-UNIVERSITY

R. IG ULT",U R E-7PE, IMENT
ILIN'TION

RT OR TMVVISCAL YVARJE DIN
JUNE

'14

UNIVERSITY OF FLORIDA

AGRICULTURAL EXPERIMENT
STATION

REPORT FOR THE FISCAL YEAR ENDING
JUNE 30, 1929

CONTENTS

PAGE

REPORT OF DIRECTOR ............................................... 5
Financial Resources, 5 ; The Mediterranean Fruit Fly, 6 ; Changes in Staff. 7 ; Proj-
ect List, 9.
REPORT OF BUSINESS MANAGER .................................... 13
PUBLICATIONS ................................................. 16
Bulletin Editing, 16; News Stories, 18; Radio, 19; Miscellaneous, 19.
L IBRARY ........................................................ 20
AGRICULTURAL ECONOMICS ......................................... 22
Survey of 500 General Farms, 22; Study of Cost of Picking, Hauling and Packing
Citrus, 22; Citrus Transportation Study, 23; Dairy Study, 23; Cotton Grade, Staple
and Price Study, 24; Truck Crop Competition, 24 ; Pecan Study, 25.
A GRONOM Y ......... .......................... ..................... 26
Peanut and Corn Fertilizer Tests, 26; Peanut Breeding, 27; Effect of Potash on Pea-
nuts, 27 ; Effect of Land-Plaster on Peanuts, 28; Crop Rotation, 28 ; Variety Tests,
28 ; Top-Dressing Oats, 29 ; Winter Legume Studies, 29 ; Summer Cover Crop Studies,
30; Green Manure Studies, 30; Bahia Grass, 31; Corn Improvement, 32; Time of
Planting Corn, 33; Crop Adaptation Tests, 33; Pasture Fertilization, 33; Lawn and
Golf Grass Studies, 35.
ANIMAL HUSBANDRY ......................... ...... ............... 36
Hemorrhagic Septicemia, 36; Chlorine Treatment of Infectious Mastitis, 36; Rela-
tion of Conformation and Anatomy of a Cow to Her Milk Production, 37; High Pro-
tein for Dairy Animals, 37; Soybean Silage, 38; Beef Cattle Grazing Tests, 38; Cost
of Wintering Steers, 39; Grazing Crops vs. Dry Lot Feeding for Pork, 40; Swine
Kidney Worm, 40; "Leeches" of Horses, 41; Fowl Paralysis, 41; Manson's Eyeworm,
42; Diagnostic Laboratory, 42.
CHEMISTRY..... .......................... .................... 43
Dieback of Citrus, 43; Effect of Potash on Yield and Quality, Citrus, 44; Fertilizing
Satsumas, 44; Potash Carriers for Citrus, 45; Fertilizing Citrus on Muck, 45;
Various Citrus Formulas, 45; Concentrated Fertilizer Studies, 46; Effect of Green
Manures on the Soil, 46; Fertilizer Treatments, Tomatoes, 48; Pecan Fertilizer
Tests, 48; Mineral Constituents of Cattle Feeds, 48.
COTTON INVESTIGATIONS ........... ............................ 49
Breeding, 49; Boll Weevil, 50; Rust, 51; Seedling Diseases, 51; Wilt, 52; Nutrition
and Growth, 52.
ENTOMOLOGY .............................. ...................... 53
Velvet Bean Caterpillar, 53; Florida Flower Thrips, 53; Root-Knot, 54; Beneficial
Insects, 54; Larger Plant Bugs, 55; Bean Jassid, 56; Citrus Aphid, 56; Pecan In-
sects, 57; Life History Studies of the Cockroach, Intermediate Host of Manson's Eye-
worm, 58.
H OME ECONOMICS .................... ........ ........ ........ 59
Spoilage of Canned Vegetables, 59; Vitamin A in Animal Nutrition, 59; Constitu-
ents of Citrus Fruits, Loquats, Roselle and Guava, 60; Nutritional Survey, Five
Counties, 61.
H ORTICULTURE ..................... .......... ................ 63
Shrubs and Ornamentals, 63 ; Variety Tests of Berries, 63; Variety Tests of Grapes,
64; Rootstocks for Satsumas, 64; Physioldgy of Fruit Production, 64; Propagating,
Planting, and Fertilizing Tung-Oil, 65; Diseases and Insects Affecting the Pecan,
65 ; Pecan Variety Tests, 65; Cooperative Pecan Fertilizer Tests, 66; Variety and
Stock Tests of Pecans, 66; Rejuvenation Test, Pecans, 66; Pecan Cover Crop Tests,
66; Phenological Studies on Truck Crops, 66.
PLANT PATHOLOGY ................................................. 68
Citrus Studies: Gumming, 69; Melanose and Stem-End Rot, 71; Scab, 72; Diseases
of the Citrus Aphid, 72; Avocado Fruit Spot, 73; Asparagus Fern Survey, 73; Truck
Crop Studies: Seedbed Diseases, 73; Downy Mildew of Cucurbits, 74; Bacterial Dis-
eases of Cucurbits, 75; Nailhead Rust of Tomatoes, Cause and Control, 75; Straw-
berry Diseases, 76 ; Strawberry Anthracnose, 76 ; Crimps or French Bud, 77 ; Alter-
naria Tuber Spotting, Irish Potatoes, 78; Potato Diseases, 78; Late Blight, 79;
Rhizoctonia, 79 ; Corn Disease Investigations, 79 ; Diseases of Pecan Trees. 80 ; Proj-
ects Dropped, 81.
THE CITRUS EXPERIMENT STATION ................................ 82
Progeny and Bud Selection, 82; Propagation, 82; New Varieties and Hybrids of
Citrus and Near-Citrus, 82 ; Cover Crops. 83; Variety Test, Including Rootstocks, 84.
THE EVERGLADES EXPERIMENT STATION ............................. 85
September Hurricane, 85; Rebuilding and Improvement of Property, 88; Forage,
Truck and Field Crops, 90; Fruit and Forest Trees. 90 ; Fertilizer Experiments, 90;
Insect Pests and Plant Diseases, 94; Soil Investigations, 94; Drainage Studies, 95;
Rotations, Fertilizer and Cultural Practices, 95; Greenhouse and Laboratory Work,
95.
THE TOBACCO EXPERIMENT STATION ............ .... ................ 97
Diseases, 97; Variety Tests for Resistance to Black Shank, 98; Fertilizer, Shade
Tobacco, 101.

Hon. Doyle E. Carlton,
Governor of Florida,
Tallahassee, Florida.
SIR: I have the honor to transmit herewith the annual report
of the Director of the University of Florida Agricultural Experi-
ment Stations for the fiscal year ending June 30, 1929.
Respectfully,
P. K. YONGE,
Chairman, Board of Control.

Hon. P. K. Yonge,
Chairman, Board of Control.
SIR: I have the honor to transmit herewith the annual report
of the Director of the University of Florida Agricultural Experi-
ment Stations 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.

BOARD OF CONTROL

P. K. YONGE, Chairman, Pensacola
E. W. LANE, Jacksonville
A. H. BLENDING, Leesburg
W. B. DAVIS, Perry

FRANK J. WIDEMAN, W. Palm Beach
J. T. DIAMOND, Secretary, Tallahas-
see.
J. G. KELLUM, Auditor, Tallahassee

STATION EXECUTIVE STAFF
JOHN J. TIGERT, M.A.,LL.D., President IDA KEELING CRESAP, Librarian
WILMON NEWELL, D. Sc., Director RUBY NEWELL, Secretary
S. T. FLEMING, A.B., Asst. Director K. H. GRAHAM, Business Manager
J. FRANCIS COOPER. M.S.A., Editor RACHEL MCQUARRIE, Accountant
ERNEST G. MOORE, M.S., Asst. Ed.
MAIN STATION-DEPARTMENTS AND INVESTIGATORS

AGRONOMY
W. E. STOKES, M.S., Agronomist
W. A. LEUKEL. Ph.D., Asso.
C. R. ENLOW, M.S.A., Asst.*
FRED H. HULL, M.S.A., Asst.
ANIMAL HUSBANDRY
A. L. SHEALY, D.V.M., Veterinarian,
in Charge
D. A. SANDERS, D.V.M., Asst. Vet.
E. F. THOMAS, D.V.M., Asst. Vet.
R. B. BECKER, Ph.D., Asso. in Dairy
Husbandry
C. R. DAWSON, B.S.A., Asst. Dairy
Investigations
W. N. NEAL, Ph.D., Asst. in Animal
Nutrition
CHEMISTRY
R. W. RUPRECHT, Ph.D., Chemist
R. M. BARNETTE, Ph.D., Asso.
C. E. BELL, M.S., Asst.
H. L. MARSHALL, M.S., Asst.
J. M. COLEMAN, B.S., Asst.
J. B. HESTER, B.S., Asst.
COTTON INVESTIGATIONS
W. A. CARVER, Ph.D., Asst.
M. N. WALKER, Ph.D., Asst.
E. F. GROSSMAN, M.A., Asst.
RAYMOND CROWN, B.S.A., Field Asst.

ECONOMICS, AGRICULTURAL
C. V. NOBLE, Ph.D., Ag. Economist
BRUCE MCKINLEY, A.B., B.S.A., Asst.
M. A. BROKER, M.S.A., Asst.
R. H. HOWARD, B.S.A., Field Asst.
JOHN L. WANN, B.S.A., Asst.
ECONOMICS, HOME
OuID4 DAVIS ABBOTT, Ph.D., Chief
L. W. GADDUM, Ph.D., Asst.
C. F. AHMANN, Ph.D., Asst.
ENTOMOLOGY
J. R. WATSON, A.M., Entomologist
A. N. TISSOT, M.S., Asst.
H. E. BRATLEY, M.S.A., Asst.
HORTICULTURE
A. F. CAMP, Ph.D., Horticulturist
M. R. ENSIGN, M.S., Asst.
HAROLD MOWRY, B.S.A., Asst.
G. H. BLACKMON, M.S.A., Pecan
Culturist
PLANT PATHOLOGY
W. B. TISDALE, Ph.D., Plant Path.
G. F. WEBER, Ph.D., Asso.
A. H. EDDINS, Ph.D., Asst.
K. W. LOUCKS, B.S., Asst.
ERDMAN WEST, B.S., Mycologist

BRANCH STATION AND FIELD WORKERS
Ross F. WADKINS, M.S., Lab. Asst. in Plant Pathology (Quincy)
JESSE REEVES, Foreman, Tobacco Experiment Station (Quincy)
J. H. JEFFERIES, Superintendent, Citrus Experiment Station (Lake Alfred)
W. A. KUNTZ, A.M., Assistant Plant Pathologist (Lake Alfred)
J. FRANKLIN FUDGE, Ph.D., Assistant Chemist (Lake Alfred)
W. L. THOMPSON, Assistant Entomologist (Lake Alfred)
GEO. E. TEDDER, Foreman, Everglades Experiment Station (Belle Glade)
R. V. ALLISON, Ph.D., Soils Specialist (Belle Glade)
L. O. GRATZ, Ph.D., Associate Plant Pathologist (Hastings)
A. N. BROOKS, Ph.D., Associate Plant Pathologist (Plant City)
A. S. RHOADS, Ph.D., Associate Plant Pathologist (Cocoa)
STACY 0. HAWKINS, M.A., Field Assistant in Plant Pathology (Homestead)
D. G. A. KELBERT, Field Assistant in Plant Pathology (Bradenton)
R. E. NOLEN, M.S.A., Field Assistant in Plant Pathology (Monticello)
FRED W. WALKER, Assistant Entomologist (Monticello)

*In cooperation with U. S. Department of Agriculture.

Report for the Fiscal Year Ending
June 30, 1929

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 Stations, together with the reports of the heads of
the several departments, for the fiscal year ending June 30, 1929.
Respectfully,
WILMON NEWELL,
Director.

INTRODUCTION
A summary of the activities of the various departments in the
Experiment Station and Branch Stations, and reports of the prog-
ress that has been made with the projects under investigation are
given in the following pages.
The financial resources of the Experiment Stations for the fiscal
year just closed have been as follows:
Federal Adams Fund ............................$ 15,000.00
Federal Hatch Fund .............................. 15,000.00
Main Station, Gainesville ..................... 236,999.11
Citrus Station, Lake Alfred ....................... 18,291.30
Tobacco Station, Quincy .......................... 15,276.05
Everglades Station, Belle Glade.................... 60,993.92
Station Incidental Fund .................... .. .. 24,285.67
Total .............. ....... ................ $385,846.05
Federal Purnell Fund, not included above........... $ 50,000.00

On account of the financial condition of the State Treasury the
Experiment Stations, along with all other state institutions, have
been under the necessity of curtailing expenditures during the
year. A program of rigid economy was put into effect last fall,

Florida Agricultural Experiment Station

in all departments, and in addition some lines of work were tem-
porarily abandoned. At the close of the year $46,846.43 of funds
that would ordinarily have gone into research work were allowed
to revert. As this amounted to more than 13 percent of the total
state funds available for research work during the year, it can be
readily understood that all lines of work have been affected. In
addition to the curtailment of work, all departments closed the
year with very low stocks of supplies, chemicals, and equipment
usually purchased during the spring and early summer months.
The Everglades Station was excepted from the general pro-
gram of economy on account of its severe losses in the storm of
September, 1928. Its funds, to a considerable extent, were used
in repairing and replacing the property lost in the storm.

THE MEDITERRANEAN FRUIT FLY
On April 6, 1929, the Mediterranean fruit fly was found to be
present in a citrus grove near Orlando. Other infestations were
soon found and the State Plant Board promptly took measures
looking towards control and eradication.
In organizing his forces for the fruit fly control and eradication
campaign, the Director, acting as Commissioner of the State Plant
Board, felt justified in calling heavily on the Experiment Station
for the temporary use of its staff personnel. In addition to devot-
ing the greater part of his own time to organizing and directing
this campaign, the Director assigned the following members of
the Experiment Station staff to the work, with headquarters at
Orlando. (Unless otherwise stated, the worker was from the
main station at Gainesville) :
Dr. A. F. Camp, Head, Department of Horticulture; Harold
Mowry, Assistant Horticulturist; G. H. Blackmon, Pecan Cul-
turist; Dr. M. N. Walker, Asst. Cotton Specialist; E. F. Grossman,
Cotton Entomologist; Dr. D. A. Sanders, Assistant Veterinarian;
Erdman West, Mycologist, Dept. Plant Path.; Miss Ruby Newhall,
Secretary; H. E. Bratley, Lab. Asst. in Entomology; Fred W.
Walker, Asst. Entomologist, Pecan Lab., Monticello; D. G. A. Kel-
bert, Field Asst. in Plant Path., Bradenton; Dr. A. S. Rhoads,
Assoc. Plant Path., Cocoa; and Stacy Hawkins, Field Asst. in
Plant Pathology, Homestead.
It is the intention to release the Experiment Station men and
return them to their regular duties as promptly as possible. At
the close of the fiscal year, however, the organization of the fruit
fly work had not proceeded far enough to make this possible.

Annual Report, 1929

CHANGES IN STAFF
Dr. R. B. Becker was appointed Associate in Dairy Husbandry
January 1, 1929.
F. X. Brenneis resigned as Assistant in Dairy Investigations
February 1, 1929.
H. E. Hammar, Field Assistant, Everglades Station, was
granted leave of absence without pay for one year, August 1,
1928, to July 31, 1929.
R. H. Howard was appointed temporary Field Assistant, De-
partment of Agricultural Economics, effective July 15, 1928, and
terminating February 10, 1929.
J. H. Hunter resigned as Assistant Agronomist at the Ever-
glades Station October 1, 1928.
A. O. Kay, Drainage Engineer at the Everglades Station, was
paid part-time salary from Continuing Appropriation Drainage
Board funds, effective August 1, 1928, and terminating April 30,
1929.
Mrs. Thelma C. Kent was appointed Assistant to the Accountant
November 1, 1928.
Mrs. A. L. Landers resigned as Assistant to the Accountant
October 1, 1928.
Mrs. J. M. Morrison resigned as Housekeeper, Everglades Sta-
tion, September 30, 1928.
James A. Naftel was appointed Field Assistant at the Ever-
glades Station August 7, 1928; reappointed as Laboratory Assis-
tant September 17, 1928, and resigned October 3, 1928.
Dr. W. M. Neal was appointed Assistant in Animal Nutrition,
Department of Animal Husbandry, June 1, 1929.
E. R. Purvis was appointed to the fellowship offered by the
Natural Products Company of Ocala, effective September 17, 1928.
Dr. J. L. Seal resigned as Associate Plant Pathologist at the
Everglades Station January 15, 1929.
Dr. W. B. Tisdale was transferred from the position of Plant
Pathologist in Charge of the Tobacco Station at Quincy, to the
position of Plant Pathologist and Head of the Department of Plant
Pathology at the Main Station, January 1, 1929.
Howard Tompkins was appointed Clerk and Stenographer at
the Everglades Station August 6, 1928, and resigned September
30, 1928.
Ross F. Wadkins resigned as Laboratory Assistant at the
Tobacco Station June 30, 1929.
J. H. Wallace was appointed Assistant Agronomist at the Main
Station August 15, 1928, and resigned December 15, 1928.
John L. Wann was appointed temporary Assistant, Department
of Agricultural Economics, May 1, 1929.

SCOPE OF THE STATION WORK, JULY 1, 1928, TO JUNE 30, 1929
A list of the principal projects carried on during the year is given below, arranged according to depart-
ments. Page reference to a brief discussion of the work conducted under each project is made also.

AGI
E

Department Project
Numbe
BICULTURAL 73
ECONOMICS 91
103

104
121
123
134

AGRONOMY

r Name of Project P
Agricultural Survey of Some 500 Farms in the General Farming Region of Northwest Florida
A Study to Determine the Cost of Picking, Hauling and Packing of Florida Citrus Fruits......
A Study of the Cost of Transportation of Florida Citrus Fruits with Comparative Costs from
Other States and Foreign Countries ................. ...............................
An Economic Study of Dairy Farming in Florida .......................................
Cotton Grade and Staple Estimates and Primary Market Price Study ......................
A Study of Florida Truck Crop Competition............................................
Economic Study of the Pecan Industry in Florida .......................................

Peanut and Corn Fertilizer Experiments................................................
Plant Breeding- Peanuts ...... .....................................................
Pasture Experiments .................................................................
Lawn and Golf Grass Studies......................................................
Effect of Land-Plaster or Gypsum (CaSO4 2H20) on Hay and Seed Production of Peanut Vari-
eties ... ............................................................. .......
W inter Legume Studies .. ......................................................
Summer Cover Crop Studies ...........................................................
Crop Rotation Studies with Corn, Velvet Beans, Sweet Potatoes and Peanuts ...............
Variety Test W ork with Farm Crops....................................................
Sources of Nitrogen and Rates of Application of Nitrogen from the Different Sources as Top
Dressing for Oats ............. .................... ..............................
Green Manure Studies ...................................... ......................
Growth Behavior and Composition of Transplanted Bahia Grass and Bahia Grass under Pasture
C conditions ..... .................................. ..................................
Growth Behavior of Bahia Grass.....................................................
Improvement of Corn through Selection and Breeding ...................................
Effect of Time of Planting of Corn on Forage and Grain Yield ..........................
Crop Adaptation Tests ...............................................................
Fertilization of Pasture Grasses .....................................................
The Effect of Potash on the Yield and Quality of Peanuts ...............................

age
22
22

23
23
24
24
25

26
27
34
34

28
29
30
28
28

29
30

31
32
32
33
33
33
27

ANI
H

Department Project
Number

[MAL 61
USBANDRY 62
63
64
92
109

119
122
133
135
136
137
140

CHEMISTRY

COTTON INVESTI-
GATIONS

Name of Project

P

Types of Hemorrhagic Septicemia found in Florida ......................................
"L eeches" of H orses .................................................................
Use of Chlorine Gas in Treatment of Infectious Mastitis in Cattle .........................
Manson's Eyeworm of Poultry (Oxyspirura mansoni) .................................
K idney W orm of Swine ...................................... ......................
Test of High Protein in the Growth, Development and Production of Dairy Calves, Heifers
an d C ow s ........................................................................
Paralysis of the Dom estic Fowl .......................................................
The Cost of Wintering Steers Preparatory to Summer Fattening on Pasture.............
Deficiencies in Feeds Used in Cattle Rations...........................................
Soybean Silage for Dairy Cows .......................................................
Comparisons of Various Grazing Crops with Dry Lot Feeding for Pork Production.........
The Value of Grazing for Fattening Cattle in Beef Production ..........................
Relation of Conformation and Anatomy of the Dairy Cow to Her Milk and Butterfat Produc-
tion ................................. ..........................................

