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 Front Cover
 Title Page
 Table of Contents
 Letter of transmittal
 Administration
 Report of director
 Report of business manager
 Report of editor
 Report of agronomist
 Report of animal industrialist
 Report of chemist
 Report of cotton investigation...
 Report of entomologist
 Report of associate horticultu...
 Report of plant pathologist
 Report of veterinarian
 Report of agricultural economi...
 Report of librarian
 Report of home economist
 Report of the citrus experiment...
 Report of the tobacco experiment...
 Report of the Everglades experiment...
 Index


UF FLAG IFAS



Report for the fiscal year ending June 30th
ALL VOLUMES CITATION SEARCH THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00005173/00002
 Material Information
Title: Report for the fiscal year ending June 30th
Physical Description: v. : ill. ; 23 cm.
Language: English
Creator: University of Florida -- Agricultural Experiment Station
Publisher: University of Florida
Place of Publication: Gainesville Fla
Creation Date: 1927
Publication Date: 1905-1944
Frequency: annual
regular
 Subjects
Subjects / Keywords: Agriculture -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
serial   ( sobekcm )
 Notes
Statement of Responsibility: Florida Agricultural Experiment Station.
Dates or Sequential Designation: 1905-1944.
 Record Information
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: aleph - 002452807
oclc - 12029638
notis - AMF8112
System ID: UF00005173:00002
 Related Items
Preceded by: Report for financial year ending June 30th
Succeeded by: Annual report for the fiscal year ending June 30th

Table of Contents
    Front Cover
        Front Cover
    Title Page
        Page 1
    Table of Contents
        Page 2
    Letter of transmittal
        Page 3
    Administration
        Page 4
    Report of director
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
    Report of business manager
        Page 12
        Page 13
        Page 14
    Report of editor
        Page 15
        Page 16
    Report of agronomist
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
        Page 26
    Report of animal industrialist
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
    Report of chemist
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
    Report of cotton investigations
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
    Report of entomologist
        Page 43
        Page 44
        Page 45
        Page 46
        Page 47
        Page 48
        Page 49
    Report of associate horticulturist
        Page 50
        Page 51
        Page 52
        Page 53
        Page 54
        Page 55
        Page 56
        Page 57
        Page 58
        Page 59
        Page 60
        Page 61
    Report of plant pathologist
        Page 62
        Page 63
        Page 64
        Page 65
        Page 66
        Page 67
        Page 68
        Page 69
        Page 70
        Page 71
        Page 72
        Page 73
        Page 74
        Page 75
        Page 76
        Page 77
    Report of veterinarian
        Page 78
        Page 79
        Page 80
        Page 81
        Page 82
        Page 83
    Report of agricultural economist
        Page 84
        Page 85
        Page 86
    Report of librarian
        Page 87
        Page 88
    Report of home economist
        Page 89
        Page 90
        Page 91
    Report of the citrus experiment station
        Page 92
        Page 93
        Page 94
        Page 95
        Page 96
        Page 97
    Report of the tobacco experiment station
        Page 98
        Page 99
        Page 100
        Page 101
        Page 102
        Page 103
    Report of the Everglades experiment station
        Page 104
        Page 105
        Page 106
        Page 107
        Page 108
        Page 109
        Page 110
        Page 111
        Page 112
        Page 113
        Page 114
        Page 115
        Page 116
        Page 117
        Page 118
        Page 119
        Page 120
        Page 121
        Page 122
    Index
        Page i
        Page ii
        Page iii
        Page iv
        Page v
Full Text








