditions are favorable, hatching was found to occur in a few
hours, but under adverse conditions, this process was delayed
for weeks. The newly hatched larvae feed upon the fecal mat-
ter in which they occur.
These larvae are about .2 mm. in length. Microscopical ex-
aminations of the larvae show them actively writhing, darting
about from place to place in snake-like fashion. They have a
very rudimentary oesophagus and are in a very incomplete
stage of development. Further growth takes place very slowly.
A gradual development of the internal organs and a moulting
occurs. When the larvae reach the length of about 1 mm., the
male organs can be seen in their first stages of development.
Dried fecal material which could be pulverized and blown
away has been soaked overnight and found to contain live lar-
vae 1 mm. in length.
Over a period of five months' exposure, it was found impos-
sible to transmit the parasite from infested to non-infested
birds kept on board floors, and also impossible to transmit the
parasite from infested to non-infested birds kept on premises
free from the parasite. For each of these conditions, four in-
fested and four healthy birds were used in the experiment. In
each case, a degree of sanitation as would be given the average
farm poultry flock was maintained. The period of these ex-
posure experiments was from November 20, 1925, to April 20,
1926. Under these conditions the non-infested birds were there-
fore exposed to the active living stage of the parasite, and to
contaminated premises and water. No infestation could be
transmitted to healthy birds in this manner.

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The outcome of these experiments would lead to several in-
ferences such as: (1) the elimination of immature, non-infec-
tive stages of the parasite, (2) the need of a period of incuba-
tion in the soil or water longer than the exposure allowed in
this experiment, (3) the existence of an intermediate host, (4)
that adult parasites are not transmitted directly from one bird
to another.
Eggs containing embryos of the eye worm are not infestive
when placed in the eyes of chickens. This conclusion was drawn
from the following experiment: On December 14, 1925, 12
sexually mature female worms were removed from the eye of a
chicken and placed in normal salt solution. A few hours later
these worms were teased into fine bits by the use of a tenaculum
and forceps, thereby setting free a large number of eggs contain-
ing embryos. These eggs were placed in the eyes of six pullets.
Repeated observations were made, but no evidence of an infesta-
tion could be found. At the end of a five months' period, the birds
were destroyed and upon a detailed post-mortem examination no
eye worms could be detected.
On December 18, 1925, eggs containing embryos were intro-
duced far down the trachea of each of six birds by means of a
10 c. c. pipette. These birds were destroyed five months later
and each was given a post-mortem examination, with the result
that no evidence of eye worm infestation could be found. Neither
egg nor larval forms of the parasite have ever been found in the
bronchial secretions or in the blood of infested or exposed fowls.
It was not possible to infest healthy birds by placing young
larvae, just recently hatched, directly in the eye. The following
experiment was carried out in an effort to determine this fact;
On December 30, 1925, six mature female worms were removed
from the eye of an infested chicken, and placed in distilled water.
A few hours later these worms were teased into bits by use of a
tenaculum and forceps, thereby setting free a large number of
eggs containing embryos. The culture was kept at room temper-
ature and protected from light. Two days later no appreciable
change had occurred in the development of the eggs, but on the
third day a great number of the eggs had hatched. A large num-
ber of these recently hatched larvae were placed in the eye of a
chicken. Repeated observations were made to determine if in-
festation could occur from newly hatched larvae, but no such
infestation developed. The experiment was continued over a
period of five months.

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Samples of soil which were taken from the yards on infested
farms were found to be contaminated with larval stages of the
parasite. When the soil.was obtained from an area near the
watering and feeding places, and the dust wallows, it was found
to be very heavily contaminated with these larvae. Soil which
was taken from an area immediately adjoining the hen house
proved to be more highly contaminated than soil obtained from
any other area in the yards.
The size of the larvae found in the soil varies with the season
of the year. During the month of November the longest larva
found was .3 m.m. in length, while the vast majority of them
were only about .2 m.m. long. During the month of March, the
average length of the larvae in infested soil was a little less than
1.5 m.m.
Since newly hatched larvae, when introduced in the eye, did
not produce infestation, as was shown in an experiment above
mentioned, it was thought that possibly more mature larvae from
the soil would prove infestive. Accordingly, a sample of highly
infested soil was obtained, and the larvae were isolated there-
from by the process of filtration, using fine copper wire screen-
ing as a filter and water to wash the larvae thru the filter. After
the filtering process was completed, the excess of water was
removed by decantation, which leaves the larvae in a high degree
of concentration. This concentrated solution thus obtained con-
taining larvae from 1.0-2.0 m.m. in length was placed in the eyes
of birds, with the result that no evidence of infestation could be
detected up to June 30, 1926. Therefore, it seems to be quite
clearly established that newly hatched larvae .2 m.m. in length
and also mature larvae 1.5 m.m. are not infestive. This would
seem to indicate that the larvae, must attain a length of more
than 1.5 m.m. before they are infestive.
Eggs of the parasite will hatch in the laboratory in water or
clean moist sand, but the larvae will die within a few days unless
supplied with organic matter.
Eggs from sexually mature female eye worms, when placed in
sterile soil which contains an abundant supply of organic matter
(droppings of birds), will, under favorable conditions, hatch
and within two months' time the larvae will attain a length of
1.5 m.m.
In order to determine whether or not the worms change their
location from one eye to the other in the same fowl, the follow-
ing experiment was conducted: On January 17, 1926, a fowl was

