• TABLE OF CONTENTS
HIDE
 Front Cover
 Title Page
 Letter of transmittal
 Credits
 Frontispiece
 Main
 Index














Group Title: Annual report, University of Florida. Agricultural Experiment Station.
Title: Annual report for the fiscal year ending June 30th ...
ALL VOLUMES CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00027385/00020
 Material Information
Title: Annual report for the fiscal year ending June 30th ...
Series Title: Annual report for the fiscal year ending June 30th.
Alternate Title: Florida Agricultural Experiment Stations annual report
Physical Description: 23 v. : ill. ; 23 cm.
Language: English
Creator: University of Florida -- Agricultural Experiment Station
Publisher: The Station
Place of Publication: Gainesville Fla
Publication Date: 1934
Frequency: annual
regular
 Subjects
Subject: Agriculture -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
 Notes
Statement of Responsibility: University of Florida, Gainesville, Florida, Agricultural Experiment Stations.
Dates or Sequential Designation: 1931-1967.
 Record Information
Bibliographic ID: UF00027385
Volume ID: VID00020
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: ltuf - AMF8114
oclc - 12029671
alephbibnum - 002452809
lccn - sf 91090332
 Related Items
Preceded by: Report for the fiscal year ending June 30th ...
Succeeded by: Annual research report of the Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida

Table of Contents
    Front Cover
        Front Cover 1
        Front Cover 2
    Title Page
        Page 1
    Letter of transmittal
        Page 2
    Credits
        Page 3
    Frontispiece
        Page 4
    Main
        Page 5
        Page 6
        Page 7
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    Index
        Page i
        Page ii
        Page iii
        Page iv
        Page v
        Page vi
        Page vii
        Page viii
        Page ix
Full Text










UNIVERSITY OF FLORIDA
GAINESVILLE, FLORIDA



AGRICULTURAL EXPERIMENT

STATION





Annual Report
FOR THE FISCAL YEAR ENDING
June 30, 1934











LIST OF DEPARTMENT REPORTS
Page
R report of the D irector.............................................................. ....................................................... 5
Report of Business Manager........................................... .. .. ........ .. ............ . 12
Publications, News, Radio......................... ............. .......................... ......................... 17
The Library ................................ .......... .................... ... .................... ..... ........ 21
Agricultural Economics................. -....... --....... .............. ... ...................... ...... .. 22
Agronom y....................................................................................... ................................... .. 25
Animal Husbandry ............................................... .... .. .. ... ............--- --- 85
Chemistry and Soils-................................. ...... .... ..................... .......... ....... 47
Entom ology.......... ................................ ..... ......... ... ........ ..- .. ..-..... ............ 51
Home Economics-........................--....... ........ ..-... ......... .. ............... 57
H orticulture................................................................... ................... ............... ............ 61
Plant Pathology.................................... .. --- ............. ...... ...------ 70
Citrus Experiment Station..................................................... ...---- ....-- .......-............. 81
Everglades Experiment Station.............................................. ..... ... .................. 86
North Florida Experiment Station...... ......... ...................................... ......................................... 113
Sub-Tropical Experiment Station.....................................-..... ............. ........... 122
W est Central Florida Experiment Station.................................. ....... ............... .............. 130








Hon. Dave Sholtz,
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 Experiment Stations
for the fiscal year ending June 30, 1934.
Respectfully,
GEORGE H. BALDWIN,
Chairman, Board of Control.







Hon. George H. Baldwin,
Chairman, Board of Control.

SIR: I have the honor to transmit herewith the annual report of the
Director of the University of Florida Agricultural Experiment Stations
for the fiscal year ending June 30, 1934, and I request that you transmit
the same, in accordance with law, to His Excellency, the Governor of
Florida.
Respectfully,
JOHN J. TIGERT,
President, University of Florida.









EXECUTIVE STAFF

John J. Tigert, M.A., LL.D., President of the
University
Wilmon Newell, D.Sc., Director
H. Harold Hume, M.S., Asst. Dir., Research
Harold Mowry, M.S.A., Asst. Dir., Adm.
J. Francis Cooper, M.S.A., Editor
R. M. Fulghum, B.S.A., Assistant Editor
Jefferson Thomas, Assistant Editor
Ida Keeling Cresap, Librarian
Ruby Newhall, Administrative Manager
K. H. Graham, Business Manager
Rachel McQuarrie, Accountant


MAIN STATION, GAINESVILLE

AGRONOMY
W. E. Stokes, M.S., Agronomist**
W. A. Leukel, Ph.D., Agronomist
G. E. Ritchey, M.S.A.. Associate*
Fred H. Hull, M.S., Associate
W. A. Carver, Ph.D., Associate
John P. Camp, M.S., Assistant

ANIMAL HUSBANDRY
A. L. Shealy, D.V.M., Animal Husbandman**
R. B. Becker, Ph.D., Dairy Husbandman
W. M. Neal, Ph.D., Associate in Animal
Nutrition
D. A. Sanders, D.V.M., Veterinarian
M. W. Emmel, D.V.M., Asst. Veterinarian
W. W. Henley, B.S.A., Asst. Animal Hus-
bandman
P. T. Dix Arnold, B.S.A., Assistant Dairy
Husbandman

CHEMISTRY AND SOILS
R. W. Ruprecht, Ph.D., Chemist**
R. M. Barnette, Ph.D., Chemist
C. E. Bell, Ph.D., Associate
H. W. Winsor, B.S.A., Assistant
H. W. Jones, M.S., Assistant

ECONOMICS, AGRICULTURAL
C. V. Noble, Ph.D., Agricultural Economist**
Bruce McKinley, A.B., B.S.A., Associate
Zach Savage, M.S.A., Assistant

ECONOMICS, HOME
Ouida Davis Abbott, Ph.D., Specialist**
L. W. Gaddum, Ph.D., Biochemist
C. F. Ahmann, Ph.D., Physiologist

ENTOMOLOGY
J. R. Watson, A.M., Entomologist**
A. N. Tissot, Ph.D., Associate
H. E. Bratley, M.S.A., Assistant

HORTICULTURE
A. F. Camp, Ph.D., Horticulturist**
G. H. Blackmon, M.S.A., Horticulturist
A. L. Stahl, Ph.D., Associate
R. J. Wilmot, M.S.A., Specialist, Fumigation
Research
R. D. Dickey, B.S.A., Assistant Horticulturist

PLANT PATHOLOGY
W. B. Tisdale, Ph.D., Plant Pathologist**
George F. Weber, Ph.D., Plant Pathologist
R. K. Voorhees, M.S., Assistant
Erdman West, M.S., Mycologist

In cooperation with U.S.D.A.
** Head of Department.


BOARD OF CONTROL

Geo. H. Baldwin, Chairman, Jacksonville
A. H. Blanding, Bartow
A. H. Wagg, West Palm Beach
Oliver J. Semmes, Pensacola
Harry C. Duncan, Tavares
J. T. Diamond, Secretary, Tallahassee

BRANCH STATIONS

NORTH FLORIDA STATION, QUINCY
L. O. Gratz, Ph.D., Plant Pathologist in
Charge
R. R. Kincaid, Ph.D., Asso. Plant Pathologist
J. D. Warner, M.S., Agronomist
R. M. Crown, B.S.A., Asst. Agronomist
Jesse Reeves, Farm Superintendent

CITRUS STATION, LAKE ALFRED
John H. Jefferies, Superintendent
Geo. D. Ruehle, Ph.D., Associate Plant
Pathologist
W. A. Kuntz, A.M., Assoc. Plant Pathologist
B. R. Fudge, Ph.D., Associate Chemist
W. L. Thompson, B.S., Asst. Entomologist
EVERGLADES STATION, BELLE GLADE
A. Daane, Ph.D., Agronomist in Charge
R. N. Lobdell, M.S., Entomologist
F. D. Stevens, B.S., Sugarcane Agronomist
G. R. Townsend, Ph.D., Asst. Plant Patholo-
gist
B. A. Bourne, Ph.D., Sugarcane Physiologist
J. R. Neller, Ph.D., Biochemist
R. W. Kidder, B.S., Asst. Animal Husband-
man
Ross E. Robertson, B.S., Assistant Chemist
SUB-TROPICAL STATION, HOMESTEAD
H. S. Wolfe, Ph.D., Horticulturist in Charge
W. M. Fifield, M.S., Asst. Horticulturist
Stacy O. Hawkins, M.A., Assistant Plant
Pathologist
WEST CENTRAL FLORIDA STATION,
BROOKSVILLE
W. F. Ward, M.S.A., Asst. Animal Husband-
man in Charge*

FIELD STATIONS

Leesburg
M. N. Walker, Ph.D., Plant Pathologist in
Charge
W. B. Shippy, Ph.D., Asso. Plant Pathologist
K. W. Loucks, M.S., Asst. Plant Pathologist
J. W. Wilson, Ph.D., Associate Entomologist
C. C. Goff, M.S., Assistant Entomologist
Plant City
A. N. Brooks, Ph.D., Plant Pathologist
R. E. Nolen, M.S.A., Asst. Plant Pathologist
Cocoa
A. S. Rhoads, Ph.D., Plant Pathologist
Hastings
A. H. Eddins, Ph.D., Plant Pathologist
Monticello
------, Assistant Entomologist
Bradenton
David G. Kelbert, Asst. Plant Pathologist
Sanford
E. R. Purvis, Ph.D., Assistant Chemist,
Celery Investigations






































Lii
.1;.k


Fig. 1.-A "before and after" view of the Everglades Experiment Sta-
tion grounds. The upper vie* was taken July 13, 1929, while the lower
picture was taken from the same position (the top of the barn) August 20,
19,4.










Report for the Fiscal Year Ending

June 30, 1934





Dr. John J. Tigert,
President, University of Florida.
SiR: I have the honor to transmit herewith my report on the work and
investigations of the University of Florida Agricultural Experiment Sta-
tions, together with the reports of the heads of the several departments,
for the fiscal year ending June 30, 1934.
Respectfully,
WILMON NEWELL,
Director.






INTRODUCTION
The work and findings of the several departments of the Agricultural
Experiment Station, which include the main station, branch stations and
field laboratories, are summarized on the following pages.
Research in the agricultural field has been continued under eight major
divisions: Agronomy, Agricultural Economics, Animal Husbandry, Chem-
istry and Soils, Entomology, Home Economics, Horticulture and Plant
Pathology. Branch stations and field laboratories have been maintained
as follows:
Citrus Station, Lake Alfred
Everglades Station, Belle Glade
North Florida Station, Quincy
Subtropical Station, Homestead
Tomato Disease Laboratory, Bradenton
Potato Disease Laboratory, Hastings
Strawberry Disease Laboratory, Plant City
Watermelon Laboratory, Leesburg
Citrus Disease Laboratory, Cocoa
Pecan Insect Laboratory, Monticello
Celery Investigations Laboratory, Sanford
The laboratory for the study of anaplasmosis of cattle in West Palm
Beach was discontinued with the solution of the major research problem
for which it was established and, in accordance with legislative enactment,
a field laboratory for the investigation of nutritional troubles of celery
was opened at Sanford.
Cooperative projects in agronomy and animal husbandry have been
continued with the U. S. Department of Agriculture at the federal West
Central Florida Experiment Station, Brooksville.







Florida Agricultural Experiment Station


FINANCIAL RESOURCES
The financial resources of the Experiment Stations for the fiscal year
ending June 30, 1934, including balances carried forward from the previous
year, were as follows:
Federal Adams Fund.................-.............................................................. $ 15,000.00
Federal Hatch Fund................................................................................ 15,000.00
State Funds
M ain Station .......................................................... .......................... 201,755.50
Including Field Laboratories as follows:
Tomato Disease Investigations, Bradenton........$2,900.00
Strawberry Investigations, Plant City................ 6,300.00
Citrus Disease Investigations, Cocoa.................... 3,500.00
Potato Disease Investigations, Hastings............ 5,250.00
Pecan Insect Investigations, Monticello.............. 1,750.00
Celery Investigations, Sanford.............................. 5,250.00
Fumigation Research .............................................. 3,062.50
Grape Pest Investigations...................................... 3,500.00
Citrus Experiment Station, Lake Alfred........................................ 11,451.00
Everglades Experiment Station, Belle Glade................................ 50,339.00
North Florida Experiment Station, Quincy.................................. 20,968.00
Subtropical Experiment Station, Homestead.................................. 10,579.00
Watermelon Investigations Laboratory, Leesburg........................ 6,229.00
Incidental Funds, Sales, etc............................................................. 10,535.95
$341,857.45
Federal Funds, not included above.................................................. 60,000.00
CHANGES IN STAFF
The following changes took place in the Station staff during the fiscal
year ending June 30, 1934:
Ralph D. Dickey was appointed Assistant Horticulturist, July 15, 1933.
E. R. Purvis was appointed Assistant Chemist, Celery Investigations,
October 1, 1933.
M. W. Emmel was appointed Assistant Veterinarian, October 1, 1933.
Zach Savage was appointed Assistant Agricultural Economist, October
1, 1933.
Fred W. Walker, Assistant Entomologist, died October 9, 1933.
R. V. Allison, Soils Specialist in Charge, Everglades Station, was granted
one year's leave of absence, effective November 9, 1933, to assume charge
of soil erosion investigations with the United States Department of Agri-
culture.
Fred H. Hull was granted leave of absence from January 20, 1934 to
March 20, 1934 to pursue graduate studies at Iowa State College.
C. F. Ahmann was granted leave of absence February 3, 1934, for one
year to pursue graduate studies at the Tennessee School of Medicine.
J. M. Coleman, Assistant Chemist, died February 18, 1934.
M. R. Ensign, Associate Horticulturist, resigned March 31, 1934.
Marvin A. Brooker, Associate Agricultural Economist, resigned April
30, 1934.
SCOPE OF THE STATION'S WORK
July 1, 1933-June 30, 1934
The major research projects of the Agricultural Experiment Stations
are listed below, arranged according to departmental classification and with
page reference to a discussion of the work of each project.




Department
AGRICULTURAL
ECONOMICS





AGRONOMY















ANIMAL
HUSBANDRY


Number
73

154
186
197
235

248
20
27
55
56
98
100
105
106
107
120
153

159
163
174
177
243

119
133
136
137
140

149
160
175
178
179
188
192
194
213


Title Page
Agricultural Survey of Some 500 Farms in the General Farming Region of
N orthw est F lorida .......................................................................................................... 22
Farmers' Cooperative Associations in Florida ................................................................. 22
Cost of Production and Grove Organization Studies of Florida Citrus...................... 22
Cost of Handling Citrus Fruit from the Tree to the Car....................................... 23
A Study of Pre-Cooling and of Refrigeration in Transit as Affecting Cost of
Marketing, Quality and Price of Citrus Fruits...................................... ........... 24
F arm T taxation ........................................................................................................................ 24
Plant Breeding-- Peanuts ...................................................................................................... 25
Pasture E xperim ents ................................................ ............................... ....................... 26
Crop Rotation Studies with Corn, Cotton, Crotalaria and Austrian Peas.................... 27
Variety Test W ork with Field Crops ............................................................................... 27
Green M anure Studies .......................... .................................................... ..................... 29
Growth Behavior of Pasture Grasses ................................................. ....................... 29
Improvement of Corn Through Selection and Breeding.................................................. 29
Effect of Time of Planting of Corn on Forage and Grain Yield................................ 30
Crop A adaptation Studies........................................................................................................ 30
Fertilization of Pasture and Forage Grasses................................................................ 30
Date of Seeding and Phosphate Requirements of Winter Legumes and Their Effect
Upon Subsequent Crops..---.. -----............ ........................ 31
Ratio of Organic to Inorganic Nitrogen in Mixed Fertilizer for Cotton........................ 31
Corn Fertilizer Experim ents............................................................... ........................ ..... 31
A Study of Crotalaria as a Forage Crop.................................. ... .............................. 33
A Study of Crotalaria as a Forage Crop for Rabbits................................................. 33
A Study of the Development and Deterioration of Roots in Relation to the Growth
of Pasture Plants Grown Under Different Fertilizer and Cutting Treatments 33
The Etiology of Neurolymphomatosis gallinarum (Fowl Paralysis)............................ 37
Deficiencies in Feeds Used in Cattle Rations --.................-- ......-...- .............. ............ 37
Comparison of Grazing Crops with Dry Lot Feeding for Pork Production............ 38, 117
The Value of Grazing for Fattening Cattle in Beef Production............ .............. 39
Relation of Conformation and Anatomy of the Dairy Cow to Her Milk and Butter
Fat Production ........... .... ................................. ........... 39
A naplasm osis in Cattle........................................................................................................... 39
Fattening Fall Pigs for Spring Market-... --------...................... .--------........................... -39
A Study of Feeding Value of Crotalarias---....................---........--... ---.......... ...................... 40
Comparison of Poultry Vermifuges for Efficacy and Effect on Egg Production........ 40
Swine Field Experiment..-- ------------..... ......... .----- ----------. .. 40
The Determination of Digestibility Coefficients for Crotalaria Hay............................ 40
The Effect of Feeding Crotalaria Seed to Chickens and Other Birds............................ 41
Improving the Size and Quality of Native Cattle by the Use of Purebred Bulls........ 41
A Study of the Ensilability of Florida Forage Crops.................................................... 41







Department
ANIMAL
HUSBANDRY
(Continued)




















CHEMISTRY
AND SOILS


Number
215
216
217
218
219
224
225
226
227
228

229
236
239
241

244

245

246
250

251
257
21
22
36
37
67
94
95
96
141
166
220
223
240
252


Title Page
Beef Cattle Breeding Investigations------------... ..--...-....-.---. ------- 42
Cooperative Field Studies with Beef and Dual Purpose Cattle---.........................------- 42
Dual Purpose Cattle Investigation under Farm Conditions----..~..--. ..--- ......-..---- 42
Factors Affecting the Percentage of Calf Crop and Size of Calves.......................----.. .. 42
Beef and Dual Purpose Cattle Investigations....------ .................................. 43, 110
Use of Peanuts and Peanut Products in Rearing Turkeys............... ----............ 130
Confinement Versus Range Rearing of Chicks-.....-----... ---- ---------.... 131
Importance of Range Rotation in Poultry Production....................... ------ 131
A Study of Egg Production and Mortality from Pullets Reared Under Confinement
Versus Range Conditions-....----------. .....------------------ 132
A Comparative Study of the Value of Milk Solids, Peanut Meal, Meat Meal and
Fish Meal in Fattening Broilers and Fryers...................-......... -- ............... 132
All Night Lights Versus No Lights on S. C. White Leghorn Pullets-........................... 132
Investigations of Hemorrhagic Septicemia in Cattle and Swine..........------------- .43
The Digestibility Coefficients and Feeding Value of Dried Grapefruit Refuse-........ 43
Efficiency of the Trench Silo for Preservation of Forage Crops, as Measured by
Chemical Means and by Utilization of Nutrients of Silage by Cattle---................. 44
A Comparative Study of Corn, and Liquid Milk, vs. a Grain and Mash Ration
in Feeding for Egg Production.... ---------------------------. 44
A Comparative Study of the Value of Meat Scraps, Fish Meal and Milk Solids as
Sources of Protein for Egg Production ..........------ ...----------- 45
Lights vs. No Lights for Egg Production -.. ......---------.. ------ ----- 45
The Effect of Feeding Colon Organisms and Dried Whey on the Bacterial Flora
of Baby Chicks Affected with Pullorum Disease............................. .. 45
The Etiology of Leukemia in the Domestic Fowl.. ---------------.................................................... 46
Columbia Sheep Performance Investigation .. ----------------.--..... 46
Dieback of Citrus............................ ......... ...........--------------------........... 47, 81
Effect of Varying Amounts of Potash on Composition and Yield and Quality of Crop 47,82
Determination of the Fertilizer Requirements of Satsuma Oranges------......--.................--. 47
Effect of Various Potash Carriers on Growth, Yield and Composition of Crops........ 47
Composition of Crops as Influenced by Fertilization and Soil Types-Pecans.......... 47
Effect of Various Fertilizer Formulas.--..--- ---.........-----....................~-......--- 48
Concentrated Fertilizer Studies.... ....................... ............ .............. ... ......... 48
Determination of the Effect of Green Manures on Composition of Soil ----....... ...... 48
Effect of Fertilizers and Soils on Composition of Truck Crops..........................--........ 49
Decomposition of Forest, Range and Pasture Growths to Form Soil Organic Matter 49
A Study of "Chlorosis" in Corn Plants and Other Field Crop Plants........................ 49
Bronzing or Copper Leaf of Citrus-..-----.................. ......... ... ...... ............ 50
The Occurrence and Behavior of Less Abundant Elements in Soils...........................- 50
Soil and Fertilizer Studies with Celery ............................------ ---- --------....... .................... ... 50




Department
ENTOMOLOGY













HOME ECONOMICS










HORTICULTURE


Number
8
12
13
14
28
60
82
157
162
214
230
231
232
233
234
142

198
199

201

221
222

255
256
46
47
48
50
52
80
110
111
139
165

187


Title Page
The Florida Flower Thrips (Frankliniella cephalica bispinosa Morgan) .................. 51
Root K not Investigations............. ...... .... ... .............. .. ............................... .. 51
Introduction and Propagation of Beneficial Insects........................................................ 52
The Larger Plant Bugs.................. ........................ .. .... ............. .. ........ .. 52
Bean Jassid Investigations................................ .......... ........... ...... .... ............. 53
The Green Citrus Aphid......... ..................... ............. ...... ........ ..... ... 54
Control of Fruit and Nut Crop Insects-Insects Affecting Pecan Trees .............. 54
Control of Scale Insects on Woody Ornamentals--................... ....................... 54
Insect and Other Animal Pests of Watermelons-.................--...........--.. .--- ......... 54
Biology and Control of Field Mice in Watermelon Plantings .......-......... -......... ... 54
The Asparagus Caterpillar (Laphygma exigua) ....................................... .............. 55
The Onion Thrips (Thrips tabaci Lindm )..................................................... ....... ....... 55
The Gladiolus Thrips (Taeniothrips gladioli M. & S.) ......................... .................... 55
Control of Purple Scale and Whiteflies with Lime Sulphur.................. ............. 55
Biology and Control of Florida Aphids-.......................--- ...-.--.... .-----------... 56
The Relation of Growth to Phosphorus, Calcium and Lipin Metabolism as Influenced
by the Thym us..................................................................................-- - 57
A Study of Lecithin Synthesis in Hens on a Vitamin A and Lipoid Free Diet........... 57
A Study of the Changes Which Occur in the Hematopoietic Tissues of Rats on a
Vitamin A Free Diet-.......--. ...-- ..------------................-........----. ...--- ......---... 58
A Study of the Chemical Composition of the Ash of Florida Fruits and Vegetables
wiLh Reference to the More Unusual Constituents....................................... 58
A Study of the Chemical Properties of the Glucosides of Citrus Fruits-.................. 58
A Study of the Pathologic Changes in Tissues and Organs of Animals Affected by
Deficiency Diseases or by Toxic Substances------... -----.............................. 58
An Investigation of Human Dietary Deficiency in Alachua County, Florida............ 58
The Development of Quantitative Spectrographic Methods in Agricultural Research 59
Variety Response of Pecans to Different Soil Types, Localities, etc..----............--............ 61
Cooperative Fertilizer Tests in Pecan Orchards............-- ..............--......----...... ............... 62
Variety and Stock Tests of Pecan and Walnut Trees............-................... ... .---- 62
Propagation, Planting and Fertilizing Tests with Tung-Oil Tree................................ 62
Testing of Native and Introduced Shrubs and Ornamentals ----................... .......... 63
Cooperative Cover Crop Tests in Pecan Orchards...................-------............. 64
Phenological Studies on Truck Crops in Florida-........................... ------------ 64
Fundamental Physiology of Fruit Production---- --...... ....... ............... .. 64
Avocado Maturity Studies........-......-.....-....................-- --.......---...... 65
The Relation of Nitrogen Absorption and Storage to Growth and Reproduction in
Citrus and Pecans.........-...............----... -----..........---..--------........ .......-- 65
Variety Tests of Minor Fruits and Ornamentals..............................--......--..... 65








Department Number
HORTICULTURE 189
(Continued) 190
237
238
PLANT PATHOLOGY 3
19
24
116
126

130
143
145
146
147
148
150
151
167
180
181
182
184
185
193
196
242
247
253
254
CITRUS 26
EXPERIMENT 34
STATION 35
83
102
84


Title Page
Study on the Preservation of Citrus Juices and Pulps-......................................--......... 66
Cold Storage Studies on Citrus Fruits..--......-..-..---......--. -----------...........-- .......-----. 66
Maturity Studies on Citrus Fruits-..-.....------..............................................-- ....... ... 67
Studies on the Effect of Zinc and Other Unusual Mineral Supplements...................... 67
M elanose and Stem-End Rot of Citrus................................................................................ 81
The Downy M ildew of Cucurbits.......................................................................................... 71
Citrus Scab ............................................................................................................................... 82
Nailhead Rust of Tomatoes .. -------......................... ....................................... .... .. 71
Investigations Relative to Certain Diseases of Strawberries of Importance to
Florida ............................. .............. .. .... ......... ...............-- 71
Studies Relative to Disease Control of White (Irish) Potatoes.................................... 72
Investigation of and Control of Brown Rot of Potatoes and Closely Related Plants
Caused by Bacterium solanacearum............................................................................ 72
Investigation and Control of a Disease of Corn Caused by Physoderma Zeae-Maydis 73
Seedling, Stalk and Ear Rot Diseases of Corn Caused by Diplodia spp....................... 73
Seedling, Stalk and Ear Rot Diseases of Corn Caused by Fusarium spp..................... 74
Investigation of Diseases of Ferns and Ornamental Plants............................................ 74
Investigation of and Control of Fusarium Wilt, a Fungous Disease of Watermelons 74
Investigation of and Control of Fungous Diseases of Watermelons........................... 75
A Study of the So-Called "Rust" of Asparagus plumosus............................................... 75
Control of Wilt of Tomatoes (Fusarium lycopersici Sacc.) in Florida........................ 75
Clitocybe Mushroom Root Rot of Citrus Trees and Other Woody Plants in Florida 76
Control of Blackrot of Tomatoes in Florida and in Transit................................. ..... 76
A Study of Strawberry Wilt or Crown Rot-...........-- --...................---...................... 77
Investigations of Stem-End Rot of Citrus Caused by Phomopsis citri Fawcett.......... 84
Certain Studies of Decays of Citrus Fruits in Storage........................--...... .----.... 77
A Study of the Spraying Requirements Necessary to Control Grape Diseases.......... 78
Investigations of a Bark Disease of Tahiti Lime Trees...-------.............. .................. 78
A Study of Sclerotium rolfsii in Florida, Its Host Relations, and Factors Influ-
encing Its Growth and Pathogenicity-........ --.. ------...........--........................... 79
A Study of Rose Diseases in Florida and Their Control..........................--........... 79
Investigations of Fruit Rots of Grapes.................... ................................................. 80
Citrus Progeny and Bud Selection-........................... ........ .... .................:........... 82
Propagation Experiments with Citrus Plants of Various Kinds................................... 83
Testing of Introduced and New Varieties and Hybrids of Citrus and Near-Citrus.... 83
Cover Crop and Green Manure Studies in Citrus Groves---...................------........- -- 83
Citrus Variety Tests. Including Root Stocks................................................................ 84
Forage, Truck and Field Crop Trials.............................................. ........................ 89




Department
EVERGLADES
EXPERIMENT
STATION
























NORTH FLORIDA
EXPERIMENT
STATION


Number
85
86
87

88
89
90
168

169
170
171
172
173
195
202
203
204
205
206
207
208
209
210
211

212

249
25
33
101
191

200


SUB-TROPICAL
EXPERIMENT STATION
WEST CENTRAL
FLORIDA STATION


Title P
Fruit and Forest Tree Trials and Other Introductory Plantings .........................
Soil Fertility Investigations Under Field and Greenhouse Conditions..................
Field and Laboratory Studies Upon Insect Pests of South Florida with Particular
Reference to M ethods of Control.................................................... ........................
Soils Investigations ................................................................................................................
W after Control Investigations..................................................................
Studies in Crop R otation................................. .........................................................
Studies Upon the Role of Special Elements in Plant Development Upon the Peat
and Muck Soils of the Everglades....................................
Studies Upon the Prevalence and Control of the Sugar Cane Moth Borer................
Prevalence and Control of Rodents Under Field and Village Conditions....................
Cane Breeding Experiments............................. ................. .........................................
General Physiological Phases of Sugar Cane Investigations......................-..........
Agronomic Phases of Sugar Cane Investigations............................
Pasture Investigations on the Peat and Muck Soils of the Everglades..................
Agronomic Studies with Sugar Cane..................................................................................
Forage Crops Investigations.......................................... ..................................................
Grain Crop Investigations......... ...................... ....................................... ..................... .....
Seed Storage Investigations.................................................................................
Fiber Crops Investigations.......... ................. ................... ......................
Cover Crop Investigations..................................... ....................... .........
Agronomic Studies Upon the Growth of Syrup and Forage Canes in Florida............
The Seed and Soil Borne Diseases of Vegetable Crops....................................................
The Leaf Blights of Vegetable Crops................................................... ....................
Study Upon Various Physiological Phases of Plant Nutrition with Particular
Reference to Those Finding Important Relations to Crop Production in the
Everglades.................................................................. ......................-----
Chemical Studies Upon Relation of Organic Composition of Agricultural Plants to
Progress of Vegetative Development and Occurrence of Maturity........................
Nematode Investigations .......................-------- .......- ................................
Field and Laboratory Studies of Tobacco Diseases........................................................
Developing Strains of Cigar Wrapper Tobacco Resistant to Black Shank....................
Genetics of Cotton: Studies in Inheritance of Cotton....................................................
Some Factors Affecting the Germination of Florida Shade Tobacco Seed and Early
Growth of the Seedlings .................................. ....... ........... ..............................
Cotton Nutrition Studies.. ........ ............................... .......................