21 D ieback of Citrus ................................................................... 43
22 Determination of the Effect of Varying Amounts of Potash on the Composition and Yield and
Quality of the Crop ............................................................... 44
36 Determination of the Fertilizer Requirements of Satsuma Oranges ....................... 44
37 Determination of the Effect of Various Potash Carriers on Growth, Yield and Composition
of Crops ......................................................................... 45
38 Determination of the Mineral Constituents of Various Florida-Grown Cattle Feeds, as Com-
pared with Feeds Grown Farther North............................................. 48
66 Study of Fertilizer Requirements of Citrus Trees when Grown on Muck Soil................. 45
67 Composition of Crops as Influenced by Fertilization and Soil Types-Pecans .............. 48
94 Effect of various Fertilizer Formulas ................................................. 45
95 Concentrated Fertilizer Studies ....................................................... 46
96 Determination of the Effect of Green Manures on the Composition of the Soil............. 46
112 Effect of Various Fertilizer Treatments and of Soil Amendments on Tomatoes ............ 48

57 C otton B reading ..................................................................... 49
75 Boll W eevil Investigations ............................................................ 50

age
36
41
36
42
40

37
41
39
38
38
40
38

37

Department Project
Number

COTTON INVSETI-
GATIONS
(Continued)

ENTOMOLOGY

HOME
ECONOMICS

HORTICULTURE

Name of Project

Page

Cotton Rust ....................................................................... 51
Seedling Diseases of Cotton .......................................................... 51
Studies on Cotton W ilt ..... ......................................................... 52
Cotton Physiology-Nutrition and Growth............................................ 52

Velvet Bean Insects-Life History Studies and Control of the Velvet Bean Caterpillar ...... 53
Florida Flower Thrips ............................................................. 53
Root Knot Investigations ............................................................. 54
Introduction and Study of Beneficial Insects .......................................... 54
Larger Plant Bugs on Citrus and Truck Crops ....................................... 55
Studies of the Bean Jassid......................................... ................. 56
The Green Citrus Aphid (Aphis spiraecola) .......................................... 56
Control of Deciduous Fruit and Nut Crop Insects .................................... 57
Life History Studies of Pycnoscelus surinamensis L: the Roach which is the Intermediate
Host of Manson's Eyeworm ......................................................... 58

Determination and Identification of Organisms which Cause the Spoilage of Canned Vegeta-
bles in the South ................................................................. 59
Determination of whether Chlorophyll, Chlorophyll Alpha and Beta, the Petroleum Ether
Extracts of the Yellow Pigments of Alfalfa, can be Used as a Source of Vitamin A in
Animal Nutrition ................................................................. 59
A Study of Some of the Constituents of Citrus Fruits, Loquats, Roselle, and Guava: Pectin,
Oils, and Glucosides ................. .............................................. 60
The Determination of the Nutritional Status of Rural School Children in Five Representative
Counties in Florida .... ........................................................... 61
The Relation of Growth to Phosphorus, Calcium and Lipin Metabolism as Influenced by the
Thymus ...................................... ..................... ........... .. 62

Field Studies of the Diseases Affecting the Pecan, Including Control Measures ............ 65
Field Studies of the Insects Attacking the Pecan, Including Control Measures ............. 65
Variety Response of Pecans to Different Soil Types, Localities, Etc. ...................... 65

Project
Department Number

HORTICULTURE
(Continued)

PLANT
PATHOLOGY

Name of Project

P

Cooperative Fertilizer Tests in Pecan Orchards .........................................
Variety and Stock Tests of Pecan and Walnut Trees .....................................
Rejuvenation Experiments with Pecan Trees ............................................
V variety Test of Grapes ..............................................................
Propagating, Planting, and Fertilizing Tests with Tung-Oil Trees ........................
Observation and Testing of Various Citrus Hybrids .....................................
Testing of Native and Introduced Shrubs and Ornamentals and Methods of Their Propagation
Variety, Propagation and Planting Tests of Pear, Avocado, Japanese Persimmon, Fig and
O their F ruits ......................................................................
Variety Tests of Berries (Rubus spp.) ................ ................................
Cooperative Cover Crop Tests in Pecan Orchards ......................................
Tests of Different Stocks as Rootstocks for Satsuma Oranges ...........................
Phenological Studies on Truck Crops in Florida .......................................
Fundamental Physiology of Fruit Production ..........................................

Gum m ing of Citrus ..................................................................
A nthracnose ........................................................................
Melanose and Stem-End Rot of Citrus..................................................
D diseases of Pecan Trees ..............................................................
Bacterial Diseases of Solanaceous Plants...............................................
Seedbed Diseases of Truck Crops......................................................
Citrus Canker ......................................................................
Phom opsis of Eggplant ..............................................................
A avocado Scab ......................................................................
Avocado Fruit Spot .................................................................
Downy Mildew of Cucumber. ..........................................................
Bacterial Diseases of Cucurbits .......................................................
Citrus Scab .........................................................................
C itrus C anker .......................................................................
Downy M ildew of Cucurbits ...................................................... .....
D diseases of Potatoes .................................................................
C itrus B light ......................................................................
Straw berry D diseases .................................................................

'age
66
66
66
64
65
64
63

63
63
66
64
66
64

69
81
71
80
81
73
71
81
81
73
74
75
72
81
74
81
81
81

Department
PLANT
PATHOLOGY
(Continued)

CITRUS
EXPERIMENT
STATION

EVERGLADES
EXPERIMENT
STATION

TOBACCO
EXPERIMENT
STATION

Project
Numbe

114
115
116
118
126
127
128
129
130
131
132

26
34
35
83
102

84
85
86
87
88
89
90

25
33

117

r
r

Name of Project

Page

Asparagus Fern Survey ..........................-. ................................. 73
The Diseases of the Citrus Aphid .................................................... 72
Nailhead Rust of Tomatoes-Control .................................................. 75
Nailhead Rust of Tomatoes-Cause ................................................... 75
Corn Disease Investigations ........................................................... 79
Strawberry Diseases ................................................................. 76
Strawberry Anthracnose .............................................................. 76
Crimps or French Bud of Strawberries.......................... ................... 77
Investigation of Irish Potato Disease Known as Alternaria Tuber Spotting ............... 78
Potato Diseases ................ .................................................. 78
Late Blight Disease of Potato .......................................................... 79
Rhizoctonia Control ... ............................................................. 79

Citrus Progeny and Bud Selection.................... .......... ................ 82
Propagation Experiments with Citrus Plants of Various Kinds ......................... 82
Testing of Introduced and New Varieties and Hybrids of Citrus and Near-Citrus .......... 82
Cover Crop and Green Manure Studies in Citrus Groves ............................... 83
Citrus Variety Test, Including Rootstocks .............................................. 84

Forage, Truck and Field Crop Trials ................................................... 90
Fruit and Forest Tree Trials .......................................................... 90
Field Fertilizer Experiments ........................................................ 90
Insect Pests and Plant Diseases and Their Control ................................... 94
Soil Investigations ................................................................... 94
Drainage Studies ...................................................... .............. 95
Soils and Crop Studies, Including Rotation, Fertilizer and Cultural Practice Experiments 95

Field and Laboratory Studies of Tobacco Diseases ............ ...................... 97
Variety Tests of Cigar Wrapper Tobacco for Resistance to Black Shank (Phytophthora nico-
tianae Breda de Hann.) ............................................................. 98
Fertilizer Experiments with Shade Tobacco .. .................................... 101

Annual Report, 1929 13

REPORT OF BUSINESS MANAGER

Wilmon Newell, Director.

SIR: I submit the following report of the credits received and
expenditures vouchered out of various Experiment Station funds
for the year ending June 30, 1929.
Respectfully,
K. H. GRAHAM,
Business Manager.

MAIN EXPERIMENT STATION, 1928-1929
Receipts
Balance on hand July 1, 1928 .................... $ 14,044.11
State Appropriation '2 Biennium ................. 222,955.00
$236,999.11
Expenditures
Salaries ....................................... .$113,863.68
Labor ........................................... 22,826.77
Stationery and Office Supplies ..................... 2,106.08
Scientific Supplies ............................... 4,673.61
Feeding Stuffs .................................. 3,536.11
Sundry Supplies ................................ 3,450.45
Fertilizers ...................................... 2,659.90
Communication Service .......................... 1,498.60
Travel Expense ................................. 12,512.23
Transportation of Things ........................ 1,453.73
Publications .................................... 6,056.20
Heat, Light, Power ............................... 2,623.20
Furniture ...................................... 3,535.25
Library ........................................ 2,862.75
Scientific Equipment ............................ 5,720.07
Livestock ....................................... 451.23
Tools, Machinery, Appliances .................... 2,886.89
Buildings and Lands ............................ 2,042.90
Contingent ..................................... 419.01
Balance ............ :............................ 41,820.45
$236,999.11

Florida Agricultural Experiment Station

STATION INCIDENTAL FUND, 1928-1929
Receipts
Balance on hand July 1, 1928.................... $ 3,928.20
Receipts, 1928-1929 ............................. 20,357.47

$ 24,285.67

Expenditures
Salaries ......................................... 3,471.68
Labor ................ .......................... 2,118.42
Stationery and Office Supplies .................... 453.60
Scientific Supplies ............................... 105.52
Feeding Stuffs ................................. 6,630.91
Sundry Supplies ............................... 1,348.21
Fertilizers ..................................... 259.57
Communication Service .......................... 188.95
Travel Expense ................................. 721.95
Transportation of Things ........................ 326.71
Publications .................................... 7.60
Heat, Light, Power .............................. 1,193.74
Furniture ..................................... 115.40
Library ........................................ 13.00
Scientific Equipment .................. .......... 132.24
Livestock ...................................... 429.50
Tools, Machinery, Appliances .................... 861.01
Buildings and Land ............................. 469.04.
Contingent ..................................... 716.03
Balance ........................................ 4,722.59
$ 24,285.67

CITRUS EXPERIMENT STATION FUND, 1928-1929
Receipts
Balance on hand July 1, 1928 ......................$ 3,191.30
State Appropriation 1 Biennium .................. 15,100.00

Expenditures
Salaries ......................................$ 5,366.67
Labor ........................................ 2,250.33
Stationery and Office Supplies .................... 21.85
Scientific Supplies ............................. 660.14
Feeding Stuffs .................................. 454.56
Sundry Supplies ................................ 372.08
Fertilizers ..................................... 869.70
Communication Service .......................... 59.13
Travel Expense ................................. 145.55
Transportation of Things ........................ 79.25
Publications ................................... .00
Heat, Water, Light, Power ...................... 710.41
Furniture ............. ......................... 609.05
Library ............... .......... .. .......... .00
Scientific Equipment ............................ 920.67
Livestock ................................... .00
Tools, Machinery, Appliances........................ 168.96
Buildings and Land ............................. 990.54
Contingent ..................................... .00
Balance ........................................ 4,509.78

S1R 291 3

$ 18,291.30

$ 18,291.30

Annual Report, 1929 15

TOBACCO EXPERIMENT STATION FUND, 1928-1929
Receipts
Balance on hand July 1, 1928 .....................$ 326.05
State Appropriation Biennium .................. 14,950.00
$ 15,276.05

Expenditures
Salaries ........................................ $ 6,500.00
Labor ................ .......................... 2,504.39
Stationery and Office Supplies ..................... 28.05
Scientific Supplies ............................... 17.39
Feeding Stuffs .................................. 202.34
Sundry Supplies ................................ 792.65
Fertilizers ................. ................... 552.54
Communication Service .......................... 45.61
Travel Expense ................................. 477.83
Transportation of Things ........................ 133.25
Publications .................................... .00
Heat, Water, Light, Power ...................... 366.70
Furniture ...................................... 873.45
Library ........................................ 37.46
Scientific Equipment ............................. .00
Livestock .... .................................. .00
Tools, Machinery, Appliances ..................... 168.65
Buildings and Land ............................. 2,092.43
Contingent ...................................... 5.00
Balance .................. ...................... 478.31
$ 15,276.05

EVERGLADES EXPEfIMENT STATION FUND, 1928-1929
Receipts
Balance on hand July 1, 1928 .....................$ 993.92
State Appropriation % Biennium ................. 60,000.00
$ 60,993.92
Expenditures
Salaries ......................................$ 10,851.65
Labor ......................................... 11,009.43
Stationery and Office Supplies .................... 132.41
Scientific Supplies ............................... 375.61
Feeding Stuffs .................................. 403.23
Sundry Supplies ................................ 2,050.39
Fertilizers ..................................... 335.40
Communication Service .......................... 130.49
Travel Expense ................................ 1,463.41
Transportation of Things ........................ 323.12
Publications .................................... .00
Heat, W ater, Light, Power ....................... 1,062.75
Furniture ..................................... 1,047.69
Library ....................................... 156.27
Scientific Equipment ........................... 3,676.74
Livestock ....................................... .00
Tools, Machinery, Appliances ..................... 6,166.53
Buildings and Lands ............................. 21,402.42
Contingent ..................................... 360.42
B balance ........................................ 45.96
$ 60,993.92

Florida Agricultural Experiment Station

PUBLICATIONS

Wilmon Newell, Director.
SIR: I submit the following report of the Editorial and Mailing
Department for the fiscal year ending June 30, 1929.
Respectfully,
J. FRANCIS COOPER,
Editor.

BULLETIN EDITING
During the year the Experiment Station issued eight bulletins,
These amount to 586 pages, the largest number of pages of bul-
letin material printed in one year to date. Copy for these and for
the annual report was edited and proofread and the printing was
supervised by the Editors.
A list of the bulletins issued during tie year, with titles, pages
and number of copies of each, is given lere:
No. Title Pages Edition
199 Coconut Bud Rot in Florida ............ ....... 88 3,500
200 The Climate of Florida .......................... 212 15,000
201 Variety Tests of White Potatoes ................. 16 5,000
202 Cost of Handling Citrus Fruit from the Tree to the
Car in Florida ................................ 112 5,000
203 A Contribution to the Biology and Control of the
Green Citrus Aphid ........................... 48 4,000
204 Strawberries in Florida ......................... 48 10,000
205 The Japanese Persimmon in Florida.............. 40 15,000
206 Manson's Eyeworm of Poultry. ................... 22 8,000
SUMMARY OF BULLETINS
Following is a brief summary of the principal points covered
in the bulletins:
No. 199. Coconut Bud Rot in Florida. (James L. Seal, pp. 88,
Figs. 51.) Discusses the distribution and economic importance
of this trouble; describes the symptoms; relates what is known
as to the cause. Explains in detail the work done by the author
relating to the causal organism, its physiology and morphology.
Touches on the seasonal development and the control of the dis-
ease.
No. 200. The Climate of Florida. (A. J. Mitchell and M. R.
Ensign, pp. 212, Figs. 14.) Tells of the climate of Florida, men-

Annual Report, 1929

tioning records of severe cold waves, tropical storms, etc. Gives
the mean maximum and mean minimum temperatures, precipi-
tation records, and highest and lowest temperature records for
45 different points in Florida over a period of years. Lists dates
of first and last killing frosts annually, and gives comparative
monthly and annual data, maximum rainfall by months, average
number of days with rainfall, prevailing wind direction, etc.
No. 201. Variety Tests of White Potatoes. (L. O. Gratz, pp.
16, Figs. 0.) Explains how the Spaulding Rose No. 4 potato came
to be the one commonly used in the Hastings area. Relates results
of tests which prove other varieties better yielders.
No. 202. Cost of Handling Citrus Fruit From the Tree to the
Car in Florida. (H. G. Hamilton, pp. 112, Figs. 40.) Reports
results of a study of the cost of picking, hauling, packing and
loading citrus in Florida. The study covered two years, 1924-25
and 1925-26. Various costs are analyzed in detail for each year.
No. 203. A Contribution to the Biology and Control of the
Green Citrus Aphid, Aphis Spiraecola Patch. (Ralph L. Miller,
pp. 48, Figs. 18.) Describes the characteristics, history and dis-
tribution of the aphid. Lists the known host plants, some of them
for the first time. Gives results of observations on the occurrence
of winged forms. Describes the reactions of the aphid. Lists
and describes natural agencies tending to control the pest, and
gives methods for artificial control.
No. 204. Strawberries in Florida. (A. N. Brooks, J. R. Watson
and Harold Mowry, pp. 48, Figs. 14). Contains hints on the cul-
ture of strawberries, diseases and insects affecting them, and
control of the pests. Bears the first published account of the
organism which causes a disease of strawberries known as crimps.
No. 205. The Japanese Persimmon in Florida. (A. F. Camp
and Harold Mowry, pp. 40, Figs. 22.) Describes the character
and value of the fruit, with the distribution and possible adapta-
tion of the plant in Florida. Contains a guide to planting vari-
eties so that pollination will be secured. Describes each variety,
giving size, shape, color and texture of fruit, and the period when
the variety ripens.
No. 206. Manson's Eyeworn of Poultry. (D. A. Sanders, pp.
22, Figs. 3.) Gives the distribution, history, and anatomy of the
eyeworm. Describes experiments conducted by the author which
prove that a species of cockroach, Pycnoscelus surinamnensis, is
the intermediate host of the worm, and that the life cycle of the
worm cannot be completed in the chicken and the ground.

Florida Agricultural Experiment Station

LIST OF PRESS BULLETINS ISSUED
During the year seven new press bulletins were issued and six
were reprinted. As a usual thing, 2,000 copies of each were run
at a printing. The list follows:
No. Title Author.
408 Internal Parasites of Poultry .......................... D. A. Sanders
409 The Chinch Bug on St. Augustine Grass Lawns..... J. R. Watson and
H. E. Bratley
410 The Damp-Off Disease of Boston Ferns ...............Erdman West
411 Ammoniacal Copper Carbonates and Other Stainless
Fungicides ............... .................. ..Erdman West
412 Bordeaux Paste Treatment for Stem-End Decay of
Watermelons ............................... George F. Weber
413 Equipment for Spraying and Dusting Pecan Trees........ .R. E. Nolen
414 Pecan Scab Control .................................. R. E. Nolen
367 Double-Blossom of Blackberry (reprint).................G. F. Weber
377 Disinfecting Truck Crop Seeds with Corrosive Sublimate
(reprint) ................ ..................... ... G. F. W eber
389 Lawns in Florida (reprint) ............................W E. Stokes
399 Growing Annual Flowering Plants (reprint) ............. W. L. Floyd
400 Preparation of Bordeaux Mixture (reprint)..............G. F. Weber
401 Suggestions for Control of Root-Knot of Tobacco
(reprint) ........................................ W B. Tisdale
DISTRIBUTION OF BULLETINS
The distribution of bulletins and supplies is handled in the
mailing room, which is under the supervision of the Editor. Dur-
ing the year 53,000 copies of Experiment Station bulletins left the
mailing room, approximately 10,000 of them for libraries on the
exchange list, and the remainder for Florida farms and homes.
Thousands of press bulletins were sent out to papers and to in-
dividuals.
NEWS STORIES
The work of the Experiment Station receives excellent publicity
in Florida news and farm papers and in Southern and National
farm publications. The knowledge gained by its workers is thus
made available to the public throughout the year.
The Agricultural News Service, published weekly by the Agri-
cultural Extension Service, each week carries from three to six
stories about Experiment Station work or advice from the Sta-
tion's workers. This is reprinted largely in the newspapers and
somewhat in the farm papers of Florida.
In addition to the news and informational stories distributed
through the Agricultural News Service, information about the
Station and its work is disseminated through special stories to
news and farm papers. During this fiscal year 30 special stories
relating to the Experiment Station were sent to the state mail
service of the Associated Press, and were distributed by that
organization to its 48 member papers in Florida.

Annual Report, 1929

During the year 14 special stories relating to the Experiment
Station and its work were prepared by the Editors and submitted
to seven state and national farm publications, where they were
used. In addition, the Editor conducted a page each month in
three different state farm papers in which suggestions by Experi-
ment Station workers were used to a large extent. He also con-
ducted a farm page in the Sunday issue of one state daily news-
paper during the entire year. Copies of questions received and
answered by Experiment Station workers were an important fea-
ture of this page each Sunday.

RADIO
With the opening of Radio Station WRUF at the University of
Florida, agricultural programs were put on the air regularly.
From October 1 to November 10, 1928, the agricultural program
covered 15 minutes daily (except Sunday) ; from November 11
until the end of the fiscal year, 30 minutes daily. During the first
41 days members of the staff appeared on the program daily, while
for the remainder of the year they appeared every other day.
United States Department of Agriculture material, selected by the
Editors as suitable for Florida, was broadcast on the days when
staff members did not appear. During the nine months October 1,
1928, to June 30, 1929, 58 radio talks were given by 24 different
members of the Experiment Station staff. In addition, hundreds
of questions from Florida residents and answers by Experiment
Station workers were read.
The Editors planned the programs, secured and edited copies
of talks by staff members, supervised the broadcasting of the
agricultural material, and read the questions and answers and
other material.
MISCELLANEOUS
A number of pictures not accompanied by special stories were
sent to farm papers and to syndicates. All of them got Florida
distribution and some received national circulation.
Assistance is always gladly rendered by the Editors to mem-
bers of the staff who are preparing articles for publication in
journals or elsewhere.
The Editors devote approximately one-half of their time to
work for the Agricultural Extension Service, leaving only one-
half for Experiment Station work. The Editor spent 10 days near
the end of the fiscal year at Orlando in connection with the Medi-
terranean fruit fly eradication work of the State Plant Board.

Florida Agricultural Experiment Station

LIBRARY

Wilmon Newell, Director.
SIR: I submit the following report of the Library for the fiscal
year ending June 30, 1929.
Respectfully,
IDA KEELING CRESAP,
Librarian.

The work of the Library for the present fiscal year has been
greatly handicapped by the restriction order regarding expen-
ditures issued in December. Owing to this, only a limited amount
of binding could be done for the year; relatively few accessions
have been made since that date and, although many new peri-
odicals or journals were greatly needed, no new subscriptions have
been placed.
To the dictionary card catalog 11,576 cards have been added.
This does not include those cards purchased from the Library of
Congress. These latter form a complete cross-index to all the
literature published by the United States Department of Agri-
culture. With this, the cataloging done in the Library, the Expe-
riment Station Record and the Agricultural Index, practically
all the material in the Library is quickly made available. There
were 496 new books added to the shelf, by purchase, gift and
exchange. The number of serials, continuations and pamphlets
will aggregate several thousand additions.
Most of the research study is done in the Library. No loans
are made to students. Nevertheless, 1,340 loans to staff and fac-
ulty were made this year-this being, by several hundred, the
largest number of loans ever made in one year. An unprecedented
use of the reading room is recorded, although no attempt was
made to check the exact number.
Shelf space has not been increased for the past two years.
There is now floor space for only one more bookstack and the
addition of this will relieve the crowded condition of the shelves
but slightly. The Library now contains 6,308 bound volumes,
besides thousands of unbound documents and a collection of scien-

Annual Report, 1929 21

tific periodicals and journals, in many instances, impossible to
duplicate in any other Southern state.
Librarians of the United States Department of Agriculture,
the Library of Congress, Harvard University, and many others,
have extended to us the privilege of inter-library loans. This has
given us an almost unlimited field to draw upon, as well as access
to many rare and invaluable books.
The Librarian has continued her research in agricultural litera-
ture throughout the year and has also worked towards securing
rural county library service for the state.