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obtained which showed a severe infestation of eye worms. Re-
peated microscopical examinations of excreted material showed
the presence of eggs. Both eyes contained numerous adult para-
sites. All the parasites which could be found in the left eye were
transferred to the right eye, making a total of about 60 parasites
in the right eye. The left eye was then treated with a solution
of creolin in order to kill any parasites which might not have
been removed. On making repeated examinations over a period
of about one month, it was found that no worms passed from the
right eye to the left eye.
Another interesting condition developed during the time this
bird was on the experiment. After the bird had been under ob-
servation for about one month, the right eye suddenly showed a
marked irritation which caused a disturbance of vision, swelling
of the conjunctiva, lacrimation, apparent burning of the eye, a
nasal discharge, and an inflammation of the nictitating or "wink-
ing membrane." This irritation caused the bird to scratch the
eye frequently with the foot, which caused a laceration of the
outer eyelids. The bird was immediately given a thorough clini-
cal examination with the results that no worms whatever were
found in the right eye on this day, while on the preceding day,
just before these symptoms occurred, numerous worms were
present as was determined by a careful examination. The worms
therefore left the eye very suddenly, within 24 hours time, and
the symptoms just mentioned occurred in connection with their
disappearance. A microscopical examination of the fecal mate-
rial passed by this bird during these 24 hours revealed the pres-
ence of hundreds of eggs and a few larvae. The eggs and larvae
were carefully identified by comparing them with eggs obtained
from sexually mature eye worms and larvae hatches from eggs of
sexually mature worms.
The early stages of development of the parasite are passed in
moist soil. Accumulation of infested droppings naturally tends
to increase the number of larvae in the soil; therefore the sani-
tary disposal of such droppings would lessen the number of
larvae, and the spread of the disease would be less general.
Various chemicals have been applied to the soil in an attempt
to destroy the free-living larval forms of Manson's eye worm, but
further observations are necessary before any conclusions can be
reached regarding this phase of the work.
Young larvae buried six inches deep in a tile were alive when
examined one month later.

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Experiments in connection with rotation of runs are being
conducted at the present time.
The best treatment thus far employed for killing the parasite
in the eye consists first of anaesthetizing the eye with a 5 percent
solution of cocaine or a 5 percent solution of Butyn, and then
lifting the nictitating membrane and dropping a 5 percent solu-
tion of creolin directly into the inner corner of the eye immedi-
ately under the nictitating membrane.
Valuable aid has been obtained from the work of Wilcox and
McClelland of the Hawaii Agricultural Experiment Station,
Honolulu, as published -in Press Bulletin No. 43.-1913, "Eye
Worm of Chicken," and also Ransom. U. S. D. A., B. A. I. Bul.
60, "Manson's Eye Worm of Chickens."
"LEECHES" IN HORSES
The disease called "leeches" is very prevalent in some sections
of this state during the summer months, and most especially
during and following the rainy season. This disease affects
horses primarily, tho occasionally cases are found in cattle. The
disease is limited apparently to low, marshy soil, and evidence
seems to prove that horses become infected while grazing over
this type of soil.
There is apparently a variation in the susceptibility of horses
for "leeches", since some horses become infected readily when
allowed to graze over infected areas while others will resist
the infection entirely, even tho they are grazed over the same
pasture and at the same time as did horses which became in-
fected. Another noticeable characteristic of the disease is that
the susceptible horses are subject to infection each time they
are permitted to graze over an infected area during the rainy
season of each year.
In the diseased tissue of animals infected with "leeches",
numerous granular concretions are found. These concretions
vary in size and shape. Some of the concretions are about the
size of a grain of unhulled rice, being somewhat oblong in shape,
while others are from one-half to three-quarters of an inch long,
with processes extending outward in practically all directions,
having the appearance of several grains of unhulied rice joined
together in almost any conceivable manner.
When the granular concretions are soaked in 30 to 40 percent
solution of caustic potash, a filamentous mass of hyphae of a
fungus can be very readily detected. Since this fungus is con-