No Numbered Projects. Progress Report on page.............-......-.............----


'age
89
91

93
94
94
95

96
96
97
97
100
101
101
102
103
104
105
105
106
106
106
107

108

109
111
116
116
117

117
118

122 i
i-


No Numbered Projects. Progress Report on page--------------................................... 130







12 Florida Agricultural Experiment Station

REPORT OF BUSINESS MANAGER
Receipts and expenditures of state funds of the Main Experiment Station,
Branch Experiment Stations and Field Laboratories for the fiscal year
ending June 30, 1934, were as follows:
MAIN STATION
Receipts, 1933-34 ............................................. $170,243.00
Expenditures, 1933-34:
Salaries ....................................................................... $85,770.60
Labor ............................................................................ 23,821.60
Stationery and office supplies ................................ 1,180.56
Scientific supplies .................................................. 2,922.62
Feed ............................................ .......................... 4,636.93
Fertilizer ...................................................................... 3,394.72
Sundry supplies .......................................................... 3,552.43
Communication service ............................................ 1,784.21
Travel ............................................................................ 6,893.64
Transportation of things ......----.......................-- ..... 1,234.99
Publications ........................................ ............. 2,182.14
Heat, light, power .................................................... 5,852.92
Contingent ......................................................... ........ 469.75
Furniture ...................................................................... 330.42
Library ................................................... .................. 1,605.59
Scientific equipment .................................................. 470.74
Tools, appliances ...................................................... 6,583.00
Livestock ..............-...................................... 1,895.88
Buildings, repairs ................................................. 3,569.63
Balance ....................................................................... 12,090.63 $170,243.00

STATION INCIDENTAL
Receipts:
Balance, 1932-33 ........................................................ $10,535.95
Receipts, 1933-34 ....................................................... 12,782.08 $ 23,318.03
Expenditures:
Salaries .......................................................................... $ ....
Labor ............................................................................ 3,802.97
Stationery and office supplies ................................ 94.61
Scientific supplies ...................................... ... 55.37
Feeds ................................. ................................ 4,625.00
Fertilizer ...................................................................... 41.75
Sundry supplies .................................................. 782.21
Communication service ............................................ 105.73
Travel ............................................................................ 101.72
Transportation of things ........................................ 389.31
Heat, light, power .......... .................................... 517.03
Contingent ............................... ....... .. .... ...... 318.23
Furniture ...................................................................... 24.60
Library ......................................................................... 25.09
Tools ............................................................................. 121.26
Livestock ...................................................................... 342.25
Buildings, repairs ....................................................... 461.83
Balance, 1933-34 .......................................................... 11,509.07 $ 23,318.03

TOMATO DISEASE INVESTIGATIONS
Receipts, 1933-34 .................... ...................................... $ 2,900.00
Expenditures:
Salaries .....................---------------....... --...........---- $ 1,691.66
Labor ............................................................................ 483.90
Scientific supplies ..................................................... 124.73
Feeds ........................................................................... 47.50


L






Annual Report, 1934 13

F ertilizer ............................................................. ...... 21.50
Sundry supplies .... ------ ---------------- 37.10
Communication service ....................................... 44.45
Travel ...................... ...................................-- -- 95.80
Transportation of things ........................................ 11.94
Heat, light, power ...................... ..................... 108.26
Contingent .......................... ........- .....- ... 20.00
Tools, appliances .-..-- ...----...........--------- 96.35
Buildings, repairs ............................... ........ 76.32
Balance .................................................................... 40.49 $ 2,900.00

STRAWBERRY DISEASE INVESTIGATIONS
Receipts, 1933-34 .............-- -----.... ------........ ---- $ 6,300.00
Expenditures:
Salaries ...................-................. $ 4,568.00
Labor .............................. ..... ................ ............. 983.34
Scientific supplies .......-....... ---.----................ .. 66.07
Feed ...........-------------------- -----...... .. 50.45
F ertilizer ................................................................... 11.19
Sundry supplies ... ----- ------ ---------- 176.63
Communication service ........................................ 8.75
Travel ......................................................... .............. 98.25
Transportation of things ........................................ 5.75
Heat, light, power ......-.....------ -..-- ..--..--------- 121.82
Scientific equipment .................................................. 6.40
Tools, appliances ........................................ 32.01
Buildings, repairs ................ ......................... 66.20
Balance ............................................... 105.14 $ 6,300.00

CITRUS DISEASES
Receipts, 1933-34 .........---..---......- .--------.--- $ 3,500.00
Expenditures:
Salaries ......................---------.... .... $ 2,526.00
Labor ......................................................----------..---... 73.00
Scientific supplies ....................... .............. 10.48
Communication service ..---.- --------------- 3.00
Travel ............................................................................ 215.75
Scientific apparatus ................................ ...... 235.40
Tools, appliances .................................... .. 69.69
Buildings, repairs ....................... .... ..... .. 365.75
Balance ...-............. ....... ......- .................... 93 $ 3,500.00

POTATO DISEASES
Receipts, 1933-34 ................................................ $ 5,250.00
Expenditures:
Salaries ...................................................................... $ 3,045.00
Labor .................. ............ ........ .................. ....... 915.79
Scientific supplies ......................... ..... ............... 124.54
Fertilizer ..................................................................... 75.46
Sundry supplies ...................................................... 293.70
Communication service ..................-....................... 54.55
Travel ............................................................................ 135.17
Transportation of things ........................................ 9.28
Heat, light, power ........ ---....... --...---- ........... 213.88
Contingent .. ......................................................... 52.50
Library ........................................................................ 2.00
Scientific equipment .............~.........................-----. 36.53
Tools, appliances ......................... ................. 131.71
Buildings, repairs ...................................................... 50.00
Balance .......................................................................... 109.89 $ 5,250.00






14 Florida Agricultural Experiment Station

PECAN DISEASES
Receipts, 1933-34 ............................................................. $ 1,750.00
Expenditures:
Salaries ........................................................................ $ 444.20
Labor ............................................................................ 52.50
Sundry supplies .......................................................... 36.42
Travel ............................................................................ 17.50
Heat, light, power .................................................... 34.22
Balance .......................................................................... 1,165.16 $ 1,750.00

CELERY DISEASES
Receipts, 1933-34 .............................................................. $ 5,250.00
Expenditures:
Salaries ........................................................................ $ 1,800.00
Labor .......................................................................... 79.45
Scientific supplies ..................................................... 736.96
Fertilizer ...................................................................... 72.70
Sundry supplies ......................................................... 40.24
Travel ............................................................................ 146.90
Transportation of things ........................................ 38.56
Heat, light, power ...................................................... 140.78
Furniture ................................................................... 99.00
Library ....................................................................... 5.00
Scientific equipment .................................................. 424.19
Tools, appliances ........................................................ 75.42
Buildings, repairs ...................................................... 160.28
Balance ........................................ ......................... 1,430.52 $ 5,250.00

FUMIGATION
Receipts, 1933-34 .............................................................. $ 3,062.50
Expenditures:
Salaries ..................................... ....................... ... $ 2,131.00
Labor ..........-......................--------....---......--- -........ 51.90
Scientific supplies ............................................. ... 21.62
Sundry supplies .......................................................... 3.30
Heat, light, power ...................................................... 22.16
Furniture ...................................................................... 89.10
Scientific equipment .......................... .............. 31.67
Balance ............................. ... ...... .. ....... 711.75 $ 3,062.50

GRAPE PESTS
Receipts, 1933-34 ........................................-- ....---- $ 3,500.00
Expenditures:
Salaries .. --------.......................... ....... $ 2,367.00
Labor ........................................................................... 307.65
Stationery and office supplies ................................ 1.50
Scientific supplies ...................................................... 55.37
Feed ................................... -......... ....... -----..............
Sundry supplies -... ---........- .............. ................. 52.56
Communication service ......................................... 51.74
Travel ............................................................................ 437.20
Fertilizer ...................................................................... 15.66
Heat, light, power ............................ ----........... .... 88.02
Furniture ..................................................................... 13.00
Tools ................................. --....-.... .................... 9.40
Buildings, repairs ..........-...............- ....... .............. 30.00
Balance .......................................................................... 70.90 $ 3,500.00







Annual Report, 1934 15

CITRUS EXPERIMENT STATION
Receipts, 1933-34 ............................---- -... .... $ 11,451.00
Expenditures:
Salaries ................................... .... $ 5,986.00
Labor ....................------------------- .------.. 2,453.85
Stationery and office supplies ................................ 6.30
Scientific supplies ..........-.....-.....-...-.------ ... 92.89
Feed ......... .................. ....-.. 228.57
Fertilizer .................................... ... 861.50
Sundry supplies .............. ................... ... 333.41
Communication service ......................... ............. 96.43
Travel .............................. .......................................... 208.46
Transportation of things .......... ..................-.---- 15.11
Heat, light, power .........................--- ---- 483.07
Contingent .............................--------- 8.75
Library .......................................-----. 14.80
Scientific equipment .................................---- 212.84
Tools ..........................-- --------- ... 276.22
Buildings, repairs ....................................---- 74.90
Balance ..................... ....................... 97.90 $ 11,451.00

EVERGLADES EXPERIMENT STATION
Receipts, 1933-34 ...................................------ ......... $ 50,339.00
Expenditures:
Salaries ......................... .... $24,534.44
Labor .......--................................. .. 15,424.39
Stationery and office supplies ............................... 134.97
Scientific supplies .....................................................--576.20
Feed .. ............. ......... ....... 888.25
Fertilizer ........................---- -.. ....... 316.92
Sundry supplies --............ ----------------- 1,112.38
Communication service ... ..................--.......... 167.12
Travel ..........................-----..--- ----....... 910.38
Transportation of things ...................................... 179.51
Heat, light, power ......................... .. ..--- ..... 2,685.91
Contingent .............................................. 32.90
Furniture .........................................23.47
Library ............................... ......................... ..... 221.30
Scientific equipment ............................------ 26.07
Tools ........................ ---- --........ 1,486.26
Livestock ...............................-..-.......----- ---. ... 23.00
Buildings, repairs ...................................................... 1,558.11
Balance .. ........................................ 37.36 $ 50,339.00

NORTH FLORIDA STATION
Receipts, 1933-34 ........................... .. ....----- .. $ 20,968.00
Expenditures:
Salaries ........ ............................... $12,487.42
Labor ...........................--- .......---------.......... -- ...... 2,436.59
Stationery and office supplies .............................. 26.89
Scientific supplies .................... ....................--- 34.05
Feed ........................................ 892.65
Fertilizer ....... ..................................... .. ...- ...... 1,220.05
Sundry supplies ............................................ ...... 871.20
Communication service ............................... 111.62
Travel ..........................-.... ......... 104.47
Transportation of things ........................................ 64.13
Heat, light, power ............................. ... ............ 664.69
Contingent .............................. ................... .... 30.74
Furniture .....................................-. 33.87
Library .......................................................................... 58.50






16 Florida Agricultural Experiment Station

Scientific equipment ..................... ---------...... ......... 148.92
Tools ............................-------....................- ........... 726.67
Livestock ......--- --.......-......................... ..... ------- 175.00
Buildings, repairs ..................................................... 862.22
Balance ......................................................................... 18.32 $ 20,968.00

SUB-TROPICAL STATION
Receipts, 1933-34 ........................................... ....... $ 10,579.00
Expenditures:
Salaries ...................... ............................................ $ 4,665.00
Labor .................................-..................................... 3,107.61
Stationery and office supplies ................................ 12.56
Scientific supplies ...................................................... 110.11
Feed ................... ..--........................----........----- -10.23
Fertilizer ...................................................................... 536.72
Sundry supplies .......................................................... 577.46
Communication service ............................................ 91.83
Travel .......................................................................... 397.20
Transportation of things ........................................ 62.67
Heat, light, power .................................................... 308.27
Contingent .................................................................. 7.53
Furniture ...................................................................... 100.75
Library .......................................................................... 10.50
Scientific equipment ................-.........-- ................. 143.93
Tools, appliances --.... --------...............-- --........ 266.12
Buildings, repairs ...................................................... 152.80
Balance ..........-............................ .............................. 17.71 $ 10,579.00

WATERMELON DISEASES
Receipts, 1933-34 ........................... ........................... $ 6,229.00
Expenditures:
Salaries .................------ ......... ........................... $ 4,821.00
Labor .......................------..........- .....-.--- -. .--- ...-- 578.63
Stationery and office supplies ................................ 21.36
Scientific supplies ...................................................... 12.57
Fertilizers ................................................... ............ 284.02
Sundry supplies ......................................................... 68.69
Communication service .......................................- .. 24.56
Travel ........................................................................... 214.05
Transportation of things .......-................................. 38.56
Heat, light, power .......-..-... ---.. .....----- ....--- 63.86
Library ........................................................................ 15.00
Tools ......................................................................... 53.32
Buildings, repairs .................................... ............... 15.75
Balance ........................................................................ 17.63 $ 6,229.00

EVERGLADES STATION, INCIDENTAL
Balance, 1932-33 ............................................................ $ 2,906.71
Receipts, 1933-34 .........................................................
Expenditures ...... ....................... ........







Annual Report, 1934


PUBLICATIONS, NEWS, RADIO
Information obtained by workers in the Experiment Station was made
available to Florida farmers in increasing quantities during the fiscal year
ending June 30, 1934, notwithstanding the fact that the number of bulletins
issued during the year showed a decrease. The year was one of adjustment
in the farm world, and important information based on research findings
was presented to farmers by means of news stories, articles in farm papers,
radio talks, and bulletins. This information was used largely by farmers
in determining intelligently their policies and practices during the trying
adjustment period.
The Experiment Station has accumulated a vast amount of information
of value to farmers of the state, and they are taking advantage of this
knowledge in ever-increasing numbers. Research information is made
available as rapidly as possible, that it may be of the greatest good.
The staff of the Editorial and Mailing Department have devoted approxi-
mately half of their time to work for the Experiment Station, while the
other half has been used by the Agricultural Extension Service. Heavy
mimeographing work for most of the Station has been done in the Mailing
Room.
BULLETIN PRINTING AND DISTRIBUTION
Only five new bulletins were printed during the year. These five totalled
248 pages, and 34,500 copies were issued. In the 47 years of its existence
the Station has published a total of 268 bulletins on farming subjects.
Distribution of all Experiment Station bulletins is handled from the
Mailing Room. A number of copies of each new work are sent to libraries
and technical workers throughout the country. Notification is sent to a
large list of Florida farmers and others, and bulletins are sent only on
request.
Following is a list of the bulletins issued during the fiscal year, showing
titles, pages and number of copies of each:
Bul. Title Pages Edition
264 Stiffs or Sweeny (Phosphorus Deficiency) in Cattle........ 28 7,500
265 Effect of Frequent Fires on Chemical Composition of
Forest Soils in the Longleaf Pine Region.................... 40 7,500
266 A Study of the Cost of Handling Citrus Fruit from the
Tree to the Car in Florida ..-.... .---------.---.--. 76 7,500
267 Studies on the Ring Spot Disease of Sugarcane................ 80 6,000
268 The Pectic Constituents of Citrus Fruits-............................. 24 6,000
SUMMARY OF BULLETINS
Brief summaries of the principal points covered in the different bulletins
are given here:
264. Stiffs or Sweeny (Phosphorus Deficiency) in Cattle. (R. B.
Becker, W. M. Neal and A. L. Shealy, pp. 28, figs. 12). Analyses of blood
plasma of range cattle suffering from the stiffs disease in certain West
Florida counties showed a deficiency of phosphorus. Analyses of forages
on the ranges confirmed this shortage. Feeding tests showed that with the
addition of phophorus to the feeds, affected animals regained their health.
265. Effect of Frequent Fires on Chemical Composition of Forest Soils
in the Longleaf Pine Region. (Frank Heyward and R. M. Barnette, pp.
40, figs. 16). Reports studies of the effect of burning, a common practice
in the region, on the soils and vegetation of the longleaf pine area. (Does
not report effect of fires on trees.) Technical bulletin.
266. A Study of the Cost of Handling Citrus Fruit from the Tree to
the Car in Florida. (H. G. Hamilton and Marvin A. Brooker, pp. 76, figs.
20). Discusses various items in the cost of handling fruit from the tree






Florida Agricultural Experiment Station


to the car, including labor, management, office, packinghouse and land,
packing equipment, field equipment, light, water and power, materials,
picking, hauling, pre-cooling, and other items. Shows changes in costs
since 1924-25 (reported in Bulletin 202), as well as factors affecting costs.
267. Studies on the Ring Spot Disease of Sugarcane. (B. A. Bourne,
pp. 80, figs. 23). Shows that the cause of ring spot is a combination of two
organisms. Gives names, history and distribution of the disease, and
describes its symptoms. Discusses resistance of various varieties of the
cane family, as well as gives the host range. Technical bulletin.
268. The Pectic Constituents of Citrus Fruits. (L. W. Gaddum, pp.
24, fig. 1). Presents data which indicate that in the orange, grapefruit
and kumquat the percentage of total pectic compounds in the albedo and
in the pulp remains constant through a considerable portion of the growth
period, that the percentage of water-soluble pectins in these tissues rises
to a maximum value just prior to the decline in total pectic content, and
then gradually declines. Technical bulletin.
PRESS BULLETINS
Seven new press bulletins were issued during the year and three old
ones were reprinted. Each was two pages in length, and 3,000 copies were
issued. Since the establishment of the Station 464 press bulletins have
been printed. Following is a list of the press bulletins issued during the
year:
No. Title Author
459 The Screw Worm Fly................................D. A. Sanders and A. N. Tissot
460 The Gladiolus Thrips................................................................J. R. W atson
461 Controlling Mole-Crickets-......................................................J. R. Watson
462 Papaya Leaf Spot.................................................................... Erdman W est
463 Anthracnose of Mango........................................................... Erdman West
464 Calendar Spraying with Lime-i W W Yothers R L Miller
Sulhpur for Pest Control on Yothers, R. L. Miller,
Citrus Trees in Florida J R. watson and W. L. Thompson
411 Ammoniacal Copper Carbonate and Other
Stainless Fungicides (Rep.) ..............................................Erdman West
412 Bordeaux Paste Treatment for Stem-End
Decay of Watermelons (Rep.)............................................Geo. F. Weber
437 Brown Patch of Lawns and Golf Greens
and Its Control (Reprint) ..........................-........................Geo. F. Weber
STATION INFORMATION IS USED BY FARM, WEEKLY AND
DAILY PRESS
Farmers and growers in Florida also were kept informed concerning
the activities of the Experiment Station through articles and news stories
printed in journals of general circulation. Use of material furnished by
the Station editors was on an even more generous scale than heretofore,
despite the economic conditions that adversely affected the publishing
business in a marked degree.
Agricultural periodicals issued in the state all utilized information
supplied from the Experiment Station editorial rooms in almost every issue.
Four of these publications ran 10 articles, consuming 395 column inches
of space, principally pertaining to major discoveries of the year. In part,
however, they consisted of monthly suggestions respecting farm work,
based on Station experiences.
Items of current interest in respect to Station programs likewise ap-
peared frequently in the farm press of the state, many of them taken from
the weekly clip-sheet. Questions and answers on farming topics, extracted
from the correspondence files at Gainesville, were printed regularly in one
journal.






Annual Report, 1934 19

Daily and weekly newspapers availed themselves liberally of the stories
relating to the Station's work, distributed once a week in the Agricultural
News Service, the clip-sheet published by the State Agricultural Extension
Service, every number of which is devoted in part to Experiment Station
findings.
Events at the Station of peculiar importance from the standpoint of
news value were covered in special stories for daily papers, some of them
going out over the Associated Press wires from Gainesville and others
having been mailed direct by the editors.
One leading daily made a regular Sunday feature of a questions and
answers department on the problems of Florida agriculture, all copy for
which came from the Station editorial staff.
Interest in Florida research existing in other states was indicated in the
use by two southern farm journals of four articles taking 43 column inches
of space.
An agricultural publication of national circulation ran a story of a
Station achievement, devoting to it five inches of space.
RADIO SERVICE
Radio talks based on Experiment Station information, many of them
made by its staff members, were delivered in increasing quantity over State
and University of Florida Radio Station WRUF and other stations from
Miami to Pensacola. In this way, a great deal of valuable research infor-
mation was made available to Florida farmers and growers at times when
it was most advantageous and useful.
All of the farm radio programs were directed by the Agricultural
Extension Service, but Experiment Station workers presented 174 talks
on the Florida Farm Hour over WRUF and approximately one-third of
the daily farm flashes to five other Florida radio stations. The talks
averaged around seven minutes each in length.
For the second year in succession, a series of 40 weekly radio talks on
gardening and ornamentals proved of outstanding interest throughout the
state. These were arranged by Assistant Director H. Harold Hume in
cooperation with the Florida Federation of Garden Clubs, and most of the
40 talks were given by Station workers. They were presented over five
Florida stations each week beginning in September and concluding in June.
SCIENTIFIC AND POPULAR ARTICLES IN JOURNALS
Members of the Station staff send direct or through the Editorial Office
many articles to popular and scientific journals. Most of these are not
edited by the Editors, but they serve admirably to disseminate information.
Following is a list of articles by staff members appearing in popular and
technical periodicals during the year:
Additions to the Aphid Fauna of Florida. A. N. Tissot. Fla. Entomolo-
gist. 17:3:37-45. 1933.
Another Powdery Mildew on Crape Myrtle. Erdman West. Phytopath.
23:1002. 1933.
A Pepper Pest New to the United States. J. R. Watson. Fla. Entomol-
ogist. 18:2:23. 1934.
A Type of Laboratory Silo and Its Use with Crotalaria. W. M. Neal
ahd R. B. Becker. Jour. Agr. Res. 47:617-625. 1933.
Composition of Feedstuffs in Relation to Nutritional Anemia in Cattle.
W. M. Neal and R. B. Becker. Jour. Agr. Res. 47:249-255. 1933.
Control of Common Melon Aphid. A. N. Tissot. Florida Grower 42:
2:13. 1934.
Earth Pearls of Citrus Roots. J. R. Watson. Florida Grower 42:5:12.
1934.






Florida Agricultural Experiment Station


Effect of Calcium Deficient Roughages upon Milk Yield and Bone
Strength in Cattle. R. B. Becker, W. M. Neal and A. L. Shealy.
Jour. Dairy Sci. 17:1-10. 1934.
Effects of Certain Environmental Factors on the Germination of the
Sporangia of Physoderma zeae-maydis. R. K. Voorhees. Jour. Agr.
Res. 47:609-615. 1933.
Experiments with Summer Cover Crops for Pecans. G. H. Blackmon.
Modern School Store 17:6-8-9. 1934.
Food Habits of Leis conformist Boisd. (Chinese Ladybeetle). J. R. Wat-
son and W. L. Thompson. Fla. Entomologist 17:2:27-29. 1933.
Food Habits of Tineola uterella. J. W. Kea. Fla. Entomologist 17:4:66.
1933.
Freight Rates on Citrus Fruits. Marvin A. Brooker. Citrus Industry.
Aug. 1933.
Giant Galls Caused by the Root-knot Nematode. G. Steiner, Edna M.
Buhrer and A. S. Rhoads. Phytopath. 24:161-163. 1934.
Gluco$ides and Minerals in Citrus Fruits. L. W. Gaddum. Proc. Fla.
State Hort. Soc. 1934.
Ground Pearls on Citrus Roots. J. R. Watson. Proc. Fla. State Hort.
Soc. 1934.
Non-Arsenical Stomach Poisons for Grasshopper Control. W. L. Thomp-
son. Fla. Entomologist 18:1:5-10. 1934.
Notes on Experimental Transmission of Bovine Anaplasmosis in Florida.
D. A. Sanders. Jour. Amer. Vet. Med. Assn. 36:6:799-805. 1933.
Pecan Cold Storage Experiments. G. H. Blackmon. National Nut News
17:2:7-8. 1934.
Pecan Kernel Storage Experiments. G. H. Blackmon. National Nut
News 16:9:9. 1933.
Powdery Mildew of Crape Myrtle, Caused by Erysipha lagerstroemiae
n. sp. Erdman West. Phytopath. 23:814-819. 1933.
Recessive Coloration in Dutch Belted Cattle. R. B. Becker. Jour. of
Heredity 24:283-286. 1933.
Reaction of Native Iris Soils in Florida. H. Harold Hume. Bul. Amer.
Iris Soc. Jan. 1934.
Results of Pecan Cover Crop Experiments. G. H. Blackmon. Proc.
Natl. Pecan Assn. 1933.
Spring Cultural Practices in Pecan Orchards. G. H. Blackmon. Natl.
Nut News 17:3:5-6. 1934.
Summer Management of Pecan Orchards. G. H. Blackmon. Natl. Nut
News 16:8:11. 1933.
Symbiotic Nitrogen Fixation in the Genus Casuarina. Harold Mowry.
Soil Sci. 36:6:4-9-425. 1933.
The Effect of Cover Crops on Growth and Yield of Pecan Trees. G. H.
Blackmon. Natl. Nut News 16:7:7-8. 1933.
The Effect on the Worm Burden of Children Infected with Necator
Americanus and Ascaris Lumbricoides. C. F. Ahmann and L. M.
Bristol. Sou. Med. Jour. 26:11:959-962. 1933.
The Growing of Roses for Cut Flowers. A. F. Camp. Proc. Fla. State
Hort. Soc. 1934.
Treats Lily Bulbs with Disinfectants to Eliminate Decay. W. B. Shippy.
Florists Review 73: 1888:13-15. 1934.
Two New Aphids of the Tribe Macrosiphini. A. N. Tissot. Fla. Ento-
mologist 18:2:17-23. 1934.
Two New Species of Oedaleothrips with Notes on Other Species. J. R.
Watson. Fla. Entomologist 17:3:48-50 and 17:4:63-64. 1933.
Two New Species of Plectothrips. J. R. Watson. Fla. Entomologist
17:2:33-34. 1933.
Why Plant Cover Crops in Florida Pecan Orchards? G. H. Blackmon.
Proc. Southeastern Pecan Grs. Assn. 28:46-54. 1934.
Zinc Sulphate as a Soil Amendment in Citrus Groves. A. F. Camp.
Proc. Fla. State Hort. Soc. 1934.






Annual Report, 1934


THE LIBRARY
A summary of some of the statistics of the library for the fiscal year
ending June 30, 1934 is given below:
Volumes in the library.............................. -- -----------..12,163
Volumes added through purchase, gift and exchange................................ 2,324
Volumes sent to the bindery........................................ 185
Pamphlets, bulletins, serials, etc., received------...........................---- ------ 9,254
Cards prepared and added to dictionary catalog............... 5,968
Cards purchased from Library of Congress for dictionary catalog........ 1,763
Books, journals, etc., lent to branch stations.. ... ............................. 301
Books, journals, etc., lent to local staff........................................... ....... 3,521
Loans from other libraries.......---- ---. -. ---------------- 112
At the end of the fiscal year the library had 12,163 bound volumes. This
number includes the volumes in the main library and in the several de-
partments. It does not include those at the various branch stations.
An outstanding piece of work accomplished during the year was the
accessioning of 2,219 volumes in the various departments. To complete
this work requires the typing of 12,000 cards. A part-time student assigned
to the library for a short time began the work which can be completed
when more assistance is available.
In February the reading room of the library was taken over for another
purpose. This made it necessary to remove the agricultural economics
collection, which had been kept in the reading room, into the stack room,
and left the library without sufficient seating room to take care of the
staff, much less of the graduate students and agricultural students who
use the library. As a result it was necessary to lend more books, the
records showing 3,521 books lent during the year in comparison to 2,514
for the previous year. This called for more work at the charging desk and
greatly increased the task of maintaining the records.
With so much increase of routine work it was necessary for the cataloger
to devote a large portion of her time to work other than cataloging. This
accounts for the preparation of fewer cards for the dictionary card catalog
than the previous year. A revision of the catalog is being made, the close
of the fiscal year finding one-fourth of the 92 drawers completed. A new
card shelf list has been instituted which is of inestimable value. This
required the typing of 12,163 cards. Bibliographical work has been much
in demand during the year.






Florida Agricultural Experiment Station


AGRICULTURAL ECONOMICS
During the fiscal year ending June 30, 1934 studies have been made
of farmers' cooperative associations, costs of citrus fruit production, cost
of handling citrus fruit from tree to car, pre-cooling and refrigeration of
citrus fruits, and farm tax delinquencies, farm mortgages and land values
in twenty-two Florida counties. Much of this work is still in progress and
reports of completed work cannot be furnished.

AGRICULTURAL SURVEY OF SOME 500 FARMS IN THE GENERAL
FARMING REGION OF NORTHWEST FLORIDA
Purnell Project No. 73 C. V. Noble and Bruce McKinley
Work on this project has been inactive during the present fiscal year.
FARMERS' COOPERATIVE ASSOCIATIONS IN FLORIDA
Purnell Project No. 154 M. A. Brooker and H. G. Hamilton
The first part of this study, entitled "Status and Legal Phases" was
published in Station bulletin 245 in April, 1932. The second part, entitled
"Organization and Management", was printed near the close of the fiscal
year 1932-33 as Station bulletin 263.
During the year information concerning all farmers' cooperative asso-
ciations chartered in Florida from August 30, 1931 to March 31, 1934,
inclusive, was obtained from the office of the Secretary of State. A classi-
fied list of these associations, corresponding with the list given in Station
bulletin 245, was mimeographed and is used as a supplement to bulletin
245, thus completing this particular information for Florida farm coopera-
tives to April 1, 1934.
Considerable progress has been made on the first of the contemplated
monographic studies of successful Florida cooperatives. The Hastings
Potato Growers' Association is being studied in detail with particular
reference to its credit operations. Data have been obtained on the operation
and management of this cooperative since its inception through the 1933-34
season. Analysis of these data is now in progress. Similar monographs
of other outstanding Florida cooperatives are contemplated.

COST OF PRODUCTION AND GROVE ORGANIZATION STUDIES OF
FLORIDA CITRUS
Purnell Project No. 186 C. V. Noble, Bruce McKinley and Zach Savage
Cost accounts were opened with 45 citrus growers cooperating in Sep-
tember, October and November of the fiscal year 1932-33. Accounts were
kept in sufficient detail on 38 grove properties to be closed at the end of
the accounting year. The accounts that were closed represented a total
of 1,364.79 acres of citrus groves located in six counties.
At or soon after the end of the accounting year each cooperator was
visited and the information necessary for closing each set of books was
obtained. Previously prepared plots of each grove showing acreage and
variety by age were carried back to the cooperator concerned.
The office work of closing the records of 37 grove properties has been
virtually completed. One account was not kept in sufficient detail to be
used in the tabulation. Acreages by counties are given in Table I.







Annual Report, 1934


TABLE I.-GROVE ACREAGES BY COUNTIES INCLUDED IN 37 COMPLETED
COST ACCOUNTS.
County Acreage
Highlands .....---.......... -------.----- ----. 288.23
Indian River ........ ... ..............------- .. . 83.27
Lake ..---..-........... ---------------- -.. 226.33
Orange .................................... ......................................... 118.45
Polk ... ................................................................................ 350.72
Saint Lucie ................-...-....... ----- .... ..-. 182.07
Total ...................................---- --------....---.... 1249.07
In these accounts records were made of data and kind of operation,
hours of man and horse labor, hours of tractor use, amounts and kinds of
fertilizers and spray materials applied, and all cash and other costs, such
as interest on the investment, unpaid labor and supervision. Returns by
size and grade of fruit, where available, were recorded in each grove account.
The closed accounts show profit or loss of each kind and age of citrus
as well as the gain or loss of the entire grove property. It was necessary
to do considerable proration of costs to the various accounts in this office,
which prolonged the closing process.
Tabulations are now in process and, when completed, comparative sum-
maries will be made and copies returned to the cooperators together with
a copy of the closed accounts.
At the time the accounts for the year 1932-33 were closed, accounts
were opened for the accounting year 1933-34 on 40 grove properties totaling
1300.91 acres.
COST OF HANDLING CITRUS FRUIT FROM THE TREE TO THE CAR
Purnell Project No. 197 M. A. Brooker and H. G. Hamilton
This study, which was undertaken to supplement and revise the findings
reported in Station bulletin 202, now out of print, has been completed and
published in Station bulletin 266. This revised bulletin has just been re-
leased from the press. Comparisons are given of the results obtained
from the earlier studies of the 1924-25 and 1925-26 seasons and similar
data secured for the 1931-32 season. A few of these comparisons may be
noted here.
1. The cost of handling packed citrus fruit from the tree to the car,
exclusive of pre-cooling, averaged 93.1 cents per box in 1924-25 and 75.9
cents per box in 1931-32. The greatest reductions were in labor and
materials.
2. The total cost of handling citrus fruit from the tree to the car
varied from 58 cents to $1.56 per box in the different packinghouses studied
in 1931-32.
3. The outstanding factor affecting cost of handling citrus fruit was
volume per packinghouse. For 14 packinghouses with volumes of more
than 200,000 boxes in 1931-32, the total handling cost was 67.2 cents per
box of packed fruit, while for 10 packinghouses with volumes of 25,000
boxes or less, the cost was $1.139 per box. Almost all items of cost were
affected, but labor and management and fixed investment expenses were
influenced most by this factor. Volume per packinghouse was also the
outstanding factor influencing packing costs in the studies of earlier sea-
sons (bulletin 202).
4. For packinghouses of approximately equal volumes, cost of handling
fruit increases rapidly with increasing investment per packinghouse.
5. The percentage of bulk fruit handled through the packinghouses







Florida Agricultural Experiment Station


studied increased from 2.9 percent of the total volume in 1924-25 to 21.1
percent in 1931-32.
This project was closed with the publication of bulletin 266.
A STUDY OF PRE-COOLING AND OF REFRIGERATION IN TRANSIT
AS AFFECTING COST OF MARKETING, QUALITY AND
PRICE OF CITRUS FRUITS
Purnell Project No. 235 M. A. Brooker
Field work was started on this project in early December, 1933. The
method used was to go to the files of the Florida Citrus Exchange in
Tampa and the Florida division of the American Fruit Growers, Inc., in
Orlando, and copy the data from the individual car manifests of shipments
of citrus fruit. The information includes the origin point, destination,
loading date, date of sale, whether or not pre-cooled, method of refrigera-
tion in transit, number of diversions in transit, whether or not stored in
transit, condition of fruit on arrival if enough decay to warrant inspection;
also all transportation, refrigeration and selling costs, and the price
received by variety, grade and size.
Twenty-four origin points of the Florida Citrus Exchange and seven
of the American Fruit Growers, Inc., were selected for the study. Fifteen
of these packinghouses were equipped with pre-cooling plants and 16 were
not so equipped. Records were secured of each car of fruit from these
31 plants to eight destinations (New York, Pittsburgh, Detroit, Cincinnati,
Chicago, Minneapolis, Kansas City and New Orleans), for the three-season
period 1930-31, 1931-32 and 1932-33.
This gave a total of approximately 11,000 records, or about 20 percent
of the total volume handled by these two organizations during the period
under consideration. Work is now in progress on these records to put them
in final shape for tabulation and analysis.
FARM TAXATION
Project No. 248 C. V. Noble
Purnell in cooperation Federal Project 6, C. W. A.
Under this emergency project a study of farm mortgage foreclosures,
farm tax delinquencies, land values and trends of values was made in 22
representative counties in cooperation with the Federal Bureau of Agri-
cultural Economics. Expenses were met by the Civil Works Administra-
tion and the data collected sent to the Bureau of Agricultural Economics
for inclusion in a nationwide study.