LIBRARY STATISTICS, 1928-1929
Number bound volumes ........................................ 6,308
Number new volumes added by gift, purchases and exchange........ 496
Number volumes sent to bindery ................................ 226
Number loans to staff and faculty................................ 1,340
Number books borrowed from other libraries ...................... 122
Number cards typed ........................................... 11,576

Florida Agricultural Experiment Station

AGRICULTURAL ECONOMICS

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Agri-
cultural Economics for the fiscal year ending June 30, 1929.
Respectfully,
C. V. NOBLE,
Agricultural Economist.

SURVEY OF 500 FARMS IN THE GENERAL FARMING
REGION OF NORTHWEST FLORIDA
(Purnell Project No. 73)
Complete summaries were made of 499 farm records for 1925
and each farmer who furnished a record was returned a summary
of the results from all farms together with the figures from his
own farm for comparative purposes.
Since 1925 was one of the best years that northwest Florida
had experienced for a long period, both as to yields and prices of
its leading crops, it was thought wise to take records from a rep-
resentative sample of the same farms for the year 1928 which
was a poor year. Records for 1928 were taken of approximately
100 of the same farms, operated by the same farmers, as were
surveyed for 1925. This was done in order to see what effect, if
any, the difference in financial returns from the farm business for
different years would have on the interpretation of farm organi-
zation. These records have been carefully checked and are being
put into shape at the present time for summarization. With the
comparative records for the two years, it is believed that the inter-
pretations will be more complete.
It is planned to complete this project as rapidly as possible.

A STUDY OF THE COST OF PICKING, HAULING AND PACK-
ING FLORIDA CITRUS FRUITS
(Purnell Project No. 91)
Early in the year the tabulations and the statistical work on
this project were completed. A field trip was made to study fur-

Annual Report, 1929

their pre-cooling operations and the study has been organized and
prepared for publication.
Bulletin 202 of this Station, "Cost of Handling Citrus Fruit
from the Tree to the Car in Florida", which is now in print, gives
a complete report of the work under this project.

A STUDY OF THE COST OF TRANSPORTATION OF FLORIDA
CITRUS FRUITS WITH COMPARATIVE COSTS FROM
OTHER STATES AND FOREIGN COUNTRIES
(Purnell Project No. 103)
Tabulations of comparative transportation costs from various
citrus producing areas to the principal markets of the United
States have been completed. Charts have been prepared to show
the freight rates per ton-mile from each of these areas; the index
numbers of freight rates on citrus fruits, other than lemons, from
California and from Florida since 1900; the relation of Florida
oranges and grapefruit prices to the general price level, and to
freight rates since 1910. A study has been made of the methods
of shipping citrus fruits, with the comparative cost of each
method.
The work has been organized and the preliminary draft written.
Studies of water transportation costs from the principal citrus
producing areas to a number of world markets remain to be com-
pleted. It is hoped that the project can be completed and pub-
lished during this year.

AN ECONOMIC STUDY OF DAIRY FARMING IN FLORIDA
(Purnell Project No. 104)

Work on this project was started in December, 1927. To date,
all records have been checked and copied.
On the Orlando, St. Petersburg and Tampa areas the following
tabulations have been made:
Milk and its products sold and used on the farm.
Livestock.
Feeds have been classified; costs of various kinds, and to what
they were fed.
Home grown feed and to what fed.
Summary of cost of milk production.
Summary of cost of raising heifers.
Summary for the farm.

Florida Agricultural Experiment Station

A summary for all farms and for the ten best farms, with the
comparative figures for the farm in question, was sent to each
cooperator.
About two-thirds of the work enumerated above was completed
for the farms in the Jacksonville and Ocala areas. Feed tabula-
tions and milk tabulations have been copied for the Miami area,
but not checked.
Completion of the summaries is expected during the year. In-
terpretation of the data will be the principal line of work.

COTTON GRADE AND STAPLE ESTIMATES AND PRIMARY
MARKET PRICE STUDY
(Purnell Project No. 121)
Work on this project was started on July 15, 1928. It is in
cooperation with the Federal Bureau of Agricultural Economics
and is a part of the comprehensive study being made of the cotton
area by that bureau.
Samples were taken of each bale of cotton ginned at five gins
located at Lake City, Madison, Tallahassee, Malone and Grace-
ville, Florida, respectively. These samples were sent to Atlanta,
Ga., for federal classification as to grade and staple.
Primary market price studies were made at the Tallahassee,
Malone and Graceville gins.
Yield-quality studies were made of the cotton ginned at the
Graceville and Tallahassee gins, by following back each bale
ginned, where practicable, to the producer's farm and obtaining
production methods, yields, etc., on each farm. All of these data,
with the exception of the Tallahassee yield-quality data, have been
summarized and forwarded to the Bureau of Agricultural Eco-
nomics as the Florida contribution toward their study.
It was decided not to continue this cooperative project another
year, because of lack of funds.

A STUDY OF FLORIDA TRUCK CROP COMPETITION
(Purnell Project No. 123)
Work on this project was begun in December, 1928. Since that
time compilations have been made by weeks of the carlot ship-
ments of each of Florida's important truck crops for the five-year
season ending 1928-1929. These data from Florida are compared
with each competing state and foreign country. Work is started
in charting these data in order that they may be more easily
interpreted.

Annual Report, 1929

Permission was obtained from each of the railroads entering
Florida to secure their records of carlot shipments by Florida
shipping points for each truck crop. Work is well under way in
gathering and compiling these data. The purpose of this phase of
the study is to bring out the sectional competition in Florida for
its important truck crops.

ECONOMIC STUDY OF THE PECAN INDUSTRY IN FLORIDA
(Purnell Project No. 134)
This project is in cooperation with the United States Depart-
ment of Agriculture, Bureau of Agricultural Economics and the
Department of Agricultural Economics, Teaching Division, College
of Agriculture, University of Florida. It was an emergency
project, due to the fact that the Teaching Division, which was to
handle all cooperative work on this project for Florida, had its
state funds for the year materially reduced and found itself unable
to finance the work.
A total of 78 records were taken covering the pecan industry
of individual producers in the two principal areas in Florida cen-
tering at Monticello and Campville, respectively. Copies of all
records have been retained for independent interpretation by this
institution. The originals have been forwarded to the Bureau of
Agricultural Economics for use in the general study of the pecan
industry in the states of South Carolina, Mississippi, Alabama,
Georgia and Florida.
It is planned to have a thorough analysis and interpretation of
these 78 records made by a graduate student during the coming
year. This work is supplemental to that performed by the federal
men and a separate publication of the Florida results is not ex-
pected to be made.

Florida Agricultural Experiment Station

AGRONOMY

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Agron-
omy for the fiscal year ending June 30, 1929.
Respectfully,
W. E. STOKES,
Agronomist.

PEANUT AND CORN FERTILIZER EXPERIMENTS
(Hatch Project No. 16)
Nine years' experimental work (1918-26 inclusive) on the fer-
tilization of Spanish peanuts with single elements (N, P, K) with
and without lime (CaCO3) gave no profitable increases in yield on
Norfolk sand. The lime actually materially decreased the yield.
This phase of the project has been discontinued.
Four years' (1922-23-24-26) experimental work on the fertili-
zation of Spanish peanuts on Norfolk sandy land with single ele-
ments, combinations of two and three elements with and without
land plaster (CaSO4 2 H20) gave a slight increase in yield from
certain elements and combinations and showed a slight response
from the use of land plaster alone and in combination with certain
elements, but in no case were increases great enough to be profit-
able. This experiment has been discontinued.
A Spanish peanut fertilizer experiment is now in progress
(started 1928) on Norfolk sandy land and this experiment is
arranged to give information on the effect of varying amounts
of a complete fertilizer of two analyses (2-8-5 and 4-8-5) on the
yield of peanuts, and to give the effect of varying the analysis of
a 600 pound per acre application on yield. Both phases of this
fertilizer experiment are carried out in such a way as to get at
the effect of peanut vine removal on yield. Results to date show
no profitable increases in yield.
Peanut fertilizer experiments in Jackson County, conducted
for two years (1927-28 inclusive), are now inactive due to lack
of funds. This work showed a slight profit from the use of 400
pounds per acre of a 3-9-3 and a 1-12-5 fertilizer.

Annual Report, 1929

The corn fertilizer experimental work consists of testing sources
of nitrogen and rates of application of nitrogen fertilizer for corn.
Sources of nitrogen test work is carried on with and without
phosphate and potash on corn after winter legumes as well as on
corn not following winter legumes.
Other phases of this work concern the testing of complete fer-
tilizers of varying analysis with and without side-dressings of
nitrogen. Up to date the most profitable yields of corn have been
obtained when winter legumes (hairy vetch and Austrian peas)
were turned under preceding the corn crop. Additions of com-
mercial nitrogen to corn following the turning under of satisfac-
tory crops of winter legumes has not been found necessary or
profitable.
Where corn does not follow a winter legume a side application
of 100 pounds per acre of some quick-acting soluble nitrogenous
fertilizer like nitrate of soda, sulfate of ammonia or calcium ni-
trate, has been found the most profitable fertilizer on the average.
Complete fertilizers to corn have not been found profitable thus
far except on flatwoods soil of the Portsmouth series. Experi-
ments have not been extended to cover flatwoods soils of other
series.
PLANT BREEDING-PEANUTS
(Hatch Project No. 20)
Seven strains of white Spanish peanuts selected at this Station
are being increased this year. In addition, one selection from the
Texas Station and one from the Bureau of Plant Industry, United
States Department of Agriculture, are growing in comparison
with our own strains this season. A number of controlled crosses
were made in the summer of 1928 and in the spring of 1929. Some
of the first crosses are now well along in the second generation and
promise some very interesting and valuable results.

THE EFFECT OF POTASH ON THE YIELD AND QUALITY
OF PEANUTS
(State Project No. 138)
This is a cooperative project with the Agricultural and Scien-
tific Bureau of N. V. Potash Export My. of Amsterdam, Holland,
through their American representative. Thirty-five different
potash formulas are being tested on Spanish peanuts. The field
work was begun in May, 1929, and will be carried on according
to agreement for a period of at least three years. A very satis-

Florida Agricultural Experiment Station

factory stand of peanuts was obtained on all plots but no differ-
ence is noted, thus far, in top growth.

EFFECT OF LAND-PLASTER OR GYPSUM (CaSO42H20) ON
HAY AND SEED PRODUCTION OF PEANUT VARIETIES
(Hatch Project No. 43)
Since 1923 a study of the effect of land-plaster on several kinds
of peanuts grown on Norfolk sandy soil has been in progress.
Data show that when land-plaster is used on peanuts grown year
after year on the same land the first tendency is toward increased
yield of nuts of all varieties used except the Virginia runner, while
after about the third year the yield of nuts of all varieties studied
except the Jumbo is decreased, to the point of unprofitableness.
Where peanuts are being grown on a different area each year
land-plaster increased the yield of nuts of all varieties used except
the Virginia runner to the point where some profit was gotten.
This experiment is not being conducted for the season of 1929,
due to the release of part of the experimental area to the Artillery
Unit of the University.

CROP ROTATION STUDIES WITH CORN, VELVET BEANS,
SWEET POTATOES, AND PEANUTS
(Hatch Project No. 55)
This six-phase crop rotation experiment was temporarily
brought to a close at the end of the crop season 1928, due to a
shortage of funds. The land is now idle, growing weeds, but the
experiment will be active starting the fall of 1929 if funds permit.

VARIETY TEST WORK WITH FARM CROPS
(Hatch Project No. 56)
Variety test work with the following crops was conducted dur-
ing the year: corn, cowpeas, peanuts, oats, soybeans, sorghum,
millet and sugarcane.
Mixed plantings of cowpeas and soybeans were also compared
to pure plantings of these crops. A date of planting test of soy-
beans was conducted particularly to try to find out whether or not
this might influence seed production, since it has been found diffi-
cult to obtain satisfactory seed yields.

Annual Report, 1929

SOURCES OF NITROGEN AND RATES OF APPLICATION
OF NITROGEN FROM THE DIFFERENT SOURCES AS
TOP-DRESSING FOR OATS
(State Project No. 97)
This experiment is carried on in such a way as to give infor-
mation on the effect of the different sources of nitrogen as a top-
dressing on the yield of both October and November planted oats,
as well as the effect of different rates of nitrogen top-dressings
on yield.
This year only one source of nitrogen could be tested as to the
effect of rate of application on yield.
In the sources tests nitrate of soda gave the greatest increase
in yield in both October and November planted oats.
In the rate test nitrate of soda was applied as follows: 100, 200,
300 and 400 pounds per acre respectively. With each increment
of nitrate of soda the oat yield increased, but the 100 pound per
acre top-dressing proved the most profitable.

WINTER LEGUME STUDIES
(Hatch Project No. 53)
A rate and date of planting test of hairy vetch, monantha vetch
and Austrian winter peas was conducted during the winter of 1928-
1929. Late September planting gave highest yields of monontha
vetch, early October the highest for hairy vetch, and late October
for Austrian peas. Three rates of planting were used, 15, 20 and
30 pounds per acre for both vetches and 25, 30 and 35 pounds for
Austrian peas. The heavier rates of seeding gave the higher
yields in all cases.
Corn was planted after the variety fertility test of winter
legumes reported in 1928 annual report. The highest yields were
obtained after hairy vetch with monantha vetch and Austrian
peas following in the order given. The yield of corn after oats
was less than one-half that after either of the vetches. The plats
were planted to the same winter legumes last fall and the yields
in each case were nearly 50% higher than the previous year.
Sweet clover, which was practically a failure in the 1927-28 test,
gave very satisfactory yields when manure, phosphate and lime
were used. The higher yield of all legumes is possibly due in part
to better inoculation.
The cooperative tests in Central, North and West Florida are
being continued on a larger scale with gratifying results.

Florida Agricultural Experiment Station

A date of planting test of corn after hairy vetch and Austrian
peas turned at different dates was started in the spring of 1929.
The winter legumes were turned under February 18, March 6,
and March 21, and the corn planted 10 days later, in each case.
The yields of the legumes were determined before turning under.
The yields of both legumes taken March 6 were more than double
the yields taken February 18. Corn yields will be taken from
these plots in the fall of 1929.

SUMMER COVER CROP STUDIES
(Hatch Project No. 54)
The work on this project at the Main Experiment Station at
Gainesville is temporarily held up since the crop season of 1928,
due to having to release the area used for this experiment to the
University Artillery Unit. Up to date Crotalaria striata had proved
the most satisfactory summer cover crop of any in the test.
The work is in full force on these studies at the Citrus Branch
Station at Lake Alfred. A report of progress will be found under
Project No. 83, at that Station.

GREEN MANURE STUDIES
(Hatch Project No. 98)
Part of the work on the composition and nitrification studies
on Crotalaria striata has been completed and sent to Soil Science
for publication, and will appear in this journal in the near future.
A direct correlation was found between the composition of the
whole plant and each of its parts and the rate of decomposition
of the same when incorporated with the soil.
The relation, or ratio, between the nitrogen and carbohydrates
in the plant or any of its parts was directly associated with the
rate of decomposition in the soil. The variation in the percentage
of cellulose and lignin in the plant was also a factor affecting its
decomposition. In the early growth stages with a narrow ratio
between carbohydrates and nitrogen and a lower percentage of
cellulose and lignin, the decomposition of the plant proceeded more
rapidly when incorporated with the soil. In the later growth
stages when the ratio between carbohydrates and nitrogen was
wider, and the percentage of lignin and cellulose was higher, de-
composition proceeded more slowly. The results of these findings
appear to have a direct bearing on the turning under of green
manures in field and grove practices.

Annual Report, 1929

LYSIMETER STUDIES
The continuous growing of crops in lysimeters decreased the
amount of leachings from the soils in these containers approx-
imately 20%. The decomposing green manures furnished a con-
tinuous supply of nitrogen to the growing crop. A large green
manure crop turned under with no crop planted thereafter in-
creased the amount of plant nutrients leached. When a crop was
planted some time after the green manure crop was turned under,
the plant nutrients were utilized by the growing crop and the
leaching of such plant nutrients from the soil decreased.

GROWTH BEHAVIOR AND COMPOSITION OF TRANS-
PLANTED BAHIA GRASS AND BAHIA GRASS
UNDER PASTURE CONDITIONS
(Hatch Project No. 99)
The results of studies made on transplanted Bahia grass have
been prepared in the form of a technical bulletin from this depart-
ment. A summary of these results in brief are as follows:
Bahia plants cut frequently remain in a more vegetative growth
condition throughout the growing season, i. e., a narrow carbo-
hydrate-nitrogen ratio is maintained in the top growth of such
plants which is associated with the production of more vegetative
plant parts.
The residual leaf area on the plants not removed by grazing
or cutting is sufficient for the elaboration of organic foods for
vegetative growth. This more vegetative growth condition of
these plants resulted in a more horizontal growth of stolons and
a better sod formation. The following spring an earlier and more
vigorous top growth was produced from such plants than from
plants grown to maturity the preceding season.
Plants permitted to grow to maturity produced an upright
growth of stolons in the form of seed stems which resulted in a
poor sod formation. Little vegetative growth was produced from
such plants after late maturity of the plants. The more mature
growth stages were associated with a wide carbohydrate-nitrogen
ratio in the top growth.
Plants grown to maturity produced a larger and heavier stolon
and root growth but stolons and roots of plants cut frequently
showed a gradual increase in growth and weight of these plant
parts.
Organic food in the stolons of roots of plants grown to maturity
were greater in percentage and quantity than in similar plant

Florida Agricultural Experiment Station

parts of plants cut frequently but the percentage and quantity of
such foods in the latter appeared sufficient for continuous vege-
tative growth throughout the season.
Decrease in percentage and quantity of organic food occurred
in the storage organs of the plants during vigorous vegetative
top growth, but the leaf area of the plants appeared to be suffi-
cient for the elaboration of such foods to replenish the losses sus-
tained by the storage parts of the plants.
After the top growth was cut in the seed stage, the plants again
produced a new vegetative top growth but where no such cutting
was made very little vegetative top growth took place.

GROWTH BEHAVIOR OF BAHIA GRASS
(Hatch Project No. 100)
Bahia plants grown to maturity and not cut during the growing
season produced larger and heavier stolons and roots than similar
plants that were grazed. The stolons of ungrazed plants produced
more of an upright growth in the form of seed stems, leaving
vacant spaces between the plants. This resulted in a poor sod
formation in comparison to sods formed from plants subjected to
frequent grazing. The vacant spaces between the plants in the
former were soon covered with a rank weed growth which did not
take place in case of the latter.
When plants not grazed for two seasons were mowed frequently
they again produced more of a vegetative growth and formed a
denser sod, which in turn crowded out weed growth. A larger
yield of top growth was produced from these plants than from
an equal area of plants that were grazed continuously the pre-
vious seasons.

IMPROVEMENT OF CORN THROUGH SELECTION AND
BREEDING
(Purnell Project No. 105)
The self-pollinated ears harvested in the fall of 1928 repre-
sented 230 lines selfed two years and 2,500 lines selfed one year.
This season 75 second year selfs and 800 first year selfs were
planted in the field. Self-pollinations were made in most of these
lines. In addition about 1,000 plants have been selfed in each of
three varieties.
Duplicated ear-row tests were planted this spring of 100 ears
from each of two varieties.

Annual Report, 1929

The yield test includes the popular corn varieties of the state
and adjacent states.

EFFECT OF TIME OF PLANTING OF CORN ON FORAGE
AND GRAIN YIELD
(State Project No. 106)
The usual date for planting field corn in North Florida is some
time in March or early April. Some folks have suggested and
even advocated later planting. In order to have definite infor-
mation, monthly plantings of an early and a late maturing variety
of corn have been made for the past three years, starting plantings
in February and running through June. This year the February
planting of the late maturing variety gave highest ear corn and
silage yields, also the February planting of the early maturing
variety gave higher yields than did later plantings of this variety.
The June plantings of both varieties of corn were complete failures
due to ravages of bud worms.

CROP ADAPTATION TESTS
(Hatch Project No. 107)
*
This project has to do with the testing of plants sent to the
Agronomy Department by the United States Forage Crops Office
with whom we cooperate. It so happens that a great many new
plants from various parts of the world are sent to us for testing
under Florida conditions.
As a result of this work in rather recent years the following
plants have been found well suited to Florida: Napier grass
(Pennisetum purpureum), Bahia grass (Paspalum notatum),
Centipede grass (Eremochloa ophiuroides), Crotalaria striata
and Crotalaria spectabilis (formerly called C. sericea).
This season several unknown species of Crotalaria have been
identified. Two promising varieties of pigeon pea (Cajanus
cajan) have been planted in increase plats for the purpose of
obtaining seed yield and the forage value of the crop.
The plant introduction garden contains many new legumes,
grass and fibre plants that are being closely observed.

FERTILIZATION OF PASTURE GRASSES
(Hatch Project No. 120)
A partial report on the differences in yield and the percentage
and quantity of nitrogen in the top growth of differently treated
plants can be stated as follows:

Florida Agricultural Experiment Station

In the case of Bahia grass cut frequently there was a progres-
sive increase in the green and dry weight of top growth, weight
of nitrogen and percentage of nitrogen from the differently
treated plots in the following order: nitrate of soda and water;
nitrate of soda; water only; no treatment. The Bahia grass per-
mitted to grow to maturity in all cases showed a progressive de-
crease in percentage of nitrogen even when heavily fertilized
with nitrate of soda. Although no carbohydrate analyses are
available at the present writing, the difference in variation in the
percentage of nitrogen between the top growth of the grasses cut
frequently and that of grasses allowed to grow to maturity, indi-
cates a narrow carbohydrate-nitrogen ratio in the former and a
gradual widening of this ratio in the latter.
Carpet and centipede grasses cut frequently and given different
applications of nitrate of soda and water, showed a progressive
increase in production of top growth, weight of nitrogen and per-
centage of nitrogen, in the order of the treatments given: no
treatment; water; nitrate of soda; nitrate of soda and water.
High nitrogen was found to be associated with a more vegetative
growth condition and low nitrogen with the production of more
reproductive plant parts and a decrease in vegetative growth.
Frequent cutting or grazing appears to be essential for pro-
duction of a more vegetative growth of prostrate growing pasture
grasses for grazing purposes, even when such grasses are heavily
fertilized. More detailed information on the results of this work
will be given when further chemical analyses are completed.