UNIVERSITY OF FLORIDA


AGRICULTURAL EXPERIMENT

STATION




REPORT FOR THE FISCAL YEAR ENDING
JUNE 30, 1927







CONTENTS

REPORT OF DIRECTOR ............................ ...... .. ---. --------.------ ---.--.--- ... 5R
Introduction, 5R; Changes in Staff, 6R; Project List, 8R.
REPORT OF BUSINESS MANAGER ................................ -------- 12R
REPORT OF EDITOR .......-.........--- ... -. ......---.--- ..-------... .. ............... 15R
REPORT OF AGRONOMIST .....--..... --.........- .... ---.........- ....... ---- 17R
Winter Leguminous Plants, 17R; Crotalaria, 19R; Fertilizer Ex-
periments, 21R; Crop Rotation Studies, 21R; Lawn Grass Stu-
dies, 22R; Pasture Grass Studies, 22R; Cover Crop and Green
Manure Studies, 23R; Napier Grass Studies, 25R.
REPORT OF ANIMAL INDUSTRIALIST .................. ..................----- -- -----------... 27R
Feeding Tests, 27R; Corn Silage vs. Napier Grass Silage for
Milk Production, 30R; Swine Feeding, 31R.
REPORT OF CHEMIST ...........................----.............. -----.... -----.. ------...... 33R
Dieback, 33R; Soils Studies, 33R; Nutrition Studies, 34R; Miscel-
laneous, 37R.
REPORT OF COTTON INVESTIGATIONS ..........--......-- ......-............. 38R
Pathology and Physiology, 38R; Breeding, 39R; Boll Weevil In-
vestigations, 40R.
REPORT OF ENTOMOLOGIST ........................... ...... .......-- .--------....... 43R
The Green Citrus Aphid, 43R; Root-knot, 45R; Florida Flower
Thrips, 46R; Introduction of Beneficial Insects, 47R; Pecan In-
sect Investigations, 47R.
REPORT OF ASSOCIATE HORTICULTURIST .....-...---.......... -----.................. 50R
Splitting of Oranges, 50R; Cold Injury-Citrus, 52R; Fruit Pro-
duction, Citrus, 52R; Test Grounds, 53R; Studies on Truck
Crops, 56R; Pecan Investigations, 59R.
REPORT OF PLANT PATHOLOGIST ..----............................. ......-..-...---.---.... 62R
Citrus Canker, 62R; Scaly Bark Investigations, 63R; Diseases
of the Citrus Aphid, 64R; Coconut Bud Rot, 67R; Citrus Blight,
Water Injury, etc., 68R; Pecan Disease Work, 70R; Potato Dis-
ease Work, 70R; Truck Crop Diseases, 73R; Strawberry Investi-
gations, 75R.
REPORT OF THE VETERINARIAN .....-....---.....................--.....---..----....... 78R
"Salt Sickness," 78R; Manson's Eye Worm of Poultry, 79R;
"Leeches" in Horses, 81R; Kidney Worm of Swine, 81R; Diag-
nostic Work, 82R
REPORT OF AGRICULTURAL ECONOMIST ....--............----- ----------------------- 84R
Hastings Irish Potato Area, 84R; Costs of Picking, Hauling and
Packing Citrus, 84R; Jackson County Survey, 85R; Costs of
Transportation of Florida Citrus, 85R.
REPORT OF THE LIBRARIAN ............... ..-..... ........... -------- 87R
REPORT OF HOME ECONOMIST .................-....-- .......---- ... ..---------------- 89R
Vitamin A, 89R; Nutritional Survey, 90R; Some Factors That
Influence Jellying, 91R; Canning of Non-Acid Vegetables, 91R.
REPORT OF CITRUS EXPERIMENT STATION ........-.......-----------------------... 92R
Buildings and Improvements, 92R; Dieback Grove, 93R; Potash
Groves, 93R; Pathological Grove, 94R; Controlling June Bloom
by Irrigation, 95R; Cultural Experiments, 95R; Agronomy Ex-
periments, 96R.
REPORT OF TOBACCO EXPERIMENT STATION .................-------------------- 98R
Disease Investigations, 98R.
REPORT OF EVERGLADES EXPERIMENT STATION ...........------------------.... ...- 104R
General Plan of the Station, 104R; Storm and Flood Damage,
106R; Buildings and Improvements, 107R; Meterological Rec-
ords, 109R; Drainage Record and Ground Water Movement,
114R; Investigational Work, 117R.





















Hon. John W. Martin,
Governor of Florida,
Tallahassee, Florida.
SIR: I have the honor to transmit herewith the annual re-
port of the Director of the University of Florida Agricultural
Experiment Station for the fiscal year ending June 30, 1927.
Respectfully,
P. K. YONGE,
Chairman, Board of Control.