L







Annual Report, 1934


AGRONOMY
Through continued active cooperation with the United States Department
of Agriculture and the other departments of this station, much progress
has been made in the introduction of new crop materials as well as in
studies of cover crops, relation of crop rotation and land resting to crop
production, the cause and remedy for "white bud" in corn, and the treat-
ment and management of pasture grasses.
The outstanding new legume introduced is a cowpea which gives evi-
dence of surpassing in performance most if not all common cowpea varieties
now grown in the state for forage purposes.
Another introduction, wooly finger grass (Digitaria errantha var. stolo-
nifera), appears well adapted for use in pasture planting and is now being
propagated in quantity for field trial.
In the oat and rye variety and strain tests, two new oats, Bond from
Australia and Victoria from South America, appear to be better yielders
and more resistant to rust than the ones now commonly planted.
In the study of crotalarias as a forage crop, Crotalaria intermedia has
proved to be the best adapted and some 1,800 lots of seed have been dis-
tributed for further trial.
Breeding operations with peanuts and sweet and field corns have been
continued. New varieties that appear to have much merit have been
obtained with both types of corn, and much progress is already apparent
in certain peanut strains. With peanuts, the object is to produce better
market and hogging off and hay types than are now available.
Active pasture studies have included grazing tests of the different
grasses, influence of various fertilizers on yield, comparison of native and
improved pastures and of burned and unburned native pastures, and meth-
ods of land preparation previous to seeding. Improved pastures appear to
be from two to 10 times as productive as native pasturage when measured
by gains in pounds of beef. Centipede and Bahia grasses, with 246 and
248 pounds live weight gain per acre for the grazing season, were the best
of those under test.
Burned-over native pastures produced much more satisfactory gains
on steers than protected (non-burned) in both year-round and spring-to-
fall grazing. Nitrogen alone was the most effective pasture fertilizer on
light sandy soils, and preparation of land prior to seeding improved pasture
grasses consistently gave better results over seeding on unprepared ground.
Studies of the composition of forage, taken monthly from both burned-
over and protected, fenced ranges, are revealing fundamental information
on variation in composition due to both treatment and season.
Cover crop and fertilizer studies have been continued and methods of
land cropping have received attention.
PLANT BREEDING-PEANUTS
State Project No. 20 F. H. Hull and W. A. Carver
Selection in the hybrid strains is being practiced for yield, disease
resistance, seed dormancy, green foliage, medium bunch type plant, tan,
ovate, unpitted seed, clean well shaped pods, and some other characters.
The two leading types being selected are: (1) a large seeded Jumbo type
peanut having the above desirable characters, which fills well in Florida,
and is suitable for either hogging-off or for marketing, and (2) a hay type
peanut, which should have small seed, heavy erect top growth, fine stems,
holding leaves well, and in general a good hay type.
Approximately 200 hybrid selections were grown under observation in
1933. These were mostly hybrids of Spanish with Florida Runner or Jumbo







Florida Agricultural Experiment Station


Runner, hybrids of the other types having been largely discarded. During
the present season, 1934, 212 hybrid selections are being grown.
Crosses were made in 1933 between the best Florida selected Spanish
strain and Dixie Giant, an extra large seeded Jumbo type peanut furnished
by the U. S. Department of Agriculture. Some of the most dormant hybrid
strains descending from Spanish by Jumbo crosses have been back-crossed
to the Spanish parent, to increase the percentage of Spanish blood and the
chances of finding dormant peanuts of good market type.
PASTURE EXPERIMENTS
Hatch Project No. 27 W. E. Stokes and G. E. Ritchey
The following three phases of pasture studies have been active during
the year. These studies are in cooperation with the Bureau of Plant
Industry, U. S. D. A., and, excepting II, with the Department of Animal
Husbandry of this Station.
I. COMPARISON IN GRAZING TESTS OF THE PASTURE VALUE OF
DIFFERENT GRASSES ALONE AND IN MIXTURES
Four steers, two grade Angus and two native scrubs, were placed on
each 3% acre pasture on March 20 and removed December 1. Good gains
were made on all five pastures as is shown in the following table.
Total Gains Gains Per Gains Per Yield of Dry
Pasture of Cattle Acre Steer Clipped Grass
Ilbs. lbs. lbs. lbs. Per Acre

Bahia .................... 868 248 217 2435
Bermuda ............... 659 188 165 2115
Carpet .................... 620 177 155 1790
Centipede .............. 863 246 215 1354
Mixture ............. 672 192 168 2033

The low yield of mower clippings from the centipede grass undoubtedly
is due to its prostrate nature, making it impossible to gather a representa-
tive amount of the plants for yield determinations with a lawn mower.
The grass yields did not vary markedly from those of 1932.
Yields of ungrazed quadrats which were fertilized the same as the
pastures, namely 100 pounds of sodium nitrate per acre, were compared
with yields of adjacent quadrats which were fertilized with a 5-9-7 fertilizer
supplying the same amount of nitrogen per acre as was applied to the
pasture. From the quadrats treated with the complete fertilizer the output
did not differ materially from that of the ones treated with sodium nitrate
alone. With the exception of carpet grass, all fertilized quadrats yielded
more than the checks. Treatments were run in triplicate. The grazing
phase of this study was closed with the 1933 records, but the grass studies
were continued in 1934.
II. THE INFLUENCE OF VARIOUS FERTILIZER FORMULAS ON
THE YIELDS OF PASTURE GRASSES
This experiment has been active four years. Twenty-one different
kinds of fertilizer are used on 76 plots. The plots are mowed with a
lawn mower each month and dry weight yields are computed.
Use of phosphate or potash alone seems to have very little if any
influence on the yield of the grass while those formulas containing nitrogen
gave a very marked increase in the yields. Plots receiving the maximum
amount of nitrogen gave the highest yields. The use of lime has not shown
an increase in yield, unless possibly when used in connection with potash.







Annual Report, 1934


III. COMPARISON OF NATIVE AND IMPROVED PASTURES; COM-
PARISON OF BURNED AND UNBURNED NATIVE PASTURES
FOR BOTH NINE AND TWELVE MONTHS OF GRAZING, AND
A COMPARISON OF METHODS OF LAND PREPARATION PRE-
VIOUS TO SEEDING IMPROVED PASTURES
This experiment is in its fifth year. Steers which were grazed on each
of the partially improved pastures made over 21/, times as much gain per
acre as the steers which were grazed on the burned native pastures.
The 14 steers placed on the burned native pastures during the nine
months' growing season made good gains during the spring and early
summer months but showed a loss in weight after the July weighing. The
heaviest gains were made on the pasture which had been burned in January.
The five steers which were grazing on the year-round native pastures
made consistent gains from the January 26 weighing until the July 21
weighing, after which time they made consistent losses. The losses con-
tinued until the February 1934 weighing on the burned pasture and until
the April 1934 weighing on the unburned pasture. The total 12 months'
gains made on the burned native pasture were more than double the gains
made on the unburned native pasture.
Areas which were double-disked previous to seeding have a good stand
of carpet grass with some native grasses growing with it. The single-
disked areas have a thinner stand of carpet grass and a large amount of
competing native grass. Very little carpet grass is growing on the areas
not prepared before seeding.
CROP ROTATION STUDIES WITH CORN, COTTON, CROTALARIA
AND AUSTRIAN PEAS
Hatch Project No. 55 W. E. Stokes, J. P. Camp and G. E. Ritchey
Four years of work have been completed in this study. Marked differ-
ence does not exist between the corn yields on plots cropped continuously
to corn and those rotated with cotton. The use of legumes, apparently due
to rather poor legume yields, did not seem to affect materially the yield
of ear corn.
The plots upon which cotton and corn have been alternated annually
produced nearly four times as much cotton in 1933 as plots which have
grown cotton continuously. Plots upon which Crotalaria was grown with
the corn, in a corn and cotton rotation, produced twice as high a yield of
cotton as plots on which a legume was not grown.
Plots on which Austrian peas and Crotalaria were grown in the rotation
produced about 50 percent more cotton than those plots in'which Austrian
peas alone were used. The use of Austrian peas alone, due apparently to
rather poor yields, did not seem to affect the yield of cotton and had very
little if any influence on corn.
VARIETY TEST WORK WITH FIELD CROPS
Hatch Project No. 56 W. E. Stokes, G. E. Ritchey and J. P. Camp
Crop variety testing work with corn, cotton, oats, rye, cowpeas, peanuts,
sugarcane, soybeans and Crotalaria was conducted in 1933 and continued
during the 1934 crop season with all except cotton.
Outstanding in the crop variety testing work has been the behavior of
a new variety of cowpea, Forage Crops Office No. 04589, which appears
to be superior to the Brabham. Figure 2 illustrates the difference in growth
of this variety and the Whippoorwiil. Some seed probably will be dis-
tributed in the spring of 1935.





28 Florida Agricultural Experiment Station


Fig. 2.-The new cowpea, F. C. 04589, left center; Whippoorwill cowpea
in right center and velvet beans on extreme right.

Another outstanding find is that of two new oat varieties apparently
more highly resistant to rust than the varieties now grown in this state.
These new oats, Victoria from South America and Bond from Australia,
were obtained from the U. S. D. A. Cereal Crops Office.
Several of the new varieties of soybeans look promising as seed yielders
and hay plants but more testing is necessary.
Sugarcane variety testing work, in an effort to find more satisfactory
sirup and forage types, was carried on at Gainesville and Quincy, where
some 1,100 new sugarcanes, originating at the Everglades Station, are
under observation. Several look very promising. Of the new sugarcanes
previously released by the sugarcane office of the U. S. D. A., C. P. 807







Annual Report, 1934 29

continues to promise well, as does Co. 290, Co. 281 and several P. O. J.
canes such as 213, 36 M and others. Some of these canes appear to be as
good as or better than Cayana.
The three most satisfactory Crotalarias for use in this state appear to
be C. striata, C. spectabilis and C. intermedia,-the last the only one show-
ing real promise as a forage type.
GREEN MANURE STUDIES
Hatch Project No. 98 W. A. Leukel
This experiment is in cooperation with the Department of Chemistry and
Soils and involves field trials principally with the three most promising
species of Crotalaria striataa, spectabilis and intermedia) and accompany-
ing greenhouse and phytometer experiments with the green manure crops
used in actual field trials. The purpose is to compare the effects of the
growing and incorporation of certain green manure crops on plant growth
of crops succeeding under comparable soil conditions. In the field, corn
is now used as the indicator crop, while in the phytometer studies smaller-
growing annual crops as Sudan grass and oats are used.
The comparison of the green manure crops is made in the field on the
basis of actual field yields, while in the phytometer work the following
bases are used: (a) same quantity of dry material, (b) same quantity
of nitrogen, (c) actual field yields.
GROWTH BEHAVIOR OF PASTURE GRASSES
Hatch Project No. 100 W. A. Leukel
Work on this project has been completed and manuscript has been
prepared for publication.
IMPROVEMENT OF CORN THROUGH SELECTION AND BREEDING
Purnell Project No. 105 Fred H. Hull and W. A. Carver
Field Corn: Breeding by selection within inbred lines and their utiliza-
tion in hybrid combinations has been continued with some 400 lines. More
than half of them were tested in hybrid combination with Whatley Prolific
in 1933 and the remainder were crossed with Whatley. Hybrids of nearly
all inbred lines with Whatley are in the 1934 test. A number of these
hybrids in 1933 produced yields 25 percent or more in excess of Whatley
and were rather satisfactory from the standpoint of weevil resistance.
Some of the better lines have been intercrossed among themselves in 1934
to study their value in hybrid combinations such as single, double and
three-line crosses, and synthetic varieties.
During the winter a crossing block was grown at the Everglades Sta-
tion. In this block 200 inbred lines were crossed with Cuban Yellow Flint,
which seems to be the most satisfactory variety from that territory. The
various hybrids obtained are being grown there during the summer of 1934
in comparative tests. Two hundred inbred line, Whatley hybrids are in-
cluded in a comparative test by the North Florida Station.
Results of corn variety tests have been given to the public by letters,
radio talks and through the county agricultural agents, during the past
year. The recommendations as given in the 1932 report have not been
changed by subsequent tests.
Sweet Corn: The new variety known as Florida 191, described in the
1933 report, has been released by distributing samples of seed to growers
and furnishing seed stocks to a number of seed companies.
Conversion of the principal dent roasting ear varieties to sweet type
has been advanced two more generations by growing a winter crop at the
Everglades Station as well as the regular summer crop at Gainesville.







30 Florida Agricultural Experiment Station

The first seed of a sweet strain of Snowflake were obtained with the
winter crop in the Everglades. If this corn proves to be generally satis-
factory it will be released as a new variety without further testing or
selection.
A hybrid strain known as Florida 671, obtained by selection from a cross
between Snowflake and Long Island Beauty, has appeared rather promis-
ing in the summer crops of 1933 and 1934 at Gainesville and in the inter-
vening winter crop in the Everglades. This strain is a true sweet corn
with very good husk protection against worm damage. It is a few days
earlier and a little smaller than Snowflake. The table quality appears to
be quite satisfactory.
A small increase plot of Florida 671 sweet corn was planted in the
spring of 1934 and the crop will very probably be distributed in small
samples to growers and seedsmen.
A mimeographed circular, "Sweet Corn in the Field and Garden," was
compiled and nearly a thousand copies distributed.
EFFECT OF TIME OF PLANTING OF CORN ON FORAGE AND
GRAIN YIELDS
State Project No. 106 W. E. Stokes and F. H. Hull
This project was brought to a close with the information on the crop
of 1933. The data indicate that for the Gainesville area corn planting,
for best results, should be done as early as danger from cold damage is
past. This means late February or early March. April, May and June
plantings invariably give less satisfactory results than earlier plantings.

CROP ADAPTATION STUDIES
Hatch Project No. 107 W. E. Stokes and G. E. Ritchey
This project is conducted in cooperation with the Division of Forage
Crops and Diseases, Bureau of Plant Industry, U. S. D. A., and was con-
tinued as in the past.
Four hundred and four kinds of plants were grown in the introduction
garden during the season of 1933 and 1934, as follows: Crotalarias 78,
grasses 86, miscellaneous 61, pigeon peas 40, soybeans 119, and winter
legumes 20. In addition, several plantings were made in the greenhouse.
A number of the grasses have shown signs of promise as pasture
grasses and have been transferred to the local pastures for test under
grazing conditions. Included among them are Digitaria errantha, var.
stolonifera, D. pentzii, D. polevansii, Poa arachnifera, Pennisetum com-
planatum, and a few others.
In addition to the newly introduced plants, several promising native
grasses and legumes have been planted and will be studied from the stand-
point of their forage value.
The use of rabbits for certain palatability and grazing studies is proving
satisfactory.
FERTILIZATION OF PASTURE AND FORAGE GRASSES
Hatch Project No. 120 W. A. Leukel and J. P. Camp
Results of the work on the effects of nitrate fertilization on growth
behavior and relative composition of pasture grasses have been prepared
for publication.
FERTILIZATION OF NAPIER GRASS
Fertilization of Napier grass has been continued. One hundred pounds
of nitrate of soda was substituted for the complete fertilizer used the







Annual Report, 1934


previous season. The plants were permitted to attain a stage of growth
appropriate for silage purposes. All plots were cut for silage November 3,
1933.
YIELD OF NAPIER GRASS SILAGE NOVEMBER 3, 1933:
Green Dry Weight
Weight Weight Dry Ensilage
Treatment Per Acre Per Acre Matter Per Acre
lbs. lbs. Percent Tons

Check .......................----- ..------..... 8,225 2,838 34.5 4.112
Sodium nitrate ................-----.--- 16,190 5,585 34.5 8.095
Manure ............... .-------...... 18,780 6,480 34.5 9.390
Manure and sodium nitrate...... 21,650 7,470 34.5 10.325

COMPOSITION OF BURNED AND UNBURNED RANGE
PASTURE GRASSES
Pasture grasses from areas on the ranges were collected at 30 day
intervals over a period of 15 months. These grasses were taken from
areas treated as follows: burned and grazed, burned and not grazed, un-
burned and grazed, and unburned and ungrazed.
Work thus far showed a gradual increase in percentage of dry matter
from the burned areas ranging from 35 percent in early spring for young
growth to 65 percent at the close of the season when the ranges were again
burned. Total nitrogen, phosphorus and potassium decreased rapidly dur-
ing this period. The ash (calcium, silica and magnesium) showed little
variation.
In the unburned pastures the lowest percentage of dry matter (53
percent) appeared in midsummer. At this time the total nitrogen, phos-
phorus and potassium was at its highest but not as high as that in grasses
from the burned areas.
Mineral and protein content of these grasses was much lower than that
from tame pasture grasses while the silica content was high.
COMPOSITION STUDIES ON SWEET AND FIELD CORN
A preliminary study is under way on the relative composition of sweet
and field corn and its relation to the quality and palatability of such corn.
DATE OF SEEDING AND PHOSPHATE REQUIREMENTS OF WINTER
LEGUMES AND THEIR EFFECT UPON SUBSEQUENT CROPS
State Project No. 153 J. D. Warner
Work on this project has been inactive during the present year.
RATIO OF ORGANIC TO INOGANIC NITROGEN IN MIXED
FERTILIZER FOR COTTON
State Project No. 159 J. D. Warner
Work on this project has been inactive during the present year.
CORN FERTILIZER EXPERIMENTS
State Project No. 163 W. E. Stokes, J. D. Warner, and J. P. Camp
Accumulation of results over a four-year period from many different
soil types shows a wide range of the response of corn to application of
phosphate, nitrogen and potash. It is evident that moisture conditions
determine to some extent the efficiency of a fertilizer, but it is a significant
fact that soil type and cropping systems likewise have considerable bearing
upon the efficiency of any given element in a complete fertilizer.







Florida Agricultural Experiment Station


On the light sandy soils of central Florida, phosphate, nitrogen and
potash singly and in numerous combinations have failed, over a period of
years, to give a profitable increase in the yield of corn. During certain
very favorable seasons nitrogen has stimulated yield markedly, but on such
light sandy soils the slightest adverse weather conditions seem to mask
the effect of nitrogen almost entirely.
In contrast to these findings, the results show that corn on the heavier
types of soil in Northwest Florida responds markedly to applications of
phosphate, nitrogen and potash. The effects of these elements upon the
yield of corn on Norfolk sandy loam soil in Gadsden County, 1933, are
shown in the table below. Fertilizers of indicated analyses were applied
at the rate of 400 pounds per acre. Yields are given in bushels per acre.

PHOSPHATE NITROGEN POTASH
P-N-K Bu. P-N-K Bu. P-N-K Bu.
No Fert. ........ 4.9 No. Fert .......- 4.9 No. Fert. ........ 4.9
4-0-0........... ...... 8.1 0-4-0 5.7 4-4-0.................... 11.0
8-0-0 .................. 8.6 0-8-0...............I.. 4.6 4-4-4...............- 15.2
0-4-4.... ... ....... 8.8 8-0-4 ................. 13.5 8-8-0.................... 14.0
4-4-4... .......... 15.2 8-4-4................. 16.0 8-8-4.................... 18.6
8-4-4.......-........... 16.0 8-8-4.................. 18.6 8-8-8................... 20.3
These results are typical of the findings on a number of fields in
Northwest Florida where commercial fertilizers have been used very
sparingly or not at all over a long period of years. It will be noted that
a desirable fertilizer for such soil and cropping conditions must carry
considerable phosphate and potash. When the need for these two elements
is supplied nitrogen may be relied upon to give a satisfactory increase in
yield. Significant is the fact, however, that nitrogen alone is of but little
value as a fertilizer for corn under the conditions found on many fields
in that area. This work will be continued in Alachua, Suwannee, Calhoun
and Jackson counties.
SOURCES OF NITROGEN FOR SIDE-DRESSING CORN
Seven of the leading sources of nitrogen have been in comparative test
in Central and Northwest Florida for a period of four years. The results
fail to show marked superiority of any one of the sources of nitrogen as
indicated by the increase in the yield of corn. During 1933 nitrate of soda
gave the largest increase in yield, followed closely by the other sources
in the test.
THE RESPONSE OF THE CORN PLANT TO SOME OF THE LESS
ABUNDANT ELEMENTS
In cooperation with the Department of Chemistry and Soils, Project 220,
zinc sulfate has been included as one of the special treatments in Agronomy
Project 163 of the fertilizer experiments with corn, since where corn suffers
from "white bud" or chlorosis no kind or quantity of the usual commercial
fertilizer has been found to relieve this trouble; while zinc sulfate did so.
Before results can be obtained on the value of the usual elements consid-
ered as needed plant food materials in ordinary fertilizers: namely, nitrogen,
phosphorus and potassium, the zinc deficiency therefore needs to be supplied.
Time, method and rates of application of zinc sulfate to corn, as well as
residual effect of zinc sulfate on corn on several soil types, are all con-
sidered in connection with the use of fertilizer on corn.







Annual Report, 1934


A STUDY OF CROTALARIA AS A FORAGE CROP
State Project No. 174 W. E. Stokes and G. E. Ritchey
This project, in cooperation with the Bureau of Plant Industry, U. S.
D. A., is in its fourth year.
In the spring of 1933 about 18 acres of Crotalaria intermedia, 1 acre
each of C. anagyroides, C. goreensis, C. grantiana, C. lanceolata and C.
usaramoensis was sown for use in the laboratory silos. The following table
gives the dates on which each species was cut and delivered to the labora-
tory silo and the yield of each.
Yield Green
Species Date Cut Weight Per Acre
anagyroides ........-..... .................... Sept. 27 4.91 tons
goreensis ........................Sept. 27 6.45 tons
grantiana ......-----.... .......-- .....July 25 2.96 tons
intermedia ..................... .. --Sept. 27 5.30 tons
lanceolata -................... .....- ..... .....July 26 4.02 tons
Sept. 27 5.19 tons
usaramoensis ....... .....................July 25 2.14 tons
On September 12, 281/2 tons of green material of Crotalaria intermedia
was delivered to the silo for use in feeding tests with dairy cows. The
yields were from 3.6 tons to 9.8 tons green material per acre, with the
average acre yield of all fields 5.5 tons.
About one acre of Crotalaria intermedia was cut September 21 for hay.
A portion, bound into bundles and shocked, dried nicely. The yield of dried
hay was 2.2 tons per acre.
About 1,100 pounds of Crotalaria intermedia seed was harvested in the
fall of 1933. A portion of this was distributed to over 1,800 growers in
Florida.
Feeding tests with the Crotalaria silage and hay are reported by the
Animal Husbandry Department.
A STUDY OF CROTALARIA AS A FORAGE CROP FOR RABBITS
State Project No. 177 Geo. E. Ritchey
Work on this project has been completed and manuscript is being pre-
pared for publication.
A STUDY OF CHLOROSISS" IN CORN PLANTS AND OTHER FIELD
CROP PLANTS
Adams Project No. 220 R. M. Barnette and J. P. Camp
Information on this project will be found in the report of the Department
of Chemistry and Soils, this being a cooperative project.
A STUDY OF THE DEVELOPMENT AND DETERIORATION OF ROOTS
IN RELATION TO THE GROWTH OF PASTURE PLANTS GROWN
UNDER DIFFERENT FERTILIZER AND CUTTING
TREATMENTS
Adams Project No. 243 W. A. Leukel
Observations and studies on the root growth of grasses are being
continued. In case of plants grown to maturity, the roots of the previous
season's growth appear to furnish mineral nutrients for the new stolon
top and root growth during the early growth period. This new growth
also utilizes the previously elaborated and stored organic foods in the old
stolons of the plant. When these organic foods are exhausted the new
plant system has sufficient root and top growth to supply and elaborate
plant materials for its own subsistence. At this time the old stolon and







Florida Agricultural Experiment Station


roots deteriorate. In case of plants cut frequently, the different plants
are in a more vegetative condition and send out new growth from all parts
of the old stolon. The old stolon, in a more vegetative condition, appears
to persist over a longer period the following season.
Analyses made on stolons and roots of differently treated plants show
interesting correlations in regard to nitrogen, phosphorus and potassium.
The percentage of nitrogen in the stolons of the differently treated plants
varies inversely with the frequency of cutting. On a quantity basis the
same relation exists. The percentage of phosphorus and potassium appears
to be higher in stolons of the frequently cut plants.
In the roots of the plants the percentage of nitrogen and phosphorus
varies inversely with the frequency of cutting.
Plants cut frequently and those in the seed stage of growth showed
less variations in regard to percentage of potassium. On a quantity basis
potassium varies inversely with the frequency of cutting.
As previously reported, plants grown to maturity produced larger and
heavier root systems. The roots of frequently cut plants, although less
extensive, appeared to be less fibrous and woody and in a more succulent
vegetative condition.
PRELIMINARY STACK SILO EXPERIMENTS
Some work on the storage of sugarcane and Napier grass in stack silos
and semi-trench and stack silos was conducted in 1931, 1932, 1933 and 1934.
The methods have been to run these crops through the ensilage cutter,
stack the material on top of the ground and cover with approximately 15
inches of soil (Norfolk sand), and in other instances to dig a trench two
and one-half feet deep and as wide and long as necessary and fill trench
with ensilage material, then continue stacking until the pile was four feet
above the ground line after which two feet of soil was uniformly applied
over the entire exposed stack of ensilage.
Exposure of the ensilage material to the air resulted in very heavy
loss. Where only 15 inches of soil covering was used approximately 12
inches of spoiled ensilage was observed on the top and sides of the stack.
Where the ensilage material was covered with two feet of soil, three to 10
inches of spoilage occurred on the top and sides of the stack and next to
the trench wall. No spoilage occurred on the bottom. Spoilage next
to the sides of the trench varied from practically none to as much as 12
to 18 inches, evidently depending on how well the ensilage material was
packed against the sides.
A stack silo of sugarcane ensilage put up in November, 1932, and
opened in June, 1934, showed, by weight, approximately 65 percent good
silage. This was an entirely above ground stack covered with two feet
of soil.
The proportion of good to spoiled silage in stack silos is somewhat
dependent on the size and shape of the stack and some work on size and
shape of stack silos in relation to keeping quality is contemplated this
season with sugarcane and Napier grass.







Annual Report, 1934


ANIMAL HUSBANDRY
In research work with livestock, it is important to maintain herds of
the various classes of farm animals from which similar groups of animals
may be obtained, and to know the breeding, feeding and management of
animals used in all projects. Valuable information is obtained from the
records of these herds in addition to that from animals assigned to the
separate projects. These herds include dairy cattle, beef cattle and swine.
State Projects Numbers 224, 225, 226, 227, 228 and 229, pertaining to
poultry problems and under the leadership of N. R. Mehrhof, M. W. Emmel
and W. F. Ward, are reported under West Central Florida Experiment
Station.
DAIRY HERD
Daily milk records have been kept and are reasonably complete back
to 1917. During the past five years, the earlier records have been assembled
into workable form and a number of practical studies applicable to the
management of dairy cattle in Florida have been made.
Feeding and management practices have been continued as uniformly
as possible, that records may be comparable from year to year. Salt, bone-
meal and "salt sick" mineral (iron-copper-salt) are supplied continuously,
and records of consumption of these minerals are kept.
The Experiment Station is again the recipient of a richly-bred young
Jersey bull, from Randleigh Farm of New York, the gift of Mr. William R.
Kenan, Jr. This young bull, Floss Duke's Count 357288, due to line breed-
ing, has the famous Jersey cow, Sophie 19th of Hood Farm as 39 percent
of his immediate ancestry. This includes animals with creditable records
of production as well as transmission of the ability to produce milk and
butter-fat. The present senior herd sire, Sophie 19th's Victor 81st, was
an earlier gift from Mr. Kenan.
Pebble Hill Matador 284373, junior herd sire, was culled from the herd
during the year for failure to transmit sufficient producing ability to his
female progeny.
Four Jersey heifers were added to the herd by purchase from the Oak-
wood Farm, North Carolina. The Oakwood herd is one of the outstanding
herds in the Southeast, with many gold and silver medal records to its
credit. Results of this replacement of a part of the unproductive daughters
of Pebble Hill Matador should be evident in the production of the herd
this coming year.
During the year the following cows qualified for Register of Merit:
lbs. milk
Florida Heiress Lassie 601175................ 7,202 5.67%, 408.71 lbs. fat AA
Sophie's Majesty's Heiress F. 715637.... 8,772 5.29%, 464.19 lbs. fat AAA
Florida's Majesty Noble Lass 792758* 8,237 5.15%, 424.35 lbs. fat AAA
Florida Wonder Heart 839769................ 9,112 5.55%, 505.78 lbs. fat AA
Florida Fontaine Marie 839772*............ 7,749 5.60%, 434.19 lbs. fat AAA
These two established new state records in the 305-day class.
The health of the herd is closely guarded. The tuberculin test was
applied June 8, 1934, and no reactors were found within the herd.
BEEF CATTLE HERD
The beef cattle herd consists of native cows, grade Hereford cows and
heifers, and four recently acquired purebred Hereford heifers. The herd
is headed by a registered Hereford bull. Other breeds are used in studies
conducted at the various branch stations in the state.
Since the native Florida cow must be depended upon to furnish the
foundation on which the future beef cattle industry of the state will be







Florida Agricultural Experiment Station


built, it was deemed important to begin experimental studies with native
cattle. These cows are used to show the improvement made in beef
qualities in the offspring when they are bred to a good purebred beef bull.
Several first-cross calves have already been obtained. Birth weights and
rates of growth of these grade calves are recorded.
The herd is kept on improved pasture during the grazing season. Sev-
eral acres have been sown to improved grasses during the past year,
thereby adding greatly to the available grazing area for the cattle. In
the winter months they are used in practical studies to determine the most
economical method for wintering a breeding herd.
SWINE HERD
A purebred herd of swine is maintained to furnish "feeder" shotes for
use in projects in swine production and for studies in herd management.
The feeding value of various field crops in pork production is under deter-
mination, with these crops "hogged off" in the field. Birth weights are
kept on all pigs, and brood sows are being selected for prolificacy.
The brood sows and pigs are kept at all times in fields that have been
planted to some grazing crop, since previous work shows that it is practical
and profitable to control internal parasites by using a systematic rotation
of various forage crops for swine grazing. When parasites are controlled
through sanitation it has been found that more pigs will be raised per
litter, that the pigs will make better gains, and that a more uniform lot
of "feeder" shotes will be raised.
Rigid selection for the desirable market type is practiced within the
herd. Selection is also made for uniformity in conformation.
POULTRY INVESTIGATIONS
Projects on feeding and management of chicks, laying hens and turkeys
are conducted at the West Central Florida Experiment Station (Chinsegut
Hill), Brooksville, in cooperation with the Animal Husbandry Division,
Bureau of Animal Industry, U. S. Department of Agriculture. Plans have
been made for the establishment of an experimental flock of birds for the
purpose of beginning important breeding studies.
Feeding projects include a study of various feeds used in fattening
broilers and fryers, a comparison of those used for egg production, and
the use of peanuts and peanut products in rearing turkeys. Management
studies include projects on the rearing of chicks in confinement versus
range, lights versus no lights for egg production, and the importance of
range rotation in poultry production. Data on feed consumption, egg
production, and flock mortality are being obtained on all groups of birds.
Experimental work with poultry was enlarged during the past year
with the addition of three projects at the Florida National Egg-Laying
Contest at Chipley. These projects include studies on the value of various
feeds and the importance of lights for egg production.
Quality of eggs and factors affecting quality are studied in cooperation
with the Department of Home Economics. Cooperative work with the
Department of Chemistry includes analyses of poultry manure in which
various drying materials were used on the dropping boards.
THE NUTRITION LABORATORY
Analytical work of the department has been carried on in the nutrition
laboratory. During the first four years (1929-1933) a total of about 500
samples were accumulated and analyzed for the various mineral and
organic constituents. During the past year almost 1,000 feed and excreta
samples have been taken. This great increase is due to the extension of







Annual Report, 1934


feeding trials with beef cattle, studies on the ensilability of Florida forages
in an attempt to find the best winter roughages, and the determination of
the digestibility of several of the feeds that are more or less peculiar to
the Florida peninsula.
Regular blood analyses have been conducted with all experimental
animals. Studies of bone composition have been made with certain of the
calcium or phosphorus deficient cattle.
The toxic principle of Crotalaria spectabilis Roth was isolated and
purified in the laboratory. A method for the electrolytic determination of
copper is being perfected. This method will be used in the study of forages
and animal tissues in the "salt sick" investigations.