PASTURE EXPERIMENTS
(Hatch Project No. 27)
The work of testing the influence of nitrogen fertilizers on the
yield and protein content of pasture grasses has been continued
and enlarged. The results obtained show a slight increase in pro-
tein content in the grass from the nitrogen treated plots over that
from the untreated plots. The yield of the nitrogen treated plots
was about double that of the untreated plots. The tests are being
applied to plots which are mowed every 10, 20 and 30 days re-
spectively, simulating close, medium and light grazing.
The pasture grazing experiments have given very gratifying
results. The experiment consisted of grazing 500-pound native
range steers at the rate of one head per acre. A gain of 260
pounds per steer was made in 210 days when rotated from Bahia
to a mixture of Bahia, Bermuda, carpet and Dallis grasses. After

Annual Report, 1929 35

paying for the fertilizer and rent of 50c per head per month the
steers returned a profit of $7.82 per steer or per acre.
Bahia, carpet, Bermuda and centipede continue to be the out-
standing pasture grasses.

LAWN AND GOLF GRASS STUDIES1
(Hatch Project No. 42)
A bulletin on lawn grasses for Florida has been prepared for
publication and will be in print in the near future.
The work is being continued as reported last year. Poa bulbosa
has failed to grow and apparently is of no value in Florida as a
winter grass, due to failure to give a volunteer crop.
Interest in the turf work is increasing and more funds are
necessary to enlarge and carry on the type of work pertinent to
the problems of golf clubs in Florida.
iFunds for the golf grass studies are furnished by the United States Golf
Association.

Florida Agricultural Experiment Station

ANIMAL HUSBANDRY
Wilmon Newell, Director.
SIR: I submit the following report of the Department of Ani-
mal Husbandry for the fiscal year ending June 30, 1929.
Respectfully,
A. L. SHEALY,
Head of Department.

The Department of Animal Husbandry was created on July 1,
1928, by the combination of the former departments of Animal
Industry and Veterinary Science. During the year the work of
the former department of Animal Industry has been adjusted
and enlarged and the work of the former department of Veteri-
nary Science has been carried forward about the same as for the
previous year. Several projects have been closed and new, more
promising lines of work initiated.

TYPES OF HEMORRHAGIC SEPTICEMIA FOUND IN
FLORIDA
(State Project No. 61)
For the past three years work on other diseases of greater
economic importance has made it impossible for active research
work to be conducted on this project. Until additional workers
can be secured the project will be inactive.

USE OF CHLORINE GAS IN TREATMENT OF INFECTIOUS
MASTITIS IN CATTLE
(State Project No. 63)
Due to the fact that no members of this department are engaged
in the actual practice of veterinary medicine, and since there are
too few cases of mastitis in the Experiment Station dairy herd in
which this treatment could be administered, we would recommend
that work on this project be ended. We have developed a technic
which might be worthy of consideration, but we have never been
able to find affected animals in numbers sufficient for us to treat
and expect to receive information which could be considered
conclusive,

Annual Report, 1929

RELATION OF CONFORMATION AND ANATOMY OF THE
DAIRY COW TO HER MILK AND BUTTERFAT
PRODUCTION
(State Project No. 140)
Ante- and post-mortem measurements of one Guernsey and
three Jersey cows have been secured on this project and complete
copies of the original data submitted to W. W. Swett of the Bureau
of Dairy Industry, United States Department of Agriculture, who
is a leader in this cooperative project. Only such animals as have

Fig. 1.-One of the cows slaughtered in the study of the relation of con-
formation and anatomy to milk and butterfat production. External and
internal measurements of all parts of her body were made. The cow was
11 years old when slaughtered, and records were available on each of her
nine complete lactation periods.

passed their period of usefulness in the herd are used in this study.
As a separate part of this work, feeding studies in connection with
the digestive system of these cattle are being made by members
of this department.

TEST OF HIGH PROTEIN IN THE GROWTH, DEVELOPMENT
AND PRODUCTION OF DAIRY CALVES, HEIFERS
AND COWS
(Hatch Project No. 109)
On account of the limited number of animals available for work
under this project, it has been decided to discontinue the project.

Florida Agricultural Experiment Station

The feeding of the high protein ration, without green feed, has
resulted in "shy breeding" on the part of the young heifers used
in the experiment. Many of these heifers had been bred four and
five times without conception and their replacement with other
registered Jersey heifers from the dairy herd was deemed in-
advisable at this time.
SOYBEAN SILAGE FOR DAIRY COWS
(Hatch Project No. 135)
Otootan soybeans are being grown on slightly over six acres of
land, and the smaller silo at the dairy barn is being reserved for
use in conjunction with the investigation of soybean silage during
the coming winter. The first of a series of feeding trials with this
silage will then be conducted with dairy cattle.

DEFICIENCIES IN FEEDS USED IN CATTLE RATIONS
(Purnell Project No. 133)
A study of the deficiencies in feed associated with the condition
known as "salt sick" has been begun. Contacts have been made
with 58 head of cattle on 11 farms where this particular condition
exists. In connection with this work samples of the native pasture
grass (wire grass) have been secured from unfertilized pastures
on each of these farms to be used as a basis of comparison. Sim-
ilar studies have been made on seven farms where the condition
known as "salt sick" has never occurred in the memories of the
present owners. The services of Dr. W. M. Neal have been secured
and a laboratory is being equipped at present to continue certain
phases of this study. Arrangements have been made to secure
feed from a severely affected farm in an investigation that is to
be begun during the year 1929. Examination has been made of
the feces of a number of affected cattle in order to observe any
relationship between intestinal parasites and the condition known
as "salt sick."
(Note.-This project replaces former State Project No. 65.)

THE VALUE OF GRAZING FOR FATTENING CATTLE IN
BEEF PRODUCTION
(Hatch Project No. 137)
Twenty steers were divided into four lots of five each and each
lot was turned on a pasture plot on March 13. The four pasture
lots being grazed at this time by these steers are (1) carpet grass,
(2) Bermuda grass, (3) Bahia grass and (4) a mixture of carpet,

Annual Report, 1929

Bermuda, Bahia and Dallis grasses. These steers were weighed on
three consecutive days at the beginning of the test and are being
weighed on two consecutive days each month during the progress
of the experiment. A steady gain has been made by each steer
since they were turned into the pastures. The condition of the
pasture relative to the amount of grazing available during the
grazing season is being recorded.

THE COST OF WINTERING STEERS PREPARATORY TO
SUMMER FATTENING ON PASTURE
(State Project No. 122)
Twenty steers were put on test December 8, 1928, and fed until
March 9, 1929-a total of 91 days. The feeds used in this experi-
ment were beggarweed hay and peanut hay as roughage, and a
mixture of equal parts ground snap corn and velvet bean meal as
concentrates. The hay was purchased at $25.00 per ton, while the
ground snap corn and velvet bean meal cost $35.00 per ton. The
steers consumed a daily average of 7.7 pounds of hay and 2.41
pounds of concentrates per head. A ration slightly above a main-
tenance ration was determined so that there would be no appre-
ciable fattening during the experiment, yet a slight gain was
desired. It was found that the above mentioned amounts pro-
duced such a condition. Based upon the market price paid for the
feed when same was purchased for use in the experiment and
upon the amount of feed consumed during the course of the ex-
periment it was found that the total daily cost for feed per steer
was as follows:
7.7 lbs. hay at $25.00 per ton ...........................$ .096
2.41 lbs. ground snap corn and velvet bean meal equal parts
at $35.00 per ton ................................... 042
Total cost for feed per steer per day ................... $ .138

The 20 steers made a total gain of 610 pounds, or an average
gain of 30.5 pounds per steer during the experiment. The aver-
age daily gain per steer was .33 pounds. As stated above, only
a slight gain was desired, since the object of the experiment was
to determine how cheaply and practically steers could be wintered
on native grown feeds. All the steers were fed identical rations,
since it was impossible to get whole velvet beans at the time the
experiment was commenced.

Florida Agricultural Experiment Station

COMPARISONS OF VARIOUS GRAZING CROPS WITH DRY
LOT FEEDING FOR PORK PRODUCTION
(Hatch Project No. 136)
Crops of (1) peanuts and corn and (2) sweet potatoes are being
grown for use in feeding tests in which comparisons will be made
in the value of these crops for swine production. Shotes of uni-
form size and breeding were raised on the Experiment station
farm and are ready to be used in these tests. Just as soon as
these crops reach the proper grazing stage the shotes will be
turned into the fields and allowed to graze off the crops. A lot
of eight shotes will be used for dry lot feeding purposes.
(This project replaces former Hatch Project No. 9.)

KIDNEY WORM OF SWINE
(State Project No. 92)
Work on the life history of the swine kidney worm has been
continued along the same lines as previously reported. Eggs of
the kidney worm occur in urine of infested animals. Urine con-
taining eggs may be collected in a receptacle by confining the
infested animal in an elevated pen having a sloping tin floor.
These eggs sink to the bottom of the receptacle after a few min-
utes and they may be obtained in large quantities by various
methods of separation. Eggs so obtained may be cultured in
shallow petri-dishes containing sterile sand and a small quantity
of animal charcoal. It was found that cultures of the eggs of the
swine kidney worm would hatch in the laboratory both in the
incubator and at room temperature. More rapid hatching of the
eggs was obtained by placing the culture in a moist chamber and
placing the moist chamber in the incubator. Hatching was also
found to be facilitated by keeping the cultures stirred to allow
aeration. By using the above methods, eggs have been observed
to hatch in less than 24 hours. In the hatching process the larvae
release themselves from the egg by actively moving around and
making thrust-like movements against the wall of the shell.
Infestation of experimental animals has been produced by ad-
ministering the larvae through the mouth and also through the
nostrils. Large numbers of larvae may be recovered from the
liver of experimentally infested animals. Infestation has not
been produced thus far by placing larvae on the intact skin.

Annual Report, 1929

"LEECHES" OF HORSES
(State Project No. 62)

Due to the fact that there are other diseases that are of greater
importance than "leeches" on which investigational work should
be conducted, we would recommend that this project be classified
as inactive until some of the problems pertaining to a few of the
other more important diseases have been studied.

PARALYSIS OF THE DOMESTIC FOWL
(State Project No. 119)

Some of the studies started in 1928 have been completed and
others are still in progress. Paralysis was not produced when the
intestinal contents and scrapings of the intestinal walls from a
paralyzed chicken were fed to healthy birds. The brain from
paralyzed birds did not produce paralysis when fed to healthy
birds. In studies made on a nearby poultry farm in which an
experiment was allowed to be conducted it was found that paraly-
sis was not transmitted from the hen through the egg to the off-
spring. Also paralysis seemed not to have any relationship with
coccidiosis, since the flock had a very severe outbreak of coccidio-
sis as chicks. Several birds from time to time during the year
have been injected with various tissues of paralyzed birds with
no cases of paralysis being produced by such injections.
An experiment is in progress in which the drinking water is
being treated with antiseptics such as are used universally on
poultry farms. These studies have not progressed to the point
where any conclusions can be reached regarding whether or nbt
there is any relationship between continuous use of antiseptics in
drinking water and paralysis. Another experiment is being con-
ducted in an effort to find the causative agent by feeding the dif-
ferent tissues to birds of a susceptible age in which an enteritis
has previously been artificially produced. No conclusions have
been reached in this work as it has not been in progress long
enough.
Post mortem examinations of all paralyzed birds that are sent
to the diagnostic laboratory and otherwise received are being
made and detailed records are kept of the findings. Question-
naires are being filled out where it is possible to get them on farms
on which the disease occurs. From time to time visits are made
to the infested flocks to study the conditions under which birds
are kept and to secure diseased birds for use in this experiment.

Florida Agricultiural Experiment Station

MANSON'S EYE WORM OF POULTRY (Oxyspirura mansoni)
(State Project No. 64)
The work conducted to date on Manson's eye worm has just
been published in Agricultural Experiment Station Bulletin 206,
by Dr. D. A. Sanders. Since future experiments in connection
with Manson's eye worm will depend to a great degree upon the
findings of the research work on the life history of the cockroach,
Pycnoscelus surinamensis, by the Department of Entomology
and since Dr. Sanders has been detailed to work on anaplasmosis,
we would recommend that this project be specified as inactive at
this time.
DIAGNOSTIC LABORATORY REPORT
In addition to conducting research work on the above projects,
the department has maintained a diagnostic laboratory, and
diseased specimens from the various classes of livestock have been
sent to the laboratory for diagnostic reports on same. These
specimens are received from practicing veterinarians, officials of
the State Live Stock Sanitary Board, and livestock owners them-
selves. During the year 1,217 diagnoses were made. Numerous
inquiries concerning diseases of livestock, including poultry, have
been received and information given on these cases.

Annual Report, 1929

CHEMISTRY

Vilmon Neweell, Director.
SIR: I submit the following report of the Department of Chem-
istry for the fiscal year ending June 30, 1929.
Respectfully,
R. W. RUPRECHT,
Chemist.
DIEBACK OF CITRUS
(Adams Project No. 21)
The work on this project follows the same general lines as
during the previous year. Analyses of leaves and stems from nor-
mal and dieback affected trees indicate the following:
An increase in all forms of nitrogen in the diseased leaves.
A decrease in iron content.
An increase in phosphoric acid.
A slight decrease in total and reducing sugars, dextrose and
soluble starch.
A lower carbohydrate-nitrogen ratio.
An increase of calcium in the young shoots.
The relationship of potassium, magnesium, and manganese has
not as yet been determined.
Due to lack of travel funds it was impossible to make analyses
on leaves and stems from other than our own groves. It may be
that the above differences will not hold in all cases. We expect
to be able to get more samples this coming year to check this point.
Chlorosis is frequently associated with dieback in citrus, hence
analyses were made of chlorotic and normal leaves. The chlorotic
leaves showed differences similar to the dieback leaves with the
exception of the carbohydrates. While carbohydrates were higher
in chlorotic leaves than in normal, they were lower than normal
in dieback leaves. Here again, lack of material does not warrant
stating the above as a fact but only as an indication. No dieback
developed in the dieback grove but considerable dieback developed
in the clean cultivated plot in the cover crop experiment. Analyses
of soil from dieback affected trees and normal trees showed no
marked differences.

Florida Agricultural Experiment Station

DETERMINATION OF THE EFFECT OF VARYING AMOUNTS
OF POTASH ON THE COMPOSITION AND YIELD
AND QUALITY OF THE CROP
(Hatch Project No. 22)

The experiments using varying amounts (3, 5 and 10 percent)
of potash on oranges and grapefruit were continued. A good crop
of both oranges and grapefruit was harvested and analyzed. So
far as chemical analysis goes no difference between the different
treatment is apparent. However the oranges on the 3% potash
plots were judged inferior in physical appearance by a packing
house manager.
In order to test the keeping quality of the fruit from the various
plots two boxes of grapefruit and two boxes of oranges from each
of the plots were placed in cold storage. Due to rather unfavor-
able cold storage conditions, the decay was very heavy in all cases
and no conclusions as to the keeping qualities could be drawn. It
is planned to repeat these tests in more suitable cold storage next
year.

DETERMINATION OF THE FERTILIZER REQUIREMENTS
OF SATSUMA ORANGES
(Hatch Project No. 36)

Due to lack of funds the Satsuma experiments at Round Lake
and Panama City had to be discontinued in January. Although
these experiments had been conducted for five and six years, re-
spectively, no conclusive results were obtained, due in part to the
frequent cold spells that killed back the trees, especially at Round
Lake. Growth measurements of the trees at Panama City indi-
cate that three applications of fertilizer per year give the largest
increase in tree growth even when the same amount of nitrogen is
applied in two applications. These applications also appeared to
lessen the cold injury as there was less defoliation on the plots
receiving three applications.
A new Satsuma experiment was begun at Marianna in the fall.
Answers to three general questions are being sought in the ex-
periment: First, are two or three applications of fertilizer neces-
sary ? Second, can the inorganic forms of nitrogen be substituted
for the organic forms? Third, can all the phosphoric acid and
potash be put on in one application and ammonia alone used at the
other application ? A total of 180 trees are being used.

Annual Report, 1929

DETERMINATION OF THE EFFECT OF VARIOUS POTASH
CARRIERS ON GROWTH, YIELD AND COMPOSITION
OF CROPS
(Hatch Project No. 37)

These experiments comparing the muriate, sulfate and low
grade sulfate of potash on citrus were continued as outlined in
previous annual reports. Crops of fruit were harvested from the
Indian River grove and analyzed. As in previous years, no
marked differences due to the sources of potash could be detected.
The grove at Lake Alfred made a normal growth. As stated in
last year's report, we believe that in the Indian River section the
muriate of potash can safely be substituted for the more expen-
sive sulfate.
Due to lack of funds no truck crop experiments were conducted.

STUDY OF FERTILIZER REQUIREMENTS OF CITRUS
TREES WHEN GROWN ON MUCK SOIL
(State Project No. 66)

The citrus experiment on the muck soils west of Davie continues
to meet with misfortune. The flood last fall killed a large number
of the trees so that this summer the experiment was re-located
on another block of trees.

EFFECT OF VARIOUS FERTILIZER FORMULAS
(State Project No. 94)

The experiment with citrus at Lake Harris comparing low
phosphate fertilizers with normal phosphate fertilizers was con-
tinued. No differences in growth or appearances of the trees is
noticeable as yet.
The experiment with potatoes at Hastings comparing organic
with inorganic sources of nitrogen showed no striking differences
between the two sources. Sulfate of ammonia, when used as the
only source of nitrogen, did not produce as large a crop as the
other inorganic materials, nitrate of soda and leunasalpeter. Cut-
ting down the phosphoric acid to 4% in the fertilizer had no effect
on the yield. Top-dressing with nitrate of soda did not increase
the yield.
The experiments with tomatoes were discontinued, due to lack
of funds.

Florida Agricultural Experiment Station

CONCENTRATED FERTILIZER STUDIES
(State Project No. 95)
The concentrated fertilizer experiment at Lake Alfred con-
ducted in cooperation with the United States Department of
Agriculture was continued. No differences as yet can be detected.
All of the trees made a good growth and are in excellent condition.
In the Lake Harris experiment the trees receiving urea and
leunasalpeter are in just as good condition as those receiving the
ordinary sources of nitrogen.
In the potato experiment at Hastings the concentrated fertilizer
known as Nitrophoska No. 1, analyzing 15-30-15, did not give as
good results as the usual fertilizers. The concentrated fertilizer
seemed to delay germination. The injury is apparently due to
the ammonium phosphate content as similar results were observed
where ammonium-phosphate was used, and no injurious results
were apparent where a concentrated fertilizer low in phosphorus
was used.
The experiments with tomatoes at Bradenton were discontin-
ued, due to lack of funds.

DETERMINATION OF THE EFFECT OF GREEN MANURES
ON THE COMPOSITION OF THE SOIL
(Adams Project No. 96)
Further studies of the soils to which summer legumes-Crota-
laria, velvet beans, cowpeas and beggarweed-have been incor-
porated have demonstrated that under our climatic conditions it
is practically impossible to build up or increase the organic matter
content of the soil through the use of summer cover crops alone.
The periodic determination of the nitrate content of the soils
from the plats receiving the above mentioned summer legumes as
green manure has been followed for the past two years. It appears
from the results of these determinations that the utilization of
the nitrates formed from-the various summer legumes when incor-
porated with the soil is dependent upon the rainfall or the supply
of moisture in the soil. During the past two seasons very small
increases in the yields of corn and sweet potatoes have been ob-
tained by the Agronomy Department on these plats. These low
yields appear to be associated with the lack of water during the
season of 1926-1927, which was very dry throughout the period
of maximum formation of nitrates, and, consequently, a poor utili-
zation of the nitrates resulted. During the season of 1927-1928

Annual Report, 1929

there were excessive rains and there were only insignificant accu-
mulations of nitrates.
Certain winter legumes have been found to grow following some
of these summer legumes while they will not grow on the un-
treated soil. Vetch and Austrian peas are two such winter le-
gumes. During the current season the effect of the incorporation
of these winter legumes with the soil is being followed by periodic
studies of the nitrate content of the soils in which they have been
turned under.
Lysimeter Studies. The large lysimeters are being used in a
study of the effectiveness of summer legumes in building up the
organic content of deep sandy soils, and a study of the leaching
of plant nutrients during that process. Essentially the rotation of
the Agronomy Department, which consists of a summer legume
followed by a cash crop, is being used. Corn is being used as a
cash crop. The second year of this experiment has just closed,
but the analytical work for the year is not complete. The value
of cover crops in cutting down the percentage of leaching during
the rainy season is emphasized as the results show that where
nothing was growing, over 40% of the water falling on the tanks
as rain was lost, while where a good crop of Crotalaria was grow-
ing only about 27% of the water falling on the tanks was leached.
Following the turning under of the green manure crop there was
a large leaching of nutrients from the tanks which had Crotalaria
or some other manuring crop turned under. The percentages of
nitrogen leached, on a basis of the total amounts of nitrogen added
as green manure and as fertilizer, was smaller for the green ma-
nure tanks. The experiment is being continued.
Small Tanks. A series of small leaching tanks is being used
in order to study the most economical method of handling the
cover crop grown in the summer during the rainy season. Cro-
talaria and velvet beans handled in different ways are being used.
Half the tanks are planted with small citrus trees and the other
half are without trees. The use of the cover crop as a mulch
appears to give a better utilization of the nitrogen of the cover
crop and a conservation of the water so necessary to the utiliza-
tion of the nitrogen. The Crotalaria mulch has not proved as
effective as the velvet bean mulch. These experiments are being
repeated in other tanks and enlarged to include Natal grass, which
is an important non-leguminous crop in the citrus belt of the state.
The results obtained from these experiments are being used as a
basis of several field trials at the Citrus Experiment Station and
among some growers. It is believed that these experiments will

Florida Agricultural Experiment Station

give us some idea of the water requirements of the citrus tree.
The experiments will be continued and repeated until the indica-
tions of these earlier experiments are confirmed or refuted. They
will also be tried under grove conditions.
Laboratory studies have been carried out on the decomposition
of the Crotalaria plant and its parts.