BOARD OF CONTROL
P. K. YONGE, Chairman, Pensacola E. L. WARTMANN, Citra
E. W. LANE, Jacksonville J. T. DIAMOND, Secretary, Talla-
A. H. BLANDING, Leesburg hassee.
W. B. DAVIS, Perry J. G. KELLUM, Auditor, Tallahassee
STATION EXECUTIVE STAFF
WILMON NEWELL, D. Sc., Director ERNEST G. MOORE, M. S., Asst. Ed
JOHN M. SCOTT, B. S., Vice-Director IDA KEELING CRESAP, Librarian
S. T. FLEMING, A. B., Asst. to Di- RUBY NEWHALL, Secretary
rector K. H. GRAHAM, Business Manager
J. FRANCIS COOPER, B. S. A., Editor RACHEL MCQUARRIE, Accountant
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.
A. S. LAIRD, M. S. A., Asst.
ANIMAL INDUSTRY
JOHN M. SCOTT, B. S., Animal
Industrialist
F. X. BRENNEIS, B. S. A., Dairy
Herdsman
CHEMISTRY
R. W. RUPRECHT, Ph.D., Chemist
R. M. BARNETTE, Ph. D., Asst.
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.


BRUCE MCKINLEY, B. S. A., Asst.
M. A. BROKER, M. S. A., Asst.
ECONOMICS, HOME
OUIDA 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., Asso. Hort.
M. R. ENSIGN, M. S., Asst.
HAROLD MOWRY, Asst.
G. H. BLACKMON, M. S. A., Pecan
Culturist
PLANT PATHOLOGY
G. F. WEBER, Ph. D., Asso.
K. W. LOUCKS, B. S., Asst.
ERDMAN WEST, B. S., Mycologist


E. F. GROSSMAN, M. A., Asst. VETERINARY MEDICINE
RAYMOND CROWN, B.S.A., Field Asst. A. L. SHEALY, D.V.M., Veterinarian
ECONOMICS, AGRICULTURAL D. A. SANDERS, D. V. M., Asst.
C. V. NOBLE, Ph. D., Ag. Economist E. F. THOMAS, D. V. M., Lab. Asst.
BRANCH STATION AND FIELD WORKERS
W. B. TISDALE, Ph. D., Plant Pathologist, in charge, Tobacco Experiment
Station (Quincy)
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)
R. L. MILLER, Assistant Entomologist (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)
J. H. HUNTER, M. S., Assistant Agronomist (Belle Glade)
J. L. SEAL, Ph. D., Assistant Plant Pathologist (Belle Glade)
H. E. HAMMAR, M. S., Field Assistant (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)
E. D. BALL, Ph. D., Associate Entomologist (Sanford)

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














Report for the Fiscal Year Ending

June 30, 1927



Hon. P. K. Yonge,
Chairman, Board of Control.
SIR: I have the honor to transmit herewith my report on the
work and investigations of the University of Florida Agricultu-
ral Experiment Stations, together with the reports of the heads
of the several departments, for the fiscal year ending June 30,
1927; and I request that you transmit the same, in accordance
with law, to His Excellency, the Governor of Florida.
Respectfully,
WILMON NEWELL,
Director.

INTRODUCTION
A summary of the activities of the various departments in the
Experiment Station and its Branch Stations and Field Labora-
tories is given in the following pages.
The fiscal year just closed has been the second year of the
biennium and the resources have been practically the same as
during the preceding year. The financial resources of the Ex-
periment Stations for the fiscal year ending June 30, 1927, have
been as follows:

Adams Fund ..................-.........- $ 15,000.00
Hatch Fund ...---------. 15,000.00
Main Station, Gainesville ........... .. ..... ...... 162,506.75
Citrus Station .--...------------. 20,689.03
Tobacco Station .... ................................. 18,627.18
Everglades Station ....- ...- .. .............. 56,992.56
Special Appropriation, Labor .............. .............. .. 8,634.88
Station Incidental Fund ................ .. --...- ........ 12,167.18
Total ........... .......... ..... ......- $309,617.58
Purnell Fund, not included above....- .................._-. 30,000.00