VETERINARY SERVICE AND DIAGNOSTIC LABORATORY
Veterinarians in this department have rendered assistance in diagnosing,
handling and treating diseases of livestock of the various departments of
the University as well as at the branch stations at Belle Glade, Brooksville,
and Quincy. Diagnoses were made on diseased animals and specimens,
including blood and various tissues, received at the laboratory as follows:
poultry, 253; cattle, 228; swine, 298; horses, 23; goats, 80; and sheep, 80.

THE ETIOLOGY OF FOWL PARALYSIS (NEUROLYMPHOMATOSIS
GALLINARIUM PAPPENHEIMER)
State Project No. 119 M. W. Emmel
Certain micro-organisms of the paratyphoid and typhoid groups of
bacteria have been isolated from young birds affected with enteritis and
in a few instances from birds affected with extremely acute cases of fowl
paralysis. Numerous investigators have shown by statistics that there
is a high incidence of coccidiosis, roundworm and tapeworm infestations
associated with this disease.
Cases of fowl paralysis have been induced in experimental birds by
means of micro-organisms of the paratyphoid or typhoid groups adminis-
tered orally following artificially induced cases of chronic coccidiosis and
roundworm infestation. Birds exposed to these micro-organisms in a similar
manner but not affected with chronic intestinal parasitism failed to contract
the disease.
The incubation period of fowl paralysis so induced is from 30 to 120
days. Typical cases of fowl paralysis have also been induced by the intra-
venous injection of certain micro-organisms of the paratyphoid and typhoid
groups.
Salmonella aertrycke has been found the most common cause of naturally
occurring outbreaks of fowl paralysis.
DEFICIENCIES IN FEEDS USED IN CATTLE RATIONS
Purnell Project No. 133 R. B. Becker and W. M. Neal
This outlined project is divided into four active phases at present:
(1) nutritional anemia, (2) calcium deficiency, (3) phosphorus deficiency,
and (4) the "paces".
Nutritional Anemia: Controlled feeding trials were interrupted due to
a serious infestation of the experimental animals with coccidiosis probably
due largely to the lowered resistance from inadequate mineral supplements
in the rations.
Analyses of the soils, under supervision of Doctor O. C. Bryan, are
practically completed. This endeavor covers samples of 50 soils, taken
at different depths, and representing a large proportion of the affected types
of range in the state.







Florida Agricultural Experiment Station


Blood analyses of experimental animals were made at weekly intervals.
Natal grass hay, used in all of the controlled feeding trials, is now
being subjected to a determination of its digestibility, using four steers.
A large group of forages and animal tissues accumulated during earlier
phases of the investigation are being analyzed this year.
Calcium Deficiency: Use of bonemeal with locally-grown roughages in
the rations of dairy cows was continued. An analysis of the records com-
pleted recently verifies earlier findings as to the value of the bonemeal to
supplement the local feeds.
Phosphorus Deficiency: The data from the study of stiffs or "sweeny"
affecting cattle on a number of ranges in Florida was assembled and pub-
lished in bulletin 264. Observations as to the extent of the condition on
different types of ranges will be continued.
"Paces": The condition known as "paces" affecting some cattle on
certain types of ranges in the state has been under investigation, having
been contacted first by the present workers in 1929. Autopsies have been
conducted and tissues obtained for study. Forage crops are collected
systematically for chemical analysis. Cattlemen are cooperating with their
observations of the condition, and with access to animals. Dr. C. F. Ahmann
is cooperating with studies of the tissues and Dr. L. W. Gaddum is co-
operating with other phases of the investigation.
COMPARISONS OF VARIOUS GRAZING CROPS WITH DRY LOT
FEEDING FOR PORK PRODUCTION
Hatch Project No. 136 W. W. Henley
It is important that spring farrowed pigs be finished for market as
early in the fall as possible, since the market is generally highest in the
early fall. In this project early grazing crops are used to fatten shots
for the early fall market.
Six two-acre areas were planted to the following crops: Lot 1, Spanish
peanuts and corn (one acre each); Lot II, Spanish peanuts; Lot III, corn;
Lot IV, chufas; Lot V, chufas, supplemented with fish meal; and Lot VI,
Spanish peanuts and sweet potatoes (one acre each).
On July 17, 1933, 24 shotes averaging 112 pounds each were divided
into three lots of eight shotes each, designated as Lots I, III, and VII. Lot
I was grazed on Spanish peanuts and corn, Lot III was grazed on corn
(supplemented with fish meal), while Lot VII was fed a ration consisting
of 10 parts corn and 1 part fish meal ad libitum in a dry lot.
August 1, 1933, 32 shotes averaging 110 pounds each were divided into
four lots of eight shotes each designated as Lots II; IV; V; and VI. Lot II
was grazed on Spanish peanuts; Lot IV on chufas alone; Lot V on chufas
supplemented with fish meal; and Lot VI on Spanish peanuts and sweet
potatoes (one acre each). The shotes used on these different feeds were
of uniform type and breeding.
The gains made by the shotes on the various crops during the 1933
grazing season rank as follows: 1st, corn; 2nd, Spanish peanuts and sweet
potatoes; 3rd, Spanish peanuts and corn (one acre each); 4th, chufas; 5th,
chufas supplemented with fish meal; and 6th, Spanish peanuts.
The yield of chufas was very low on the area on which the shotes
received fish meal as supplemental feed. In fact, the yield was much lower
than that where the chufas were the sole source of feed. This low yield
in the former case caused the chufas alone to rank highest in pork pro-
duction. However, the daily gain during the period the chufas were avail-
able was greater for the chufas supplemented with fish meal.







Annual Report, 1934


THE VALUE OF GRAZING FOR FATTENING CATTLE IN BEEF
PRODUCTION
State Project No. 137* A. L. Shealy
Grazing season for 1933 began March 20 and ended December 1. The
steers consisted of 10 grade Angus and 10 natives. These 20 steers were
divided into five lots of four each, two grade Angus and two natives being
placed in each lot. The steers were grazed on five 3.5 acre pastures as
follows: Lot I, carpet grass; Lot II, Bermuda grass; Lot III, centipede
grass; Lot IV, Bahia grass; and Lot V, mixture of carpet, Bermuda, Bahia,
and Dallis grasses.
The steers received no supplemental feed during the grazing season.
Salt and steamed bonemeal were provided in mineral boxes, the steers
having access to these minerals at all times.
For the 1933 grazing season the following is the order in which the
gains were made by the steers in the different pastures: 1st, Bahia; 2nd,
centipede; 3rd, mixture; 4th, Bermuda, and 5th, carpet.
This season completed a five-year grazing period for all pastures except
centipede which has been used for four years in these studies. All data
covering the five-year period will be arranged for a manuscript on this
work. Active work was suspended on this project at the close of the 1933
season.
This project was conducted in cooperation with the Agronomy Depart-
ment.

RELATION OF CONFORMATION AND ANATOMY OF THE DAIRY
COW TO HER MILK AND BUTTERFAT PRODUCTION
State Project No. 140 R. B. Becker
A large proportion of old cows was eliminated from the herd during
the previous fiscal year. In 1933-1934, only one cow became available for
body measurements. This animal, with 21 such records obtained earlier,
brings the total up to 22 records contributed by the Florida Station to this
project. A number of other states are cooperating with the Bureau of
Dairy Industry, United States Department of Agriculture, in this study
of the relation of conformation of the cow to her production.
ANAPLASMOSIS IN CATTLE
Purnell Project No. 149 D. A. Sanders
Experimental studies on anaplasmosis in cattle were discontinued
August 1, 1933, and the results of this work were given in an article entitled
"Notes on the Experimental Transmissions of Bovine Anaplasmosis in
Florida" presented at the Seventieth Annual Meeting of the American
Veterinary Medical Association in August, 1933, and published in Vol.
LXXXIII N. S. Vol. 36, No. 6, of the official Journal of the American Veteri-
nary Medical Association.
FATTENING FALL PIGS FOR SPRING MARKET
State Project No. 160 W. W. Henley
In the spring of 1933 three two-acre areas were planted to the following
crops: Lot I, runner peanuts; Lot II, sweet potatoes; and Lot III, sweet
potatoes and runner peanuts (one acre each).
On December 14, 1933, 24 fall farrowed pigs, of uniform type and breed-
ing, averaging 68.3 pounds each, were divided into three lots of eight pigs
each and turned on the crops mentioned above.
See Agronomy Project No. 27.







Florida Agricultural Experiment Station


Yields of peanuts and potatoes were good. Gains made by the shotes
on the various crops rank as follows: 1st, peanuts and sweet potatoes (one
acre each); 2nd, sweet potatoes; and 3rd, runner peanuts. The same areas
have been planted for the 1934-1935 grazing season.
A STUDY OF FEEDING VALUE OF CROTALARIAS
State Project No. 175 R. B. Becker, W. M. Neal and A. L. Shealy
As the result of palatability tests on several varieties of crotalarias as
silages, in which two herds of 49 and 51 head of cattle were given free
choice of these feeds, Crotalaria intermedia was found to be the first choice.
This silage was chosen, therefore, to be used in the feeding trials, conducted
with dairy cows during the next three years. Twenty-five tons of C. inter-
media were ensiled and fed in the first comparative feeding trial in which
this silage was compared with No. 1 alfalfa hay. Eight cows were used. The
experimental feeds were supplemented with a limited amount of corn
silage and a concentrate mixture which provided approximately 16 percent
total crude protein. Salt and bonemeal consumption was recorded during
the trial. It appears from results obtained that the forage deserves a trial
under wider conditions over the state.
A digestion trial using C. intermedia silage was conducted with four
steers during the past winter, the analyses for which are in progress. C.
intermedia was used as a pasture crop with four head of cattle which about
maintained their weight, even though the forage was in a rather late stage
of maturity at the time of the trial. Naturally-cured C. intermedia hay
cut late in the season was offered to mules in addition to their regular
rations. The product was stemmy, so a consumption of only 25.5 percent
of the long hay was all that might be expected. The shattered leaves were
consumed to a total of 52.75 percent, which indicates that the crop should
be cut in full leaf and without excess stems, to make the most palatable
product.
The forage used in this project was provided by the Agronomy Depart-
ment, and the Office of Forage Crops and Diseases, United States Depart-
ment of Agriculture.
COMPARISON OF VARIOUS POULTRY VERMIFUGES FOR THEIR
EFFICACY AND EFFECT ON EGG PRODUCTION
State Project No. 178
Work on this project was discontinued with the 1933 report, and the
publication of "A Preliminary Report on the Study of Poultry Vermifuges"
in the Journal of American Veterinary Medical Association Vol. 36, 1:61-75,
July 1933.
SWINE FIELD EXPERIMENT
State Project No. 179 W. W. Henley
This project has been inactive this year.
THE DETERMINATION OF DIGESTIBILITY COEFFICIENTS FOR
CROTALARIA HAY
State Project No. 188 W. M. Neal and R. B. Becker
Four mature and barren cows were used in conducting digestibility
trials with both naturally cured and artificially dried Crotalaria intermedia
hay. The trials were of 10 days' duration, after a 10-day preliminary
period, using hay as the sole feed. Consumption of the hay was inadequate
for maintenance, irregular, and there was an excessive refusal. The co-
efficients determined are not considered reliable. In some cases they were
negative.







Annual Report, 1934


No indications of any toxicity of the C. intermedia hay were observed
when the animals were autopsied at the end of the trials.
It is planned to repeat these trials with hay made at an earlier stage
of maturity.
The hay used in this trial was produced cooperatively by the Agronomy
Department and the Office of Forage Crops and Diseases, United States
Department of Agriculture.
THE EFFECT OF FEEDING CROTALARIA SEED TO CHICKENS AND
OTHER BIRDS
State Project No. 192 M. W. Emmel
Further studies have been made on birds affected with Crotalaria
spectabilis seed poisoning. Gross and histopathological studies have been
made which showed that a severe anemia is often present in chronic cases
of poisoning. This anemia is caused by a marked decrease in the number
of erythrocytes and an increase of the vacuolar lymphocytes. The anemia
seemed to be associated with the development of ascites.
Other diagnostic lesions are: petechiae of the serious membrane, visceral
fat, coronary fat and myocardium in acute cases; necrotic enteritis, par-
ticularly of the duodenum; the liver is extremely dark, usually presenting
a marbled appearance with a few areas being light brown in color; gray
foci are found on the surface of the liver.
The most important microscopic lesions were: cloudy swelling of the
parenchymatous tissue, heart muscle and smooth muscle of the viscera with
more or less accompanying edema; extensive passive congestion occurred;
and necrosis of splenic and hepatic cells.
These studies were made on 21 birds.
IMPROVING THE SIZE AND QUALITY OF NATIVE CATTLE BY THE
USE OF PUREBRED BULLS OF VARIOUS BREEDS
Project No. 194
The work of this project is now included in Project 215.
A STUDY OF THE ENSILABILITY OF FLORIDA FORAGE CROPS
State Project No. 213 W. M. Neal and R. B. Becker
The method of study previously adopted whereby the ensilability of
forage crops is tested by comparing the weight and composition of a weighed
bag of the cut forage placed in the silo with the weight and composition
of the material after ensiling, has been continued. Weights of the total
material ensiled and silage removed were obtained also.
The following forages have been studied in the past year, many of the
analyses not yet being completed: Crotalaria intermedia, two bags in
experimental pit silos, and five bags in a 25-ton upright silo; C. goreensis,
C. anagyroides, C. grantiana, C. lanceolota, C. usaramoensis, and field corn,
one bag each in experimental pit silos; Cayana 10 sugarcane, Texas seeded
ribbon cane sorghum, and napier grass, six bags each in semi-trench silos;
and napier grass, two bags in a stack silo.
Weights obtained with sugarcane and sorghum were high due to water
seepage into the silos during the unusually heavy spring rains. Silage
produced in the experimental pit silos was used in conjunction with Project
No. 175 in testing the palatability of the various crotalarias as silage. The
silage in the trench silos was used in State Project No. 241. The crota-
larias were grown and provided by the Agronomy Department and the
Office of Forage Crops and Diseases, U. S. Department of Agriculture.







Florida Agricultural Experiment Station


BEEF CATTLE BREEDING INVESTIGATIONS
State Project No. 215 A. L. Shealy
Work on this project is conducted at Penney Farms, Florida. The
experimental animals consist of 160 native range cows and one bull each
of the Hereford, Devon, Brahman and Red Polled breeds. The cows were
divided into four lots of 40 each designated as Lots 1, 2, 3, and 4. A pure-
bred Hereford bull was bred to the cows in Lot 1; a purebred Devon bull
to those in Lot 2; a Brahman bull to those in Lot 3; and a purebred Red
Polled bull to those in Lot 4. The calf crop in the spring of 1934 in each
of these lots was satisfactory.
All cows in each lot were graded according to a system of grading for
range cows worked out by Bradford Knapp, Jr., of the United States De-
partment of Agriculture, who is cooperating with the Experiment Station
in all of these studies. The cows were graded in the fall and again in
the spring.
All calves were graded in June 1934 as slaughter calves. All heifer
calves are kept for use in future breeding studies.
This project is conducted strictly under range conditions, since no
supplemental feed is given to the cows and heifer calves. Supplemental
minerals consisting of "salt sick lick", steamed bonemeal, and common
salt were supplied in mineral boxes on the ranges on which each herd was
kept. The mineral consumption by the cattle on the various ranges was
recorded.
This project is in cooperation with Foremost Properties, Inc., and the
Bureau of Animal Industry, U. S. Department of Agriculture.
COOPERATIVE FIELD STUDIES WITH BEEF AND DUAL-PURPOSE
CATTLE
State Project No. 216 A. L. Shealy
Since the native Florida cow is of such importance to the beef cattle
industry in this state, it was deemed wise to begin work with cattlemen
in various parts of the state in which studies would be made with these
animals under actual range or farm conditions. At present work is under
way on 22 farms and ranges over a vast area of the state. Purebred bulls
of the Devon, Red Polled, and Shorthorn breeds were loaned to the cattle
owners on these ranges.
Approximately 40 cows are bred annually to each bull used in this
project. All cows are graded according to a system devised for grading
range cows. The first-cross calves are graded as slaughter calves when
four to five months old. All heifer calves are retained for breeding purposes.
Information is obtained on the age, size, and the time of year calves
and steers are marketed from the ranges and the market price received;
the kind of range on which experimental animals are kept; the number of
acres allowed per animal; the percent of calf crop; and whether or not
mineral supplements are used.
All of these studies are made in cooperation with the Bureau of Animal
Industry, U. S. Department of Agriculture, who own many of the bulls
placed on loan agreement.
DUAL-PURPOSE CATTLE INVESTIGATIONS UNDER FARM
CONDITIONS
State Project No. 217 A. L. Shealy
No work was conducted on this project.
FACTORS AFFECTING THE PERCENTAGE OF CALF CROP AND
SIZES OF CALVES
State Project No. 218 A. L. Shealy
No work was conducted on this project.






Annual Report, 1934


BEEF AND DUAL-PURPOSE CATTLE INVESTIGATIONS
State Project No. 219 A. L. Shealy
Work is conducted at the Main Station, Gainesville; North Florida
Station, Quincy; West Central Florida Station, Brooksville; and the Ever-
glades Station, Belle Glade. Four breeds of beef and dual-purpose cattle
are used in these studies: Herefords at Gainesville, Angus at Quincy, Dev-
ons at Belle Glade, and Red Polled at Brooksville. At each place a herd of
native cows has been provided to be used in definite studies in herd im-
provement work. Opportunity is afforded for comparing native and grade
offspring with purebred animals of the various breeds at these locations.
Birth weights and growth rate on purebred and grade calves of the
various breeds and on native calves are being recorded. All animals are
weighed every 28 days.
The native cows in all the herds were graded in November, 1933, and
again in June, 1934. These grades are recorded and the first cross off-
spring will be graded on the same basis in comparative studies. By using
this system of grading, any improvement in offspring made by using pure-
bred bulls on native cows can be clearly shown.
All calves are graded when three to five months of age as slaughter
or veal calves. The relative importance of the various breeds in producing
calves for slaughter purposes will.be noted as a result of using this grading
system.
Milk production records are obtained in the herds of dual-purpose cattle
at the Everglades Station and the West Central Florida Station.
The work on this project is conducted in cooperation with the Bureau
of Animal Industry, U. S. Department of Agriculture.
INVESTIGATIONS OF HEMORRHAGIC SEPTICEMIA IN CATTLE
AND SWINE
Purnell Project No. 236 D. A. Sanders
Work began in October, 1933. Contact has been established with
veterinarians located in various parts of the state so that experimental
studies may be made of active cases of hemorrhagic septicemia developing
in these different localities. Several strains of organisms have been isolated
from cattle and swine which died following an attack in which symptoms
of hemorrhagic septicemia were manifested. The organisms isolated are
similar culturally and morphologically to the hemorrhagic septicemia group
and all proved virulent for laboratory animals. Studies are made of the
relation of these organisms to the losses encountered.
An organism that is similar culturally and morphologically to the
hemorrhagic septicemia group and that is also pathogenic for laboratory
animals has been isolated from an enlarged hock of a young calf. Obser-
vations are being made on a severe disease showing symptoms of hemor-
rhagic septicemia occurring in a large dairy herd. In this instance 20
animals have become affected, with five deaths. Studies are being made
in this herd in an effort to determine the possible relation of hemorrhagic
septicemia organisms to these losses.
THE DIGESTIBILITY COEFFICIENTS AND FEEDING VALUE OF
DRIED GRAPEFRUIT REFUSE
Purnell Project No. 239 W. M. Neal, R. B. Becker, and P. T. Dix Arnold
Following the palatability trial last year with dried grapefruit refuse,
a byproduct of the canneries, a digestibility trial was conducted with this
product combined with a basal ration of No. 1 Federal graded alfalfa
hay, and 41 percent crude protein grade of cottonseed meal. A trial was
also conducted with the basal ration itself. Each trial was of 30 days'
duration, of which 10 days were preliminary and 20 days experimental.







Florida Agricultural Experiment Station


The highly palatable character of the rations made it possible to secure
complete consumption of the feeds in both trials. Analyses and tabulations
of results are in progress at present. The digestion trials are to be followed
with more detailed studies of the feeding value of this citrus byproduct.
THE EFFICIENCY OF THE TRENCH SILO FOR THE PRESERVATION
OF FORAGE CROPS AS MEASURED BY CHEMICAL MEANS
AND BY THE UTILIZATION OF THE NUTRIENTS
OF THE SILAGE BY CATTLE
State Project No. 241 A. L. Shealy, W. M. Neal and R. B. Becker
Three semi-trench silos of rough 1" by 6" boards were provided. One
was filled with 62,095 pounds of napier grass, another with 88,780 pounds
of Cayana 10 sugarcane, and the third with 100,425 pounds of sorghum, the
cut forage having been weighed when put in the silos.
Thirty steers were used in the feeding trial, the steers consisting of 10
grade Angus, 10 native steers, five grade Shorthorn and five grade Here-
fords. It was impossible to divide these steers into three uniform lots,
since the grade Shorthorn and the grade Hereford steers were not dehorned.
These 10 steers were kept as one lot and were designated as Lot 3. The
20 grade Angus and native steers were-divided into two lots, designated
as Lots 1 and 2, five grade Angus and five natives being placed in each lot.
The steers were given all the silage they would eat during the entire feeding
period. The steers in Lot 1 received napier grass silage; Lot 2, sugarcane
silage, and Lot 3, sorghum silage. The concentrate feed consisted of cotton-
seed meal and ground snapped corn. The same amount of concentrates
was fed the steers in each lot daily.
The sound silage fed was weighed at each feeding, the amount of spoil-
age was weighed as it was removed from the silos, and the silage refused
by the steers was weighed. Samples of the freshly cut forages were taken
for analysis; samples placed in muslin bags in different parts of the silo
were taken as the bags were encountered during the feeding period; and
additional samples of silage were taken at intervals from the end of the
silo as the silage was fed out. Analyses will be made on all these samples
as well as on samples of the concentrate feed which were taken at intervals.
The steers fed on sorghum silage made the greatest daily gain. Sorghum
silage was also found to be the most palatable of the silages studied.
At the close of the feeding period, all steers were graded as beef steers
for slaughter and were sold to a packing plant in Jacksonville. Slaughter
data, including dressing percentage and grade of carcass, were obtained
on each steer.
A COMPARATIVE STUDY OF CORN AND LIQUID MILK, VERSUS A
GRAIN AND MASH RATION IN FEEDING FOR EGG PRODUCTION
State Project No. 244 N. R. Mehrhof and E. F. Stanton
This experiment was started October 15, 1933 at the Florida National
Egg-Laying Contest, Chipley. Two pens of Single Comb White Leghorn
pullets of the same age and breeding and reared under the same conditions
were placed in two houses of similar design. There were 40 pullets in
each pen.
All management practices are the same, with the only difference in the
feed used. Lot 1 receives whole corn and liquid milk, while Lot 2 receives
a grain and mash ration.
Records are kept on feed consumption, feed costs, egg production, mor-
tality, shell texture and value of eggs.






Annual Report, 1934


A COMPARATIVE STUDY OF THE VALUE OF MEAT SCRAPS, FISH
MEAL, AND MILK SOLIDS AS' SOURCES OF PROTEIN
FOR EGG PRODUCTION
State Project No. 245 N. R. Mehrhof and E. F. Stanton
A feeding experiment to compare the value of different sources of
protein for egg production was started October 15, 1933. Four pens of
Single Comb White Leghorn pullets of same age and breeding and reared
under the same management conditions were placed in four houses of
similar design. There were 40 pullets in each pen.
All management practices are the same, the only difference being the
feed used. Each pen received the same basal ration. The basal ration is
supplemented with meat scraps, Lot 1; meat scraps and dried buttermilk,
Lot 2; fish meal, Lot 3; and fish meal and dried buttermilk, Lot 4.
Records are kept on feed consumption, feed costs, egg production, mor-
tality, shell texture, and value of eggs.
LIGHTS VERSUS NO LIGHTS FOR EGG PRODUCTION
State Project No. 246 N. R. Mehrhof and E. F. Stanton
This experiment was started October 15, 1933, to determine the effect
of lights versus no lights on egg production. Two pens of Single Comb
White Leghorn pullets of same age and breeding and reared under same
conditions were placed in two houses of similar design. There were 40
pullets in each lot.
The feed used for both pens was the same. All management practices
were the same except that Lot 1 received artificial illumination in the early
morning, while Lot 2 received no lights.
Records are kept on feed consumption, feed costs, egg production,
mortality, shell texture, and value of eggs.
THE EFFECT OF FEEDING COLON ORGANISMS AND DRIED WHEY
ON THE BACTERIAL FLORA OF BABY CHICKS AFFECTED
WITH PULLORUM DISEASE
State Project No. 250 M. W. Emmel
Previous experimental work has suggested that it may be possible to
influence favorably the colon flora of the intestinal tract of baby chicks
affected with pullorum disease. Results have been obtained to show that
it is apparently more desirable to influence the colon flora by the addition
of 12 percent dried whey to the starting ration than by feeding large num-
bers of colon organisms. Chicks artificially exposed orally to pullorum
disease and fed a commercial baby chick starter to which had been added
12 percent dried whey showed greater net gains and fewer deaths from
this cause than chicks similarly exposed but fed the commercial baby chick
starter feed alone. Chicks fed colon organisms and artificially exposed to
pullorum disease showed greater net gains and fewer deaths than chicks
not fed colon organisms. However, chicks fed colon organisms showed
less net gain and more deaths than comparable groups fed the same com-
mercial starter with the addition of 12 percent dried whey.
Experiments are in progress to determine the percent of dried whey
necessary to influence favorably the colon flora in baby chicks affected
with pullorum disease. Field trials in which 15 percent dried whey has
been added to the regular commercial starter feed have given much promise
of controlling outbreaks of this disease in baby chicks.






46 Florida Agricultural Experiment Station

THE ETIOLOGY OF LEUCOSIS IN THE DOMESTIC FOWL
State Project No. 251 M. W. Emmel
Certain micro-organisms of the paratyphoid and typhoid groups have
been established as the primary cause of leucosis in the domestic fowl.
Typical cases of erythroleucosis and myeloid leucosis have been induced
by the intravenous, intraperitoneal, and intramuscular injections of the
primary etiological agent. Erythroleucosis represents a more severe type
of infection than myeloid leucosis.
Cases of leucosis, properly induced by the injection of certain of the
paratyphoid or typhoid organisms, are transmissible by the intraperitoneal
injection of tissue emulsions of affected organs. Such transmission experi-
ments have been carried through the third generation.
Numerous cases of fowl paralysis have occurred in such transmission
experiments. Fowl paralysis is looked upon as a different manifestation
of the same etiological agent.
COLUMBIA SHEEP PERFORMANCE INVESTIGATION
State Project No. 257 L. 0. Gratz, A. L. Shealy and D. A. Spencer
See report of North Florida Experiment Station.






Annual Report, 1934


CHEMISTRY AND SOILS
The work of the Department has enlarged somewhat during the year
due to a special appropriation of the legislature for a study of the culture
of celery in the Sanford area. Dr. E. R. Purvis, who had formerly held a
fellowship in this Department and since leaving here had received his Ph.D.
degree from Rutgers University, was appointed assistant chemist, stationed
in Sanford.
J. M. Coleman, assistant chemist since 1921, died on February 18, 1934.
In his passing the Department lost a faithful worker and an excellent
analyst.
DIEBACK OF CITRUS
State Project No. 21 B. R. Fudge
See Report of the Citrus Experiment Station.
THE DETERMINATION OF THE EFFECT OF VARYING AMOUNTS
OF POTASH ON THE COMPOSITION AND YIELD AND
QUALITY OF THE CROP
Hatch Project No. 22 R. W. Ruprecht
In the experiment at the Citrus Experiment Station comparing different
amounts of potash the plots receiving 10 percent of potash three times a
year produced the largest yields of both oranges and grapefruit, although
the differences in yield were not very large. For the past several years
the 3 percent potash plots had outyielded the 10 percent plots.
DETERMINATION OF THE FERTILIZER REQUIREMENTS OF
SATSUMA ORANGES
Hatch Project No. 36 R. W. Ruprecht
Work on this project has been discontinued. The results to date indicate
that fall fertilization of satsumas in addition to the spring and summer
applications has a tendency to lessen cold injury in the winter.
DETERMINATION OF THE EFFECT OF VARIOUS POTASH CARRIERS
ON GROWTH, YIELD AND COMPOSITION OF CROPS
Hatch Project No. 37 R. W. Ruprecht
The citrus experiments at the Citrus Experiment Station comparing
sources of potash continue to show a larger yield and a more rapid growth
on the plots receiving potash in the form of low grade sulfate of potash
magnesia than on those receiving potash from other sources used in these
tests.
THE COMPOSITION OF CROPS AS INFLUENCED BY FERTILIZATION
AND SOIL TYPES-PECANS
State Project No. 67 H. W. Winsor
The cooperative fertilizer experiments with the Bureau of Chemistry
and Soils, U. S. D. A., at Baldwin and Jacksonville were continued. Tree
measurements were made and yield records taken. The yield was very
light in both orchards. The heaviest yield at Baldwin was produced with
a 9-3-3 formula with second heaviest yield with a 6-3-6. Yields in the
Jacksonville orchard were too light to draw any conclusions as to the best
fertilizer. The largest increase in growth was produced by a 3-3-9 fertilizer.
The experiments in cooperation with the Horticultural Department were
continued. Fair yields were obtained in some cases. As yet, no increased
yields due to the extra application of nitrogen in July have been found.