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Annual Report, 1926

stantly found in the concretions from diseased tissue taken in all
cases examined, it appears to be pathogenic and responsible for
the disease. All efforts to grow the fungus on the ordinary cul-
ture media such as bouillon, nutrient agar, potato, potato agar
and gelatin have failed. The fungus is stained by use of the
ordinary anilin dye preparations; however, fuchsin and gentian
violet give the best results as stains. Thus far it has been impos-
sible to detect spores in connection with the fungus.
In no case could the disease be transmitted directly to animals
under experimental study. For this experiment, three horses,
two cows, and 12 rabbits were used. Granules containing the
fungus were obtained from diseased tissue, and were macerated
thoroly in distilled water. The solution thus obtained was used
as the inoculating material. Injections of this solution contain-
ing the fungus were made deep into the muscle tissue, and no
evidence of infection occurred. Other injections were made sub-
cutaneously, just beneath the skin, and, likewise, no infection
developed. Assuming that possibly infection entered thru a
slight skin abrasion, areas on experimental animals were shaved,
a few drops of the inoculating solution were applied thereon, and
the skin slightly scarified by a needle point. It was found im-
possible to transmit the disease thru skin abrasions in this
manner.
It has been suggested that possibly some form of aquatic ani-
mal life is necessary for the transmission of the fungus.
Further work on the possible isolation, cultivation, and stain-
ing properties of the fungus is being conducted, and also a de-
tailed study of the pathological changes occurring in the tissue
will be made during further investigational work on this disease.

INFECTIOUS MASTITIS OF CATTLE
Work is being carried out in an effort to find some agents of
therapeutic value in the treatment of infectious mastitis of cattle
(infectious inflammation of the udder).

DIAGNOSIS WORK
In addition to the research work carried out on the various
projects above mentioned, this department has also conducted a
diagnostic laboratory for the examination of diseased animal
specimens. During the year, specimens were examined and a
diagnosis rendered as listed below:

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Contagious abortion in cattle, 50 blood samples; fecal
examination, 58; Texas fever, 3; .hog cholera, 7; Kidney
worms, 8; milk for pathogenic bacteria, 8; blackhead in
turkeys, 1.
The following post-mortem examinations have been made on
fowls:
Fowl cholera, 5; intestinal parasites, 10; coccidiosis, 8;
paralysis, 13; botulism, 9; leukemia, 1; white diarrhea, 1;
catarrh of crop, 1; egg bound, 9; sod disease, 2; roup, 8;
chicken pox, 8; bumble foot, 4; crop bound, 1; vent gleet, 11.
Many inquiries regarding disease of livestock have been re-
ceived thru correspondence during the year, and replies have
been made to these inquiries by this department.
A report on the investigation of livestock diseases in the Ever-
glades, made during the summer of 1925, will be found in the
report of the Everglades Experiment Station.

Annual Report, 1926

REPORT OF AGRICULTURAL ECONOMIST
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Agricultural Economics for the fiscal year ending June 30, 1926.
Respectfully,
C. V. NOBLE,
Agricultural Economist.
A Department of Agricultural Economics was made possible
at this station when Congress passed the Purnell bill. This act,
approved February 24, 1925, made an additional appropriation
to each state experiment station of $20,000 for the fiscal year
beginning July 1, 1925, and provided specifically for investiga-
tional work in the fields of agricultural economics, home econom-
ics, and rural sociology.
Actual work in agricultural economics under this fund was
started at this station in November, 1925, under the supervision
of Dr. J. E. Turlington, head of the Department of Agricultural
Economics of the College of Agriculture. The project entered
upon at that time was an economic study by the survey method
of some 300 Irish potato farms in the Hastings area. On Janu-
ary 1, 1926, Bruce McKinley was appointed Assistant Agricul-
tural Economist in the new Department of Agricultural Econom-
ics of the Experiment Station. He immediately took over the
supervision of the field work in the Hastings area. The field
work has been completed and progress has been made in the
tabulation and analysis of the data.
In order to give some idea of the results to be obtained from a
survey of this nature, a preliminary summary is given of some
facts in this intensive Irish potato region. The farm records
cover the fiscal year beginning November 1, 1924; in other
words, the 1925 crop.
The acreage of potatoes is perhaps the best measure of size of
business in this intensive potato producing region. Table XIV
shows that the larger acreages of potatoes usually result in bet-
ter labor incomes to the farm operators. It also shows that the
larger businesses furnish the opportunity for greater losses,
because there is much more at stake in the event of unfavorable
weather, poor management, market slumps, etc. On the aver-
age, however, those farmers who averaged 100.4 acres of pota-
toes made a labor income of $710 as compared with $32 for those
farmers with an average of 9.9 acres of potatoes.