EFFECT OF VARIOUS FERTILIZER TREATMENTS AND OF
SOIL AMENDMENTS ON TOMATOES
(Hatch Project No. 112)
Due to curtailment of our funds, we were unable to cooperate
as fully as heretofore with the United States Department of Agri-
culture in carrying out the work on this project. Experiments
with different concentrated fertilizers on tomatoes showed no dif-
ference between the concentrated materials and commercial fer-
tilizer.
The effect of manganese salts was studied on 13 different crops
as follows: Two experiments with tomatoes, seven with Irish
potatoes, one each with corn, lettuce, strawberries, cucumbers,
pole beans, beets and peppers, seven with bush beans, two with
carrots, two with cabbage and two with cauliflower. Manganese
salts gave increased growth and yields in all cases when used on
marl soils. In many cases the crops without manganese were a
total failure.
COMPOSITION OF CROPS AS INFLUENCED BY FERTILIZA-
TION AND SOIL TYPES-PECANS
(State Project No. 67)
The pecan fertilizer experiments were continued as outlined in
previous years. A crop of nuts was harvested from most of the
experiments and samples are being analyzed to determine what
changes the different fertilizers produced in the composition of
the nuts.
Results to date indicate that nitrogen and potash have the
greatest influence in growth of the pecan tree. The source of
nitrogen does not appear to influence the growth, both mineral
and organic sources giving about the same results.
DETERMINATION OF THE MINERAL CONSTITUENTS OF
VARIOUS FLORIDA-GROWN CATTLE FEEDS, AS COM-
PARED WITH FEEDS GROWN FARTHER NORTH
(Hatch Project No. 38)
This project has been inactive for the past year.

Annual Report, 1929

COTTON INVESTIGATIONS

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Cotton
Investigations for the fiscal year ending June 30, 1929.
Respectfully,
A. F. CAMP,
In Charge of Department.

COTTON BREEDING
(State Project No. 57)
During the season of 1928, cotton variety tests were conducted
at Gainesville and in eight different localities in West Florida.
Tests were run on two different soil types in three of the localities.
In each locality six or seven varieties were placed in a test de-
signed to give conclusive results; and a single-row test (with a
check every third row) of nine to fourteen varieties was planted
adjoining. Twenty-nine varieties were tested. The varieties
Willis, Lightning Express, Bottom's Prolific, Miller, Cleveland 54,
Coker Cleveland 884, Acala 31, and Rowden 40, were most pro-
ductive.
A breeding plot of the variety Council-Toole was planted near
Monticello, and a plot of hybrid stock (Council-Toole and Light-
ning Express) on wilt infected soil near Sneeds. Breeding stocks
of the above and also breeding stocks of Lightning Express and
second year hybrids of Lightning Express with Cook were planted
at Gainesville.
During the present season (1929), cotton variety tests are being
conducted at Gainesville, Monticello, Blountstown, Campbellton,
and Laurel Hill.
Breeding work to produce better adapted strains of cotton for
Florida is being continued, using the pure varieties and hybrid
stocks mentioned above. Selection work is also being started this
year on the varieties Willis and Miller.

Florida Agricultural Experiment Station

BOLL WEEVIL INVESTIGATIONS
(State Project No. 75)
Control. Additional information relative to the cost and ef-
fectiveness of early season poisoning was obtained from a study
of 60 individual tests scattered throughout the cotton-growing
area of the state and 52 one-eighth acre plots located at Gaines-
ville. The conclusions reached have been prepared for publica-
tion elsewhere. The following recommendations for the most
effective and economical method of poisoning, however, are of-
fered: Begin poisoning with syrup mixtures or powdered calcium
arsenate as soon as the cotton first squares, continuing at weekly
intervals for about four weeks, by which time practically all of
the weevils emerging from hibernation have found their way to
the cotton fields. Continue poisoning with calcium arsenate dust
until the crop is set if the weevils continue to be plentiful. Cal-
cium arsenate may be diluted with hydrated lime, making a 50-50
mixture, for use in the dusting machines. For use in mopping
with syrup mixtures calcium arsenate should not be diluted with
hydrated lime, since such a mixture cakes on the plants and
becomes ineffective.
Hibernation Studies. For the fourth successive season the
actual time of arrival of hibernated weevils in the fields was de-
termined by periodic examinations of cotton plants in plots ex-
posed to infestation. Again the period of heavy emergence ex-
tended from late in May through June, indicating that early sea-
son poisoning should start with the formation of squares and
continue through the month of June. Hibernation studies con-
ducted with 55,000 weevils placed in low temperature incubators
were continued, a large percentage of the weevils being satisfac-
torily held through the winter. By June 30, as high as 20 percent
of several groups of 1,000 weevils each, placed in the incubators
during October and November, were alive. Weevils can conse-
quently be carried through the winter for experimental work to
be conducted during the following spring.
Biology. A new apparatus for determining the thermotropic
reaction of insects was devised. The boll weevil showed definite
orientation in response to 260 F. at the chilled and 130 F. at the
heated end of the apparatus, respectively. The geotropic reaction
of the boll weevil was also studied, using both especially con-
structed cages in the field and inclined planes in the laboratory.
Studies on the resumption of egg-laying by the hibernated weevil
indicated that fertile eggs could be laid without a preliminary

Annual Report, 1929

five-day square diet. Longevity records indicated that the indi-
vidual weevil could live 257 days without food during hibernation;
143 days after emerging from hibernation; and a total of over
372 days. This is, respectively 17, 13 and 37 days longer than the
previously cited records for Anthonomus grandis Boh.
The mechanism of grub feeding was studied, the results indi-
cating that the grub does not escape from the cotton square be-
cause the different degree of hardness between the fruit shell and
the inner material of the square mechanically prevents the grub
from boring out. The grub pupates in the square, the pupa later
changing to an adult weevil, which emerges. The duration of the
fertility of the weevil after copulation was also determined. An
isolated weevil laid eggs as many as 201 days, nearly seven
months, after copulation. The females are consequently able to
lay fertile eggs on emerging from hibernation.

COTTON RUST
(State Project No. 76)
During the past year the work on cotton rust has been limited
to observations of field plots treated with potash. From these
observations it appears that lack of potash is but one of a number
of factors predisposing cotton to rust, since rust appeared to some
extent in well fertilized plots-the fertilizer containing potash in
addition to nitrogen and phosphorus.
In conjunction with Project No. 79, it was planned to analyze
cotton in different stages and conditions of growth in the hope of
ascertaining something as to the nature of the changes brought
about by the rust disease. The analyses of cotton plants from
last year were of a preliminary nature, and all plots had to be
abandoned this year when Dr. Walker, in charge of this work,
was called into Mediterranean fruit fly eradication work.

SEEDLING DISEASES OF COTTON
(State Project No. 77)
The only disease of this class that was worked on during the
past year was the F. moniliforme disease which attacks both
seedlings and bolls. The work included inoculation and physio-
logical studies with the causal parasite. Field observations ac-
companied by isolations have shown F. moniliforme to be of com-
mon occurrence on seedling cotton, but as yet it is not possible to
properly evaluate its damage. The same fungus, Fusarium moni-
liforme, causes a rotting of cotton bolls, which rot is perhaps only

Florida Agricultural Experiment Station

second in abundance to Diplodia rot in Florida. The field inocu-
lations have not been extensive, but sufficient to show the ability
of the parasite to cause boll rots through wounds or lesions on
the boll.
STUDIES ON COTTON WILT
(State Project No. 78)
Studies on the physiology of the wilt organism have been made.
The major portion of the time given to this project was devoted
to determining the effects of different amounts of potash on the
wilt disease. From two series of field plots from last year that
carried over into the present year and one series of plots planted
during the past spring, sufficient data are on hand to indicate that
potash, even in large quantities, does not markedly reduce the
incidence of wilt on the highly susceptible variety Trice.

COTTON PHYSIOLOGY-NUTRITION AND GROWTH
(State Project No. 79)
Work in the temperature tanks was continued during the past
winter, but results merely substantiated the material published
in Bulletin 189, Soil Temperature Studies with Cotton. Prelim-
inary analyses were made on material collected during the sum-
mer of 1928 as a beginning on a detailed study of the chemical
constitution of cotton plants at different stages of growth and
under different treatments of nitrates. The current year's plots
had to be abandoned on account of Dr. Walker being called into
Mediterranean fruit fly eradication work. As a consequence this
has not advanced beyond a preliminary stage.

Annual Report, 1929

ENTOMOLOGY
Wilmon Newell, Director.
SIR: I submit the following report of the Department of Ento-
mology for the fiscal year ending June 30, 1929.
Respectfully,
J. R. WATSON,
Entomologist.

LIFE HISTORY STUDIES AND CONTROL OF THE VELVET
BEAN CATERPILLAR
(Adams Project No. 7)
A new development in this project during the year was the
appearance of the velvet bean caterpillar in destructive numbers
on peanuts in the Everglades. Life history work had shown that
they could complete their development on peanuts but never be-
fore had the moths been observed laying eggs on peanuts in the
field. Evidently the absence of other host plants in the Ever-
glades forced the moths to do this. Damage to peanut plantings
was extensive and control measures were complicated by the fact
that arsenicals are extremely injurious to Everglade soils. Cal-
cium fluosilicate was therefore tried and found, on the whole, to
give satisfactory control. The general absence of birds in the
fields has contributed to the increase of this insect in the Ever-
glades and the planting of shrubbery has been recommended to
make the farms more attractive for birds.
This caterpillar was also very destructive to soybeans during
the summer. Early planting appears to be the only way of bring-
ing this crop through without severe damage from this pest.

FLORIDA FLOWER THRIPS
(Adams Project No. 8)
Control work on the Florida flower thrips (Frankliniella tritici
bispinosa) was undertaken in connection with the control of the
green citrus aphid, to investigate the possibility of controlling
both pests with one application of incesticide. The nicotine sul-
phate-lime dusts, which have been found to afford the most eco-

Florida Agricultural Experiment Station

nomical control of the green citrus aphid, are not very effective
in the control of the flower thrips. This is due to the fact that a
drifting cloud of dust which is effective in killing aphids does not
penetrate the bloom sufficiently to kill thrips.
Some attention was given to the source of infestation of these
thrips in citrus groves. It has also been necessary to make a
survey of the Thysanoptera of the state in order to render identi-
fication of this thrips more certain.
No serious infestations were noted on vegetable crops, includ-
ing tomatoes and strawberries, and no control measures were
undertaken on these crops.

ROOT-KNOT INVESTIGATIONS
(Adams Project No. 12)
In the chemical treatment of seedbeds, formalin was tried out
extensively. It was found that when applied in the dosage which
pathologists ordinarily use for the control of the fungous diseases,
very good control of root-knot is obtained. This chemical has,
then, the advantage that it will control nematodes as well as
fungous diseases, such as damp-off, in seedbeds; but it is more
costly than the treatment with sodium cyanide and ammonium
sulphate, especially when the fertilizer value of these chemicals
is taken into consideration. Further trials with calcium cyanide
as a possible substitute for sodium cyanide were made. These
trials indicated the superiority of the latter in many ways.
Along the lines of control by cultural means, tests were made
which indicate that Crotalaria, particularly C. spectabilis, can be
substituted for velvet beans in the summer clean-up of infested
fields. No cases of root-knot have been observed on Crotalaria
even when planted in heavily infested soil. On account of the
slow early growth of Crotalaria it would seem advisable in some
cases to plant alternate rows of Crotalaria and cowpeas, using the
Iron or preferably the Brabham variety. The Victory cowpea,
which was developed by the United States Department of Agri-
culture as a nematode-resistant variety, has been found to be quite
heavily infested under Florida conditions. It cannot be recom-
mended for control of nematodes here.

INTRODUCTION AND STUDY OF BENEFICIAL INSECTS
(Hatch Project No. 13)
For the past two years the chief activity under this project has
been the attempt to introduce from Cuba and establish a tachinid

Annual Report, 1929

parasite of the sugarcane borer. Thorough search of the fields
where this parasite was introduced last year has failed to estab-
lish its presence. These parasites were liberated in a cane patch
belonging to a private owner who unfortunately burned it over
during the winter. It therefore seemed advisable to plant a field
of cane on station grounds where such mishaps could be avoided.
An acre of low raw land at the Citrus Experiment Station was
cleared and planted. For some unknown reason the cane was not
as heavily infested by the borer as usual during the past year.
The infestations were so low that it did not seem an opportune
year for further introductions of the tachinid parasite. Hence
no attempts were made along this line.
A parasite of the greenhouse whitefly has been brought in and
an attempt is being made to determine the possibility of its at-
tacking the citrus whitefly.

LARGER PLANT BUGS ON CITRUS AND TRUCK CROPS
(Adams Project No. 14)
During the past year activities under this project have been
centered around the further investigation of the relation of Cro-
talaria as a cover crop in citrus groves to possible damage from
pumpkin bugs (Nezara viridula) to fruit in the fall. Pumpkin
bugs find the large succulent pods of Crotalaria very attractive
food. As long as there are green pods on the Crotalaria observa-
tions have shown that the pumpkin bug will not leave the Crota-
laria even for ripe fruit; but if the plant bugs become so numer-
ous as to cause all the pods to drop from the Crotalaria or if the
Crotalaria is cut down by frost or drought, there is danger of a
serious migration of plant bugs to citrus. Plant bugs do not feed
on the Crotalaria in large numbers until the pods begin to form.
It has been determined that a mixture of beggarweed and Crota-
laria is a dangerous combination in a citrus grove. Plant bugs
breed on the beggarweed all summer and after this dies down or
matures in the early fall the plant bugs migrate to the Crotalaria,
often in sufficient numbers to take the pods all off, in which case
there may be a second migration to citrus.
Many groves where Crotalaria is grown have very few plant
bugs, due to the abundance of parasites, particularly the tachinid
fly (Trichopoda pennipes). It has been found that one can pre-
dict the abundance of plant bugs a month in advance of the dan-
gerous period (November) bv observing the percentage of para-
sitized plant bugs in September and October.

Florida Agricultural Experiment Station

Further observations were made of the egg parasite, Telenom-
ous megacephalus Ashm. This parasite was not as common this
year as last.
STUDIES OF THE BEAN JASSID
(Adams Project No. 28)
The bean jassid (Empoasca fabae Harris) was not abundant in
the northern part of the state during the fall of 1928 and spring
of 1929 and no extensive control experiments were carried on. A
small patch of beans planted by the Entomology Department for
nemadote experiments was rather heavily infested with the jas-
sids and some control experiments were tried on these. Four
percent nicotine sulphate-lime dust freshly mixed and a pyre-
thrum dust made according to the formula of E. G. Price of Sher-
man, Texas, were used but neither gave good results, even when
used under a hood.
Two liquid sprays were used. (1) 40% nicotine sulphate, 1 to
400, plus soap at the rate of six pounds to 50 gallons, gave a 50%
kill. When used at the rate of 1 to 800 with six pounds of soap to
50 gallons, a very small percentage of the insects were killed. (2)
A pyrethrum compound, one ounce to four gallons of water, plus
soap at the rate of six pounds to 50 gallons, killed 100% of insects
hit by spray. When used at the rate of one ounce to eight gallons
with six pounds of soap to 50 gallons, 60% of insects were killed.
The results indicate that liquid sprays are more valuable in con-
trol of these jassids than are the dusts.

THE GREEN CITRUS APHID (Aphis spiraecola)
(Adams Project No. 60)
The life history studies were continued as during previous
years. Particular attention was paid to the weather conditions
which bring about infestation. It seemed that the critical factor
in the weather was the mean temperature during January.
When this is above 600 F., aphid outbreaks are apt to occur the
following spring. This, however, may be inhibited by a severe
freeze which cuts off their food supply, or by heavy dashing rains.
The predators were shown to be somewhat more efficient dur-
ing the spring of 1929 than was thought to be the case in previous
years. Although they cannot control an outbreak when weather
conditions are favorable for rapid multiplication. they do greatlv
delay the citrus anhis infestation, particularly during the cold
weather when aphids are not multiplying so rapidly. The study

Annual Report, 1929

of the seasonal history of these predators was continued. Some
of them are found only during the winter, others during the
warm part of the year.
Among control measures, the thorough clean-up of aphids on
young trees during the winter, particularly in January, combined
with the pushing of the spring growth by cultivation and fer-
tilization, was shown to be very efficacious in preventing an
outbreak.
One of the most important developments of the work was the
discovery and testing out of more efficient spreaders which en-
able very much smaller quantities of nicotine sulphate to be used.
Among these better spreaders was an oil derivative and various
oleates. The use of these spreaders will reduce the cost of the
aphicides by half, a very important saving as nicotine sprays are
always expensive.

CONTROL OF DECIDUOUS FRUIT AND NUT CROP INSECTS
(State Project No. 82)
This project has centered around the control of insects attack-
ing pecan trees and has been carried on at the Monticello Field
Laboratory.
Experiments for the control of the nut case-bearer with sum-
mer sprays showed absolutely no control. This was to be ex-
pected, since the larvae in entering the nut do not eat the outside
but merely pry it loose and discard it. In the laboratory, larvae
entering as many as two heavily sprayed nuts a day showed no
apparent injury from the arsenic and reached maturity except in
a few cases of parasitism. Some results were obtained in control
with a dormant spray but the percentage of kill is not high enough
to be of commercial benefit.
The shuckworm was scarce during the 1928 season, probably
due to the eggs being washed off of the nuts before hatching.
Parasitism was not so high as in 1927 and emergence was consid-
erably earlier in 1929 than in 1928, due probably to the mild
weather during the winter of 1928-29.
The percentage of parasitism on the leaf case-bearer was con-
siderably lower than in 1927-28. There were less dead from cold.
Predatory insects accounted for about 10% of the overwintering
hibernacula.
Mr. Walker, in charge of this work at Monticello, was called to
assist in the campaign against the Mediterranean fruit fly and
the work has been largely dropped until his return.

Florida Agricultural Experiment Station

The new laboratory building is about completed and will be
ready for occupancy shortly after July 1. It is located about two
miles south of Monticello.

LIFE HISTORY STUDIES OF PYCNOSCELUS SURINAMEN-
SIS L:, THE ROACH WHICH IS INTERMEDIATE HOST
OF MANSON'S EYEWORM
(State Project No. 108)
Further attempts were made to breed the roaches in cages in
order to secure data on their life history. Roaches were captured
under debris in the hay lots on the Station grounds and placed in
cages with various food materials. On August 20, 1928, 11
roaches (six adults and five partly grown nymphs) were captured.
Three adults were placed in a cage with water, bread, corn meal
and some droppings and soil from a poultry house. One remained
alive until October but no eggs were laid. The remaining roaches
were placed in a large cage in the insectary with water and food
as above. The last individual of this lot died November 1. One
egg capsule was deposited but eggs failed to hatch.
On September 10, six adults and one nymph were captured and
placed in a cage in the insectary. The last individual of this lot
died November 23. No reproduction took place. Later search
failed to reveal any roaches for further tests. The work will be
continued with special attention to cage conditions, kinds of
food, etc.

Annual Report, 1929

HOME ECONOMICS

Wilmnon Newell, Director.
SIR: I submit the following report of the Department of Home
Economics for the fiscal year ending June 30, 1929.
Respectfully,
OUIDA DAVIS ABBOTT,
Head of Department.

DETERMINATION AND IDENTIFICATION OF ORGANISMS
WHICH CAUSE THE SPOILAGE OF CANNED
VEGETABLES IN THE SOUTH
(Purnell Project No. 69)
Corn has been sterilized, using the following methods:
1. Intermittent sterilization, varying the time.
2. One period sterilization in water bath, varying the period
of time.
3. Steam pressure sterilization, varying the time and pressure.
It has been found that if the corn has been packed into the jars
tightly and little water has been added, 15 pounds pressure for
60 minutes did not protect the corn against spoilage.
Plate cultures have been made from the spoiled corn, and two
pure cultures have been obtained. One of these is an aerobic
type of bacillus which is non-gas forming. This organism has
caused a type of spoilage similar to flat sour when sterile canned
corn has been inoculated with it. The other organism isolated is
a gas former and apparently a facultative anaerobe. These two
organisms have as yet not been identified.

DETERMINATION OF WHETHER CHLOROPHYLL, CHLORO-
PHYLL ALPHA AND BETA, THE PETROLEUM ETHER
EXTRACTS OF THE YELLOW PIGMENTS OF AL-
FALFA, CAN BE USED AS A SOURCE OF
VITAMIN A IN ANIMAL NUTRITION
(Purnell Project No. 70)
In the preliminary work on this project using alfalfa seed, ger-
minated and ungerminated, etiolated and green 10-day old alfalfa

Florida Agricultural Experiment Station

seedlings as a source of vitamin A for rats on a vitamin A-deficient
diet, it has been found that:
1. Ungerminated alfalfa seed protect rats against xeroph-
thalmia.
2. Germinated alfalfa seed and green and etiolated 10-day old
alfalfa seedling cure rats of xerophthalmia.
3. All seedlings and seeds used promoted growth of the experi-
mental animals.
In the determination of whether chlorophyll and chlorophyll
derivatives promoted growth and cured xerophthalmia in albino
rats the data collected show that:
1. Crystalline chlorophyll did not cure xerophthalmia.
2. Methyl chlorophillide did not cure xerophthalmia.
3. Ethyl chlorophillide did not cure xerophthalmia.
4. Phaeophytin did not cure xerophthalfnia.
5. Ether extracts of alfalfa were slightly effective in delaying
death of the experimental animals.
Histological sections have been prepared from the tissues.
Papers are being prepared on these sections. Papers are also
being prepared on the effects of feeding the above plants and plant
extracts to experimental animals.