Florida Agricultural Experiment Station


EFFECT OF VARIOUS FERTILIZER FORMULAS
State Project No. 94 R. W. Ruprecht
The source of nitrogen test on citrus trees at the Citrus Experiment
Station was continued. The difference in quality and yield between the
plots receiving superphosphate as the source of phosphoric acid and those
receiving this element in the form of steamed bone meal was greater this
year than last year. Sulfate of ammonia with superphosphate produced
the highest yield of pineapple oranges on the plots receiving superphosphate
while the plot having nitrogen in equal parts from nitrate of soda and
sulfate of ammonia with bone meal as the source of phosphoric acid pro-
duced the largest yield on those plots receiving phosphoric acid from the
bone meal. The quality of the fruit was better on all of the plots receiving
bone meal than on those receiving superphosphate, regardless of the source
of nitrogen.
In the Lake Harris experiment the reduction of the phosphoric acid in
the fertilizer has had no detrimental effect on the yield or the quality of
the crop. Likewise, the application of phosphoric acid and potash only
once a year and nitrogen three or four times annually has produced just
as abundant crops as applying all three elements three times annually.
Adverse weather conditions cut down the yield of Irish potatoes to such
an extent that no conclusions could be drawn from the yields obtained.
The tomato experiment at Bradenton was a complete failure, due to
adverse weather conditions.
CONCENTRATED FERTILIZER STUDIES
State Project No. 95 R. W. Ruprecht
In the concentrated fertilizer experiment on citrus at Lake Alfred in
cooperation with the U. S. D. A., the largest yield was obtained from a
mixture composed of Ammophos, ammonium nitrate and sulfate of potash.
At Lake Harris, where mixtures in which urea or sulfate of ammonia
were used as the sole source of nitrogen, the trees do not have as healthy
an appearance as when mixed sources of organic and inorganic nitrogen
were used.
DETERMINATION OF THE EFFECT OF GREEN MANURES ON THE
COMPOSITION OF THE SOIL
Adams Project No. 96 R. M. Barnette
1. Cover Crop Experiments: Analyses of samples collected from dif-
ferent depths of soil of pecan cover crop experiments are in progress.
Samples were collected in 1927 and 1928, and again in 1933 and 1934. The
nitrogen analyses have been completed.
At Monticello on a Norfolk fine sandy loam the nitrogen content of the
surface soil has been increased by planted cover crops of Crotalaria spec-
tabilis in the summer and either vetch, Austrian peas or oats in the winter.
A sparse summer growth of native weeds and no winter cover has barely
maintained the nitrogen content of the surface soil. The nitrogen content
of the lower depths of soil apparently was not affected by the cover cropping
system.
At Gainesville in a pecan orchard the nitrogen content of the surface
soil of Norfolk and Hernando soils was not maintained in an extensive
system of cover cropping using Crotalaria spectabilis in the summer and
vetch or Austrian peas in the winter.
Residual effects of cover crops on the soil are being studied by the
estimation of the quantity of organic matter remaining undecomposed
after being incorporated with the soil for different lengths of time. In
addition, soils screened through a 2 mm. round hole sieve have been cropped







Annual Report, 1934


out in pot experiments with non-leguminous plants to determine the residual
effect of cover cropping systems on the finer portion of the soil. Samples
for these studies have been taken from pecan orchards.
2. Lysimeter Experiments: The chemical analyses of samples during
the course of this five year experiment have been completed. The data
will be compiled for a final report.
3. Small Concrete Plot Studies with Crop Rotation: A winter cover
crop with vetch following a summer cover crop of crotalaria increased the
yield of corn over that of a summer cover crop of crotalaria alone for this
season. The experiment is to be continued.
4. Soil Moisture Studies: The moisture content of the 2-6, 6-10, and
10-14 inch depths of soil growing Crotalaria spectabilis was as a rule lower
than that of the corresponding depths of an adjoining fallow soil. The
surface soil was not as definitely affected by the summer cover crop as were
the lower depths.
The manural value and the residual effects on the soil of Crotalaria
striata, C. spectabilis and C. intermedia have been compared in small
phytometers.
EFFECT OF FERTILIZERS AND SOILS ON THE COMPOSITION OF
TRUCK CROPS
State Project No. 141 J. M. Coleman and R. W. Ruprecht
Work was completed and results presented at the meeting of the
American Chemical Society in March.
A STUDY OF THE DECOMPOSITION OF FOREST, RANGE AND
PASTURE GROWTHS TO FORM SOIL ORGANIC MATTER
Adams Project No. 166 R. M. Barnette
The cooperative agreement with the U. S. Forest Service was terminated
on June 30, 1933. The results of this work have been published in bulletin
265, by Frank Heyward and R. M. Barnette.
A STUDY OF CHLOROSISS" IN CORN PLANTS AND OTHER FIELD
CROP PLANTS
Adams Project No. 220 R. M. Barnette, J. P. Camp and J. D. Warner
Preliminary studies of a chlorosiss" of the corn plant which is locally
called "white bud" have been reported in a paper entitled "A response of
chlorotic corn plants to the application of zinc sulfate to the soil," by R. M.
Barnette and J. D. Warner. This paper will appear in Soil Science. Among
a number of treatments reported in this paper involving the use of the
less abundant elements as well as ordinarily used soil amendments, zinc
sulfate (ZnSO4.7H20) at the rate of 20 pounds per acre in the row in
combination with an inorganic mixed fertilizer made from nitrate of soda,
superphosphate and muriate of potash or with alkaline peat from the Ever-
glades Station produced plants having a healthy growth and produced
grain on soil which otherwise yielded chlorotic or white bud plants with
definitely stunted growth and poor, irregular yields. Stable manure, chicken
manure and leaf mold from a high hammock of mixed pine and hardwood
when applied to the soil gave a healthy and productive growth of the corn
plants.
Ashes of these organic materials were found to contain relatively large
quantities of zinc when tested spectroscopically. Apparently soluble and
available zinc compounds are a specific treatment for the physiological
derangement of the corn plant commonly known as "white bud."
A survey of a number of corn fields during the spring months showed
that "white bud" is widely distributed in the general farming sections of


I






Florida Agricultural Experiment Station


the state. This physiological disturbance of the corn plant is usually
prevalent where continuous culture of the land is practiced. It is not so
abundant where land "resting" is used.
Land "resting" is a system of soil management by which the soil is
permitted to grow up to native weeds and grasses for a year or two and
then put into culture for a year or two, after which it returns to its "rest."
Such a system of soil management has been demonstrated to be a means
of temporarily overcoming the "white bud" condition of corn in experiments
on formerly excessively cultivated lands at the Station farm.
Field experiments testing the use of zinc sulfate as a corrective for
"white bud" of corn as well as a possible plant stimulant have been started
on a number of fields. The results to date indicate that the stand of corn
on lands which produce "white bud" may be effectively maintained by the
use of zinc sulfate. The stimulating effect of zinc compounds on marginal
lands or soils which are on the border line is still unknown.
Field experiments in cooperation with the Agronomy Department have
shown favorable response of a number of agronomic crops to the application
of zinc sulfate to land which formerly produced "white bud" corn. Oats
have responded favorably to applications of zinc sulfate with an increased
yield and earlier maturity. In some instances millet, napier grass, sorghum,
Crotalaria spectabilis, cowpeas and peanuts have shown a stimulation in
growth and a more healthy appearance following the application of zinc
sulfate.
BRONZING OR COPPER LEAF OF CITRUS
State Project No. 223 C. E. Bell and R. W. Ruprecht
In the study of bronzing or copper leaf of citrus, in cooperation with
the U. S. D. A., conducted in a grove located at Lake Wales, the effort
has been unsuccessful to date in changing the soil reaction to the desired
figure even though as high as 3,000 pounds per acre of ground limestone
have been added to some plots.
The bronzed or coppered condition of the trees has largely disappeared
since the more normal rainfall.
THE OCCURRENCE AND BEHAVIOR OF LESS ABUNDANT
ELEMENTS IN SOILS
Adams Project No. 240 H. W. Jones
Applications of zinc sulfate have been found beneficial in overcoming
certain physiological conditions of field crops as well as tung oil and citrus.
The behavior of zinc when added to the soil was studied.
Preliminary work has indicated that considerable amounts of zinc can
be absorbed by the soil, part of which can subsequently be removed by
extraction with water and a further portion by extraction with normal
ammonium chloride.
Preliminary studies have further indicated that zinc when applied to
the soil replaces calcium. Its effect on phosphate and potash are being
studied as well as the possible toxic action if too much zinc is used.
SOIL AND FERTILIZER STUDIES WITH CELERY
State Project No. 252 E. R. Purvis and R. W. Ruprecht
A special appropriation by the Legislature made possible a study of
celery growing in the Sanford area. Preliminary studies this past year
indicate that the soil reaction and the salt concentration of the soil solution
play an important part in the difficulties encountered by the growers.
Applications of some of the less common elements have given indication
that their use may increase the production of celery.






Annual Report, 1934


ENTOMOLOGY
An interesting discovery of the past year was a species of scale,
Margarodes or ground pearl, found to be common on the roots of citrus in
certain sections of the citrus belt, particularly on very light and sandy soil.
It has been located over an area extending from Frostproof north to Fruit-
land Park, and east to Sanford. Heavily infested trees invariably have
an unhealthy appearance but in numerous groves where growers have
suspected this ground pearl of being the cause of the trouble many unthrifty
trees have very few pearls on their roots. It is evident that other factors
are involved and a thorough study will be made to determine how injurious
these pearls are.
They have been found on bermuda grass, maiden cane, in citrus groves
and in newly cleared land where there is no citrus. Mr. Goff at the Lees-
burg Station found them on Centaurea, far removed from any citrus grove.
What may be another species has been found by Dr. E. W. Berger of the
State Plant Board on camphor at Gainesville.
The life history of this scale insect is being studied. It was found that
egg laying began in April and reached its height in early May. The eggs
hatched rather promptly into young crawlers which attached themselves
to citrus roots. How many generations there are in a year is a point which
will be determined.
Their enemies are in process of investigation. Mr. Thompson at the
Lake Alfred Station has found that ants will destroy them. So far no
practical control measures have been developed. This scale-insect is evi-
dently no new thing on citrus, although it has just been discovered.
It was learned at the Citrus Station during the past year that dry wood
termites (Neotermes castaneus) may enter a tree through an old wound
where the wood has started to decay. Tests over a period of 11 months
showed that with some moisture the insects could live on cured oak, pine
and cypress wood, but when no appreciable amount of moisture was present
they perished.
Oak trees blown down by winds were found to have termites working
in them 18 to 20 feet from the base. Good control was obtained by blowing
paris green into the infested holes or tunnels of the roots or trunks.
THE FLORIDA FLOWER THRIPS (FRANKLINIELLA CEPHALICA
BISPINOSA MORGAN)
State Project No. 8 J. R. Watson
Thrips were too scarce in the spring of 1934 for control experiments.
Later in the season they were found to be abundant on Spanish moss and
wild cherry, some of the latter dropping as much as 25 percent of their
foliage as a result of leaf infestation.
Frankliniella williamsi Hood was found infesting corn and cane, and a
heavy infestation of an apparently new variety of F. unicolor Morgan was
found on tuberoses. F. insularis Franklin, hitherto supposed to be confined
to the extreme southern part of the state, was found as far north as Polk
and Pinellas counties.
ROOT-KNOT INVESTIGATIONS
Adams Project No. 12 J. R. Watson
Elimination by Starvation: Carrying out further the work of the pre-
vious year with Crotalaria spectabilis in starving out nematodes from truck
lands, experiments were run to compare the efficiency of crotalaria broad-
cast with that planted in rows and cultivated several times.
It was found at Gainesville that with ample soil moisture during the





Florida Agricultural Experiment Station


early growing season very good control was accomplished by broadcasting
the crotalaria in April and allowing it to grow until October.
However, this method on drier watermelon land at Leesburg was not
so successful due to competing early weed growth and as a result this
land at the end of the summer was found to be about as heavily infested
as on check plots where no effort had been made to eradicate nematodes.
Since frequent cultivation and hand weeding of Crotalaria is quite
expensive, broadcast planting is much cheaper. Apparently the frequent
cultivation of the soil is not necessary for the eradication of nematodes
on moist land when comparatively free of weeds at the time the crotalaria
is sown.
Cyanamid: Experiments several years ago showed that cyanamid when
applied at the rate of about 1,000 pounds per acre very markedly reduced
the amount of root-knot in the soil, but it sometimes reverted to polymeric
compounds which were very poisonous and remained in the soil for months
and even a year.
With the development of a granular type of cyanamid, it seemed de-
sirable to conduct further experiments. No injurious effects were observed
on experimental plots nor on extensive commercial trucking areas which
were kept under observation. Experiments in the past two years, how-
ever, have emphasized the fact that the power of penetration of the
granular material is very poor and to be effective against root-knot it
must be very evenly distributed in the soil to the depth of at least a foot.
When this is done the reduction of the number of nematodes in the soil
is quite marked.
Hosts: An investigation of plants, both wild and cultivated, as to their
susceptibility to root-knot, has been continued. At Leesburg a special
study was made of plants which commonly grow in watermelon fields. It
was found that many of them, including natal grass and "Mexican clover,"
will take root-knot to a certain extent, sufficiently to carry it over from
one season to another.
Extensive observations also have been made on various ornamental
annuals as to their susceptibility to root-knot, a class of plants on which
very little data heretofore had been available.
INTRODUCTION AND PROPAGATION OF BENEFICIAL INSECTS
State Project No. 13 J. R. Watson and W. L. Thompson
Observations were made on the summer and winter host plants of the
recently introduced Chinese ladybeetle, Leis dimidiata var. 15-spilota, a
predatory insect of the citrus aphis. The chief summer foods were found
to be the extra-floral nectaries of Crotalaria striata, supplemented with
pollen of the fireweed, Erechtites, and of the saw-palmetto. It was also
established that the beetles probably will control the papaya whitefly which
is frequently a severe pest.
Paraleptomastix, a parasite of mealybugs which was introduced by the
Experiment Station several years ago, was recovered from the field, indi-
cating that it has become established in the state.
THE LARGER PLANT BUGS
State Project No. 14 H. E. Bratley
Determination of the percentage of parasitization of Nezara viridula
by the feather-legged fly (Trichopoda pennipes) and other tachina flies
was continued. The percentages from July to November were from 25 to
85 percent, the parasite population increasing at a more rapid rate than
that of the bugs.
Leptoglossus phyllopus and Corecoris fuscus were numerous but no
serious injury was noted.






Annual Report, 1934


BEAN JASSID INVESTIGATIONS
Adams Project No. 28 A. N. Tissot
Species Concerned: Observations and collections made during the past
year have confirmed the findings of other years that only one species of
leafhopper is of importance on beans in Florida. The one important species,
Empoasca, fabae Harris, was found throughout the year in the vicinity of
Gainesville, though it varied greatly in abundance at different times. It
occurred in considerable numbers in plantings of cowpeas during the
summer of 1933 and became very abundant in some bean fields during
September, October and early November. During the winter leafhoppers
were present in small numbers on Irish potatoes.
Variety Tests: Further tests were conducted to determine whether or
not there is any variation in different varieties of beans in relation to
jassid infestation and injury. A tract of about two acres on the Experi-
ment Station farm was planted to eight varieties of snap beans, September
14, 1933. Each variety was planted in two of the 16 rows of the tract.
The young beans were attacked by the lesser corn stalk borer, Elasmo-
palpus lignosellus Zeller, and a large proportion of the stand was destroyed.
All varieties were replanted September 30th. Collections of jassids made
over a period of about a month showed considerable variation in the number
of these insects on different varieties of beans at any one time but this
was probably due to the limited size and relatively small number of sam s
taken.
When the entire period is considered there seems to be no significant
difference in the average number of jassids per plant in the different bean
varieties. The adult insects were captured by placing over a section of
row the sampling device described on page 74 of the Annual Report for
1931-1932. The nymph counts were obtained by carefully examining the
individual leaves of five plants of each variety. The average number of
adult jassids per plant varied from 5.5 to 7.3 on the different varieties of
beans. The average number of nymphs per plant varied from 11.1 to 12.7
on the lightest and most heavily infested varieties respectively.
Artificial Control: Experiments of previous years demonstrated rather
conclusively that one of the more thorough methods of combatting the
bean jassid was to spray the plants with sprays containing extracts of
pyrethrum. When these sprays are properly applied it is possible to kill
practically all jassids then on the beans. These sprays, however, are rather
expensive to use and have little or no residual effect so that the beans may
quickly become reinfested if there is a large jassid population in the ad-
joining areas. Bordeaux mixture while usually reducing the jassid popu-
lation is more slow in its action, and under certain conditions appears to be
injurious to the beans.
In the fall of 1933 a new type of dust was tested which proved very
effective against these insects. The dusts used consisted of mixtures of
pyrethrum powders and common dusting sulfur. The pyrethrum powders
used were pure ground pyrethrum flowers containing 0.9 percent of pyre-
thrins I and II; pyrethrum dust A, containing 0.5 percent pyrethrins I and
II; and pyrethrum dust D, containing .05 to .08 percent pyrethrins I and II.
Six different combinations of these powders and sulfur were used. Each
of the first two powders was used at the rate of 1 part of the powder to
19 parts of sulfur and 1 part of the powder to 9 parts of sulfur. Powder D
was used at the rate of 1 part to 3 parts of sulfur and 1 part to 1 part
of sulfur.
The dusts were applied in the open with a blower type of hand duster.
Each of the dust combinations gave almost a complete cleanup of both
adult jassids and nymphs on the beans at the time of dusting. The beans






54 Florida Agricultural Experiment Station

began to show a reinfestation after five or six days but in every case the
number of jassids on the treated plots was far below the number on the
untreated check plots.
In a commercial bean planting of about 20 acres a few miles from
Gainesville the pyrethrum-sulfur dusts were tested on a field scale. Four
different dust combinations were used, each being applied in at least two
different portions of the field. Untreated check plots were left alongside
of each treated plot.
To determine the effectiveness of the various treatments nymphal
counts were made by picking at random a certain number (usually 25) of
trifoliate leaves from each treated plot and its neighboring check plot.
The results obtained in these field tests compared very favorably with
those of the test plots above described.
The combination of pyrethrum powder and sulfur gives promise of
being the most satisfactory and effective method of controlling bean jassids
yet found. The ease and rapidity with which they are applied, the very
complete kill of the insects, and their residual effect which tends to delay
reinfestation recommend them to the bean growers of Florida.
THE GREEN CITRUS APHID
Adams Project No. 60 J. R. Watson and W. L. Thompson
The aphid infestation was very light during the past spring and few
new materials for control were tested. A product derived from pine wood
and a liquid pine tar soap gave promising results as spreaders for nicotine
sulphate. Good control was obtained with a product containing 50 percent
white oil and .33 percent rotenone.
CONTROL OF FRUIT AND NUT CROP INSECTS-INSECTS
AFFECTING PECAN TREES
State Project No. 82 J. R. Watson
Due to the death of Fred W. Walker, who has been conducting this
work at the Pecan Laboratory at Monticello, the work with the leaf and
nut case-bearers has been carried on only in a limited way. Results have
shown the importance of applying the spray material previously recom-
mended as late in the season as possible before the opening of the buds.
CONTROL OF SCALE-INSECTS ON WOODY ORNAMENTALS
State Project No. 157 J. W. Wilson
Activities of the year for the most part were confined to the determina-
tion of the adaptability of the common oil sprays for use on ornamental
plants. The white mineral oils were found to be much less injurious to
many plants than were the red oil emulsions.
INSECT AND OTHER ANIMAL PESTS OF WATERMELONS
State Project No. 162 C. C. Goff
Experiments in the eradication of gophers and salamanders, which are
pests in all cultivated fields, were continued. Effective traps were found
for the "salamander" (ground squirrel), and the "gopher" (burrowing
turtle) was easily disposed of by throwing pieces of corn cob, saturated
with carbon bisulphide, into the burrows, and closing the entrance with soil.
BIOLOGY AND CONTROL OF FIELD MICE IN WATERMELON
PLANTINGS
State Project No. 214 C. C. Goff
Damage by field mice (Peromyscus polionotus) in the vicinity of Lees-
burg was not heavy this past spring, due in part to the poisoning by
growers. It was found that an infestation of a dozen mice per acre would







Annual Report, 1934


destroy as much as 25 percent of the stand of watermelons, and that mice
were more prevalent on old fields allowed to grow up in grass and weeds
than on newly cleared lands.
Some watermelons were destroyed by the cotton rat (Sigmodon).
THE ASPARAGUS CATERPILLAR (LAPHYGMA EXIGUA)
State Project No. 230 J. W. Wilson
Life history studies and experiments with various materials as controls
for this caterpillar were continued at Leesburg.
The life history work has shown that the caterpillars usually become
abundant enough in the ferneries to cause severe damage during the latter
part of May or the first part of June.
From June to October and sometimes later artificial methods of control
must be used to prevent very serious damage. During the fall months of
1933 the weather conditions were such that heavy infestations of the larvae
occurred as late as the second week in December.
Materials used in the tests to control the asparagus caterpillar included
rotenone and pyrethrum compounds, arsenate of lead, calcium arsenate,
sulfur dust, magnesium arsenate, synthetic cryolite, barium and sodium
fluosilicate. Of these materials the undiluted arsenate of lead dust was
the most effective in controlling the asparagus caterpillar. The informa-
tion concerning this insect has been assembled in manuscript form and
submitted for publication.
THE ONION THRIPS (THRIPS TABACI LINDM)
State Project No. 231 J. R. Watson
This thrips has been found on over 100 plants in Florida, the heaviest
infestation occurring on the onion. Cabbage, turnips, collards and mustard
are frequently heavily infested, and onion plantings should be removed
from them as far as possible. Observations have shown that keeping the
onion plantings and surroundings free of all other vegetation markedly
diminishes thrips injury.
THE GLADIOLUS THRIPS (TAENIOTHRIPS GLADIOLI M. & S.)
State Project No. 232 J. R. Watson and J. W. Wilson
During the year this thrips spread rapidly over the state until prac-
tically all counties were infested. Thirteen complete generations have been
reared at Leesburg from August 9, 1933 to June 15, 1934, with two genera-
tions for which the data are not yet complete.
The average duration in days of the various stages for the entire period
August 9, 1933 to June 16, 1934 are as follows: egg stage 5.9, first larval
stage 3.4, second larval stage 2.8, first pupal stage 2.1, second pupal stage
2.7, total for the immature stages 16.8, total length of female life 35.7
days and male life 30.7 days. The average length of the life cycle was
20.6 days.
While the insecticides were being applied it was observed that thrips
jarred from the plants to the surface of the soil died after a few seconds.
The application of a pyrethrum dust containing 0.5 percent pyrethrins
caused the thrips to leap from the plants to the soil surface and when the
sand was hot the thrips soon died.
In a series of tests a rotenone compound gave better control than the
poisoned sirup usually recommended for the control of this insect.
CONTROL OF PURPLE SCALE AND WHITEFLIES WITH
LIME-SULPHUR
State Project No. 233 W. L. Thompson
Refer to report of the Citrus Experiment Station.


I




56 Florida Agricultural Experiment Station

BIOLOGY AND CONTROL OF FLORIDA APHIDS
State Project No. 234 A. N. Tissot
Additions to the Aphid Fauna of Florida: During the past year 101
collections of Florida aphids were recorded. These collections represent
47 different species, three of which have not before been recorded from
the state. These three species Calaphis castanea (Fitch), Aphis nyetalis
H. & F., and Clavigerus smithiae (Monell) were taken on Castanea pumila,
Seneco glabellus, and Salix sp., respectively. These additions now bring
the list of Florida aphids to 115 species. Descriptions of Rhopalosiphum
gnaphalii, Amphorophora crataegi, Macrosiphum mesosphaeri and Tri-
togenaphis eupatorifoliae, heretofore undescribed species, were published
during the year in the Florida Entomologist.
New Host Plants: To the list of known hosts of Florida aphids were
added 16 species of plants. Two of these, the cultivated Shasta daisy,
Chrysanthemum maximum Ram., and another composite Heterotheca sub-
axillaris (Lam.) Britt & Rusby, are new hosts of the citrus aphid, Aphis
spiraecola Patch.
Predators and Parasites: Observations have been made of the predators
and parasites of the citrus aphid in three groves near the University
campus. Whenever aphids were present infested leaves were collected
at intervals of about a week and counts made of the aphids, predators
and parasites.
For a period of about three weeks following the hurricane of September
1933 aphids were extremely scarce in these groves. The predators appar-
ently survived the wind and rain better than did the aphids and were thus
concentrated on the depleted aphid population. Aphids became fairly
abundant in November, but this outbreak was short lived. Due to the
deficiency of rainfall in November and December the citrus trees became
very dormant, quickly reducing the aphid population.
From the first of January to the middle of March it was impossible to
find any aphids in the three groves. Eleven different predators were found
during the past year. Larvae of two species of syrphid flies, Baccha
clavata Fab. and B. lugens Loew., and the adults and larvae of the blood-
red ladybeetle, Cycloneda sanguine Fab., have been present almost con-
tinuously whenever aphids were found.
Larvae of the fly Leucopsis americana Mall. and adults of the two-
spotted ladybeetle Coccinella oculata Fab. were present much of the time,
though not as continuously as the above named species. Syrphus wiede-
manni Johns and the twice-stabbed ladybeetle Chilocorus bivulnerus Muls.
were found only during the winter. The remaining predators were col-
lected only occasionally.
Aphids killed by the hymenopterous parasite Lysiphlebus testaceipes
Cres. and by the fungus Empusa fresenii Nowak. were found most of the
time, though the percentage of aphids thus destroyed varied greatly from
time to time. The fungus has been especially abundant during June of
this year, at one time being responsible for the death of more than 25
percent of the aphid population.
Control: Control experiments were conducted in the laboratory using
the turnip aphid Rhapalosiphum pseudobrassicae (Davis) on leaves of tur-
nips and mustard. Ten different contact insecticides and nine spreaders
were used. A total of 80 different spray combinations were tested. Some
of the materials were standard insecticides while others were newer prod-
ucts, some of them synthetic in nature not yet placed in the general market.
The percentage of aphids killed varied from 23.9 percent to 99.8 percent.







Annual Report, 1934 57

HOME ECONOMICS
Investigations of the Department of Home Economics for the past year
have continued along the lines of human nutrition with special emphasis
on the nutritional value of Florida foods and on the by-products that
might be available from them. Cooperative investigations have been con-
tinued with several departments in the station, the Tennessee School of
Medicine, and with the University of Florida Agricultural Extension
Service.
In cooperation with the latter and the Florida National Egg-Laying
Contest a study has been made of the physical and chemical characteristics
of the eggs from birds fed on different rations. The object of this work
is to determine which characteristics are due to the type of feed and which
are due to heredity, and the effect of the rations on the eggs under storage
conditions.
THE RELATION OF GROWTH TO PHOSPHORUS, CALCIUM, AND
LIPIN METABOLISM AS INFLUENCED BY THE THYMUS
Purnell Project No. 142 C. F. Ahmann
Experiments were continued on thymectomized rabbits to determine the
effect of thymectomy on the size of the litter and the development of the
young. The effects of extirpation, castration, diet and injection of thymus
extracts have been observed. Thymectomized rabbits averaged 85 percent
of the weight of the unoperated litter mates and in no case did a control
animal become sexually mature as young as any of the operated animals.
The offspring of the thymectomized did not make average growth. Cas-
trated rats arid cockerels at maturity had larger thymi than control ani-
mals. Any condition of diet that produced emaciation caused a decrease
in the size of the thymus. The effect of extirpation on the response an
animal makes to antuitrin and the other sex hormones is being studied.
A STUDY OF THE LECITHIN SYNTHESIS IN HENS ON A VITAMIN A
AND LIPOID FREE DIET
Purnell Project No. 198 0. D. Abbott
During the year supplements of yeast, cod liver oil, carotin, lecithin,
xanthophyll, iron, and copper have been added to the skimmed milk-rice
diet in an effort to find a diet that will prevent death of the experimental
birds. On a diet consisting of 30 percent dried skimmilk, 58 percent ground
rice, 10 percent Harris yeast, and 2 percent cod liver oil hens were
in good condition from 4 to 6 months but finally died unless they were put
on a stock feed. The following symptoms were observed: Loss of appetite,
emaciation, crop stasis, and loss of color in comb and wattles. The data
indicate that some as yet undetermined factor is necessary for the nutrition
of hens.
During the first month of the experimental period the hens played regu-
larly and the number of eggs was comparable to those laid by the control
birds. During the succeeding months the experimental birds played fewer
eggs and during the third month laying usually ceased. Analysis of the
eggs for lecithin showed that the eggs from the experimental birds contain
approximately the same amount of lecithin as those from control birds.
Extracts of yeast, liver, egg yolk and thymus are used as supplements
to the rice-milk diet.





58 Florida Agricultural Experiment Station

A STUDY OF THE CHANGES IN THE HEMATOPOIETIC TISSUES OF
RATS ON A VITAMIN A FREE DIET
Purnell Project No. 199 0. D. Abbott
A study has been made of the hematopoietic tissues of rats to determine
whether the blood picture indicates a lowered resistance when the rats are
fed a diet low or lacking in vitamin A over a long period of time. No
significant changes were noted in the number of erythrocytes of leucocytes,
or in the percentage of hemoglobin of rats in the early stages of avita-
minosis. Progressive reduction in blood volume in rats on the deficient
diet would explain the above findings.
In a study of the leucocytes it has been found that there is a decrease
in the lymphocytes and an increase in neutrophiles. In advanced cases of
avitaminosis the neutrophiles show degenerative changes which makes
their classification difficult. Further study will be necessary to interpret
these results.
A STUDY OF THE CHEMICAL COMPOSITION OF THE ASH OF
FLORIDA FRUITS AND VEGETABLES WITH REFERENCE
TO THE MORE UNUSUAL CONSTITUENTS
Purnell Project No. 201 L. W. Gaddum
Qualitative spectrographic analyses of citrus fruits showed the pres-
ence of varying amounts of zinc, copper, manganese, cadmium, aluminum,
boron and tin. Work on the quantitative spectrographic analyses of citrus
fruits (with account taken of variations due to variety, soil type and treat-
ment of tree) are at present in progress.
A STUDY OF THE CHEMICAL PROPERTIES OF THE GLUCOSIDES
OF CITRUS FRUITS
Purnell Project No. 221 L. W. Gaddum
Demand for methods of determining small amounts of the less abundant
materials necessitated the placing of emphasis on Project No. 256. Con-
sequently, work on this project was held in abeyance and confined to the
preparation of samples.
A STUDY OF THE PATHOLOGIC CHANGES IN TISSUES AND
ORGANS OF ANIMALS AFFECTED BY DEFICIENCY
DISEASES OR BY TOXIC SUBSTANCES
Purnell Project No. 222 C. F. Ahmann
Salt Sick: Microscopic studies have been continued on tissues from
animals on control feeding. A part of this material has been put into
manuscript form. Total and differential leucocyte and total erythrocyte
counts have been made on calves on control feeding. The conditions under
which reticulocytes occur in anemic bloods is under study (Project No. 255).
AN INVESTIGATION OF HUMAN DIETARY DEFICIENCIES IN
ALACHUA COUNTY, FLORIDA, WITH SPECIAL REFERENCE
TO NUTRITIONAL ANEMIA IN RELATION TO THE
COMPOSITION OF HOME GROWN FOODS
Purnell Project No. 255 0. D. Abbott, W. M. Neal and O. C. Bryan
Much of the soil of Alachua County is deficient in copper and iron as
measured by chemical analysis of the soil and by the incidence of salt sick
in cattle. Examination of 1,570 school children showed that 42 percent
of them had a hemoglobin below 70 percent. It has also been found that
the children in grades 1 to 3 had a lower hemoglobin than children in the







Annual Report, 1934


higher grades. The anemic condition varied in different sections of the
county.
In one section situated on soils overlying hard rock phosphate subsoils
the anemia was only 3 percent but within a distance of six miles where the
soil is for the greater part Leon flatwoods the percentage of anemia among
the children was 96 percent. Hookworm and malaria are known to con-
tribute to this condition, but it was found that the number of children
infected with these parasites was comparable in the two localities. Soil
samples and vegetables grown on different soil types have been collected
for analysis. A study of families living on different types of soil in the
county is in progress.
THE DEVELOPMENT OF QUANTITATIVE SPECTROGRAPHIC
METHODS IN AGRICULTURAL RESEARCH
Purnell Project No. 256 L. W. Gaddum and R. C. Williamson
A method for the quantitative estimation of zinc in biological materials
has been developed. The internal standard tellurium is employed and the
comparison lines used are tellurium 2147 angstrom units and zinc 2138
angstrom units. By this method 0.005% zinc can be determined in biologic
ashes with an error of about 10 percent. This method will be employed
in a number of cooperative studies on the effect of zinc in Florida crops.
A STUDY OF THE PHYSICAL AND CHEMICAL PROPERTIES OF
EGGS FROM HENS ON EXPERIMENTAL DIETS
Cooperative with Agricultural Extension Service and Florida National
Egg-Laying Contest
O. D. Abbott, Leader
Beginning March 1, 1934, a study has been made of the physical charac-
teristics of eggs from hens on experimental rations at Chipley, Florida.
Fifteen dozen eggs have been examined each week. A part of these eggs
have been stored at different temperatures, preserved in water glass, and
in an atmosphere of carbon dioxide.
The weight, volume, porosity, shell strength, ratio of thick and thin
white, color index and ratio of the diameter to the height of the yolk have
been determined on approximately 1,800 eggs. During the last two months
a study was made of the eggs of individual hens. Special experiments
are in progress on the physical, chemical and cooking properties of thick
and thin whites and on the pH of fresh and stored eggs.
THE EFFECT OF DIET ON THE WORM BURDEN OF CHILDREN
INFECTED WITH NECATOR AMERICANUS AND
ASCARIS LUMBRICOIDES
C. F. Ahmann, Leader
Data obtained have been incorporated in two journal articles, one
appearing in the Journal of the Southern Medical Association and the other
to appear in the Journal of Home Economics.
PALATABILITY AND CANNING STUDIES USING SNOWFLAKE
AND 15/16 SNOWFLAKE CORN
Cooperative with Agronomy Department O. D. Abbott, Leader
A comparison has been made of the table qualities of fresh and canned
Snowflake and of sweet corn of 15/16 Snowflake ancestry. It was found
that 15/16 Snowflake had a sweeter taste and a more creamy consistency
than Snowflake, but that in both the fresh and canned condition the 15/16






60 Florida Agricultural Experiment Station

Snowflake had a pericarp that was decidedly tough. Sixty pints of corn
were canned according to the following method:
270 grams of corn prepared Maryland style and 300 grams of water
were heated to boiling and boiled for 5 minutes. The corn was then trans-
ferred to hot sterile jars. The jars were filled to overflowing with boiling
water and partially sealed. They were placed immediately into a pressure
cooker in which the water was boiling. The pressure was raised to 18
pounds quickly, this required 17 minutes. When the pressure reached 18
pounds it was then allowed to drop back to 12-13 pounds.
The corn was sterilized for 10 minutes, time being counted from the
minute the pressure gauge registered 18 pounds. The sweet corn was a
shade darker in color than the field corn, due apparently to solids suspended
in the medium. All the corn, however, was' light in color and retained
much of the flavor of fresh corn. No spoilage has occurred in any of the
canned corn.