Florida Agricultural Experiment Station


CHANGES IN STAFF
Dr. R. V. Allison was appointed Soils Specialist, Everglades
Experiment Station, September 1, 1926.
O. M. Berg was appointed Assistant Chemist October 27, 1926
and resigned November 9, 1926.
Dr. E. D. Ball was appointed Associate Entomologist with
headquarters at Sanford, effective July 1, 1926.
H. E. Bratley, Laboratory Assistant in Entomology, was
granted leave of absence from October 15, 1926 for one year.
M. A. Brooker was appointed Assistant in Agricultural Eco-
nomics July 1, 1926 to September 15, 1926 and again appointed
effective May 1, 1927.
Paul Calhoun was appointed Student Assistant, Cotton Inves-
tigations, effective September 15, 1926.
Dr. A. F. Camp was transferred from the position of Plant
Physiologist in charge of Cotton Investigations to the position
of Associate Horticulturist, effective July 1, 1926.
E. W. Cowan, Assistant Chemist, resigned September 15,
1926.
M. R. Ensign was appointed Assistant Horticulturist October
1, 1926.
Dr. L. W. Gaddum was appointed Assistant in Home Econom-
ics Research, September 29, 1926.
H. G. Hamilton, Assistant Agricultural Economist, was grant-
ed leave of absence for one year from September 30, 1926.
J. B. Hester was appointed Assistant Chemist effective Jan-
uary 1, 1927.
J. G. Kelley, Laboratory Assistant, Tobacco Experiment Sta-
tion, was transferred to the Everglades Experiment Station as
Field Assistant, effective November 1, 1926.
H. L. Marshall was appointed Assistant Chemist January 24,
1927.
R. L. Miller was appointed Assistant Entomologist, with head-
quarters at the Citrus Branch Station, May 1, 1927.
Q. E. Patton, Greenhouse foreman, resigned June 30, 1927.
Pence Peterson, dairy foreman, resigned January 17, 1927.
F. X. Brenneis was appointed dairy foreman January 17, 1927.






Annual Report, 1927


C. H. Taylor, Student Assistant, Horticultural Test Grounds,
resigned April 30, 1927.
Mrs. Lucy Tedder, Housekeeper, Everglades Experiment Sta-
tion, resigned May 31, 1927.
Mrs. Bertha Lockmiller was appointed Housekeeper, Ever-
glades Experiment Station, June 1, 1927.
W. L. Thompson was appointed Assistant Entomologist, with
headquarters at the Citrus Branch Station, March 7, 1927.
Ross F. Wadkins was appointed Field Assistant, Everglades
Experiment Station, July 15, 1926 and transferred to the To-
bacco Experiment Station as Laboratory Assistant, November
1, 1926.
F. W. Walker was appointed Assistant Entomologist with
headquarters at Monticello, February 1, 1927.
Dr. M. N. Walker was appointed Assistant Cotton Specialist
December 1, 1926.
Miss Georgia Westover, Assistant in Home Economics Re-
search, resigned September 1, 1926.

SCOPE OF THE STATION WORK, JULY 1, 1926 TO JUNE
30, 1927
A list of the principal active projects carried on during the
year is given below, arranged according to departments.









Department
AGRONOMY
(see page 17R)







ANIMAL INDUSTRY
(see page 27R)


CHEMISTRY
(see page 33R)