A STUDY OF SOME OF THE CONSTITUENTS OF CITRUS
FRUITS, LOQUATS, ROSELLE, AND GUAVA; PECTIN,
OILS, AND GLUCOSIDES
(Purnell Project No. 71)
Various methods of extraction of pectin from citrus fruits
have been studied. The method finally adopted as most satisfac-
tory is:
1. Extract the peel of the fruit with hot alcohol by means of a
Sohxlet extractor. (To permit extraction of large quantities of
peel, a five gallon extractor was designed based on the Sohxlet
principle.)
2. Dry the residue from the alcohol extraction in vacuo at 600 C.
3. Extract the dried pomace with .4% to .5% citric acid solution
at 900 C. for one hour.
The pectin obtained by alcohol precipitation with subsequent
drying was a slightly gray (almost white) powder, in most cases
having no taste of the citrus fruit from which it was derived.
The pectins obtained by the above described method are now
being examined as to pectic acid content, jell strength, degree of
methylation, etc., as outlined in the statement of the project.

Annual Report, 1929

The pectin (and pomace not yet extracted) represents the yield
of 8,000 kumquats, 3,000 grapefruit, 600 sweet oranges, and 500
loquats.

THE DETERMINATION OF THE NUTRITIONAL STATUS OF
RURAL SCHOOL CHILDREN IN FIVE REPRESENTA-
TIVE COUNTIES IN FLORIDA
(Purnell Project No. 72)
During the fiscal year 1928-29 this project has been completed.
Physical examinations and laboratory tests have been made on
3,380 children living in Alachua, Columbia, Hillsborough, Indian
River and Jackson counties. Diets for 2 or 3-day periods have
been obtained for 1,850 of these children.
The principal findings of the study are:
1. The following defects occur in more than 35% of the chil-
dren: hookworm, underweight, defective tonsils, anemia, and
defective teeth.
2. Rickets and goiter occur less frequently among native Flor-
ida children than among children from other sections.
3. Tonsil defects were found to occur much more frequently
than adenoids.
4. Weight is not a reliable standard to determine the nutritional
status of children, as shown below.
After a careful study of the data it was noted that other factors
in addition to the diet influenced weight. From the results ob-
tained in this survey it can be definitely stated that height-weight
ratios are not an index as to the health and general condition of
nutrition. The reasons for this statement are as follows: (1)
The study of the diets of 1,850 children fails to show that the grade
of diet influences weight. (2) The following physical defects
present in children of normal weight show that they are not in
the best health: hookworm, defective tonsils, enlarged thyroid.
It has been found that 71% of the overweight children had
hookworm and that 57% of the children with normal weight were
hookworm subjects. These two facts point out very clearly that
height-weight ratios cannot be used as an index of health of chil-
dren in areas where hookworm is prevalent; and that diet is not
the only factor which influences weight. It has also been found
that 58% of the children with defective tonsils are underweight.
The percentage of underweight children free from defective ton-
sils is 13%. These data show that defects of tonsils have an influ-
ence on height-weight ratios. Another factor which influences

Florida Agricultural Experiment Station

weight is the condition of the thyroid gland. The data show that
of the 77 children with an enlarged thyroid 56, or 73%, were un-
derweight. It must be recognized that this defect occurs in a
small percentage of cases and will not affect the average weight
of a large group. However, in judging the condition of a child's
health by his diet, it must be remembered that this factor plays
an important part.
On the basis of the effect of various factors other than diet,
height-weight ratios are not an index as to diet. Thus in order to
study the effects of diet on height and weight these other factors
must be eliminated.
The various types of food in the diet of the children were given
numerical values, and on this basis the diets were scored. The
data show that 23% of the underweight children had a diet lacking
in four of the essential food constituents, a score of 15-35, while
23% of the overweight children had the same diet, and 32% of the
children with normal weight had a diet of the same score. Of the
total children, the percentage with a good diet (having a score of
75-95) show very little variation for underweight, overweight, or
normal weight; the values being 3.9%, 4.4% and 4.1%, respectively.
In each group there were children who had a perfect diet, 1.2%
of the underweight as compared to 1.7% for overweight and 1%
for children with normal weight. The data show definitely that
for each group the scores of children vary little, and also that the
grade of diet does not influence weight for this group of children.

THE RELATION OF GROWTH TO PHOSPHORUS, CALCIUM
AND LIPIN METABOLISM AS INFLUENCED BY
THE THYMUS
(Purnell Project No. 142)
This project was approved by the Office of Experiment Stations
on May 9, 1929. Work will be started on July 1, 1929.

Annual Report, 1929

HORTICULTURE

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Hor-
ticulture for the fiscal year ending June 30, 1929.
Respectfully,
A. F. CAMP,
Horticulturist.

TESTING OF NATIVE AND INTRODUCED SHRUBS AND
ORNAMENTALS AND METHODS OF THEIR
PROPAGATION
(Hatch Project No. 52)
Approximately 50 new species were added to past acquisitions,
these including both shrubs and trees. Propagation tests have
been run on all of the introduced materials, this giving informa-
tion as to best method for local conditions.
Extensive experiments have been conducted with various
chemicals which might stimulate or hasten the rooting of cuttings.

VARIETY, PROPAGATION, AND PLANTING TESTS OF
PEAR, AVOCADO, JAPANESE PERSIMMON, FIG,
AND OTHER FRUITS
(Hatch Project No. 58)
All varieties of these fruits previously reported are now attain-
ing bearing age. Due to proximity to Mediterranean fruit fly
infestation, all fruits were removed prior to maturity this season.
The jujube (Ziziphus jujuba) has proven iself adapted, two
varieties having attained fruiting size. Ziziphus mauritiana can-
not withstand low temperatures, the trees being severely killed
back by 250 F.

VARIETY TESTS OF BERRIES (Rubus spp.)
(Hatch Project No. 59)
Of the numerous varieties under test, previously reported, one
obtained from California under the name "Advance" has proven
best adapted and worthy of distribution. This variety is a vig-
orous grower, early in maturity, prolific bearer, and apparently

Florida Agricultural Experiment Station

immune to the double-blossom disease. The berries are quite
firm, making for good canners or shippers.
Seedlings of the Marvel blackberry, from seeds taken at ran-
dom from double-blossom affected and free plants, almost univer-
sally developed the disease. Some breaking up was noted but no
character of apparent value was detected.
An unknown variety obtained from Oregon has made a thrifty
growth and produced fruit of a good quality, although it is quite
late in maturity.

VARIETY TESTS OF GRAPES
(Hatch Project No. 49)
Variety tests of grapes have been continued. Of those pre-
viously reported the varieties Champanel, Lukfata, Extra, Herbe-
mont, Jacquez, Jaeger 43, and Muench seem to be the best adapted,
they continuing to be vigorous and produce large yields. The
quality of most of these is generally inferior to the desired table
variety.

OBSERVATION AND TESTING OF VARIOUS CITRUS
HYBRIDS
(Hatch Project No. 51)
Numerous hybrids have been utilized as possible rootstocks for
Satsumas. Those showing the most merit at present are the
citranges (Morton and Rusk) and citrangequat. Seedlings of
the above show no apparent variation from the parent tree. All
are vigorous in growth, quite cold resistant, and apparently form
congenial union with the Satsuma.

TESTS OF DIFFERENT STOCKS AS ROOTSTOCKS FOR
SATSUMA ORANGES
(Hatch Project No. 81)
Two hundred additional trees were added to former plantings.
These were of Owari and Wase varieties on sour orange, Poncirus
trifoliata, Rusk and Morton citranges, and citrangequat rootstock.
None has as yet reached an age where appreciable differences in
behavior of the cion can be noted.

FUNDAMENTAL PHYSIOLOGY OF FRUIT PRODUCTION
(State Project No. 111)
On account of the interruption of this work caused by the
absence of its leader on Mediterranean fruit fly eradication work,
no report of progress is available at this time.

Annual Report, 1929

PROPAGATING, PLANTING, AND FERTILIZING TESTS
WITH TUNG-OIL TREES
(Hatch Project No. 50)
Yields for the year on test plots were smaller than the antici-
pated increase, this probably being due to heavy rainfall of the
summer leaching nitrogen. Averages for the 10 oldest trees show
an annual yield, in shelled seeds, of 21 pounds per tree from the
ninth to the fourteenth years. Complete fertilizers seem to be
required to secure maximum growth and fruiting.
Seed selection is now generally practiced for nursery stock, the
"multiple-fruiting" type apparently being the most desirable
from the standpoint of seed production.

FIELD STUDIES OF THE DISEASES AFFECTING THE
PECAN, INCLUDING CONTROL MEASURES
(State Project No. 44)
This work is being conducted in cooperation with the Depart-
ment of Plant Pathology and a progress report will be found under
Project No. 4 of that Department.

FIELD STUDIES OF THE INSECTS ATTACKING THE PECAN,
INCLUDING CONTROL MEASURES
(State Project No. 45)
This work is being conducted in cooperation with the Depart-
ment of Entomology and a progress report will be found under
Project No. 82 of that Department.

VARIETY RESPONSE OF PECANS TO DIFFERENT SOIL
TYPES, LOCALITIES, ETC.
(State Project No. 46)
Observations have been made on several varieties that have not
been noted previously. The Elliott, growing in the orchard of
Lee Mathis, Paxton, Florida, and introduced from Milton, Florida,
about 1912 or 1913, makes a thrifty, productive tree of moderate
size when grown on soils such as are to be found in the northern
part of Walton County. The nut is rather small, roundish, some-
what pointed, with moderately distinct markings, cracks fairly
well, and has a good flavored kernel. The Mahan, previously re-
ported, is being checked in different parts of the pecan belt.
Cover crops are being more generally used over the pecan belt.
This practice is proving profitable to pecan growers. Work under
the project is being continued.

Florida Agricultural Experiment Station

COOPERATIVE FERTILIZER TESTS IN PECAN ORCHARDS
(State Project No. 47)
This work was continued in full through the year 1928-29.
Generally, trees in the fertilized plots are making better growth,
and better production of nuts, than those in unfertilized plots.
The Department of Chemistry is making a study of the chem-
ical analyses of a sample of nuts produced in each plot in all fer-
tilizer experiments.

VARIETY AND STOCK TESTS OF PECAN AND WALNUT
TREES
(State Project No. 48)
The varieties of pecans and walnuts in the variety orchard are
the same as given in the report for 1928. Several pecan trees of
different varieties matured nuts in the fall of 1928.
A cover crop of Crotalaria striata and C. spectabilis mixed,
amounting to 23,500 pounds of green material per acre, was
turned into the soil in 1928. In the spring of 1929 a cover crop
of Austrian winter peas, amounting to 8,300 pounds of green
material per acre, was turned into the soil.
Many of the trees are making excellent growth, and should
begin to bear nuts rather generally during the next few years.

REJUVENATION EXPERIMENTS WITH PECAN TREES
(State Project)
The trees in the rejuvenation experiment are making fair to
excellent growth. Many of them are beginning to produce nuts
in small quantities.

COOPERATIVE COVER CROP TESTS IN PECAN ORCHARDS
(State Project No. 80)
Pecan trees growing in plots where cover crops are being grown
are in much better condition than where no cover crop is grown.
It is impossible at the present time to state which is the best cover
crop for pecan orchards. However, Austrian winter peas and
hairy vetch are the most promising legumes for winter cover
crops, and Crotalaria spectabilis for summer growth.

PHENOLOGICAL STUDIES ON TRUCK CROPS IN FLORIDA
(State Project No. 110)
The "time of planting" tests with Irish potatoes extended over
a wider range of time than in the previous two years. Beginning

Annual Report, 1929

December 15, fortnightly plantings were made at Hastings until
January 26, and then weekly until February 16. Planting dates
and yields were as follows:
Planting Date Yield bbls. per acre
No. Is No. 2s
No. 1 ................ Dec. 15, 1928 33.53 15.63
No. 2 ................ Dec. 29, 1928 21.47 18.65
No. 3 ................ Jan. 12, 1929 40.10 17.97
No. 4 ................ Jan. 26, 1929 39.10 19.68
No. 5 (check) ......... Feb. 2, 1929 25.13 25.58
No. 6 ................ Feb. 9, 1929 17.28 17.99
No. 7 ................ Feb. 16, 1929 3.98 15.74

On August 31 five separate lots of Red Bliss potatoes were
planted at La Crosse. These lots were as indicated below, with
yields in barrels of prime potatoes shown for each lot:
Lot Yield
Bbls. Prime
1. Freshly dug Long Island, treated chlorohydrin ....... 15.36
2. Freshly dug Long Island, treated chlorohydrin ........ 17.09
3. Freshly dug Long Island, not treated (check).......... 7.36
4. Spring dug Everglades, not treated .................. 9.68
5. Spring dug New Brunswick, Canada (cold storage).... 20.99

Fall experiments with excelsior mulch on Irish potatoes indi-
cated an increased yield, through its use, of nearly 60%. High
temperature is depressing to growth and the excelsior mulch de-
creased soil temperatures early in the fall from 8 to 15 F.
Special hill selections made in 1927 and multiplied in Maine
were grown in Florida for the second season in 1928. These
showed a wide variation in production, mainly due to differences
in Mosaic and leaf-roll. However, even among units where no
disease was evident there was a distinct indication of the superi-
ority of certain selections.
Potato seed of the Bliss variety has a marked tendency to pro-
duce multiple stems per seedpiece, especially if the seedpieces are
large. A test was made in the spring of 1929 to determine
whether any marked increase in prime tubers would result if all
of the sprouts were pulled except one per hill. Out of a total of
254 hills not suckered as compared to 235 hills that were suckered,
the average weight of primes per hill was 363 gr. and 375 gr.,
respectively. This indicates that it would not pay to sucker.
A planting of horseradish made in December, 1928, has made a
satisfactory growth.

Florida Agricultural Experiment Station

PLANT PATHOLOGY

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Plant
Pathology for the fiscal year ending June 30, 1929.
Respectfully,
W. B. TISDALE,
Plant Pathologist.

Cooperative investigations conducted during the year were with
the Florida State Plant Board on citrus canker and in the identi-
fication and handling of all inquiries and specimens sent to them
involving plant diseases, also with the Bureau of Plant Industry
of the United States Department of Agriculture on tomato dis-
eases.
A field laboratory has been erected and equipped at Monticello
to further facilitate investigations of pecan diseases. Corre-
spondence and identification of plants, diseases and fungi was
somewhat more than for last year. About 500 specimens were
added to the cryptogamic herbarium and approximately 2,000
specimens to the phanerogamic herbarium.
The following publications have been made by members of the
department during the year:
Coconut Bud Rot in Florida. By J. L. Seal, Fla. Exp. Sta. Tech.
Bul. No. 199: 1-87, 1928.
Variety Tests of White Potatoes. By L. O. Gratz, Fla. Exp. Sta.
Bul. No. 201: 302-314, 1928.
Mottle Leaf, Marl Chlorosis, Nitrogen Starvation, Three Forms
of Chlorosis on Citrus Trees. By A. S. Rhoads, Citrus Indus-
try, 9: 3-5, 28-29, Dec., 1928.
Seed Potato Treatments for Rhizoctonia Conducted in Northeast-
ern Maine from 1925-1928. By E. S. Schultz, L. 0. Gratz and
Reiner Bonde, Proc. Pot. Assoc. of Am., 15: 102-112, 1928.
Yields of Northern Certified Seed Potatoes in Florida. By L. 0.
Gratz, Proc. Pot. Assoc. of Am., 15: 164-169, 1928.
Stemphylium Leaf Spot of Tomatoes. By Geo. F. Weber, (Abst.)
Phytopathology 19:92, 1929.

Annual Report, 1929

A Disease of Tobacco Seedlings Caused by Septomyxa affinis
(Sherb) wr. By W. B. Tisdale, (Abst.) Phytopathology 19:90,
1929.
Pathogenicity of Multisporidial and Monosporidial Cultures of
Ustilago zeae (Beck) Ung. By A. H. Eddins, (Abst.) Phyto-
pathology 19:91, 1929.
Progress in the Control of Black Shank of Tobacco Through Dis-
ease Resistance. By W. B. Tisdale, (Abst.) Phytopathology
19:93, 1929.
The Damping Off Disease of Boston Ferns. By Erdman West.
Fla. Exp. Sta. Press Bul. 410, 1929.
Ammoniacal Copper Carbonate and Other Stainless Fungicides.
By Erdman West. Fla. Exp. Sta. Press Bul. 411, 1929.
Bordeaux Paste Treatment for Stem-end Decay of Watermelons.
By Geo. F. Weber, Fla. Exp. Sta. Press Bul. 412, 1929.
Equipment for Spraying and Dusting Pecan Trees. By R. E.
Nolen, Fla. Exp. Sta. Press Bul. 413, 1929.
Pecan Scab Control. By R. E. Nolen, Fla. Exp. Sta. Press Bul.
414, 1929.
Water Injury to Citrus Trees. By A. S. Rhoads, Am. Fruit Grow-
ers 49: 8, (Apr.) 1929.
The Occurrence of Tuckahoes and Poria cocos in Florida. By
Geo. F. Weber, Mycologia 21:113-130, 1929.
Strawberries in Florida: Culture, Diseases and Insects. By A.
N. Brooks, J. R. Watson and Harold Mowry. Fla. Exp. Sta.
Bul. 204: 477-524, 1929.
Following are summarized reports of the various investiga-
tions, conducted by the Departmental staff, by projects.

CITRUS STUDIES
GUMMING OF CITRUS
(Adams Project No. 1)
Psorosis and Gummosis. Preliminary work on this project was
begun in the spring of 1927. In the vicinity of Cocoa 358 trees
are being treated in portions of five groves, and 14 additional trees
observed to be attacked by either psorisis or gummosis were
treated for the first time, thus making a total of 372 trees in-
spected this year. The treatment consisted of removing the loose
scaling bark and in lightly scraping off the dark outer portion of
the bark, not only coincident with the lesion but also well in
advance of it, and, in the case of the trees treated this year, paint-

Florida Agricultural Experiment Station

ing with lime-sulphur wash (1/2 lb. dry lime-sulphur to 1 gal.
water).
Many of the trees treated exhibited no further development of
these diseases at the places treated but frequently exhibited new
infections that had developed at other points on the trunk or
branches. In others, especially tangerine trees with long-stand-
ing cases of psorosis or gummosis, the disease was checked insofar
as the trunk or main limbs were scraped but the scraping did not
prove to have been carried on sufficiently far in advance of the
lesions to completely arrest the progress of the disease. Fully
half of the tangerine trees treated had long-standing cases of
psorosis involving much of the trunks and lower portions of the
main limbs, with the disease slowly but surely killing the bark.
At the last treatment administered only a few marginal areas or
upper limits of lesions on main limbs, together with some new
lesions on bark that had not been scraped previously, required
treating, the disease apparently being cured in the scraped places,
as evidenced by the sloughing off of the exfoliated portion of the
scraped bark and the regaining of the normal appearance by the
underlying regenerated bark in many cases.
The bark scraping method of treatment is believed to be a par-
ticularly promising method for the control of both psorosis and
gummosis, provided it is administered before the life of the tree
or part of the tree attacked becomes seriously threatened by the
inroads of the disease. When carefully administered, the treat-
ment is safe and a vastly more efficient and reliable method of
curing psorosis and gummosis than the old method previously
used in which merely the loose, scaling bark and gum masses were
scraped off and the areas painted with carbolineum, which fre-
quently proved highly injurious and rarely ever checked the dis-
ease unless the treated tree or branch was killed.
Scaly Bark. Work has been along two lines: (1) an attempt
to isolate the organism in the grove and, (2) an attempt to demon-
strate the organism in the tissue.
The first type of work was begun last spring in the Indianola
Hotel property. Sterilized spots were enclosed in built up minia-
ture Swiss chambers and visited one and two months after. Only
50 such were set up. Anthracnose and melanose fungi were the
only organisms obtained.
Young material carefully killed and carefully run through alco-
hols and xylol and embedded was sectioned and stained in many
ways. No organism was demonstrated.