Annual Report, 1934


HORTICULTURE
Probably the outstanding feature of the year in this department was
the further development of the work on zinc on both citrus and tung trees,
with excellent results. Practically all of the large acreages of tung trees
east of Tallahassee were treated with zinc sulphate this year with good
reactions and some citrus groves in central Florida which had been french-
ing badly for several years were brought back into healthy growth with
zinc sprays.
Excellent progress was also made on the cold storage of citrus and the
work on juice was described in an article offered for publication in a trade
journal, which has been accepted and will come out during the summer.
PECAN VARIETY RESPONSE TO DIFFERENT SOIL TYPES,
LOCALITIES, ETC.
State Project No. 46 G. H. Blackmon
Yields for various pecan varieties were, in general, heavier in 1933 than
they were for 1932, but the nut-set has been lighter for 1934 due to un-
favorable climatic conditions and also to the very considerable amount of
storm damage during the fall of 1933. There has been no change in the
relationship of varieties, as regards yield, from the listing in the report
for 1933 with the following exceptions: Heavy crops were produced by the
Bass in Okaloosa County, the Elliot in Walton County, and the Mahan in
Jefferson County.
On the newer varieties studied, the Elliot showed an average diameter
for the nuts of 14/16 of an inch and 53.64% kernel. The kernels were of a
good flavor and had an attractive straw color. The shell broke easily and
released the kernel freely, indicating its value for commercial cracking
plants. Nuts of the Mahan variety were studied further and the following
information obtained:

Diameter of Nuts in I Percent of I Number Percent
16ths of an Inch I Total Number Per Pound Kernel
15 and over .---....-.......--..... 34.0 40 59.58
13 and under 15 ..-.....- .... 36.0 43 56.78
Cracking* stock ................ 30.0 49 56.28
Off shape and size.
Studies were continued on the use of zinc sulfate as a corrective for
pecan rosette following the preliminary tests in 1933. Curtis trees which
have been severely rosetted as a result of lime applications to the soil about
18 years ago showed some response to soil applications of two pounds of
89% zinc sulfate per tree, though one-half pound per tree failed to produce
appreciable results during the first year of the experiments. In other trials
also applications of one-half to one pound per tree failed to produce results
where applications of two pounds or more brought favorable response.
In some cases no response at all was made to zinc sulfate when applied
to the soil and, in other instances an irregular response. Experiments
were started with zinc sulfate in sprays on some of these badly rosetted
trees and these seem to show the possibility of better results than have
been obtained by soil treatments. This work will be continued.
The form of pecan rosette commonly known as "mouse-eared leaf" has
been corrected by means of an application of five pounds per tree in 1933,
followed by a second application in 1934. Many of the leaves on the tree
are now of normal size and this would seem to identify this disease defin-
itely as a form of rosette.







Florida Agricultural Experiment Station


COOPERATIVE FERTILIZER TESTS IN PECAN ORCHARDS
State Project No. 47 G. H. Blackmon
Results of the work on this project for the last several years have been
brought together in bulletin form and submitted for publication. The
results show a considerable difference in the response of different varieties
to fertilizer treatment and that consequently some varieties may be fer-
tilized profitably, but with other varieties the use of any considerable
amount is questionable.
Considerable injury in some of the experimental plots was due to the
storm in September, 1933, particularly in Bradford and Duval counties,
and this resulted in a very light bloom in 1934. In Jefferson County a
great deal of injury came from the nut case-bearer which destroyed 30
or 40 percent of the nuts and the yield of all plots in that county will be
light, with the exception of those of the Moore variety. The yields for
1933 showed a consistent superiority of fertilized trees as compared with
unfertilized trees.
VARIETY AND STOCK TESTS OF PECAN AND WALNUT TREES
State Project No. 48 G. H. Blackmon
The test orchard improved in condition considerably during 1933 with
several varieties having a small crop of nuts and in 1934 many trees have
set a fair to good crop and most of them have shown vigorous twig growth.
Due to the appearance of rosette in some of the trees, zinc sulfate was
applied both to the soil and to the trees as a spray. Practically no Crota-
laria spectabilis was produced during 1933, but the grass crop was heavy.
Rosette, similar to that in pecans, made its appearance in the seedling
Black Walnut trees during 1933. Zinc sulfate was applied to the soil
around some of the trees in June of that year, and in August some were
sprayed. Those receiving half a pound per tree, applied to the soil, began
to show a marked recovery in 30 to 40 days. Though the trees are set
10 x 10 feet, checks adjacent to trees receiving soil treatment are rosetting
badly, whereas the treated trees have recovered their normal habit of
growth.
The cold storage work on pecan nuts and nut meats was continued as
previously outlined. In pecan kernel tests both vacuum and nitrogen packs
at a temperature of 32 showed up well.
PROPAGATION, PLANTING AND FERTILIZING TESTS WITH
TUNG-OIL TREES
Hatch Project No. 50 A. F. Camp
In the fertilizer test on tung-oil at the Experiment Station, the trees
receiving no fertilizer continue to give the lowest yields, whereas the plot
receiving a 5-8-4, mixed nitrogen, gives the best results. The amounts of
fertilizer per tree have been increased to six pounds in two applications,
with the exception of Plot 6, which receives 20 pounds of stable manure.
In this block the 1934 spring bloom was slightly later than usual but very
good, and no cold damage occurred during the blooming period so that a
good crop is in prospect for 1934.
The fertilizer test near LaCrosse is not as yet far enough along to draw
any very definite conclusions. All of the crop set in the spring of 1933
was removed to give the trees an opportunity to grow as much as possible.
Some work on zinc sulfate has been done in these plots and has shown
excellent results where bronzing was apparent. The use of chicken manure
as a fertilizer is still giving outstanding results and this is probably the
best plot in the entire experiment. A crop set for 1934 but most of it







Annual Report, 1934


was knocked off or badly damaged by a very severe hailstorm which had
the effect of setting back the progress considerably, as the trees were very
severely injured and much bark was hammered from the limbs and trunks.
Following up the experiments on propagation of tung-oil, some piece
root-grafts were made, using the whip-graft method. These have been
planted out in the nursery and at present about 75% are alive but most
have made poor growth, though the union between stock and scion calloused
over well, in the majority of cases.
In the spring of 1933 a large number of crosses were made and, in most
of these, the cluster type was used as a female parent and the No. 9 tree
as the male parent. The seeds resulting from these crosses have been
planted in the field and will be kept under observation. This combination,
it is hoped, will give a superior variety both as to growth and bearing habit.
A considerable number of flowers of each of these were also close-pollinated
as the preliminary step in obtaining a pure line of each of these varieties.
It is believed that if propagation by budding or grafting fails commer-
cially the future of the tung-oil industry will, to a very considerable extent,
depend upon pure line strains of high yielding varieties and, so soon as
these strains have been developed by hand pollination, plantings should
be made in isolated areas for the providing of pure line seed for the future.
Zinc sulfate continued to show excellent results in correcting bronzing
in large tung-oil plantings and practically all of the plantings of any size
east of Tallahassee have been treated with this material. The information
to date on this subject has been brought together in a manuscript, which
will be offered for publication in the near future. Detail of work on zinc
salts will be found under Project 238.
The experiment laid out near Lake City, in which budded trees were
to be compared with seedling trees, produced a light crop in 1933 but it
was not sufficiently large to allow the drawing of any conclusions. This
plot has been utilized as a zinc sulfate experiment, however, with excellent
results, and the trees which were in bad shape from bronzing when treated
two years ago are now in good condition while the checks are in bad con-
dition. The zinc test was laid out across the rows of budded and seedling
trees, so that the experiment can be continued with its original purpose
in view.
TESTING OF NATIVE AND INTRODUCED SHRUBS AND
ORNAMENTALS, AND METHODS FOR THEIR PROPAGATION
Hatch Project No. 52 A. F. Camp and G. H. Blackmon
The following plant introductions have been under observation under
field conditions for some time. The listing given below gives the relative
adaptation of these plants to conditions of climate and soil found at
Gainesville.
Thrifty Growth
FPI No. 70973 Cornus sp.
FPI No. 56302 Cornus capitata
FPI No. 64762 Elaeagnus philippensis (subject to cold injury)
FPI No. 33500 Jasminum Beesianum (does not bloom)
FPI No. 55484 Juniperus procera
Fair Growth
FPI No. 66923 Jasminum heterophyllum
FPI No. 76927 Phillyrea latifolia
Unthrifty Growth
FPI No. 88935 Argania spinosa
FPI No. 57080 Juniperus cedrus


0







Florida Agricultural Experiment Station


Seeds of Ilex paraguariensis (FPI No. 105,222) have been planted and
the percentage of germination found to be very low. Out of several hun-
dred seed which were planted only two plants were obtained, after a 7 to 9
months' germination period. As the seed coat is very hard, it was thought
that treatment with sulphuric acid at varying strengths and lengths of
time might be helpful in increasing the percentage of germination. This
has been done. Sufficient time has not elapsed since to determine the effect.
COVER-CROP TESTS IN PECAN ORCHARDS
State Project No. 80 G. H. Blackmon
In the cover-crop experiments in Jefferson County the tonnage of green
material produced by both summer and winter cover-crops was compara-
tively light, due to the sparse rainfall. In yield of nuts and growth of tree
the Frotscher continues to respond better than the Stuart.
No decisive differences were shown in the size or character of the nuts
due to variation in treatment. The 1934 bloom was heavy in both Frotscher
and Stuart varieties and the set was good. There has been a loss of about
30 percent in the crop due to nut case-bearer but the prospects are for a
better crop than in 1933.
In the plots at Gainesville Crotalaria spectabilis produced a great deal
more green material than did winter cover-crops, in some cases 10 times
as much.
PHENOLOGICAL STUDIES ON TRUCK CROPS IN FLORIDA
State Project No. 110 M. R. Ensign
Work on this project had to be suspended due to the resignation of Mr.
Ensign. Most of the results of the work to date had been put in manu-
scripts, and one was submitted for publication. The field plots were
harvested by other members of the staff but the data have not been studied
and compiled for publication but will be turned over to Dr. Jamison who
will succeed Mr. Ensign in truck crop work.
The photoperiodism work with potatoes was continued and the out-
standing result was the superior performance under the Florida day length
of seedling No. 41914 as compared with other varieties under test. The
newer varieties, such as the one mentioned above and Katahdin and
Chippewa, apparently showed less definite adaptation to the northern day
length than did the Spaulding Rose and thus probably offer more possi-
bilities for future development in potato breeding.
FUNDAMENTAL PHYSIOLOGY OF FRUIT PRODUCTION
State Project No. 111 A. F. Camp
In the cultural experiments with citrus the mulched trees continue to
show an advantage over unmulched. The foliage is greener and the
growth more vigorous but the fruit seems to be showing signs of coarse-
ness. During the coming season, it will be possible to make a comparison
of the fruit in the various plots to determine the effect of the cultural
treatments. Of the other plots, the trees in the plowed plot look a little
the best and the uncultivated plot a little the worst, though there is very
slight difference in any of the plots so far and it will take two or three
years more to develop definite information.
Mr. Richard Brooks completed a study on the effect of the rootstock on
the character of the fruit. Trees of the same age and growing side by
side at the Citrus Experiment Station at Lake Alfred were used in this
experiment. The sour orange stock was found to increase the percent of
juice, acid and sugar in the fruit and the specific gravity of both the juice
and the whole fruit. The rough lemon stock increased the size of the fruit







Annual Report, 1984


and the thickness and percent of peel in both oranges and grapefruit. The
differences were small but the trends were definite. This work was com-
piled in thesis form and submitted in partial fulfillment of the requirements
for a Master's Degree.
AVOCADO MATURITY STUDIES
Purnell Project No. 139 A. L. Stahl
Work on the systematic study of the composition of avocados in relation
to maturity was completed and the project discontinued.
During the past year some analyses of avocados have been carried out
for growers to aid them in marketing problems.
RELATION OF NITROGEN ABSORPTION TO FOOD STORAGE AND
GROWTH IN PECANS
Adams Project No. 165 G. H. Blackmon and A. F. Camp
Further trials of pecan seedlings in water cultures without aeration
gave very poor results, as none made a satisfactory growth. Boron, zinc,
manganese, and copper were added to the cultures and the growth com-
pared with the development of the seedlings where no additions were made.
The seedlings again responded readily to the additions of boron at the rate
of % p.p.m., but since the pecan roots could not develop satisfactorily in
water cultures without aeration, normal growth was not made.
Pecan seedlings were grown to almost normal size in water cultures
which were aerated, five-gallon Pyrex bottles having been used for con-
tainers. However, there was not the marked difference in growth due to
boron additions that was obtained in the unaerated water cultures and in
sand. One of the plants growing in the aerated solution, without boron,
began to show a splotching in the leaves during May, while the one that
received boron continued to show up well, though the leaves did not have
as dark green color June 30 as they should.
Sand cultures proved to be much more satisfactory for the growing of
pecan seedlings than water cultures. The growth in sand cultures, using
a favorable nutrient solution, was comparable after one year to that ob-
tained in the nursery in a similar length of time.
Boron applied at the rate of p.p.m. as boric acid to the culture
solution gave better results than the straight nutrient solution or the
nutrient solution with zinc salts added, but additions of zinc gave better
results except in one instance than did the check to which neither boron
nor zinc had been added.
The solution giving the best results contained the following concentra-
tion of nutrients expressed in parts per million: NO., 305.0; PO4, 601.5;
K, 325.7; Ca, 58.5; Mg, 288.0; SO4, 1138; with boron added as boric acid
at the rate of % p.p.m. The boron was added to the cultures along with
the culture solution, and iron was added weekly.
VARIETY TESTS OF MINOR FRUITS AND ORNAMENTALS
State Project No. 187 A. F. Camp and H. S. Wolfe
Avocados: The late spring frosts of March and April at Gainesville
killed the bloom, thus completely destroying this year's crop of fruit.
During the winter these trees were subjected to a temperature (official)
of 27* F. the night of January 31, and 28 F. the night of February 1; un-
officially, the temperature was reported as low as 25' F. Only a slight
amount of leaf damage was evidenced in two trees as a result of the cold.
Seedling Mexican avocados have been budded with scions from the
three trees showing the most desirable fruit characters, including size,






Florida Agricultural Experiment Station


flavor and time of ripening. These will be planted out for further ob-
servation.
Blackberries: Both Strains 1 and 2 of the Advance blackberry produced
a good crop of fruit this year. The Youngberry for the second year in
succession bore a very small crop of fruit, and showed a light infection
of the double-blossom disease. The Marvel blackberry, despite the fact
that all of the plants were infected with the double-blossom disease, pro-
duced well. The Kosmo berry and Nessberry Nos. 2, 4, 6, 7, 8 and 9 made
very poor growth and produced no marketable fruit.
Grapes: The younger plants of the variety Beacon have set a good
crop of fruit this year. The variety Extra has also set a good crop. Zinc
sulfate has been applied to the soil around some of the plants and one row
was sprayed with a zinc sulfate and lime spray. Sufficient time has not
elapsed since these treatments were made to be able to determine the
value of the materials.
This report covers former Hatch Projects Numbers 49, 51, 58, 59, and 81.
STUDY ON THE PRESERVATION OF CITRUS JUICES AND PULPS
State Project No. 189 A. F. Camp
This project was not carried on very extensively during the past year,
owing to the pressure of other work, but the studies on the cold storage
of orange juice were completed and a manuscript was submitted for pub-
lication in a trade journal.
COLD STORAGE STUDIES OF CITRUS FRUITS
Purnell Project No. 190 A. F. Camp and A. L. Stahl
Studies on the effects of various wrappers on the keeping of citrus
fruit while in cold storage were continued and several new types of moisture-
retentive wraps made from cellulose derivatives were added to the list.
Over a hundred boxes of fruit were used in these experiments. As a result
of these and preceding experiments the superiority of moisture-proof
wrappers in maintaining weight and preserving the general appearance
of the fruit has been established. Loss in weight and pitting have been
found to be the most important factors in reducing the salability of the
fruit and for overcoming these two factors the moisture-retentive wrappers
show definite superiority. For fruit wrapped in such wrappers the optimum
storage temperature was found to be about 370 F. whereas for wrappers
nonretentive to moisture the best temperature was about 42" F.
The expense of such wrappers has been a barrier to their use and
studies have been made with a view to reducing this cost and still retaining
the benefits to be derived. Large bags which would fit the half of an
orange box and allow sufficient top for folding over were made from the
various suitable moistureproof materials and used as box liners. These
were as successful as single fruit wraps in keeping down both pitting and
moisture loss. The combination of tissue wraps and moistureproof liner
proved very satisfactory. The only drawback to such a procedure is "nest-
ing" of decayed fruit, which is prevented by the individual wrapper.
Continuing the work on the prevention of pitting, over 50 dips or coat-
ings for fruit were studied. On a basis of prevention of moisture loss and
pitting and the retention of good appearance, the outstanding treatments
were a colloidal paraffin, a commercial emulsion using carnauba wax as a
base, cedar oil and turpentine. Both oranges and grapefruit were held
four months in good condition at 37o and 420 F. when treated with any
of these four treatments. The colloidal paraffin showed up to the best
advantage as far as keeping quality was concerned but was slow in drying
and less desirable for commercial use.







Annual Report, 193.4 67

Work on the use of gases in fruit storage was continued and the pre-
liminary results obtained last year were confirmed. Carbon dioxide con-
tinued to be the only gas causing soggy breakdown and both air and
nitrogen continued to be superior to either oxygen or hydrogen in keeping
fruit in good condition in gas-tight cylinders. Work has been started on
an application of this to commercial storage.
In a commercial storage experiment started in the spring of 1933
Valencias wrapped in cellophane kept well and were sold locally during
the latter half of July, August and the early part of September. Acceptance
by storekeepers was slow at first due to former disastrous experiences with
stored fruit. Later in the summer the demand exceeded the supply and
no difficulty was experienced in disposing of the fruit in competition with
California oranges.
An interesting development occurred during the last year as the result
of an attempt to keep down stem-end rot, which continues to be an out-
standing problem in fruit storage. Fruits for some of the experiments
were treated as picked by disinfecting the freshly cut stem end with 95%
alcohol. This treatment either prevented stem-end rot entirely or reduced
it to such an extent as to render it negligible.
CITRUS MATURITY STUDIES
Purnell Project No. 237 A. L. Stahl
This is a new project which will assume the work on the maturity of
citrus fruits formerly carried by Project 139 on that of avocados. The
study of the development of citrus fruits from bloom to maturity and the
effect of various cultural and chemical treatments is under way.
To get an idea as to the variation in the physical and chemical charac-
teristics of citrus from the same tree, a thousand fruits from one orange
tree were taken and a complete physical and chemical analysis made upon
each. The sampling was done over a period of a few weeks so that all of
the fruits were practically of the same age. Due to the large amount of
samples, the chemical analysis has not yet been completed. Many inter-
esting and useful results have been obtained and it will now be possible
in any of the following maturity work to judge whether the analytical
figures are significant or fall within the range of variation in individual
fruits.
A systematic study of citrus fruits from bloom to maturity has been
started, from which methods for determining ripeness may be developed.
During the blooming season thousands of fruits were marked as to the date
of setting and these are sampled and analyzed at regular intervals, with
the exact age of the fruit known. Both grapefruit and oranges have been
obtained from Bradenton, Cocoa, Lake Alfred and Gainesville. Morpho-
logical and physiological studies are under way on the principal varieties
of each section.
STUDIES ON THE EFFECT OF ZINC AND OTHER UNUSUAL
MINERAL SUPPLEMENTS ON THE GROWTH OF
HORTICULTURAL CROPS
Purnell Project No. 238 A. F. Camp
Use of zinc salts on tung trees was continued under this project. Prac-
tically all of the large groves in the north central section of Florida have
been treated with excellent results except in one grove, parts of which
have failed to show a satisfactory response. The experimental work has
indicated that on the soil types on which tung trees are ordinarily planted,
applications of one-fourth pound per year are insufficient to bring about
rapid recovery from bronzing, whereas half-pound applications made dur-







Florida Agricultural Experiment Station


ing the spring and early summer have brought immediate response in nearly
all instances.
While there was a marked difference in response as between one-fourth
and one-half pound applications there was distinctly less between one-half
and one or two-pound ones, though the larger gave a little more rapid
results. It is possible that small applications over a series of years may
bring bronzed trees back into condition, but for rapid recovery larger
amounts seem to be indicated.
Comparisons between the ring and broadcast methods of application
showed little difference, though there may have been a slight margin in
favor of the latter. Applications of zinc sulfate mixed with acid phosphate
and other materials that might be expected to tie up the zinc in an insoluble
form gave excellent results when the mixture was held for a weelt or less
before applying. Longer standing of the mixture might result in an un-
favorable reaction and this will have to be studied more in detail.
Experiments carried on through the season of 1933 showed that excel-
lent results could be obtained by spraying the trees with a mixture of
zinc sulfate and hydrated lime. Zinc sulfate and water injured the trees
too badly to be useful but a spray mixture containing 5 pounds of 89%
zinc sulfate and 21/ pounds of hydrated lime to 50 gallons of water was
found to be satisfactory. Trees sprayed from one to five times during the
1933 season grew splendidly and bronzing disappeared.
However, when these sprays were omitted on these trees the following
year bronzing began to show up early in the summer. If sprays are used
they will probably have to be repeated every year. Spraying experiments
were not carried on very extensively in 1933 since it was believed that soil
treatments would meet the needs of tung trees satisfactorily. There is
some evidence, however, that sprays may be necessary on certain soils and
the plans have been considerably expanded during the current season.
The use of zinc salts to correct frenching in citrus has continued to
give excellent results. The Satsuma orange trees in which frenching was
corrected last year with zinc sulfate applications to the soil have grown
splendidly and put on a good crop of fruit. The untreated trees lost almost
all of their leaves during the winter cold, have been badly frenched during
the entire season and the crop is negligible. In spite of the fact that the
trees had never grown well before the treatment they now appear to be
equal in color and growth to Satsuma trees growing on soil to which they
are adapted.
In experiments on the very sandy soils in Polk and Highlands counties
the results from zinc sprays have been outstanding. Groves that had been
frenched and dying back badly for several years were brought into good
growth within four or five weeks with spray applications during the spring
and early summer, and have shown an astounding recovery. Frenching
has disappeared and the foliage has taken on a deep green color and even
leaves that were frenched at the time of the application have regained
their green color though they have not grown in size. At the same time
the trees have set fruit and apparently are developing it normally.
The sprays used in most of the experiments were made up of zinc sul-
fate (89%) and hydrated lime; a combination of 5 pounds of zinc sulfate,
2% pounds of hydrated lime, 50 gallons of water and calcium caseinate
spreader gave excellent results and was most generally used. Sprays con-
taining less than two pounds of zinc sulfate to 50 gallons of water did not
give as good results as higher concentrations. The addition of zinc sulfate
to lime-sulfur sprays brought splendid reactions though the toxicity of the
spray to insects may have been reduced due to the throwing down of sulfur.
Zinc sulfate without lime had a splendid outcome and usually there was








Annual Report, 1934


no burning if the amount used did not exceed 5 pounds to 100 gallons of
water. Favorable response also has been obtained when zinc sulfate and
the necessary extra lime were added to bordeaux sprays.
Results from soil treatments have been much more irregular than has
been the case with tung trees. In some cases no visible result was obtained
from soil applications, whereas in others application of from five to 15
pounds per tree broadcast brought good response. Applications ranging
from one-fourth to two pounds as used for tung-oil and Satsumas in the
vicinity of Gainesville gave little or no benefit, while excellent reactions
were obtained from the use of sprays. Whether the zinc salt is leached out
of the very sandy soils too quickly or is tied up by something in the soil
remains to be determined. So far sprays seem to be much more sure and
effective than soil applications for citrus.
An extensive series of experiments with truck crops was carried out
on the Experiment Station grounds at Gainesville, on soil similar to that
on which tung oil, Satsumas and pecans had shown a response to zinc salts.
No favorable reaction could be detected but the soil had "laid out" for
several years and there is evidence that when this has happened there
is no result from zinc treatments on the first crop grown. These experi-
ments will be continued on the same soil.
FUMIGATION RESEARCH
R. J. Wilmot, Leader
Apparatus to generate HCN from sodium cyanide and sulfuric acid
outside the fumigation boxes at Port Tampa and Key West was installed
and tested and dosage schedules worked out. These generators were so
designed as to give a maximum evolution of gas with ease and safety of
manipulation, and at the same time gave control at all stages of generation.
They embodied the ideas of several other workers in this field.
At the request of the State Plant Board a series of experiments were
run on scale-infested grapefruit to determine whether or not fumigation
with hydrocyanic acid gas would kill all the scale on them, particularly
those around the button. Concentrations ranging from 0.14% HCN to
0.44% gave 100% control of purple scale, Lepidosaphes beckii (Newm),
in one hour at 90 F. without injury to the fruit.
In experiments using the pea weevils, Mylabris (Bruchus) quadrimacu-
latus and M. pisorum, it was found that although a 100% kill of M. quadri-
maculatus was reached with an hour exposure to gas at a concentration of
0.24% at 96" F., only 70.5% of M. pisorum were killed. At 97" F. and two
hours exposure 0.49% would kill M. pisorum but 0.86% concentration was
required for a one-hour exposure.
A large scale experiment on the rearing and fumigation of the cigarette
beetle, Lasiodenra serricorne (Fab.), is under way and incomplete results
show that the adult stage of this insect is quite resistant to hydrocyanic
acid gas, requiring a concentration of 1.02% for 100% kill in one hour at
74" F., 0.62% for 100% kill in two hours at 86 F. and a concentration of
0.92% for 100% kill in one hour at 96* F. Freshly emerged adults, one
to four days old, were found to be most resistant to hydrocyanic acid gas.







Florida Agricultural Experiment Station


PLANT PATHOLOGY
Research activities of the department, have been centered on 25 plant
disease projects. Four of these were initiated during the year and, con-
sequently, only a limited amount of information has been obtained on them.
Work on two projects has been completed and information obtained is under
preparation for publication. Because of economic conditions, a greater
portion of effort has been directed toward determining the cause of dis-
eases and developing economical methods of control. Progress made upon
the various projects is reported under the project numbers, but some of
the more important results may be referred to here.
In addition to research on important disease problems of major crops,
the department has been called upon to render an unusual amount of service
directly to the agricultural interests of the state in combatting local situa-
tions and in identifying and giving information on economic and poisonous
plants, weeds, trees and shrubs, through both correspondence and personal
contact.
Results obtained from spraying experiments for control of citrus scab
have shown that when the disease is held in check one year with bordeaux-
oil emulsion, it may be commercially controlled the following year with
lime-sulfur plus bentonite sulfur. Where infection was severe and not
controlled with bordeaux the preceding year, none of the sulfur compounds
would control it.
Two new diseases of potatoes occurred in the Hastings area this season.
A seedpiece decay due to a species of Fusarium caused an average of 25
percent reduction in stand on 400 acres. A stem rot caused by Sclerotinia
sclerotiorum was generally distributed in the section, epidemic in a few
fields, causing as high as 50 percent infection of the stems and 14 percent
reduction in yield.
Treating soil with sulfur one year and with lime the following year
practically eliminated the loss in potato tuber decay due to Bacterium
solanacearum.
Cross inoculations with species of Diplodia from sweet potatoes, citrus
and cotton have demonstrated that all cause rots of these crops that are
similar to the rots due to Diplodia frumenti, the species causing an ear
rot of corn. Studies will be continued, to determine whether all belong to
the same species.
No parasitic organism has been obtained from "rusted" Asparagus
plumosus plants that will produce typical symptoms of the disease when
healthy plants have been inoculated with pure cultures. Likewise no environ-
mental factors have been found responsible for the conditions. It appears
that a combination of environmental factors and weak parasitic organisms
produce the rust.
Field trials with numerous selections of watermelons have demon-
strated that at least two lines have uniform type and quality of melon
combined with resistance to Fusarium wilt. The quality of the melons is
superior to that of commercial varieties grown for shipping in the state,
and they are ready to test on a commercial scale.
In trials of selections of tomatoes for resistance to Fusarium wilt,
certain progenies proved superior to any of the parent varieties. Trials
of the progeny of a plant discovered two years ago show that it breeds
true to type and is apparently a new variety.
Experiments for the control of black or Phoma spot of tomatoes have
confirmed results obtained during the previous two years, that the disease
can be controlled by spraying the plants in the field and washing the fruits
in a fungicide immediately after they are picked.
It has been determined that a bark disease of young Tahiti lime trees







Annual Report, 1934


in the nursery and grove is caused by Diplodia natalensis and Phomopsis
citri, two fungus organisms prevalent in citrus groves.
During the year more than 1,000 specimens of fungi and diseased plants
have been received and examined for residents of the state and, where no
information was available in bulletins, letters were written. Also, numerous
identifications have been made of herbs, shrubs and trees, cultivated and
wild.
About 500 diseased plant specimens have been diagnosed for the State
Plant Board. Also, a large number of insect host plants collected by
nursery and port inspectors have been identified.
The value of the herbarium has been increased greatly during the year.
With the aid of a student paid from F.E.R.A. funds, the 4,956 plant speci-
mens contained in the Cuthbert collection have been mounted and labeled.
Over 3,000 sheets of other specimens collected during the past five years
have been mounted and about half of these have been distributed in the
cabinets.
CITRUS DISEASE PROJECTS
Three projects on citrus diseases, under the supervision of this depart-
ment, are being conducted at the Citrus Experiment Station and are re-
ported with its work. These projects are No. 3, melanose of citrus and
its control; No. 24, citrus scab and its control; and No. 185, investigation
of stem-end rot of citrus fruits caused by Phomopsis citri Faw.
DOWNY MILDEW OF CUCURBITS
Adams Project No. 19 G. F. Weber
Work on this project has been confined to a study of the effects of
bordeaux spray on the set of fruit on cucumber plants. Half of the 132
plants growing in a plot were sprayed weekly with 2-3-50 bordeaux and
half were not sprayed. Counts were made daily of the pistillate and
staminate flowers developing on each plant and, as the fruit set, they were
counted and removed from the plants. Sprayed plants produced an average
of 1199.37 staminate flowers, 155.36 pistillate flowers and 124 set fruit
per plant, while the non-sprayed plants produced an average of 1262.48
staminate flowers, 173.33 pistillate flowers and 115.56 set fruit per plant.
The lower set of fruit on the non-sprayed plants may be due to the fact
that downy mildew was present and gradually reduced the functioning
leaf area until the plants were practically killed. The disease first appeared
on the check plants one month after. the seed were planted and gradually
spread and almost completely killed them within six weeks.
NAILHEAD SPOT OF TOMATOES
Adams Project No. 116 G. F. Weber
This year's experimental work consisted chiefly in determining and
verifying the host range of the fungus on native and cultivated plants.
A manuscript covering the experimental work contained in the various
annual reports has been prepared and constitutes a final report on the
completed project.
INVESTIGATIONS RELATIVE TO CERTAIN DISEASES OF STRAW-
BERRIES OF IMPORTANCE TO FLORIDA
State Project No. 126 A. N. Brooks and R. E. Nolen
RHIZOCTONIA BUD ROT
Inoculation experiments show that the development of this disease is
favored by: (1) Abundant soil moisture and high relative humidity; (2)
Presence in the top soil of large amounts of organic matter; and (3) Com-







Florida Agricultural Experiment Station


paratively low temperatures, average daily mean temperatures below 75" F.
The original isolate, which is practically identical with Rhizoctonia
solani, was found to be the only one capable of producing bud rot. The
crown parts of the plant are readily attacked but the rhizome and roots
are not. The bud rot fungus will attack the seedling stage of beans, beet,
cabbage, carrot, cucumber, eggplant, mustard, okra, turnip, and Crotalaria
spectabilis, as has been demonstrated by inoculation experiments. Pea, pep-
per, spinach (New Zealand), squash, and tomato were not readily attacked.
SCLEROTIUM BLIGHT
Tests have been inaugurated to reduce the injury from this disease.
Infection occurs more quickly and is often more severe in the presence
of organic matter. Infected berries were found in more fields than here-
tofore.
DIPLODIA ROOT ROT
This disease was not abundant during the past year. No fruiting stage
of this fungus has been found on the plants. It attacks newly set plants
in a very few days, but plants with large established root systems are
more resistant to it.
STUDIES RELATIVE TO DISEASE CONTROL OF WHITE
(IRISH) POTATOES
State Project No. 130 A. H. Eddins
Sclerotinia rot or stem rot caused by Sclerotinia sclerotiorum was gen-
erally distributed throughout the Hastings section and was epidemic in a
few fields. In one field on low ground 50 percent of the plants became
infected and died prematurely, causing a reduction in yield of 14 percent.
Detailed studies were made of the symptoms, distribution and conditions
favorable to the development of the disease. Further ones are in progress
and possible control measures will be tested next year.
Fusarium seedpiece decay caused a reduction in stand ranging from
10 to 70 percent and averaging 25 percent on 400 acres of potatoes in the
Federal Point section. The organism was isolated from diseased seed and
its pathogenicity proved by inoculating seed pieces planted in sterilized
soil. It was concluded that the organism was present in the soil and that
moisture and temperature conditions combined with some burning effect
of the fertilizer favored development of the trouble.
Comparisons were made of the susceptibility of different varieties of
potatoes to infection from Rhizoctonia solani as indicated by lesions on the
stems two inches below the surface of the ground six weeks after the date
of planting. Plants of the Katahdin variety were almost free of lesions;
in three fields only 0.0, 0.9 and 1.3 percent of the plants were infected,
while plants of the Spaulding Rose variety in the same fields had infection
rates of 5.2, 4.4 and 9.1 percent. A thousand plants of each variety were
examined. None of the other varieties, including Green Mountain, Irish
Cobbler, Bliss Triumph, Chippewa, U. S. D. A. Seedling 41914 showed any
outstanding resistance with the exception of a medium early Bliss Triumph
from Nebraska.
INVESTIGATION OF AND CONTROL OF BROWN ROT OF POTATOES
AND CLOSELY RELATED PLANTS CAUSED BY
BACTERIUM SOLANACEARUM
State Project No. 143 A. H. Eddins
In experimental plots in the potato growing areas of Hastings and
LaCrosse, soil applications of sulfur applied one season and followed by
finely ground agricultural limestone the next have practically eliminated







Annual Report, 1934


bacterial wilt from potato fields and measurably increased the yield of
marketable tubers. Either sulfur or lime alone was inferior to the sulfur-
limestone combination.
Laboratory investigations showed that the pathogene involved, B. sola-
nacearum, was rendered inactive or killed by the action of the acid when
the reaction of the medium was between pH 4.57 and 4.06. Increasing soil
acidity by sulfur application beyond pH 4.57 probably kills the organism,
since the disease did not reappear when the soil was brought back to pH
5.29 and 5.49 by treatment with limestone.
When grown in wilt-infested soil, the Green Mountain variety showed
only 7.5 percent of tuber infection, while Spaulding Rose developed 37.9
percent infection. The Katahdin and Bliss Triumph varieties were not as
susceptible as the Spaulding Rose but did not possess as marked resistance
as the Green Mountain. Chippewa, Irish Cobbler and U. S. D. A. Seedling
41914 were very susceptible.
Tomato, eggplant, pepper, castor bean, zinnia and okra plants developed
bacterial wilt when grown in infested soil. Tomatoes and eggplants were
most susceptible, all plants being killed.
INVESTIGATION AND CONTROL OF A DISEASE OF CORN CAUSED
BY PHYSODERMA ZEAE-MAYDIS
Purnell Project No. 145 R. K. Voorhees
Inbred lines and crosses were tested during 1933 for resistance to brown
spot and the undesirable lines were discarded at the end of the season.
The desirable inbred lines and crosses were planted this year, 1934, and
were exposed to the usual epiphytotic conditions of brown spot. Also,
several commercial varieties, especially adapted to the South that are not
contained in the present inbred lines and crosses, were planted to test
their reaction to brown spot.
INVESTIGATIONS OF SEEDLING, STALK, AND EAR ROT DISEASES
OF CORN CAUSED BY DIPLODIA SPP.
Purnell Project No. 146 R. K. Voorhees
Since the leaf spot of corn caused by Diplodia macrospora is usually
found only in low moist fields where a high humidity prevails more or less
during the growing season, an experiment was started in the greenhouse
to determine the effect of temperature and humidity upon the occurrence
of the disease. Results obtained show that it develops at an average tem-
perature of 85" F. and 80 percent relative humidity in corn plants in the
tasseling stage. Other tests will be conducted in atmospheres of different
relative humidities.
Cross inoculation studies have shown that species of Diplodia collected
on sweet potatoes, citrus and cotton caused a rot of ears of corn similar
to that due to D. frumenti, the imperfect form of Physalospora zeicola.
They also caused similar rots of oranges, grapefruit, sweet potatoes, cotton
bolls and watermelons. Similar species of Diplodia have been collected
on peanut, watermelon, strawberry, pear, rose and pittosporum. Since
all of these are morphologically similar to D. frumenti, investigations are
in progress to determine, if possible, whether all the forms occurring on
different hosts are D. frumenti. Attempts are being made to produce the
perfect stage in culture.