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TABLE XIV.-RELATION OF SIZE OF BUSINESS, MEASURED BY ACRES IN
POTATOES, TO LABOR INCOME* ON 294 IRISH POTATO FARMS IN THE HAST-
INGS AREA.
Average Number Average Range in
Acres in Acres per of Labor Labor
Potatoes Farm Farms Income Incomes

70 and over........ 100.4 42 $710 -$12,276 to $14,818
50 thru 69 .......... 54.9 52 656 8,637 to 8,809
40 thru 49 .......... 41.7 40 223 8,926 to 6,666
30 thru 39 .......... 33.8 57 629 2,723 to 10,303
16 thru 29 .......... 22.7 50 149 6,020 to 6,330
15 and under ...... 9.9 53 32 4,113 to 4,648
Average all
Farms ............ 41.9 294 a$401 -$12,276 to $14,818
*Labor Income is what the farmer received for his year's work above
interest at 7% on his investment and all farm expenses, and in addition to,
having a house to live in and farm products to use in the house.

On April 12, 1926, H. G. Hamilton, who had been an instruc-
tor in the Agricultural Economics Department of the College,
up to this time, was appointed Assistant Agricultural Economist
in the Experiment Station. Arrangements were made for him
to continue a project that he had already started dealing with
the costs of picking, hauling, and packing Florida citrus fruits.
Data from 100 packing houses operated by both marketing asso-
ciations and private organizations have been secured covering
the 1924-1925 crop. Figures from the same concerns will be
obtained for the 1925-1926 crop and the results of the two years
analyzed and compared. This project is the beginning of a more
comprehensive study of the marketing of citrus fruits which is
being planned for the future.
On May 10, 1926, Dr. C. V. Noble assumed his duties as Head
of the Department of Agricultural Economics. A third project
was outlined for a farm management survey of some 500 farms
in a general farming region of Northwest Florida. Jackson
County was selected for the survey and the field work was pro-
gressing nicely at the end of the fiscal year.

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Annual Report, 1926

REPORT OF HOME ECONOMIST
Wilmon Newell, Director.
SIR: I submit the following report of the Home Economics
Department for the fiscal year ending June 30, 1926.
Respectfully,
OUIDA DAVIS ABBOTT,
Home Economist.
On November 1, 1925, the Department of Home Economics
was organized. An experimental kitchen and a biochemical
laboratory were equipped. The work of the department during
the year was devoted to a Vitamine A problem, a nutritional
survey of two representative counties of Florida, the determina-
tion of the spoilage of canned non-acid vegetables, and to some
of the factors that affect the jellying properties of several of the
less known fruits of Florida.

VITAMIN A
Vitamine A, the vitamin that promotes growth and prevents
xerophthalmia, is formed only in green plants. Inasmuch as the
vitamin has never been isolated and it is not known how it is
formed by the plants, a study of some of the factors that may
affect its formation in alfalfa plants have been considered. Al-
falfa was selected because of its high Vitamine A content and
its adaptability to water cultures.
In the study of the factors that influence the formation of Vita-
mine A in alfalfa plants, the Home Economist has had the cooper-
ation and assistance of the Soil Chemist, Dr. R. M. Barnette, who
has grown the plants used in the experiment.
Because of the intimate association of growth with Vitamine
A, and of growth with light, the first factors that have been con-
sidered have been the intensity and the time of illumination on
the formation of Vitamine A in alfalfa seedlings. Part of the
plants were grown in light and others in the dark. The plants
were then dried and fed to albino rats that were on a Vitamine A
free diet prepared according to the methods of Sherman. The
results indicate that light may be in some way associated with
the formation of Vitamine A in alfalfa seedlings.
The experimental animals are kept in a house that has been
especially built for that purpose. The house and equipment pro-
vide adequate light, ventilation and sanitation.

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In so far as environmental factors seem to influence the for-
mation of Vitamine A in plants to some extent, it was believed
that a study of other environmental factors might assist in the
explanation of some nutritional disorders found in children of
sections where the soils are relatively poor in certain elements.
The effect of the lack or the addition of certain elements on the
formation of Vitamine A in alfalfa is now being considered.