Annual Report, 1929

MELANOSE AND STEM-END ROT OF CITRUS
(Adams Project No. 3)

The experimental work on this project was very similar to that
reported last year. The grove experiments were repeated. The
experiment consists in the comparison of various commercial oil
emulsions with Bordeaux mixture. Bordeaux-oil showed less
melanose than oil only, used in Block 4.
Block Application % Grade 1 % Grade 2 % Melanose % Shadowing
1 Bordeaux
+Oil A ...... 69 31 24 2
2 + Oil B ...... 56 44 32 6
3 + Oil C ...... 54 46 26 /
4 Oil B Only.... 45 55 42 1
Oil "A" produced the greatest amount of first grade fruit and
showed least melanose infection. The investigation of control
methods, under this project, will be stressed during the coming
year.
CITRUS CANKER
(Adams Project No. 11)

Investigations of citrus canker, caused by Phytomonas citri
(Hasse) S. A. B., have been carried on during the past year along
the same lines as reported for the year before. The following
experiments have been completed with sufficient data to warrant
the following summaries:
A. THE ACTIVITIES of P. citri when grown in potato broth
at various temperatures were observed, as follows:
1. Rate of growth was tested by observing the change in popu-
lation as shown by direct microscopic count at frequent intervals.
It was found that at 11.50 C. there was a decided lag period in
the growth. The rate increased with rise in temperature until
28' C. to 31' C. gave optimum. At 280 C. the organism died out
at the end of 40 days, probably from lack of food.
2. Changes in starch content of the cultures were tested by
the iodine-starch method and it was found that starch was hydro-
lized most rapidly at 28 C. The rate decreased as the tempera-
ture rose or fell from that point.
3. The change in hydrogen-ion concentration was tested by the
electrometric method and there was found to be no correlation
between temperatures and change in pH.
B. THE LONGEVITY of P. citri in sterilized and unsterilized
sandy and muck soils and sandy and muck soil concoctions was

Florida Agricultural Experiment Station

tested. Proof of viability of the organisms was made by inocu-
lating grapefruit plants with suspensions from the test soils.
It was found that in sandy soils and sandy soil concoctions
which were not sterilized, P. citri died out in one to five days.
However, if the same soil preparations were sterilized, P. citri
lived for 150 days, but not for 200 days.
In muck soils and muck soil concoctions which were sterilized
P. citri died out in 2 to 13 days. However, if the same muck soil
preparation were sterilized P. citri lived for at least 150 days.
Tests are being made to determine if these same organisms will
live for 200 days.
CITRUS SCAB
(Hatch Project No. 24)
This project has been inactive for some time during the past.
It is deemed advisable, at this time, to renew investigations on the
project, especially pertaining to control of this disease in the field.
The spray schedule for citrus trees has stood for a number of
years without careful following with investigational work and
this it is proposed to undertake.
THE DISEASES OF THE CITRUS APHID
(State Project No. 114)
From the general knowledge and facts thus far observed there
is all evidence of an outward or expanding period of aphid devel-
opment with the increase of citrus growth. During this expan-
sion period there is little chance for epidemic conditions of the
disease caused by Empusa fresenii Now. With some evidence of
the presence of this disease in the expanding period of the aphids
the epidemic occurs during the period of lessened food supply and
where the aphids are confined and crowded on a fewer number of
the citrus trees. Increased density of aphid population will in-
crease the disease.
A culture of fungus which may be the disease-producing organ-
ism has been secured. At present this culture has been non-spore
forming. Further studies are essential to secure the sporulation
of the fungus producing the disease on aphids, and to show its
adaptation to dissemination under grove practices.
The resting spore of the fungus has not been germinated. The
conditions imposed on this spore stage by the natural surround-
ings in the grove and the habits of the aphids, may shed some
light on the germination of it in the laboratory. From all the
evidence thus far secured there is every possibility of finding two
strains of the fungus (+ and -) the mingling of which, in the

Annual Report, 1929

same aphid's body, is responsible for the development of the
resting spore of Empusa fresenii Now.
In both the active spore stage and in the resting spore stage
there is an almost complete replacement of the interior body
materials, except muscular tissues, caused by the development
of the fungus. The death occurs at any time in this replacement,
but generally is delayed until the body of the aphid is packed full
of the fungous materials. What appears to be two types of hyphal
bodies have been observed in dissections of the diseased aphids
and in prepared stained slides. Further study as to the constancy
and nature of these hyphal bodies is essential. The nuclear con-
dition of hyphal bodies, conidia, gametes and resting spores has
been determined.
The passage of the nuclei into the young zygospore has been
observed. The matured zygospore is very heavy walled and con-
tains one-half the number of nuclei which are generally found in
the actively growing stages.
AVOCADO FRUIT SPOT
(State Project No. 18)
This project was made active on a partial basis after being
inactive for several years. A preliminary survey was made of
avocado diseases occurring in the avocado growing section of south
Dade County. This survey was used as a basis for determining
the principal diseases and the need for investigational work. Black
spot and scab were most important and some laboratory experi-
ments were conducted on the study of the causal organism.
It is suggested that the project be discontinued for the present.
ASPARAGUS FERN SURVEY
(State Project)
A complete survey of the Asparagus plumosus ferneries of the
State has been made by the Department of Plant Pathology during
the past two years. This has been done as a preliminary step
towards investigating some of the disease problems of this indus-
try. Funds for investigating the diseases of ferns will become
available on July 1, 1929, at which time one or more definite
projects will be outlined covering the work.
TRUCK CROP STUDIES
SEEDBED DISEASES
(Adams Project No. 6)
During the past year sweet potato seedbeds have been grown
and field plantings made for the purpose of gaining general infor-

Florida Agricultural Experiment Station

nation concerning the seasonal occurrence of the various diseases
of the host. Sclerotium rolfsii Sacc. was of considerable impor-
tance at the time of planting the field plots. The fungus attacked
the sets before they were well established, following transplanting
and caused a 40 percent loss of plants.
A seedbed and field plot was planted with seed of the various
cultivated cruciferous plants for the purpose of obtaining knowl-
edge concerning the seasonal development of diseases of these
plants. Downy mildew, Peronospora parasitica, and wire stem,
Rhizoctonia solani, were the two most important fungi found
causing damage; a large number of others were present, however.
This project is to be discontinued, since it is deemed more ad-
visable to carry out this type of investigational work in reference
to special problems or projects.

DOWNY MILDEW OF CUCURBITS
(Hatch Project No. 30)
The experimental work involving about five acres of commer-
cial plantings was conducted along lines similar to the work of
the previous season. The application of sprays and dusts was
delayed longer than for the previous year, the first application
being made when there were occasional blooming plants. At the
time of the first application on March 30 the first natural infec-
tion of the disease was collected. The first plots were picked
April 22 and the last picking was made May 13. The vines were
killed by the disease quickly; even the plots to which fungicides
were added succumbed.
The most outstanding results and conclusions are that fungi-
cides should be applied as soon as true leaves develop and should
be repeated weekly. The copper sprays and dusts were more
beneficial than sulphur.
Spraying and dusting with copper fungicides are good invest-
ments, even though no blight appears, because they produce
greener fruit and such fruit is more acceptable on the market
than fruit lacking good color.
The experimental work dealing with the effect of Bordeaux
spray on setting of fruit was continued along lines similar to
last year.
DOWNY MILDEW OF CUCUMBER
(Adams Project No: 19)
This project was not active last year. It is to be made more
active in future, however, and will deal with the effect of the

Annual Report, 1929

application of Bordeaux mixture on the control of this disease
with reference to the early setting of fruit.

BACTERIAL DISEASES OF CUCURBITS
(Adams Project No. 23)

The most pressing problems involved in this project have been
solved and it is recommended that the project be discontinued.
The project was initiated in the fiscal year 1912-13 and the lines
of work that have been followed are indicated in Bulletins 177
and 208 of the Agricultural Experiment Station series. A manu-
script dealing with the conclusion of the work has been sub-
mitted and will be published as Experiment Station Bulletin 207.

NAILHEAD RUST OF TOMATOES-CONTROL
(Hatch Project No. 115)

The application of fungicides for the control of nailhead rust
was conducted along lines similar to last year. The spraying and
dusting activities were centered around Homestead on the lower
East Coast where 12 acres of commercially grown tomatoes were
included in the experimental plots and in the Bradenton section
on the West Coast where duplicate experiments were conducted
on eight acres of tomatoes. Bordeaux sprays of various strengths,
copper and sulphur dusts of different kinds and sprays and dusts
were compared as to their relative value as fungicides and their
effects upon the plants. Since there was less than 1% of nailhead
infected fruit in any of the check plots in either locality, no infor-
mation was obtained with respect to this disease. Copper fungi-
cides were beneficial, however, in that they produced greener,
more healthy looking plants.

NAILHEAD RUST OF TOMATOES-CAUSE
(Adams Project No. 116)

The organism causing nailhead rust of tomatoes has been
grown in various environments and its rate of growth in relation
to temperatures and different hydrogen-ion concentrations ob-
tained. Its pathogenicity and parasitism have been established
through inoculation experiments and its host range quite defi-
nitely determined. This fungus has been compared with other
closely related fungi and the disease it causes compared with dis-
eases caused by these fungi. The organism and the disease it pro-

Florida Agricultural Experiment Station

duces are distinct. The early blight disease of tomato, eggplant
and potato are very similar and caused by the same fungus, which
is distinct from the nailhead rust producing fungus. These fungi
survive from one season to the next on wild hosts and in tomato
vines left in fields. Inoculation experiments show Earliana to be a
very susceptible variety and Marvel a very resistant variety with
the great number of commercial varieties placed between. Globe
and Cooper Special are not so susceptible as Earliana nor as
resistant as Marglobe, the latter being more susceptible to the
disease than Marvel.
STRAWBERRY DISEASES
(State Project No. 126)
(1) Leaf scorch (Diplocarpon earliana) was fairly abundant
during the summer of 1928. Alternate beds in the Strawberry
Laboratory nursery were sprayed with Bordeaux mixture 4-4-50
every 10 to 14 days, depending upon the frequency of rains. In
September when the plants were removed for fall setting those
from the sprayed beds were vigorous and free of scorch while
those from the unsprayed beds were much less vigorous and the
leaves were much spotted.
(2) Leaf blight (Dendrophoma obscurans) was active in some
fields throughout the year, and resulted in the killing of some
plants. Two growers attempted control of this disease with Bor-
deaux mixture 4-4-50 but were not successful.
(3) Leaf spot (Mycosphaerella fragariae) was prevalent in
some fields throughout the year. A survey showed that it was
more severe on some of the plants secured from Arkansas than
on those from Maryland. In one field, set in February, Maryland
plants were set in the midst of Arkansas plants. The latter leaf
spotted severely, whereas the former showed but little of the
disease. In previous tests at the Strawberry Laboratory, Mary-
land Missionary strawberry plants have been found to be quite
resistant to leaf spot. There may be an intravarietal difference
between the plants secured from the two states.

STRAWBERRY ANTHRACNOSE,
(State Project No. 127)
During the past year the work accomplished on anthracnose
was mostly confirmatory of the previous season's work. Isolations
were made from diseased strawberry runners, a complete descrip-
tive study made of the fungus and inoculation experiments car-

Annual Report, 1929

ried on during the fall and again in the spring. A fungus, Col-
letotrichum sp., has been definitely proven to be the causal organ-
ism. Species determination has not been accomplished, due to
the fact that the investigator has not had opportunity to compare
this fungus with other species of Colletotrichuni.

CRIMPS OR FRENCH BUD
(State Project No. 128)
The strawberry disease in Florida, designated under various
names as crimps, French bud, white bud, briar bud and red bud,
is probably identical with the dwarf disease in Louisiana and the
red plant disease in Great Britain and causes losses in individual
fields ranging from 0% to 75% and for the entire state about 2%.
The causal agent has not yet been proven beyond question, but
the results of observations and experiment strongly point to the
nematode Aphelenchus fragariae as the cause. This nema has
been found in large numbers, as high as 1,300, in crimped buds
but not in healthy ones. They are mostly ectoparasitic, occurring
in the axillary spaces of the leaves and in the folds of the young
leaves in the bud. However, it has not yet been definitely proven
that they do not occur in the youngest tissues of the bud. Inocu-
lations with these nemas as source of inoculum have produced the
disease in from 11 days to 5 months, whereas hypodermic inocu-
lations with the nematode-free juice from diseased plants as
source of inoculum have never produced the disease.
Flood water washing over or standing on the strawberry beds
has been observed to spread the disease. Developing runners
become infested with the nemas as they push through the axillary
spaces of the leaves. However, it is possible to find some diseased
plants which have some healthy runner plants. This is due to one
of two things, either the axillary spaces through which these run-
ners developed were not infested with nemas at the time or the
mother plant became diseased after the runner plants had become
established. There is no evidence that the disease is transmitted
through the runner, such as might be expected were it a virus
disease.
On moderately moist or dry land the spread of the disease from
plant to plant is very slow. The general spread of the disease is
due to transplanting from the nursery to the field plants which
are infested but have not at the time shown symptoms of the
disease. The disease appears at any time of the year that the
strawberry plants are putting on new succulent growth.

Florida Agricultural Experiment Station

Control is being attempted by roguing the diseased plants from
the nursery beds in the spring of the year and also removing them
from the fields as they appear.

INVESTIGATION OF THE IRISH POTATO DISEASE KNOWN AS
ALTERNARIA TUBER SPOTTING
(State Project No. 129)
Many cars of seed potatoes were inspected last season upon
arrival (December and January) by the Associate Plant Pathol-
ogist investigating the disease included in this project. The tuber
infection amounted to but a trace of a very mild type and conse-
quently produced practically no losses or consternation among the
growers. As the investigational work upon, this project has been
concluded, it is recommended that it be dropped.

POTATO DISEASES
(State Project No. 130)
Traces of early blight (Alternaria solani E. & M.) spotting and
small amounts of late blight (Phytophthora infestans de By.) rot
were noticed in seed potatoes imported into Florida from Maine
this season. In general, however, the quality of the seed stock
was excellent.
There was practically no seed-piece decay immediately after
planting and Rhizoctonia infestation (Corticium vagum B. & C.)
was light. Southern brown rot (Bacterium solanacearum E. F.
S.) was rather prevalent in some fields. Sclerotium rolfsii Sacc.,
while causing no serious losses, was more prevalent this season
than in any of the preceding five seasons. Early blight caused
practically no losses, and late blight reported first February 10,
in the Federal Point section, caused considerable damage. Virus
diseases present in small percentages were found in about the
usual amounts, depending somewhat upon the quality of seed
stock planted.
Experimental work with spindle tuber indicates that the dis-
ease can be spread at planting time by the cutting knife and pos-
sibly also by the picker planter. It was again demonstrated that
this disease causes great losses. The yields from all diseased
spindle tubers were compared with those from all healthy tubers
and percentage decreases ranging from 75% to 84% in prime
potatoes and from 17% to 37% in seconds were noted. It was also
demonstrated that seed-piece decay is a factor when dealing with
the spindle tuber disease.

Annual Report, 1929

LATE BLIGHT DISEASE OF POTATO
(State Project No. 131)
Fortnightly and weekly applications of a 20-80 copper-lime dust
were compared with no dusting in the late blight control experi-
ments of this season. Considerably less dust was applied per
application where the applications were made weekly. A total of
70 pounds were applied per acre where applied every fortnight,
and 96 pounds where applied every week.
The vines dusted every week matured about two weeks later,
and those dusted fortnightly about one week later than the non-
dusted. But 31/2% and 4% increases over the undusted were
obtained from the plots dusted weekly and fortnightly, respec-
tively. These increases are hardly significant.

RHIZOCTONIA CONTROL
(State Project No. 132)
Seed treatment experiments were conducted as in previous
seasons to determine the effect on Rhizoctonia control and on yield.
Two widely separated plots consisting of 10 replications of 27
hills per treatment were planted where cold corrosive sublimate,
hot formaldehyde, and dip-dust were used as treatments. Only
tubers covered with sclerotia were treated and were compared
with clean untreated, clean treated (corrosive sublimate) and dis-
eased untreated samples. A very low percentage of stem lesions
was observed when the plants were about four inches high, but the
actual injury caused was very slight. Practically no Rhizoctonia
hills with aerial tubers were observed at maturity. Significant
increases in yield were not obtained with any of the treatments
and dip-dust gave evidence of decided injury.

CORN DISEASE INVESTIGATIONS
(Purnell Project No. 118)
Three diseases of corn being investigated at this time are
Diplodia dry rot, Fusarium dry rot, and Physoderma disease.
Diplodia ear, stalk and root rot of corn in Florida is caused by
Diplodia zeae Ev., D. macrospora Earle, and D. frumenti Ell. and
Ev. Ears inoculated with D. natalensis Ev., D. tubericola Ell. and
Ev. and D. gossypina Cke. were also rotted by each of these spe-
cies. The Diplodia rots reduce yield because of severely rotted
ears discarded at harvest time, weakened plants resulting from
stalk infections and poor stands resulting from the use of Diplo-

Florida Agricultural Experiment Station

dia infected seed. It is estimated that the disease caused a 5 per-
cent reduction in the yield of corn in Florida in 1928.
Fusarium dry rot:-Moisture and temperature conditions in
Florida are especially favorable for the Fusarium disease of corn,
which is the most important ear rot disease in the state. An
examination of 1,500 ears showed that 3.3% were wholly rotted
by Fusarium spp. Fusaria were commonly associated with weak
and dead kernels in germination studies made on 1,650 ears col-
lected from 14 counties in the state. Germination studies also
show that kernels are invaded by non-parasitic as well as parasitic
species of Fusarium.
Fusarium moniliforme Sheld., isolated from various depths in
the soil, have proven to be parasitic on ears of corn. Tests are
now in progress that will show the value of selection of nearly
disease-free seed and the use of organic mercury dust compounds
in controlling seedling diseases.
The Physoderma disease of corn, which is caused by the fungus
Physoderma zeae-maydis Shaw, is generally distributed through-
out the state. It affects the leaves and culms of plants and, in
severe cases of infection, lodging of the stalks occurs. During the
1928 season 50% of the plants in some fields were infected with
the disease and it was estimated that there was a 15% infection
for the state as a whole. Numerous varieties and inbred lines of
corn grown in the experimental plots at Gainesville appeared to
differ in the resistance to the Physoderma disease in 1928. A
number of inbred lines are being grown this year under epidemic
conditions in an attempt to isolate resistant lines which can be
used to create resistant synthetic varieties.

DISEASES OF PECAN TREES
(State Project No. 4)
Pecan Scab. Both dusts and sprays were used in controlling
pecan scab in experimental plots during 1928. The total rain-
fall for the season was 85.66 inches, or 31.16 inches over normal.
This, coupled with the usual summer temperatures, made ideal
weather conditions for the growth and spread of scab. Six ex-
periments were conducted and all were failures insofar as show-
ing a profit from controlling scab were concerned, as the crop
harvested was too small to cover the cost of the work. This was
due both to a light set in the spring and to the storms which de-
stroyed a large part of the crop. During the winter, work on
the winter stage of the fungus was continued but with no definite

Annual Report, 1929

results. The annual survey showed that the Van Deman was less
susceptible than usual, other varieties remaining about the same.
During the year the Board of Commissioners of Jefferson
County erected a new laboratory building on a site of between
three and four acres south of Monticello. All equipment was
moved to this new building on July 1, 1929, and it will be pos-
sible to carry on additional lines of work with the increased
facilities thus provided.

PROJECTS DROPPED
For various reasons it has been necessary to discontinue or sus-
pend certain projects in this department. A list of them, with
pertinent comments, is given here.
Anthracnose, State Project No. 2, no active work for several
years past.
Bacterial diseases of solanaceous plants, Adams Project No. 5.
No investigational work of an intensive nature for seven years;
being re-outlined and changed from Adams to state funds, given
a new number, and will be carried on at Hastings.
Phomopsis of eggplant, State Project No. 15, no active work
for past several years, but an important problem for future.
Avocado scab, State Project No. 17, no active work for some
time.
Citrus canker, Hatch Project No. 29, dropped for the reason that
no canker is known to exist in Nature in the State, due to effective
eradication by State Plant Board.
Diseases of potatoes, State Project No. 31, originally approved
in 1923-24, included all investigational work on Irish potatoes;
now covered by Projects Nos. 129, 130, 131, and 132.
Citrus blight, State Project No. 32, has not been active during
the present year, except for observational information obtained
from budded and reset trees; a final, full report of the work is in
preparation.
Strawberry diseases, State Project No. 113, originated in 1925,
decentralized in 1927, sub-divided into Projects Nos. 126, 127,
and 128, which are now being carried forward.

Florida Agricultural Experiment Station

THE CITRUS EXPERIMENT STATION

Wilmon Newell, Director.
SIR: I submit the following report of the Citrus Experiment
Station at Lake Alfred for the fiscal year ending June 30, 1929.
Respectfully,
J. H. JEFFERIES,
Superintendent.

CITRUS PROGENY AND BUD SELECTION
(State Project No. 26)
The citrus progeny grove, a collection of carefully selected
varieties and strains, consisting of 36 strains of 10 varieties of
oranges, 11 strains of grapefruit, 3 strains of 2 varieties of tan-
gerines, and 2 strains of tangelos, has been maintained in a state
of satisfactory growth.
This planting also contains some budded trees of "sports" which
are being grown for the purpose of definitely showing the value
of careful bud selection.
Citrus growers and nurserymen have, in this grove, a source of
supply of budwood from trees of known variety, production and
quality.

PROPAGATION EXPERIMENTS WITH CITRUS PLANTS OF
VARIOUS KINDS
(State Project No. 34)
This project has not been active during the year except that the
work reported a year ago has been amplified to some extent.

TESTING OF INTRODUCED AND NEW VARIETIES AND
HYBRIDS OF CITRUS AND NEAR CITRUS
(State Project No. 35)
Observations of the collection of new citrus species, varieties,
hybrids, and near citrus, 54 in number, show a wide variation in
degree of hardiness, adaptability and thrift. Six of these have
shown themselves to be valuable acquisitions as ornamentals.

Annual Report, 1929

COVER CROP AND GREEN MANURE STUDIES IN CITRUS
GROVES
(State Project No. 83)

The citrus cover crops experimental work, as started in 1925
and outlined in the 1926 annual report, was continued with very
satisfactory results. Crotalaria striata again yielded the greatest
amount of green and air dried material to turn back to the land
for soil improvement.
No material difference can be noted between the trees of the
variously cover-cropped blocks except that those in the block
where Crotalaria is used as the cover crop are noticeably larger
and the foliage is a deeper green than those of other cover crop
blocks. The trees in the clean cultivated block continue to show
dieback and poor growth.
The comparative yields of the different cover crops for the
past four seasons are given in the following table:

Yield of Cover and Green Manure Crops Grown at Citrus Experiment Station,
Lake Alfred, Florida-Agronomy Department-Soil Fertility Studies.

Cover Crops
Used

Crotalaria striata
Velvet Beans.. .
Beggarweed ....
Cowpeas .......
Natal Grass.....
Diversified blk.
Rotated to
above crops..