Florida Agricultural Experiment Station


INVESTIGATIONS ON SEEDLING, STALK AND EAR ROT DISEASES
OF CORN CAUSED BY FUSARIUM SPP.
Purnell Project No. 147 R. K. Voorhees
Studies of the host-fungus relationship of the corn seedling disease
caused by Gibberella moniliformis have been completed during the year
and results prepared for publication. These studies conclude the investi-
gations and the project was closed June 30, 1934.
INVESTIGATIONS OF DISEASES OF FERNS AND ORNAMENTAL
PLANTS
State Project No. 148 W. B. Shippy
The tests to hasten production of Easter lily blossoms by storing the
bulbs under different conditions have been continued this year in greater
detail. The procedures included: Bulbs dug and immediately replanted;
bulbs not dug; bulbs dug at two-weeks intervals throughout the summer
and stored for 30 days at both warm and cool (40' F.) temperatures, then
replanted; bulbs dug simultaneously and stored at warm and later at cool
temperatures, or vice versa, for various periods of time, then replanted
simultaneously; bulbs covered by various packing materials during the
storage period under conditions of either warm or cool storage. Altogether,
30 duplicate plots were set out, and these represented a wide range of
storage procedures. However, they all fell far short of concentrating
blossom production at Easter time (April 1st this year) or giving a fairly
uniform distribution of blossoms throughout the season.
Bulbs that were kept in cool storage from one to two months immedi-
ately prior to planting produced blossoms during December and January.
Certain other treatments stimulated early production of blossoms, while
others were quite late in coming into bloom. As a rule, plants from bulbs
given cool storage were smaller and produced fewer flowers, though many
bulbs so treated produced a second crop of bloom.
INVESTIGATION OF AND CONTROL OF FUSARIUM WILT, A
FUNGUS DISEASE OF WATERMELONS CAUSED BY
FUSARIUM NIVEUM
State Project No. 150 M. N. Walker
The extremely hot and dry weather of the 1933 season checked the
development of wilt early in the season. Consequently, a determination
of the comparative resistance of the various strains of melons could not
be made, and approximately 600 melons were harvested for seed. Some
of these were discarded because the quality and type of melons were un-
desirable and others were discarded because the seedlings failed to show
resistance to wilt in the greenhouse in comparative tests. Even after the
use of these methods of elimination, 250 lots of seed were left for further
trial in the field.
On account of the drought in March, a stand of the plants was not
obtained until after the rains commenced in April. Weekly counts showed
that a number of the strains possessed considerable resistance as compared
with the commercial checks. Progeny of two strains, 61 and 78, showed
up especially well. The former produces a round, dark green melon,
whereas the latter produced a long, dark green melon, and both show
additional desirable characteristics of meat and rind. The uniform charac-
ters of fruit and resistance to wilt indicate that these strains are ready
for commercial trial.
The 1934 season has been the most satisfactory for the wilt studies since
the beginning of the work. Frequent rains during the latter part of the






Annual Report, 1934


season have maintained soil temperatures favorable for development of
the organisms and the failure of the checks has shown that the soil is
uniformly infested. With this information it will be possible to concentrate
attention on developing further those strains showing greatest promise.
INVESTIGATION OF AND CONTROL OF FUNGUS DISEASES
OF WATERMELONS
State Project No. 151 M. N. Walker
The early and late parts of the season of 1934 have been extremely
wet, which has favored all diseases of watermelons. Downy mildew, caused
by Peronoplasmopara cubensis (B. & C.) Cl., has been noted for the first
time since the initiation of the work at Leesburg. In some fields it has
been as injurious as anthracnose from the standpoint of defoliation. The
disease appears capable of even more rapid spread than anthracnose under
ordinary field conditions.
The severity of anthracnose is probably greatly increased by laborers
walking through wet vines sweeping the leaves aside with sticks to locate
and remove cull melons-an operation locally called "pruning". Alternaria
blight has also been noted as being the cause of extensive defoliation, but
in all fields observed no one disease is entirely responsible for the injury.
Gummy stem blight has been observed, but to a lesser extent than during
the 1933 season.
A STUDY OF THE SO-CALLED "RUST" OF ASPARAGUS PLUMOSUS
State Project No. 167 W. B. Shippy
Tests made during the past summer to determine a possible relationship
between sunburning of the foliage and "rusting" proved unfruitful. Sprink-
ling the foliage with water at various times of the day and providing
sunlight exposures varying from full sunlight to indirect light only, and
waterproofing the foliage failed to induce "rust" in several weeks.
With frequent heavy rains during the latter part of May and the first
two weeks of June, rust became prevalent and caused severe shedding of
the sprays and consequent losses. Much of this damage has occurred in
unmowed ferneries in which ventilation was poor due to dense growth.
Tests have shown that copper-containing fungicides reduce this defoliation
considerably and for that reason it has been recommended that the stubble
and short growth should be sprayed with bordeaux after mowing, followed
thereafter by frequent applications of copper-lime dust.
CONTROL OF WILT OF TOMATOES FUSARIUMM LYCOPERSICI SACC.)
IN FLORIDA
Hatch Project No. 180 G. F. Weber and D. G. A. Kelbert
Trials of tomato varieties and strains for resistance to wilt on wilt-
infected soil at the Bradenton Field Laboratory was the principal line of
attack on this project. The Marglobe variety has been planted in the plots
in greater proportion than any other variety, on account of its popularity
with the growers, marketers and consumers, with the hope of isolating a
more resistant strain.
Only a few selections were made from the plantings of the previous
season due to rigid inspection and selection requirements. Progeny of
these were grown during the present season and about 100 single plant
selections were made from 1,800 plants. These trials show that an im-
provement in fruit type and resistance is in process. A number of crosses
between the principal commercial varieties and the most resistant selections
were made, in an effort to obtain a more resistant strain of desirable fruit
quality.






Florida Agricultural Experiment Station


Fig. 3.-Strains of tomatoes were tested at the Tomato Disease Investi-
gations Laboratory, Bradenton, for resistance to Fusarium wilt. Resistant
strains are shown right and left, while susceptible ones are in the center.
CLITOCYBE MUSHROOM ROOT ROT OF CITRUS TREES AND OTHER
WOODY PLANTS IN FLORIDA
Adams Project No. 181 Arthur S. Rhoads
Approximately 10 new host plants have been added to the list, making
a total of 92 different species. During the year isolations have been made
from the following trees and shrubs attacked by mushroom root rot:
acalypha (Acalypha marginata), Arizona cypress (Cupressus arizonica),
crape myrtle (Lagerstroemia indica), guava (Psidium guajava), pome-
granate (Punica granatum), princess flower (Tibouchina semidecandra),
royal poinciana (Delonix regia) from two localities, sand pine (Pinus
clausa) from two localities, and Surinam cherry (Eugenia uniflora). The
mushroom fruiting bodies have developed in all of these cultures, except
the ones from sand pine. These bodies have developed also in cultures from
arbor-vitae (Thuja occidentalis), cassia (Cassia sp.), cape jesamine (Taber-
naemontana coronaria), eucalyptus (Eucalyptus sp.), peach (Amygdalus
persica), and popinac (Acacia farnesiana).
Comparative studies have shown that, although both Clitocybe tabescens
and Armillaria mellea produce rhizomorphs readily in culture, it apparently
is impossible to distinguish between the two organisms on the basis of
rhizomorph development alone in cultures. Cultures of A. mellea and A.
fuscipes have not produced mushroom fruiting bodies on culture media
under the same conditions in which C. tabescens produces them readily.
Numerous trees of different species and ages have been inoculated with
pure cultures of C. tabescens, but so far none of them have died. The
surgical treatment of trees (chiefly citrus) attacked by Clitocybe mush-
room root rot, begun in 1930 and continued to date, has checked the disease,
provided the vitality of the trees was not .too seriously impaired before
treating.
CONTROL OF BLACK SPOT (PHOMA DESTRUCTIVE PLOWR.) OF
TOMATOES IN FLORIDA AND IN TRANSIT
Hatch Project No. 182 W. B. Tisdale and Stacy Hawkins
Work on this project during the year has been primarily a repetition
of experiments reported upon previously; that is, the plants were sprayed







Annual Report, 1934 77

with bordeaux and the fruits were dipped in fungicides in the field immedi-
ately after picking.
Due to dry weather the yield of tomatoes on the pinelands plots was
low, and spraying with bordeaux decreased the yield instead of increasing
it, as was the case during the previous two years. Although it is known
that bordeaux increases transpiration in plants, this is the first time during
the progress of these experiments that the weather has been sufficiently
dry on the Lower East Coast for spraying to decrease yield further.
Black spot of the fruit also was much less severe than during the
previous season, 13 percent having been the maximum percentage that
developed on fruit from non-sprayed plots. The first fruit picked from
sprayed plots showed no black spot, but later pickings showed a low per-
centage. Borax and a sulfur compound plus 0.5 percent soap were again
most effective in preventing the development of black spot.
Fruit stored at a temperature of about 70 F. and 92 percent relative
humidity developed a higher percentage of disease than that stored in a
natural environment of fluctuating temperature and humidity. This was
especially true with fruit picked from old diseased vines.
A STUDY OF STRAWBERRY WILT OR CROWN-ROT
State Project No. 184 A. N. Brooks
Inoculations of potted plants in the greenhouse during the fall and
winter, 1933-84, showed that wilt will not develop when mean daily tempera-
tures average below 70 F. The fungus is both intra- and inter-cellular
in the cortex and pith of rhizomes.
The runner spot stage of this disease was somewhat more prevalent
than it was during 1933. Field observations again showed the inadvisability
of attempting to produce nursery plants on land infected with the causal
organism, Colletotrichum fragariae.
Several sprays and dusts, common and proprietary, have been given
thorough tests for wilt control. Of these, a copper resinate spray and
bordeaux with a proprietary sticker added gave best results.
CERTAIN STUDIES OF DECAYS OF CITRUS FRUITS IN STORAGE
Adams Project No. 193 W. B. Tisdale and Erdman West
Further storage tests with grapefruit from sprayed and non-sprayed
trees grown in three parts of the state, showed that stem-end decay was
from 10 to 20 percent higher in fruit from non-sprayed plots than from
sprayed plots. Again, spraying reduced decay caused by Diplodia more
than it did that caused by Phomopsis. There was little difference in the
percentage of decay in fruits from different sections.
A storage temperature of 48* F. inhibits decay due to Diplodia but will
permit a low percentage of decay due to Phomopsis in 60 days. No decay
developed in grapefruit stored for 60 days at 42" F. but it increased rapidly
after they were removed to laboratory temperatures. Initial decay was
slower in grapefruit removed from storage at 37* and 32 F., but the total
at the end of 20 days was about the same as in fruit that had been stored
at 42 F.
Isolations made from surface-sterilized parts of buttons and stems of
tree-ripe Valencia oranges and Silver Cluster grapefruit showed that
Phomopsis citri and Diplodia natalensis are already in the buttons of a
percentage of the fruits when they are removed from the trees. Therefore
it should not be expected that surface treatments will prevent all decay.
This has been confirmed by actual treatments of large numbers of fruits
with different disinfecting materials.







Florida Agricultural Experiment Station


A STUDY OF THE SPRAYING REQUIREMENTS NECESSARY TO
CONTROL GRAPE DISEASES IN FLORIDA
State Project No. 196 K. W. Loucks
Spraying experiments were carried out to determine the comparative
value of bordeaux spray with and without stickers, and to determine the
best time to apply the spray for controlling fruit rots. With the schedules
used last year, there was no evidence of advantage gained by using stickers.
Spray applications during the blooming and fruit setting periods were
immensely important.
The latter part of last season was very favorable for ripe rot which
destroyed a large portion of the late crop. From field observations there
was only a little difference in the amount of ripe rot in sprayed and non-
sprayed plots.
Sprayed Beacon vines held their leaves-well into the late summer, while
the non-sprayed ones dropped theirs before the fruit ripened, permitting
sunscald of the fruit. These non-sprayed vines were approximately two
weeks later in their development all during the succeeding growing season.
On the other hand, some "Port Wine" vines which were not sprayed the
previous season started growth about 10 days ahead of those that were
sprayed, but set only about a third as much fruit as the sprayed vines.
There was no holdover value of spraying in the control of disease from
the preceding year. Diseases were as severe on vines which had been
sprayed the previous year with good control of diseases and left unsprayed
this year as they were on other vines which had not been sprayed for
three years.
INVESTIGATIONS OF A BARK DISEASE OF TAHITI LIME TREES
Adams Project No. 242 W. B. Tisdale
A preliminary survey has shown that this disease of Tahiti limes occurs
in all sections of the state where limes are grown. In the nursery the point
of attack appears to be determined by thorn punctures or other mechanical






















Fig. 4.-Bark disease of Tahiti limes: left, healthy tree; right, diseased
tree that has been treated by grower-diseased bark and branches removed
from lower portion of trunk and trunk whitewashed.


L







Annual Report, 1934


injuries, and part of the tree above the point of attack dies. The Perrine
lemon is affected in a similar manner.
In the grove, trees may die back from the point where they are cut
off soon after transplanting. Also, after trees have been in the grove from
two to four years, the trunks become infected near the ground and in the
crotches of large branches, resulting in death of the tree or a part of it.
Infection apparently occurs through cracks in the bark and other mechanical
injuries.
Several organisms have been isolated from diseased parts of trees but
the two forms most commonly obtained are apparently Diplodia natalensis
and Phomopsis citri. Diplodia is associated most frequently with the in-
fected areas on the trunks and large branches, while Phomopsis occurs
most frequently in small twigs and young trees.
Inoculation tests have shown that both organisms are aggressive para-
sites. A few other organisms isolated from diseased parts of trees are
also slightly parasitic.
Several methods for controlling the disease have been initiated, but it
will be two or more years before definite results may be obtained.
A STUDY OF SCLEROTIUM ROLFSII IN FLORIDA, ITS HOST
RELATIONS AND FACTORS INFLUENCING ITS
PATHOGENICITY
State Project No. 247 Erdman West
Cultures of the fungus, isolated from 37 sources in Florida, have been
maintained in pure culture in the laboratory for several years.
Seedlings of Crotalaria spectabilis in 4-inch pots of sterilized soil were
inoculated by placing cultures of the organism on the soil surface in contact
with the stems. No infections were obtained. About one month later,
other pots of the plants of the same lot were inoculated in duplicate. A
mulch of green Crotalaria leaves was applied over the inoculum in one
set of the plants and the other was left uncovered. One week after inocu-
lation all of the mulched plants showed infections and died about a week
later. The unmulched plants and the checks remained healthy.
In December, Bountiful beans (Phaseolus vulgaris) that had been
planted in sterilized soil in the greenhouse were inoculated with cultures
from various sources and the pots mulched with bean leaves. Slightly
more than 50 percent of the plants developed infections.
Thus far no constant morphological characters have been discovered by
which the cultures from various sources can be separated and classified.
A STUDY OF ROSE DISEASES IN FLORIDA AND THEIR CONTROL
State Project No. 253 W. B. Shippy
During 1933 roses were treated with the following materials: (1)
ammoniacal copper carbonate, (2) copper-lime dust, (3) lime-sulfur 1:80,
(4) sulfur dust, (5) bordeaux mixture 4-5-50, (6) S. C. A. (combination
of soap, copper sulfate, and ammonia), (7) and (8) two proprietary com-
pounds. Twenty-six applications of materials one to seven were made
on bush roses during the year; 22 applications of materials four, five and
six were made on climbing roses, and eight applications of material eight
were made on part bush and part climbing roses.
No counts were made as to stem cankers formed, but at the close of
the year all dead canes were cut and weighed. Amount of dead wood was
found to coincide very well with severity of defoliation, whether caused
by black spot or fungicide injury. Untreated bushes showed 3.8 times as
much dead wood as the ones receiving the best treatment. All copper-







Florida Agricultural Experiment Station


containing fungicides proved better than either of the sulfur-containing
fungicides. The sulfurs caused severe injury to the foliage during the
summer. While bordeaux gave greater disease control throughout the
season it appeared to inhibit growth and blossom production.
The rose work has been materially extended for 1934. The fungicide
schedule now includes 13 additional materials. Tests other than effect on
disease control include length of sunlight exposure, frequency of watering,
frequency of applying fertilizer, sandy soils with humus and clay added,
mulching, and kind of rootstock.
INVESTIGATIONS OF FRUIT ROTS OF GRAPES
State Project No. 254 K. W. Loucks
Field observations and inoculations made to date indicate that black
rot infects the fruit only during the blooming and early setting stage.
Further inoculations are to be made with ripe tot, bitter rot, and other
fruit rotting organisms.







Annual Report, 1984


CITRUS EXPERIMENT STATION
The work at the Citrus Experiment Station, divided among the fields
of Entomology, Plant Pathology, Chemistry and Soils and Horticulture,
has made progress during the year, but has been seriously handicapped in
some phases because of insufficient plantings and lands upon which to
make them.
The several experimental grove plots, including the source of nitrogen,
high and low potash, source of phosphorus, cover crop, progeny, variety,
cultural, insect and disease control areas and others, have been maintained
and continue to supply data from the varied experimental treatments.
Although not in line with best research practice, it has been necessary
to overlap experiments on the same blocks of trees in some instances, if
the work was to be done at all.
Damage to the groves caused by the storm of September, 1933, was
very considerable but by June, 1934, the citrus plantings at the Station,
for the most part, had outgrown it.'
FLORIDA ORANGE FESTIVAL
For the past 10 years the Citrus Station has cooperated in placing an
educational exhibit at the Florida Orange Festival, held at Winter Haven
in January of each year. The exhibit at first was small, occupying a space
of only 10 by 10 feet. It has grown in size, interest and educational value
each year, the space in 1934 having been 15 by 60 feet.
The exhibit consisted of rootstocks, propagation models, seed selection
displays, citrus fruits of commercial varieties on various rootstocks, numer-
ous uncommon varieties and citrus relatives, and specimens of citrus in-
sects and diseases. Various beneficial and harmful insects and their hosts
were shown, as well as the common methods giving most satisfactory
control. By displays of sprayed and unsprayed fruit, the value of con-
trolling citrus diseases was demonstrated and emphasized. Seven of the
most important grove and transit diseases were illustrated by large cul-
tures of the causal agents and by specimens showing typical symptoms as
they occur on the hosts.
MELANOSE OF CITRUS AND ITS CONTROL
State Project No. 3 Geo. D. Ruehle and W. A. Kuntz
Several spraying experiments for melanose control on different varieties
of grapefruit and oranges have been conducted in three localities of the
citrus area. Bordeaux, bordeaux-oil, and sulfur fungicides were used, at
different seasons-with and without previous pruning. In general bordeaux
gave better control than lime-sulfur sprays, although the degree attained
was dependent to a large extent on the time of application.
Glass slides hung in the foliage of sprayed trees showed that there was
sufficient residue, after 22 days of weathering, of bordeaux on the slides
to prevent germination of all spores of Phomopsis citri. Under similar
conditions, 82.5 percent of the spores germinated following spraying with
lime-sulfur. This experiment demonstrated the superiority of a weak
bordeaux mixture over lime-sulfur in both toxicity and adhesiveness.
Diaporthe crotalariae was isolated several times from citrus buttons,
but melanose lesions did not develop on young grapefruit leaves inoculated
with ascospores of this fungus.
DIEBACK OF CITRUS
State Project No. 21 B. R. Fudge
Previous reports have shown that nitrogen was conspicuously higher
in the tissues of trees suffering from exanthema. This year studies of the







Florida Agricultural Experiment Station


nitrogen, phosphoric acid and potash content of sap from the normal and
abnormal leaves and stems, with and without copper sulfate treatment,
were made. Copper sulfate treatment had a tendency to bring the com-
position of the sap of leaves and stems from exanthema affected trees back
to normal.
Analyses of the juice of fruit from normal and from exanthema affected
trees showed ammoniated fruit to have a higher nitrogen content and
lower citric acid and sucrose content.
DETERMINATION OF THE EFFECT OF VARYING AMOUNTS OF
POTASH ON THE COMPOSITION AND YIELD AND
QUALITY OF THE CROP
Hatch Project No. 22 R. W. Ruprecht
See report of the Department of Chemistry and Soils.
CITRUS SCAB AND ITS CONTROL
State Project No. 24 Geo. D. Ruehle
Extensive experiments in scab control have been conducted in groves
in different sections of the state. By one application of a bordeaux-oil
spray the percentage of blemished fruit was reduced from 97 percent to
less than 10 percent. A dormant bordeaux-oil spray. followed by 2 and 3
applications of a sulfur spray gave only slightly better control while a
second bordeaux spray at petal-fall reduced the infection to 5 percent. Two
bordeaux sprays applied one season, followed by two lime-sulfur applica-
tions the next, have reduced infection to 5 percent.
The results secured indicate that one application of bordeaux-oil, applied
thoroughly at the proper season and under normal conditions, will give
commercial control of the disease.
Lime-sulfur sprays have been found efficacious in controlling light in-
festations of scale-insects, but bordeaux alone seriously reduces the amounts
of "friendly" scale fungi.
Several proprietary spray materials were tested, some of which gave
as good control of scab as bordeaux mixture while others were of little
or no value.
CITRUS PROGENY AND BUD SELECTION
State Project No. 26 J. H. Jefferies
(Cooperative with Bureau of Plant Industry, U. S. D. A.)
The progeny grove, now in its twelfth year, contains 52 strains of
oranges, grapefruit, tangerines and tangelos, each selected from record
trees of the most desirable commercial varieties. Fruit from these numer-
ous selections has been critically examined from year to year and hereditary
defects found have been few and slight.
Requests for budwood are steadily increasing and during the year the
greatest demand has been for the following varieties: Thompson and
Marsh Seedless grapefruit and Valencia, Hamlin, Parson Brown, Temple
and Pineapple oranges. Of the many varieties under test, the Davis Seed-
less and Marsh Seedless grapefruit, Sampson tangelo, and Homosassa and
Parson Brown oranges have made the most vigorous growth.
In the course of systematic observation of the following varieties it has
become evident that different spacing distances are required by the differ-
ent citrus varieties for optimum tree development and maximum utilization
of the lands planted.







Annual Report, 1934


Varieties adapted to close planting:
King orange Valencia orange
Temple orange Hamlin orange
Pineapple orange Surprise Navel orange
Thornton tangelo
Varieties needing wider spacing:
Marsh Seedless grapefruit Foster Pink grapefruit
Davis Seedless grapefruit Silver Cluster grapefruit
Duncan grapefruit Thompson grapefruit
Sampson tangelo
Progenies that have shown unusual merit include:
Davis Seedless grapefruit. A vigorous grower, producing regularly.
Fruit holds late and is accepted by canners.
Reasoner Valencia orange. Vigorous tree; very good quality fruit.
Citra Pineapple orange. Produces a highly colored and exceptionally
good quality fruit on high pine land.
PROPAGATION OF CITRUS PLANTS OF VARIOUS KINDS
State Project No. 34 J. H. Jefferies
Numerous trees propagated in different ways are maintained for both
demonstration and the study of tree reaction. Included are those propa-
gated by:
Sprig grafting at base of rootstock.
Sprig grafting in branches.
Cleft grafting.
Budding.
"Sandwiching", wherein a different variety or species is grown between
the rootstock and the fruiting top. An example is the rough lemon root-
stock budded to grapefruit and the latter afterward budded to orange.
Inarching with young seedlings to rejuvenate old or diseased trees.
Seed propagation, demonstrating the value of discarding the less vigor-
ous seedlings for rootstocks.
Hybridizing, chiefly acid fruits.
TESTING OF INTRODUCED AND NEW VARIETIES AND HYBRIDS
OF CITRUS AND NEAR-CITRUS
State Project No. 35 J. H. Jefferies
Numerous new varieties of citrus and near-citrus, supplied through
the cooperation of the Bureau of Plant Industry and comprising nearly
all brought into the country by the United States Department of Agricul-
ture, are to be grown to maturity and tested for their value as producers
of edible fruits or as rootstocks or ornamentals.
COVER CROP AND GREEN MANURE STUDIES IN CITRUS GROVES
State Project No. 83 W. E. Stokes and J. H. Jefferies
This project has been inactive during the current growing season.
EFFECT OF VARIOUS FERTILIZER FORMULAS
State Project No. 94 R. W. Ruprecht
See report of the Department of Chemistry and Soils.







Florida Agricultural Experiment Station


CITRUS VARIETY TESTS, INCLUDING ROOTSTOCKS
State Project No. 102 J. H. Jefferies
As previously reported, experiments have been initiated with 13 citrus
varieties on 22 rootstocks. The trees are yet too young for comparison or
to give information on which definite conclusions can be based.
DISEASES OF CITRUS APHIDS
State Project No. 114 W. A. Kuntz
This project has been completed. A manuscript covering the results
of the experimental work done will be submitted for publication in the
near future.
INVESTIGATION OF STEM-END ROT OF CITRUS FRUITS CAUSED
BY PHOMOPSIS CITRI FAW.
Adams Project No. 185 W. A. Kuntz
Because of varied results obtained in the control of stem-end rot with
chemical treatments and of a knowledge of the intimate association of the
phomopsis organism with citrus buttons, a technique has been developed
for removing and treating the buttons instead of the whole fruits. By
this method the organisms which are not killed by treating the buttons
can be obtained in culture in a short time. Also large numbers of buttons
can be handled much easier and more rapidly than entire fruits containing
the buttons.
Numerous Pineapple oranges and Excelsior grapefruit of different ages
are being inoculated in the grove to determine the effect of the fungus on
the shedding of fruits and on the development of stem-end rot after the
fruits have matured.
Oranges and grapefruit from sprayed and non-sprayed trees and held
in storage for about 60 days showed that spraying the trees reduced the
amount of stem-end rot in storage. The fruits were usually picked in a
tree-ripe condition.
Duplicate isolations were made from the fruits rotting with the stem-
end type of symptoms to determine what percentage of decay was due to
Phomopsis.
CONTROL OF PURPLE SCALE AND RUST MITES WITH
LIME-SULFUR
State Project No. 233 W. L. Thompson
Three series of tests were made with various combinations of sulfur.
In the experiments where the materials were applied when needed for
mite control, three applications of spray gave protection until the second
week in February. Four applications of dust were made on two plots
and three on another, but the percent of bright fruit on those plots was
much lower than on the sprayed ones.
Dry lime-sulfur, 5 pounds plus a colloidal sulfur, 2 pounds per 100
gallons of water, respectively, gave better results as combined rust mite
and scale control than dry lime-sulfur alone or liquid lime-sulfur alone.
In all plots where either dry lime-sulfur (applied as a spray) or liquid
lime-sulfur were applied, the infestation was reduced. In all plots receiving
a sulfur dust, or a colloidal sulfur, alone, the scale increased.
In the experiments where the sprays were applied for scale control,
liquid lime-sulfur 1-50 plus wettable sulfur 5 pounds per 100 gallons of
water, gave better results as a combined scale and rust mite spray than
the other materials. The other materials tested were: Dry lime-sulfur
5 pounds per 100 gallons, liquid lime-sulfur 1-40, liquid lime-sulfur 1-40






Annual Report, 1934 85

plus hydrated lime 5 pounds per 100 gallons, and a colloidal sulfur 7.5
pounds per 100 gallons. A substantial reduction of scale and whitefly took
place in all the sprayed plots except where a proprietary form of colloidal
sulfur was used. Trees receiving the first application early in April had
some melanose control and fewer whitefly than those given the first appli-
cation in May.
In the experiment in cooperation with the Department of Plant Pathol-
ogy where three applications of different sulfur combinations were made
at two-weeks intervals, a marked reduction in living scale per leaf still was
observable nine months after the last application where a lime-sulfur
1-40, and lime-sulfur 1-40 plus 4 pounds of a colloidal sulfur were used,
respectively. Two plots received a colloidal sulfur; with a slight reduction
in scale on one of these plots and an increase on the other. The plots
receiving bordeaux 11/2-2-50 plus calcium caseinate, and a proprietary
colloidal copper, rcsectively, followed by two lime-sulfurs at two-weeks
intervals, showed a slight increase of scale but less than in the check. The
percent of scale attacked by fungus was as high in the plots that were
sprayed with copper as in the check.