NUTRITIONAL SURVEY

A survey to determine the nutritional status of children be-
tween the ages of six and twelve years in five representative coun-
ties of Florida was begun by Miss Georgia Westover, who was
assistant in the Department until the end of the fiscal year. With
the help of the County Health Doctor and the Red Cross Nurse,
Miss Westover examined 500 rural children of two counties,
working thru the public schools. The results of this examina-
tion show that 50 percent of the children examined are from 5
to 33 percent under weight; 48 percent have defective teeth, and
33 percent have enlarged tonsils. Further examination has
shown the prevalence of conjunctivitis, skin eruptions, and
anemia. The presence of hookworm has complicated this prob-
lem and it will be necessary to run the basal metabolism of a
number of children that have hookworm in order to determine
the effect of hookworm on nutrition. Basal metabolism studies
will make it necessary to buy a calorimeter and other equipment.
A record of the food eaten by the child for a definite period of
time has been secured from the families in order to determine
if there, be a. correlation between the food used in the family
and the nutritional status of the child. The work is now being
extended into other counties.

SOME FACTORS THAT INFLUENCE JELLYING

In an attempt to find some satisfactory way of using certain
of the less known fruits of Florida, preliminary experiments
were run to determine if a standard jelly could be made from
kumquats. These experiments show that the kumquat has 1.688
percent pectin and the hydrogen ion concentration is pH2.9. Ac-
cording to standards that have been set up for jellies, kumquats
should make an excellent jelly. It has been found, however, that
kumquats, like other citrus fruits, do not make a standard jelly.

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There are indications that the predominant acid and the salt
content as well as the H-ions concentration may 6xert consid-
erable effect on the jellying properties of these fruits. A new
method of purifying pectin is being used that makes it possible
to prepare a relatively salt-free pectin. By the use of this pectin
the effect of salts and various acids on the character of the gel
can be determined, and it is quite possible that with this informa-
tion a first class jelly can be prepared from citrus fruits. The
preparation of this pectin involves the use of special apparatus,
as an ultra-condenser, potentiometer, and dializer.

CANNING OF NON-ACID VEGETABLES
In Florida the preservation of non-acid vegetables is very
difficult. In trying to determine the causes of spoilage, two
methods of canning have been followed:
No. 1-Hot pack-3 hrs. in a water bath.
No. 2-Hot pack-10 lbs. pressure for 50 minutes.
Peas have not kept by either method. At present corn has
kept by both methods. This is perhaps due to the methods of
packing the jars. The corn was packed loosely into the jars and
the jars filled with hot water. By packing in this way the heat
penetrates quickly to the center of the jars while if the corn
is packed tightly into the jars the temperature in the center of
the jar may never be high enough to kill the spores. Isolations
are being made in an effort to find the specific organism that is
causing the spoilage of peas. Other non-acid vegetables are now
being canned.

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Florida Agricultural Experiment Station

REPORT OF THE CITRUS EXPERIMENT STATION
Wilmon Newell, Director.
SIR: I submit the following report of the Citrus Experiment
Station, at Lake Alfred, for the fiscal year ending June 30, 1926.
Respectfully,
JOHN H. JEFFERIES,
Superintendent.

The work of the Citrus Experiment Station has been carried
forward during the past year in connection with the projects re-
ported below. All of the Station's land suited to citrus has now
been planted and includes about 63 acres.
The buildings, fences, and equipment are in good condition and
the Station has a full line of necessary tools, such as plows, har-
rows, dusters, mowers, etc. 'for carrying on its field work. A
modern greenhouse to cost $5,000 was contracted for early in the
spring of 1926 and will be ready for use in the near future.

THE BUD SUPPLY PROGENY GROVE
This grove has made a remarkable growth. It contains all
of the present day commercial varieties of citrus and has a
very good crop of fruit. The quality of the fruit of most varie-
ties is splendid, especially of the pineapple. All the strains are
of the best that could be found in the State. The bud selection
was made by T. Ralph Robinson of the U. S. Department of
Agriculture and the work is in cooperation with the Department.

VARIETY GROVE

This grove includes 20 varieties of citrus that are budded on
three different rootstocks, rough lemon, sour orange, and grape-
fruit. Where the soil and the location are congenial to grape-
fruit stock, trees on them have made growth equal to that of
trees on the rough lemon, and the quality of the fruit is better.
The trees budded on grapefruit stock are later coming into bear-
ing and are not so prolific. The trees on sour orange stock have
about half as much bearing surface of those on rough lemon,
but the quality of the fruit is excellent. All of these trees have
had the same fertilizer and cultivation.

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