Po

1925
7656
2212
3062
2211

unds per Acre Top Growth
Air Dried

1926 1927
4835 2401
2526 2295
2178 failure
1350 1147
3060 1 4292

3400
Natal
Grass

1360
cow-
peas

1928
4080
2380
3400
3400
3400

2040
Velvet
Beans

4-Year
AveraLe
4743
2353
2160
2027
*3595

'2266

Percent
Nitrogen
8%
Moisture
Basis

z.177
1.998
1.207
1.662
1.081

Pounds
Nitrogen
in Average
Top Growth
of Crops
8% Moisture
Basis.
103.3
47.0
26.1
33.7
38.9

*3-Year average.
Tree growth is shown clearly by the following tables which give
the diameter of the trees in 1925 and 1929:

Effect of Cover Crops on the Growth of Citrus Trees-Tree Diameter in
Inches-Citrus Experiment Station, Lake Alfred, Florida-1925 to 1929-
Agronomy Department-Soil Fertility Investigations.
Growth of Citrus
Cover Crops Used Trees Inches Rank
_1925 1929 Increase
Crotalaria striata .................. 869 3.203 2.334 1
Velvet Beans ................... .. .863 3.021 2.158 3
Beggarweed ..................... .859 3.053 2.194 2
Cowpeas ......................... .867 2.941 2.074 5
Natal Grass ...................... 1 .865 2.950 2.085 4
Clean Cultivation (no cover crop)... I .902 2.872 1.970 6

Florida Agricultural Experiment Station

The first crop of fruit produced by the trees in this cover crop
experiment has been harvested and weighed. Individual tree pro-
duction is being kept. This season the trees in the Crotalaria
striata cover crop block yielded the greatest. However, this may
not mean a great deal, since the comparative yield of fruit from
young trees the first few years may be misleading. Then, too,
it would hardly be time yet to judge the effect which the different
cover crops may have on tree yield.
One minor change has been made in the cover crop experiment
this year. This change involves one block of trees formerly cover
cropped to cowpeas. From now on this block of trees will be cover
cropped to Crotalaria and the Crotalaria used as a mulch around
the trees. Some Crotalaria will also be grown on another area
and hauled in and placed as an additional mulch on this block.

CITRUS VARIETY TEST INCLUDING ROOTSTOCKS
(State Project No. 102)
In addition to the more common rootstocks, which include rough
lemon, sour orange, and P. trifoliata, test plantings of citrus root-
stocks now include sweet, willow-leaf sour, and bitter-sweet
orange, Cleopatra and willow-leaf mandarin, pink shaddock, Rusk
citrange, and calamondin. Commercial varieties of citrus have
been budded on these rootstocks for distribution and test in the
various citrus sections of the state.
The trees in the variety grove are showing a very satisfactory
growth. This planting consists of 36 varieties of oranges, 6 vari-
eties of grapefruit, 3 varieties of tangerines, 6 varieties of lemons,
citron, calamondin, and several hybrids. Most of these are budded
on rough lemon rootstocks, although some are on sweet seedling,
bitter-sweet, and Cleopatra mandarin roots.
The Meyer lemon has fruited for the second year. Its growth
and fruit quality show it to have considerable merit.

Annual Report, 1929

THE EVERGLADES EXPERIMENT STATION
Wilmon Newell, Director.
SIR: I submit the following report of the Everglades Experi-
ment Station at Belle Glade for the fiscal year ending June 30,
1929.
Respectfully,
R. V. ALLISON,
Soils Specialist in Charge.

At the close of the fiscal year 1928, a small but effective working
staff had been gathered at the Everglades Station and a consid-
erable amount of detailed soils and crops work in the fields and
in the laboratories was under way. Plans for the expansion of
this work were made for the present fiscal year and these plans
were being carried out effectively up to the date of the storm of
August 8, 1928. No serious damage from wind resulted from this
first storm of the year, but the heavy rainfall accompanying it
raised the level of the water in the soil and handicapped field
operations to a considerable extent. Just as conditions were re-
turning to normal, the hurricane of September 16 and 17 arrived,
bringing with it into the Upper Glades indescribable conditions
of flood and destruction.
THE SEPTEMBER HURRICANE
No detailed regional discussion of conditions incident to this
storm will be given in this report. It is thought important, how-
ever, to refer to them at least insofar as they were found to affect
the Experiment Station and its work for the year.
The hurricane reached the Everglades Station on the evening
of September 16, 1928, and continued, with high winds and heavy
rainfall, through the 17th. The station's anemometer was de-
stroyed at 8:18 p. m. on the 16th, its last recorded movement
showing a wind velocity of 92 miles per hour. Conservative esti-
mates would say that during subsequent periods of maximum
intensity the wind reached velocities up to 125-135 miles per
hour. The wind direction during the first half of the storm was
N. E. and varied to N.-N. W. A definite lull occurred at about
10:00 p. m. and lasted about an hour. During the second half of

Florida Agricultural Experiment Station

the storm, and following the
lull, the wind direction was S.
W. varying to S.-S. E. This
area, from the above indica-
tions, was directly in the path
of the storm center.
A photographic reproduction
of the curve recorded by the sta-
tion barograph during the storm
period is shown in Figure 2. The
time at which the anemometer
was blown out of commission
is shown by a cross on the curve.
The total rainfall received in
the rain gauge, from which the
top was blown away, during the
period September 17-21, was
11.35 inches. This figure is
uncertain as representing the
rainfall accompanying the
storm, both on account of the
loss of the top of the rain gauge
and on account of the obliquity
of the movement of the larger
part of the rainfall under such
severe storm conditions. It is
also true that after the surface
of the ground became covered
with water, the water was
picked up by the wind and again
whirled into the air.
During the course of the
storm a short breach appeared
in the west side of the dike sur-
rounding the Station property
and it was particularly on ac-
count of this break, together
with the high head of water
that prevailed on all sides of the
Fig. 2.-A photographic reproduc-
tion of the barographic record at the
Everglades Experiment Station for
the week ending September 17, 1928,
showing the violent fall in pressure
that accompanied the storm of the
16th.

Annual Report, 1929

comparatively small area representing the present property of
the Station now under development, that it was found impossible
to secure local relief by operating the small pumping unit avail-
able.
The surface of the land was first flooded to a depth of about
three feet by the morning of September 17. The water rather
quickly subsided to a depth of two feet over the surface of the
land but it was not until December 4 that the land was again out
of water. The flooding of the land, including the entire Upper
Glades, resulted from flood waters received from Lake Okeecho-
bee. The muck dike along the southern and southeastern edges
of the lake proved an inadequate barrier to the wave effect of
the lake's water under the influence of the wind during the first

U

U I

Fig. 3.-View of the Everglades Experiment Station grounds following
the storm of September 16, 1928. (Taken 9/18/28 from the roof of the lab-
oratory building, looking south over the greenhouse in the direction of
Miami.)
half of the storm. It was during this same period that the small
breach was developed in the west dike of the Experiment Station,
already referred to.
In consequence of the long exposure to flood conditions, all field
work in progress was completely destroyed. On account of heavy
surface washing and drifting of soil material in many places, a
number of experimental units, particularly those involving small
plot studies, had to be abandoned, at least insofar as the original
treatments were concerned.
The most serious physical damage done by the storm to the
buildings was the complete destruction of one five-room bungalow,

I

P~

Florida Agricultural Experiment Station

two labor cabins, one garage, and the west section of the green-
house. The roofs of practically all buildings, with the exception
of two bungalows and the service house of the greenhouse, were
badly damaged and had to be restored. Likewise considerable
damage was done to the walls of the several garages and sheds
that were not completely destroyed. The two-story boarding
house building was also badly wrecked and was later torn down.

REBUILDING AND IMPROVEMENT OF PROPERTY
With the authority of the Board of Control, a rebuilding pro-
gram was planned and carried out as soon as conditions had
returned to normal. This has included the repairing and restor-

Fig. 4.-View of central and west sections of greenhouse at the Ever-
glades Experiment Station following the storm of September 16, 1928. The
high water mark can be noted about seven inches above the bench on jars
on the left side. Picture shows characteristic manner in which the western
section was crushed in, doubtless due in large part to early blowing away
of one of the ventilators through faulty catch. Comparatively little phys-
ical damage was done to the other two sections of the structure.

ing of all damaged buildings as fully as possible; the construction
of two new five-room bungalows, two new implement shelters and
a stock barn. The bungalows are of the same design as those
already built but are supported on heavier concrete foundations
and have heavier framing material and are more thoroughly

Annual Report, 1929

braced throughout. Heavy anchor rods also extend from the
rafter plates through the heavy concrete sills of the foundation.
In reroofing the dwelling houses and the laboratory building,
pressed asbestos cement shingles (16"x16" Eternit) were used.
These were also used on the new bungalows. The newly con-
structed implement shelters, 24'x60', are of heavy wooden frame
construction supported upon and tied to reinforced concrete
piers that rest upon the rock. The roof and sides of these build-
ings, like the others, are built of corrugated iron. The stock
barn, 36'x60', (Fig. 5) is a two-story frame structure of rather
heavy construction with all joints in the main framework bolted
instead of nailed. The sides are covered with 5/8" Bond siding

Fig. 5.-Cattle barn at the Everglades Experiment Station, built in June,
1929. Good pasture of Dalli grass is shown in the foreground.
and the roof with gravel paper. The foundation consists of a
heavy reinforced 8"x12" concrete beam poured with the 8"x8"
piers at 71/2 foot intervals that rest upon the rock at a depth of
seven feet. A double row of similar piers located at the same
intervals support the interior of the building. Heavy anchor rods
extend from the rafter plates of the structure down to and
through the concrete sill. The barn is well ventilated and
screened to protect animals from insects.
The work of reconstruction upon the greenhouse was begun
before the close of the year but it was not found possible to com-
plete it by July 1.

Florida Agricultural Experiment Station

Naturally the canals and drainage lines of the property were
left in bad shape following the storm. A heavy 5,000-gallon cen-
trifugal pump mounted to drive directly from a 42 h.p. Conti-
nental motor has been ordered to clean out the ditches but this
equipment has not arrived at the close of the year.

INVESTIGATIONAL WORK

Following the storm of September 16 and 17, 1928, much of the
investigational work of the Station was, of necessity, abandoned.
The research staff was also reduced through the resignation of
Dr. J. L. Seal, Associate Plant Pathologist, J. H. Hunter, Assistant
Agronomist, and James Naftel, Laboratory Assistant. The fol-
lowing report covers the work that it has been possible to carry
forward during the part of the year following the storm.

FORAGE, TRUCK AND FIELD CROP TRIALS
(State Project No. 84)
All field work connected with this project was abandoned after
the storm. With the resignation of Mr. Hunter, Assistant Agron-
omist, it became impossible to initiate new work and the project
has been inactive for the greater part of the year.

FRUIT AND FOREST TREE TRIALS
(State Project No. 85)

Fruit and forest tree plantings were destroyed by the storm.
New plantings are planned but have not yet been made. This
project has been inactive during the year.

FIELD FERTILIZER EXPERIMENTS
(State Project No. 86)

Most work with regular fertilizer materials or other soil amend-
ments at the Experiment Station has been upon sugarcane and
peanuts. In the instance of outlying areas it has been upon
sugarcane and beans. At the Experiment Station, however, a
number of other crops including corn, rape, potatoes, sunflowers,
snap beans, velvet beans, soybeans, cowpeas, etc., have been
studied during the year to.a certain extent. In the near future,
it is hoped to get on with systematic studies of this type upon
most of the forage crops. It is unfortunate that so much of this
work, upon which considerable progress had been made in the

Annual Report, 1929

field, was entirely destroyed at the time of the storm. This in-
cluded studies with special elements and certain combinations of
them upon sugarcane, peanuts and other plants as well as other
studies with regular fertilizer materials upon a number of crops.
Likewise important rotation studies inaugurated by the Agron-
omist in which certain features of soil treatment were incorpo-
rated, were lost.
Work with Sugarcane.-The work upon sugarcane has largely
consisted of (a) varietal tests upon general soil treatments and
(b) fertilizer tests in which the study of special elements has
found an important place.

4i

Fig. 6.-Sugarcane of the Coimbatore group was found to be able to sur-
vive under storm conditions. The stalks of Co. 281, shown here, were
growing on ground which had its surface flooded for some three months.
(Cf. Fig. 7.)

In the varietal tests with sugarcane upon sawgrass land which
are being carried out in a cooperative way with the United States
Department of Agriculture, considerable information was ob-
tained following the storm upon the comparative strength and
vigor of different varieties to withstand such conditions as were
imposed at that time. The canes of the Coimbatore group were
found to stand out in quite a remarkable way. Figure 6, for in-
stance, shows Co. 281 under conditions of surface flooding which
continued for some three months. Following the subsidence of
the water all buds upon physically sound stems were found to be
hard and viable by test and the germination of underground buds

Florida Agricultural Experiment Station

was found to be prompt and normal in every way (Fig. 7). In
the case of all varieties from which stock material could be saved
for the purpose (Fig. 8) plantings were made as soon as possible
upon higher ground beyond Belle Glade and returned to the station
directly field conditions permitted their reestablishment.
In reestablishing the fertilizer tests with sugarcane at the Ex-
periment Station all canes were removed from the fertilizer tests,
including the underground portions of the cepas, and destroyed
after sufficient of such varieties as were returned to the tests had

Fig. 7.-Growing cane which resulted from the planting of some of the
stalks shown in Fig. 6, showing that the Coimbatore cane which had been
flooded for three months remained viable.

been selected. Stocks of a few additional varieties to replace those
discarded were obtained through the courtesy of Mr. F. E. Bryant
at Canal Point. In these a response of particular interest that
had been observed prior to the storm, aside from that to copper,
was that to potash applications.
The larger fertilizer tests at Canal Point experienced the same
conditions of exposure as those at the Station, though the period
of flooding was somewhat shorter. Crystalina was so adversely
affected that it was entirely removed from all plots at the time
of rehabilitation and Co. 281 substituted later. The other two
varieties included in the Canal Point tests, P. O. J. 36-M, and
P. O. J. 2725 stood the exposure and, with some replanting, were
brought back to a stand. A further fertilizer treatment was also
given, though with a reduction of 50% in the standard applica-

Annual Report, 1929

tion of superphosphate, since this material was found to produce
rather serious injury to all varieties.
Continuation of Studies with Special Elements.-The detailed
studies with special elements suffered particularly, since the move-
ment of such exceedingly small quantities of certain of these
chemicals into untreated areas is able to produce extraordinary
effects. The special series of peanut plots which were centered
around soil treatment with a combination of copper and zinc sul-
fates had to be abandoned. Other studies of a similar nature
with sugarcane were left in an equally disturbed condition by the
storm.
Work with manganese has been continued during the year and
results of unusual importance have been obtained. This is espe-
cially true in the case of beans upon burned soils where the re-
action is excessively alkaline in consequence of the burning. Fur-
ther striking results also have been obtained in the continuation

Fig. 8.-Preparing small lots of sugarcane varieties from the various
plantings at the Everglades Experiment Station for temporary removal to
higher ground in order to preserve the stock.

of these studies upon the use of a combination treatment of copper
and manganese on certain soils where treatment with either alone
has given results varying from those that are decidedly inferior
to poorer responses that represent complete failures. During the
past season a decided response of sugarcane to manganese in the
course of such studies was observed for the first time.

Florida Agricultural Experiment Station

INSECT PESTS AND PLANT DISEASES AND THEIR CONTROL
(State Project No. 87)
Work on plant diseases, particularly those of beans and potatoes,
had been carried forward by Dr. J. L. Seal and plans for the work
during the current fiscal year had been made. The storm, how-
ever, made it impossible to carry out this work and Dr. Seal's
resignation left this phase of the project without a leader. No
investigations of insect pests have been initiated to date but it is
planned to start active work on both phases of this project as
soon as possible.
SOIL INVESTIGATIONS
(State Project No. 88)
As soon after the first of the year as water conditions in the
Upper Glades would permit, Dr. A. P. Dachnowski-Stokes came
down from the Bureau of Chemistry and Soils, United States De-
partment of Agriculture, and spent several weeks at the Station
in continuation of the cooperative work begun during the pre-
vious winter. The soils of the Upper Glades have been emphasized
in this work and lines of soundings and profile examinations have
been run in a number of directions from the Lake, particularly
along the main canals. The principal line, however, represents a
practically complete traverse of the Upper Glades, from a point
well into the margin on the east along the West Palm Beach High-
way out into the western margin about five miles south of Clewis-
ton. The positions of these lines will be shown upon maps to be
published later.
A number of type profiles were excavated in connection with
this work and brought to the laboratory for study. Rather com-
plete chemical analyses have been made of these and shrinkage
and volume weight studies have also been stressed. Some prog-
ress was also made upon the preparation of alcoholic extracts of
certain sections of the local profile, following the procedure of W.
S. Smith in Holland, this work being done by Dr. R. M. Barnette
of the Chemistry Department of the Main Station during a six-
weeks visit to the Everglades Station.
The problem of burned soils has been given further attention in
areas adjacent to the lake. These studies have also been ex-
tended here at the Experiment Station, where important results
have been obtained upon burned soil with the use of manganese
and particularly with a combination treatment of copper and
manganese. It has been observed that burning in this way alle-
viates to a marked extent the need for copper treatment. In cer-

Annual Report, 1929 95

tain cases studies have been made by treatment of such soils with
sulfur and with sulfuric acid and notable plant responses have
been obtained under conditions where manganese deficiencies of
the nature referred to have been found to occur.

DRAINAGE STUDIES
(State Project No. 89)
Investigations upon the movement of underground water have
been continued through the year, so far as existing conditions
would permit. In the course of these studies certain new lines of
observation wells have been established particularly to record the
movement of the water in the soil under conditions of heavy pump-
ing from areas adjacent to main drainage canals which developed
increasing heads of pressure against the land with the progressive
lowering of the water table within the area. Such a line was estab-
lished through the courtesy of Mr. F. E. Bryant of the Southern
Sugar Company in one of the pumping units at Canal Point that
discharges into the West Palm Beach Canal. These and other
studies have been useful in showing the actual position assumed
by the water table in the soil in relation to an outside head of
pressure and have demonstrated the entire feasibility of local
drainage operations in the Everglades, though marginal seepage
effects must always be taken into consideration.
In connection with this work, studies upon the establishment
and deportment of mole lines or formed lines of seepage through
the soil have been continued during the year. With proper appli-
cations it would appear that the mole principle might be made an
unusually effective and economical agent in the solution of one
of our most important problems, namely, a closer manipulation
of the water table in organic soils under conditions of cultivation.

SOILS AND CROP STUDIES, INCLUDING ROTATION, FERTILIZER
AND CULTURAL PRACTICE EXPERIMENTS
(State Project No. 90)

No active work under this project has been conducted during
the year following the storm of September, 1928, and the resig-
nation of Assistant Agronomist J. H. Hunter.

GREENHOUSE AND LABORATORY WORK
The work in the greenhouse and laboratory during the year
has been concerned largely with the checking up of certain of the

96 Florida Agricultural Experiment Station

field results, particularly in the relation of burned soils to plant
response and the soils phases of the problems associated with bean
failure in the lake region. As in the case of the field work, con-
siderable delay and loss of work was experienced in consequence
of the storm.
Some progress also has been made in the study of the physio-
logical relation of copper and other ions to plant development in
the local sawgrass soils that was begun during the fall of 1927.
This work is centered around the direct injection of these special
ions into the plant system in a number of ways in comparison to
regular soil treatments. In this way any effect they are found
to exert upon plant development under these conditions in such
a soil may be regarded as independent of the secondary effects
such chemical treatments may bring about in the soil environ-
ment. This work is being closely associated with that already
referred to upon alcoholic extraction.

Annual Report, 1929

THE TOBACCO EXPERIMENT STATION
',ilmii,,,, Newell, Director.
SIR: I submit the following report of the Tobacco Experiment
Station at Quincy for the fiscal year ending June 30, 1929.
Respectfully,
W. B. TISDALE,
Acting in Charge.
FIELD AND LABORATORY STUDIES OF TOBACCO
DISEASES
(State Project No. 25)
Investigations under this project have been limited primarily
to a study of a leaf spot disease of cigarette tobacco caused by a
species of Alternaria. The important phases of this disease, ex-
cept methods of control, have been worked out.

Fig. 9.-Contrast of resistant strain 1-1-3g-5-4-3 (left) with susceptible
Connecticut Round Tip (right), growing on black shank-infested soil, 1929.

Florida Agricultural Experiment Station

Other work on tobacco diseases which has been done during
the year has been concerned with identifying disease specimens
brought to the laboratory by tobacco growers. Most of the dis-
eases which caused trouble were confined to the plant beds and
of these wildfire (Bacterium tabacum Wolf & Foster) and scab
(Septomyxa affinis (Sherb.) Wollen.) were most prevalent. Com-
paratively little damage was caused by these diseases on the
whole, however. Work on other diseases was discontinued on
January 1, 1929, when Dr. Tisdale was transferred to the Main
Station at Gainesville.

VARIETY TESTS OF CIGAR WRAPPER TOBACCO FOR
RESISTANCE TO BLACK SHANK
(Phytophthora Nicotianae Breda de Hann.)
(State Project No. 33)
The trials of different varieties and strains of cigar wrapper
tobacco for resistance to black shank were limited to two acres
of land on the station farm. This land had been cropped to to-

Fig. 10.-Contrast of resistant strain R-28-15 (left) with susceptible Con-
necticut Round Tip (right), growing on black shank-infested soil, 1929.

Annual Report, 1929

bacco previously for five successive years, and is thoroughly in-
fested with the fungous parasite which causes black shank. All
told, 150 selfed selections of tobacco were tested on the plot. Two
of these were strains of cigarette tobacco and a few of the others
were selections of certain varieties of wrapper tobacco. A ma-
jority of the strains were selections from crosses, varying from
the second to sixth generation from the cross.
Weather conditions have been favorable for growth of the
crop and also for development of the black shank disease. The
Connecticut Round Tip variety was used for check rows, as it is
100% susceptible to black shank. These rows of Connecticut
Round Tip are practically 100% dead, while several strains of
numbers 301, R, 1, and 94 are more than 95% healthy and have
produced a good yield of a desirable type and quality of leaf.
Their general appearance on June 7 is shown in Figs. 9-13. Num-

Fig. 11.-Contrast of resistant strain 301-4-5-1-7-3
(right) with susceptible Connecticut Round Tip (left),
growing on black shank-infested soil, 1929.

	Front Cover
	Title Page
	Table of Contents
	Letter of transmittal
	Personnel
	Report of director
	Report of business manager
	Publications
	Library
	Agricultural economics
	Agronomy
	Animal husbandry
	Chemistry
	Cotton investigations
	Entomology
	Home economics
	Horticulture
	Plant pathology
	The citrus experiment station
	The Everglades experiment...
	The tobacco experiment station
	Index