Florida Agricultural Experiment Station


EVERGLADES EXPERIMENT STATION
Production of thousands of hybrid sugarcane seedlings requires much
time and labor in growing them during the years of propagation, testing
and selection. With the completion of the setup for water table studies,
the growing of the various crops on each of the several areas will begin.
Natural increase in the number of livestock has made it necessary to enlarge
the pasture area. The extent and severity of nematode infestations in the
trucking areas of the Glades has emphasized the need for studies in control.
WATER CONTROL CONDITIONS EXPERIENCED DURING THE YEAR
AT THE EVERGLADES EXPERIMENT STATION AND
IN THE OPEN GLADES
Water table level in the open Glades during the fall and early winter
months was rather high as was also the lake level during most of the year.
Some damage resulted to truck crops in the lake region because of insuf-
ficient water control. Planting of crops at the Shawano plantation was
delayed until December due to high water. The East Coast experienced
heavy rains during the late winter and early spring months. These condi-
tions in the Glades area had much to do with the absence of fires and heavy
frosts during the past year.
METEOROLOGICAL RECORDS
The only meteorological data of special interest that were recorded the
past year were those of excessive rains which fell in August and September
and the high winds accompanying the rains of September 4 and 5. (See
Fig. 5.)


i.... showing dlte of evprto ro oe n


-lilt

Epeimen Staio 1' ,.


- r '.- -^ ^ W-.al -r W fS ---- M ". -
7 i




ig. -Graph showing daily trend of evaporation from open pan,
S. i .. \-1 -- I .. . . .......__

I if L I ,



,, i-- *- ... Ni.r "' -_ -






maximum and minimum temperatures, and rainfall at the Everglades
Experiment Station, 1933-34.
RAINFALL AND EVAPORATION
Unusually heavy rains were experienced during the latter part of
August and the first part of September. Most of the rains in August fell
during the last 10 days of the month, while 2.79 inches recorded for Sep-







Annual Report, 1934


tember 4th and 4.21 inches on September 5th fell as one continuous rain
in less than 15 hours. The water table at this time was well over the
surface of the soil and it required continual pumping for 48 hours to bring
it back to normal. (See Table 2.)
TABLE 2.-A COMPARISON OF TOTAL MONTHLY RAINFALL AND EVAPORATION
FROM OPEN PAN DURING THE YEAR WITH THE AVERAGES FOR THE SAME
PERIODS FOR THE PREVIOUS YEARS OF WHICH THERE IS RECORD AT THE
EXPERIMENT STATION.
RAINFALL, INCHES EVAPORATION, INCHES
Month I Average Average
1933-34 1932-33 I1924-34 1933-34 1932-33 1924-34*


August ............
September ......
October ............
November ........
December ........
January ..........
February ........
March ............
A pril ................
M ay ................
June ...............

Totals ..............


12.75
11.89
5.30
4.50
0.12
0.14
1.91
7.10
3.11
5.20
10.15


66.02


10.59
7.43
3.68
12.36
0.50
0.64
0.38
5.42
6.90
4.04
9.51


65.38


8.78
9.75
4.87
2.62
1.05
1.75
1.62
3.59
3.44
4.93
9.81

59.03
II


5.034 6.218 6.149
5.575 5.142 5.455
4.785 5.342 5.005
3.861 3.543 3.812
3.477 3.474 3.405
3.626 3.239 3.510
3.694 4.461 4.062
5.558 6.110 5.647
6.960 6.184 6.347
6.399 7.154 7.037
6.187 6.132 6.069

60.971 64.088 63.005


*Evaporation record poor from July to December, 1924, inclusive; not
included in average values. In 1928-29 during the months of September to
January, inclusive, no evaporation record was taken and these months are
not included in these average values.

From Table 2 it will be seen that there is little difference between the
average annual amount of rainfall and the average annual evaporation
from an open pan surface of water.

TABLE 3.-MEAN MAXIMUM AND MINIMUM TEMPERATURES (FAHRENHEIT)
FOR THE YEAR 1933-34 IN COMPARISON WITH THESE SAME VALUES FOR
THE YEAR 1932-33, AND THE AVERAGE OF THESE VALUES FOR THE PERIOD
1924-1934.


Month


July .................
August ..........
September .....
October ...........
November1 ......
December ........
January ..........
February ........
March ..............
April ................
M ay .................
June ..........


1933-1934


Max.

90.3
87.6
88.3
83.8
75.3
76.8
75.6
74.5
78.5
82.5
85.6
87.5


Min.

70.0
70.7
72.2
68.9
55.5
52.7
52.0
50.1
54.5
58.0
65.0
68.8


1932-1933


Max.

91.3
90.0
85.8
84.0
73.8
80.2
76.3
80.7
78.6
82.7
87.8
86.9


Min.

67.8
69.0
70.7
65.2
57.5
55.9
54.1
54.9
51.5
59.5
64.9
66.1


AVERAGE
1924-1934*
Max. Min.

90.8 69.0
91.2 70.2
88.5 70.5
83.9 65.7
77.5 58.1
76.1 53.9
75.4 51.9
77.5 51.9
77.7 51.8
82.0 57.1
85.4 62.5
88.1 66.9


1No record for November 8, 1932.
Averages do not include values for September through November of
1928, or February through April of 1929.
















TABLE 4.-STACK THERMOMETER READINGS SHOWING GREATEST DAILY RANGE IN EACH MONTH*.


Month 1929-30 1930-31 1931-32 1932-33 1933-34
_(1) (2) (1) | (2) (1) (2) (1) (2) (1) (2)
November........................ 59.0 62.0 42.0 48.0 60.5 64.5 57.0 65.0 54.0 58.0
December ...................... 35.0 38.0 33.5 42.5 52.0 57.0 55.0 61.0 36.0 46.5
January.......................... 54.5 59.0 27.0 36.0 52.0 59.0 36.0 42.5 32.5 40.0
February.......................... 46.0 52.0 39.5 46.5 47.5 55.5 53.0 60.0 44.5 52.0
March .............................. 33.0 41.0 32.0 41.0 32.0 43.5 46.0 58.5 40.5 50.0
A pril ................................ 53.0 59.0 56.0 63.0 .............. ...... .............. .............. ............. ..............


(1) Ground level.
(2) 30 feet above ground level.
* Readings taken only during months of November to April, inclusive.


o





I
C.
9

9
t



0
1

1


S-







Annual Report, 1934


TEMPERATURE
The winter of 1933-34, like the preceding winter, was very mild with
no temperatures deviating very far from the normal. The lowest recorded
were on the night of January 10th when the thermometer showed a mini-
mum reading of 36* F. and on the night of March 11th a temperature of
34* F. was reached. Ground level readings corresponding to the above
were 32.5 F. for the former and 32 F. for the latter date. (See Table 3.)
Table 4 shows the inversion or stratification of air temperatures at the
Everglades Experiment Station as indicated by the widest range of values
for an individual night of each month shown by the daily reading of mini-
mum thermometers at the soil level and at an elevation of 30 feet.
WIND VELOCITY
Wind of rather high velocity and storm intensity was reached in Sep-
tember of this year. On September 3, the anemometer registered a wind
velocity of 50 miles per hour, and on September 4, a rate of 60 miles per
hour was recorded. Accompanying these high winds was a rainfall of
seven inches for the two days.
FORAGE AND FIELD CROP TRIALS
State Project No. 84 A. Daane
Report of work under this project is included in State Project No. 203
of this Station.
FRUIT AND FOREST TREE TRIALS AND OTHER INTRODUCTORY
PLANTINGS
State Project No. 85 R. V. Allison, G. R. Townsend, and R. N. Lobdell
The citrus trees will bear their first normal crop this year. A few
grapefruits, oranges, lemons and limes were on the trees last summer but
most of them fell during the September storm. At present many of the
grapefruit and orange trees are too heavily laden with fruit.
Marsh Seedless and Duncan grapefruits are doing well on sour orange
stock, but the Duncan on rough lemon and Poncirus trifoliata stocks is not
as vigorous. Pineapple oranges on sour orange stock are stronger than on
rough lemon or Poncirus trifoliata. The lemon trees all have gummosis
canker on their trunks, but appear to be more vigorous than last year.
The persimmon trees have set fruit for the first time. Pecans are
affected with a rosette or little-leaf disease which to date has not responded
to zinc treatments. The figs have grown well but are subject to rust unless
dusted with sulfur at regular intervals. Fig fruits have never matured
well. The tung oil trees are growing nicely. All of the avocados have been
lost through wind, or because of wet soil in the late summer.
During the past four years 420 kinds of ornamental trees, shrubs, vines
and herbaceous plants have been planted. This group includes a number
of tropical and subtropical fruits of probable value as ornamentals, but it
does not include any of the plantings in the orchard proper nor the roses or
annual flowers.
Of the 20 species of palms, eight have been successful thus far, and
notably so are Arecastrum Romanzoffianum (Cocos plumosa), Cocos aus-
tralis, Roystonia regia, Sabal palmetto, and the Washingtonias. Equally
notable as a failure has been Coccothrinax argentea.
Of 11 species of ferns seven have proven satisfactory, one of unusual
interest.







Florida Agricultural Experiment Station


Of 48 vines, 30 have shown their adaptability, five have been failures,
and 13 are uncertain. Allamanda cathartica var. Williamsii has had the
longest blooming season of any of the vines and has been more satisfactory
than the variety Hendersonii. Beaumontia grandiflora has made the most
rapid growth of any vine, reaching 50 feet since planting September 5, 1930.
Of Bougainvilleas the best bloomers have been B. spectabilis and B. spec-
tabilis lateritia. Cryptostegia grandiflora has been vigorous and durable.
Grapes have been a failure though making an enormous growth each year.
After dropping their leaves late much of the new growth dies. Very little
fruit is set.
Twenty-seven woody plants might be classified as small shrubs. Severinia
buxifolia, Escallonia glutinosa, Ixoras, Maid of Orleans jasmine, and Thry-
allis glauca may be considered the most successful. Escallonias other than
glutinosa, Gardenias, Genistas, and Hypericums were failures.
Large shrubs and trees number 166 species. The fastest growing tree
has been a Cordia obliqua, which in March, 1931, was a seedling one foot
high and in July, 1934, has a trunk that measures 38% inches in circum-
ference at three feet from the ground. The various species of Ficus were
planted later, while the oldest African mahogany was set but one year ago.
The various plants of this mahogany (Khaya nyasicay have tolerated
existing water conditions here and have grown rapidly. Frost and wind
are yet to be experienced.
Other outstanding trees which have grown off and done notably well
so far are Acacia auriculiformis, Albizzia lebbek, Calophyllum antillanum,
Cedrela odorata, Conocarpus erecta var. sericea, Delonix regia (Poinciana
regia), Grevillea robusta, Ichthyomethia piscipula, Liquidamber styraciflua,
Melaleuca leucadendron, Nectandra coriacea (Ocotea Catesbyana), Quercus
virginiana, Simarubra glauca, and Swietenia Mahagoni.
Of the large shrubs or small trees the most successful have been Acacia
villosa, Chrysophyllum olivaeforme, Duranta plumieri, Eugenia eucalyp-
toides, Gymnanthes lucida, Hamelia patens, Ilex Cassine, Lawsonia inermis,
and Schinus terebinthefolius.
Of fruit trees or fruit shrubs, Antidesma Bunius, Eugenia uniflora,
Flacourtia indica, and Psidium Cattleianum have responded well to their
environment.
Of the 166 trees and large shrubs but 15 were failures; for example,
camphor, chestnut and block locust, while 62 others are as yet uncertain.
One species of Casuarina, C. Cunninghamiana has been definitely suc-
cessful. One pine, Pinus caribaea, seems possible; bald cypresses were
native near Belle Glade and young ones are doing well on the Station
grounds. It is doubtful whether the Eucalyptus is well adapted.
The following clump bamboos have been planted and are all doing well;
Bambusa argentia and B. argentia striata, Bambusa thouarsi, and B. vul-
garis. Several of the running bamboos were planted but were dug out and
discarded because of their objectionable spreading habits.
Forty species of ornamental plants having bulbs, rhizomes or tubers
have been grown; 21 have been successful, 12 failures, and seven are still
uncertain. Perhaps the most interesting of these have been the fine growth
and flowering of Iris Albispiritus and Iris savannarumn on the limy peat
soil of the Station grounds and the most interesting failure, the dwarfed
growth and three or four inch high flower stalk of the great Louisiana
iris, I. giganticae rulea. Of Zephyranthes, two species, Z. candida and Z.
Simpsoni, have been failures.
Of Agaves, the sisal hemp plant (A. sisalana) has not done so well at







Annual Report, 1934


the Station as it has on the better drained custard apple soil at Clewiston.
Dracaenas and Cordylines have grown well both in the slat house and out-
side and would seem to offer possibilities for commercial production. Poin-
settias have been killed by summer rains unless grown on raised beds.
Cactus native to tropical forests have done well; the desert forms, poorly.
A few kinds of orchids are under cultivation, chiefly native sorts, for
a study of their insect relationships.
Among the miscellaneous plants, Bromelia Pinguin, Carica papaya,
Hibiscus rosa sinensis, Polyschias spp. (Aralias), Sansevierias, and Belo-
perone guttata have been especially easy to grow.
SOIL FERTILITY INVESTIGATIONS UNDER FIELD AND
GREENHOUSE CONDITIONS
State Project No. 86 R. V. Allison, A. Daane, R. E. Robertson
and F. D. Stevens
TRUCK CROPS
The plots of the northwest sector of the Station farm have been used
under the same fertilizer arrangement since the fall of 1930. Nine crops
have been removed from each of these areas. The phosphate source plots
of the southeast sector have been under a definite schedule since 1929, with
the removal of about 15 crops per plot.
To obtain additional information relative to the fertilizer needs of
custardd apple" muck soil a series of 40 treatments replicated five times
was established near Bean City. Unfortunately water table control could
not be maintained in this field and it became too dry for fertilizer studies.
Crops of potatoes, celery, and cabbage showed a slight to moderate
positive response to nitrogen in all cases where combination of the element
was made with potash. A depression in yield resulted when potash did not
accompany the nitrogen application. For potatoes, the benefit was more
marked when both phosphorus and potash were included in the formula,
whereas with cabbage, phosphoric acid appeared to lessen the extent of the
response. A crop of peas gave moderate response when the nitrogen was
used with potash alone, although the results were erratic when phosphoric
acid was also included. Carrots, in general, gave slight negative responses
throughout, while crops of beans, both on freshly fertilized plots and those
with residual fertilizers, gave very inconsistent results. As a whole, it
appears that the general response to nitrogen is increasing somewhat with
continued cropping, and for most crops becoming more consistent than on
the earlier plantings.
In a field that had been cropped for four years, celery responded to
phosphates in a rather marked manner, especially in the presence of added
potash where yields were increased up to 30 percent over those with potash
alone.
Duplicating rather closely the results of the past two years, carrots
and potatoes gave slight although consistent response to phosphate when
used with potash, although with the potatoes, tuber size appeared to be
somewhat reduced. Peas and cabbage gave somewhat more evidence of
benefit, particularly when phosphate was used in combination with potash
but in the absence of nitrogen. A crop of beans on freshly fertilized plots
showed little or no response to phosphorus, whereas a crop on residual
fertilizers following cabbage showed consistent yield increases, some as
high as 65 to 113 percent. Lettuce responded strongly but the effect upon
carrots and broccoli was less marked.
In general, phosphoric acid when used without potash gave little or
no response, definite yield depression resulting with crops of cabbage,
potatoes, and beans.







Florida Agricultural Experiment Station


Considering sources of phosphorus, the more insoluble forms such as
floats, colloidal phosphate, and basic slag, gave only a slight response, in
most cases, as compared with yields produced by the soluble superphosphate.
Following in general the results obtained in the past, potash has given
consistent responses with practically all crops, still showing itself to be
the major deficiency and requirement. In all cases the responses have been
outstanding where potash was used in combination with phosphoric acid.
Celery and cabbage evidenced the most marked benefits from the use
of potash with excellent responses also showing on beans and potatoes,
the latter giving an increase in tuber size as well as total yields. The
results with garden peas were somewhat less pronounced and with carrots
rather erratic. Potatoes, on plots not receiving potash, showed complete
breakdown of the foliage at least three weeks before those on the potash
treated areas were severely affected by blight.
In studies concerning sources of potash, potatoes and beans gave mod-
erately depressed yields with both kainit and the muriate, particularly at
the higher rates of application; while cabbage indicated a depressing effect
with the higher quantities only. Peas were adversely affected by the kainit,
showing slight positive responses with the muriate, while carrots gave some
evidence of benefit with both of the chloride carrying sources over the
sulfate of potash checks. Celery also indicated slight additional benefit
from the muriate, the latter giving the high yield plot of the series. Crops
of beans and peas on newly refertilized plots (fourth treatment) gave
evidence of germination failure where kainit in any quantity was used
as the potash source. The higher rates of application gave losses of stand
of from 22 to 34 percent, while the lighter treatments showed loss of from
2 to 11 percent.
FIELD CROPS
At the beginning of fertility work with Dallis grass a negative response
was secured on plots to which phosphorus had been added, and a very
marked increase in yields resulted from the use of potash. During the past
year the potash response still continues but largely on plots where it has
been applied in combination with phosphorus. The yields from the check
plots were about equal to the yields secured from the phosphorus plots
while the potash fertilized plots returned 50 percent greater yield. By the
application of both phosphorus and potash the yields over the check plots
were more than doubled and when the amounts of these two fertilizers were
doubled the yields were further increased by 60 percent. No significant
results were secured through the use of manganese or nitrogen in this
series of plots.
The third crop (second stubble) of two contrasting varieties of cane,
growing in sawgrass soil, produced about the same tonnage but with a
decreasing sugar recovery where soluble phosphates were used with potash
over results with potash alone. The same general findings were obtained
with rock phosphate. With basic slag as the phosphorus source both yields
and sugar recovery were slightly increased. Potash still remains the
principal fertilizer requirement for sugarcane. It may be expected that
the need for phosphorus will increase as the fields become older. The
chloride source of potassium (muriate) continues to do equally as well
as the sulfate form.
Peanuts continue to give a decided response to potash though there are
some indications of increased yields due to phosphorus which was applied
in 1930. During the past year lower yields were secured from plots to
which treble amounts of phosphorus were applied in 1931 than from those
plots to which only a single amount had been added. In the case of potash
the reverse was true; as the amount of this fertilizer was increased from







Annual Report, 1934


one to three times the quantity called for in the basic formula the yields
likewise showed a decided increase. It is also apparent that there is little
difference in crops on plots to which potash only had been added and those
to which both potash and phosphorus had been applied.
Shallu in particular and corn and cane to a less extent are sensitive to
applications of soluble phosphates. Soils that have been cropped for sev-
eral years and from which 10 to 12 crops have been removed are exhibiting
a need for phosphatic fertilizers. Earlier applications of phosphorus to
carpet and Dallis grass plots are now showing increased yields in the
presence of potash. Here, too, the response is greater to the more soluble
forms than to the insoluble forms. Favorable responses are obtained also
with such crops as rape, turnips and broccoli. With almost every crop
grown, limed plots have produced very poor yields.
INSECT PESTS AND THEIR CONTROL
State Project No. 87 R. N. Lobdell
This year it has again been necessary to do most of the work with
certain insects in cooperation with farmers of the area. On the whole,
however, due to an autumn of more than usual rainfall and to the more
general practice of early and efficient control measures, insect pests in
the lake region have caused less damage this season than last.
Work on this project has been chiefly on the following insects:
CUTWORMS
Life histories have been continued on Feltia annex and Agrotis ypsilon,
and begun on the following other noctuids: Laphygma frugiperda, Elaphria
nucicolora, Elaphria chalcedonia, and Cirphis latuiscula (especially impor-
tant). All of the above have assumed cutworm habits in sugarcane. The
following parasites have been bred and identified from these: Reichertella
sp., Enicospilus purgatus, and Bassus texanus. Common cutworm baits
have been used for control in contrast with the newer oil-rock phosphate
baits with results justifying more extensive use of the latter poisons,
especially in rainy weather.
BEAN JASSIDS
(Empoasca fabae, Eugnathodus abdominalis and Empoasca sp.)
An entomogenous fungus, possibly a species of Empusa, was a factor
of control in the season of 1933-34. When it became necessary to use
insecticides the sulfur-pyrethrum-derris dusts gave best control.
Prompt destruction of plants after harvest again this season demon-
strated its great value in delaying the time of heavy infestation and the
practice is followed by an increasing number of growers.
APHIDS
The English pea aphid, Illinoia pisi, continues to be most difficult to
control by sprays and dusts. In spite of the great difficulty in determining
the exact credit due to an insect predator and not to some local condition,
the release of a lady-beetle, Hippodamia convergens, at the first appearance
of the pest seemed worthwhile. With other aphids, good control was se-
cured by the use of light miscible oils or where the foliage was too tender
for such sprays, from hardwater soap sprays.
VELVET BEAN CATERPILLAR (Anticarsia gemmatilis)
Fluosilicates this year proved rather unsatisfactory, due to increased
burning of foliage, even on peanuts. Sulfur-pyrethrum dusts were better.
CORN EAR WORM (Heliothis obsoleta)
The above insect and Laphygma frugiperda and Bomolocha manalis
were three serious insect enemies of corn during the year. Heaviest dam-


I







Florida Agricultural Experiment Station


age was to the late spring crop. By June, parasites, especially Tachina
flies, had become very abundant. Arsenate of lead-lime dusts, sulfur-
fluosilicate dusts, and powdered tobacco-fluosilicate dusts were used but
burning was excessive. Sulfur-pyrethrum-derris dusts were effective but
had to be put on six times. For the earlier crops, dustings of the new silks
only was less expensive and yet effective.
CUCUMBER BEETLES (Diabrotica balteata, D. 12-punctata, and D. vittata)
For the early crop, dusting twice a week with sulfur-pyrethrum-derris
dust was sufficient to secure harvest from cucumbers, squash and Indian
gourds; though mosaic appeared and spread rapidly. For the late crop,
only acorn squash and Indian gourds came through to harvest. An un-
successful effort was made to cross the native Indian gourds on several
squash. This cross will be repeated with the fall crop.
The parasite, Trichogramma minutum, was again used to control the
pickle worm, but was not needed on the East Coast where constant dusting
against the beetles is practiced.
INSECTS ATTACKING LIVESTOCK
The improved field fly trap is used readily by the cattle. It has been
found to contain houseflies, horseflies, stable flies, and a long list of mis-
cellaneous insects. Life histories of four species of horseflies have been
begun.
SOILS INVESTIGATIONS
State Project No. 88 R. V. Allison and R. E. Robertson
In practically all cases where crop failures have occurred on alkaline
soils, excellent results were obtained by the use of sulfur and/or manga-
nese. With the cooperation of the Palm Beach county agent, M. U. Mounts,
many soil conditions of the nature here mentioned, not only in the Glades
proper, but also along the East Coast, have been studied. Studies of this
problem will continue.
WATER CONTROL INVESTIGATIONS
State Project No. 89 R. V. Allison and B. S. Clayton (USDA)
Due to the perishable character of the Everglades soils, careful studies
on water table control become of paramount importance in the matter of
their protection against destruction by fires or by natural oxidation with
subsequent shrinkage. The exceedingly flat character of this great area
makes a thorough understanding of water disposal and control from the
drainage standpoint an absolute necessity in the practical development of
these lands for agricultural purposes.
During the past year the maintenance of records on water levels as
taken from observation wells located on the Everglades Experiment Station
property, in outside areas along the southern and eastern shores of Lake
Okeechobee, and in the Glades has continued. Valuable information is ob-
tained in regard to soil water movement under varying conditions which
later may be compared to the ground water movement as influenced by the
construction of dykes around the southern part of the lake.
Evaporation studies from soil surfaces are made under cropped and
uncropped conditions. At present the approximate water requirements of
cane are determined by growing the crop in large tanks with the water
held at a constant level.
It is hoped that the investigations of the relation of water table eleva-
tions to crop development can begin in the fall. In the setup for these
studies the water control conditions for each of the eight areas are as
follows:






Annual Report, 1934 95






















Fig. 6.-Westward view of the area devoted to water table studies.
Each block 80'x220', exclusive of borders. On the two blocks to the left,
'overhead sprays have been established.

Water Level
Area Below Soil Surface
No. (in inches)
1 -......... ..........-----....--.. ----- 30 (with overhead spray)
2 ......---............- ................... ..... 12
3 ..........------- ..........-....- ..- 21
4 ............ ...- -......... .-- ........-..... 30
5 ----.....- ... ..... .... .... ..... ........ ... 39
6 ----..............---- ---. ........... 48
7 -----..............----....----- ..-.--.- ...- -(fluctuating water level)
8 ........----.~..... --..... ...-- ---....-- ...... 48 (with overhead spray)

The first crop grown on these areas was corn which was planted in
four foot rows and two feet apart in the row on December 4, 1933. A
mixed fertilizer of the formula 0-0-18-3-2 and at the rate of 400 pounds
per acre was applied just prior to planting. (The last two places in the
formula are for copper and manganese, respectively, supplied as sulfates.)
The corn which was grown for soil variability studies was harvested March
21 and 22, with yields taken on small plots 12 by 16 feet. A second appli-
cation of fertilizers was made just previous to planting a second crop of
corn, using an 0-8-24-3-3 formula and at the rate of 400 lbs. per acre.
This corn shows a much more uniform growth and the yields will be taken
in the same manner as the first. The water table levels have been kept
uniform while growing these crops to study the heterogeneity of the soil.
STUDIES IN CROP ROTATION
State Project No. 90 A. Daane
A new field in the southeast sector for the resumption of crop rotation
studies has been plowed, moled, and ditched in preparation for laying out
the plots, and crops will be planted this fall.
Studies in crop rotation for the control of nematodes was begun the






Florida Agricultural Experiment Station


past year at the Brown Company farm. Shortly after the establishment
of the crops in this area the work had to be abandoned because of lack of
water control.
STUDIES UPON THE ROLE OF SPECIAL ELEMENTS IN PLANT
DEVELOPMENT UPON THE PEAT AND MUCK
SOILS OF THE EVERGLADES
State Project No. 168 R. V. Allison, J. R. Neller and R. E. Robertson
A renewal of work relating to the use of special elements for fertilizer
purposes in the organic soils of the Everglades has been undertaken to
aid in the correction of certain phases of malnutrition that have developed
with sugarcane and citrus crops in some areas. In addition, the work has
been extended to ascertain the influence that various elements may have
upon the nature of the organic decomposition that is taking place in Ever-
glades soils during the course of their cultivation.
In view of the decisive results that were obtained with compounds of
copper, manganese and zinc at this station several years ago, it seemed
important that these should be included in the studies along the lines sug-
gested above. Of these, copper sulfate and manganese sulfate already have
an important place in the practical agriculture of the Everglades. It was
felt that the role of certain other elements, namely, silicon, magnesium,
iron, and boron should be investigated, particularly since sawgrass peat is
high in calcium, low in silicon, and with the response to compounds of iron
and boron largely unknown.
The field plot trials with citrus, in the thin or marginal muck near
Davie, include also a series of fertilizer variations involving nitrogen, phos-
phorus and potassium. These plots comprise about seven acres of a grove
of Valencia orange trees set out six years ago. The sugarcane plots are
in the vicinity of Canal Point where the cane, though of good vegetative
growth, failed to mature and develop the proper condition of purity and
of sucrose content.
In conjunction with experiments relating to the effects of the materials
mentioned above upon various crops grown on the Station farm, a study
is under way to ascertain some of the effects that they may have upon the
decomposition of the soil organic matter. As discussed elsewhere in this
report, certain measurements of biological activity are also being made.
This work involves the influence that the various fertilizer and soil amend-
ment elements may have upon biological transformations in the soil in the
presence and in the absence of fresh energy materials such as green
manures.
STUDIES UPON THE PREVALENCE AND CONTROL OF THE SUGAR-
CANE MOTH BORER, DIATRAEA SACCHARALIS FAB.,
IN SOUTH FLORIDA
State Project No. 169 R. N. Lobdell
With the help of Carlos Goff the borer counts on 50 different field areas
of cane were completed before they were harvested and show for the whole
a population slightly smaller than that of last year. General use of fire
in the harvesting processes reduces the number of surviving borers; and
long continued excessive rains during the autumn killed many just hatched
larvae while they were still in the leaf whorl. Benefits accruing from the
release of Trichogramma were not definitely established.
The wasp-like parasite, Ipobracon rimac, was introduced in 1931 to a
field near Canal Point. This field showed the highest borer population
observed up to that time in the Glades. During the harvest of 1932-33







Annual Report, 1934


the field was accidentally set on fire and in order to put out the burning
muck it became necessary to disk up the land. A portion of the colony
that had migrated to a neighboring field survived and was increasing in
numbers in the presence of an abundant food supply when during the
harvest of 1933-34 it was burned. Some 30 days of collecting and rearing
of borers from this and nearby fields since then have failed to establish
the continued presence of Ipobracon.
STUDIES OF THE PREVALENCE AND CONTROL OF RODENTS
UNDER FIELD AND VILLAGE CONDITIONS
State Project No. 170 R. N. Lobdell
No cheap and practical "rat lime" has as yet been worked out for use
in villages and in the wooden tunnels which have been placed along low
chicken wire fences to supplement traps and poisons. Nor has the search
for an effective and attractive waterproofing of the poisoned grain been
successful.
Less trouble has been experienced during the past year by the truckers,
chiefly as a result of the thorough campaigns of the Southern Sugar Com-
pany and the earlier and more complete destruction of the summer weed
crop over the whole trucking area.
The importance of rotating poisons and baits in general work is to be
especially stressed.
CANE BREEDING EXPERIMENTS
State Project No. 171 B. A. Bourne
During the past year considerable effort was devoted to the chemical
analysis and field examination of 1,170 seedlings of the F. 31 series estab-
lished in line tests. On the basis of both early and late analyses, growth
records and disease-resistance studies, the 1,170 varieties in line test were
reduced to approximately 72. Among the latter, notes on blooming and
suitability for use as parent canes in further breeding trials were made.
Indications are given that at least 14 promising "F. 31" canes are
earlier in maturity than Co. 281, the earliest of the commercial varieties.
Since several of these early types give indications of higher tonnage, larger
stalks and cheaper cost of harvesting and handling, a valuable source of
future breeding canes is now available for the intensification of such fac-
tors as earliness, yield and stalk size.
The results of chemical and other selection tests on the various "F. 31"
seedling populations were studied statistically and again show clearly the
value of the crosses POJ. 2725 X CP. 27-35, Co. 281 X CP. 27-108 and D. 74
X CP. 27-108 in the order listed when compared with a number of other
combinations.
Preliminary comparative trials of a large number of seedling progeny
in North Florida from several combinations indicate considerable promise
for the development of superior sirup and forage canes for that region
from such combinations as POJ. 2725 X CP. 27-34 and Co. 281 X CP. 27-35.
Because of lack of vigor and desirable agricultural qualities, the total
seedling progeny of the "F. 32" sugarcane X sweet sorghum crosses has
been reduced to only three selections, all of the cross POJ. 2725 X Texas
Seeded Ribbon. The numbers retained are F. 32-10, 47 and 55.
Results of the current breeding season are summarized in Table 5. It
should be noted that certain valuable back-crosses with early maturing,
locally bred canes have been accomplished, e.g., POJ. 2725 X F. 30-26,
POJ. 2725 X F. 30-20, F. 30-6 X CP. 27-108, F. 30-16 X CP. 27-108. Further,
for the purpose of intensifying the factor of early maturity while retaining






Florida Agricultural Experiment Station


good yield and stalk size, such important combinations as F. 30-6 X F.
30-16, F. 30-16 X CP. 27-35 and F. 29-285 X F. 30-26 have been effected.
A total of 3,081 seedlings from 11 different combinations have been planted
in the field for future study.


Fig. 7.-Original stool of F. 32-47, hybrid between P. O. J. 2725 sugar-
cane and Texas Seeded Ribbon sweet sorghum. Planted June 13, 1933 anc
photographed March 22, 1934.




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