Name of Project
Introduction and trial of forage plants, including variety test work with general
farm crops.
Plant breeding; peanuts and Napier grass.
Rotation and fertilizer experiments with corn, sweet potatoes, peanuts, Napier
grass and other crops.
Pasture and lawn grass studies.
Cover crop and green manure studies.
Winter legume studies.
Crop rotation studies with velvet beans, corn, sweet potatoes and peanuts.
Improvement of corn through selection and breeding. (New project.)
A comparison of home-grown and purchased feedstuffs for economical milk produc-
tion.
Comparison of home-grown and purchased feedstuffs for economical pork produc-
tion.
Soil and nutrition studies with reference to dieback of citrus.
Determination of the effect of varying amounts of potash on the composition of
oranges and grapefruit.
Determination of the fertilizer requirements of Satsuma oranges.
Determination of the effect of various potash carriers on the growth of citrus trees
and composition of the fruit.
Determination of fertilizer requirements of blueberry.
Effect of various fertilizer treatments and of soil amendments on prevalence of
nailhead rust in tomatoes.
Determination of the mineral constituents of various Florida-grown cattle feeds,
as compared with feeds grown farther north.
Determination of the effect of various carriers of potash on growth and quality of
shade tobacco.
Determination of the effect of various carriers of phosphoric acid on the growth
and quality of shade tobacco.
Determination of the need for manure in growing shade tobacco.
Composition of crops as influenced by fertilization and soil types.
Determination of the effect of green manures on composition of soil. (New pro-
ject.)
Determination of the cause of poor crop growth due to liming sandy soils. (New
project.)


Project No.
XIII-A

XIII-B
XIII-C

XIII-D
XIII-E
XIII-F
XIII-G
XXVIII
XI-C

XII-B


V
IX-B

IX-C
IX-D

IX-E
IX-F

XV-A

XVIII-A

XVIII-B

XVIII-C
XX
XXX

XXXI




Department Name of Project Project No.


COTTON INVESTI-
GATIONS
(see page 38R)



ENTOMOLOGY
(see page 44R)


HORTICULTURE
(see page 51R)


Cotton diseases; wilt, seedling diseases, rust or mosaic of cotton.
Cotton physiology; cotton rust, cotton nutrition.
Genetics of cotton; variety testing and breeding; studies in the inheritance of cot-
ton.
Control of cotton insects; the boll weevil.
Field tests with cotton. Spacing and time of planting tests.
The green citrus aphid (Aphis spiraecola).
Florida flower thrips on citrus.
Florida flower thrips on peanuts, beans, eggplants and forage crops.
Control of root-knot.
Study of plant bugs attacking citrus, pecans and truck crops.
Velvet bean caterpillar (Anticarsia gemmatilis).
Further study of the bean jassid (Empoasca fabae).
Introduction and study of beneficial insects.
Insects affecting pecan trees.
Life history studies of Pycnoscelus surinamensis L., the roach which is the inter-
mediate host of Manson's eye worm (Oxyspirura mansoni): including a study
of its natural enemies and methods of control. (New project.)
Propagation, planting and fertilizing tests with tung-oil trees.
Testing of native and introduced shrubs and ornamentals and methods for their
propagation.
Observation and testing of various citrus hybrids.
Variety tests of grapes.
Tests of different stocks as rootstocks for the Satsuma orange.
Variety tests of berries-Rubus sp.
Variety, propagation and planting tests of pear, avocado, Japanese persimmon,
fig and other fruits.
Phenological studies on truck crops in Florida. (New project.)
Fundamental physiology of fruit production. (New project.)
Compilation of available information upon the varieties of pecans best suited to
different localities and soil types in Florida and collecting information as to
the best proven methods of fertilizing, propagating and growing pecans.
Variety and stock tests of pecans and walnut trees at the Gainesville station.
Cooperative fertilizer tests in pecan orchards.
Field study of the insects attacking the pecan, including control measures.


XXI-A
XXI-B
XXI-C

XXI-D
XXI-E
III Major A
III Major B 1
III Major B 2
III Major C
III Major D
III Minor A 1
III Minor B
VIII-A
XVII-A
XXXIII


XIV-A
XIV-B

XIV-C
XIV-D
XIV-E
XIV-F
XIV-G

XXIX
XXXII
XIX-A

XIX-B
XIX-C
XIX-D









Department Name of Project
Field study of the diseases attacking the pecan, including control measures.
Cooperative cover crop tests in pecan orchards.
PLANT PATHOLOGY Citrus diseases; gumming (in cooperation with State Plant Board).
(see page 63R) Citrus diseases; melanose and stem-end rot.
Citrus canker; study of the organism; inoculation of hosts (in cooperation with
State Plant Board).
The downy mildew or cucurbits.
Diseases affecting the twigs, branches and stems of pecan trees.


Project No.
XIX-E
XIX-F

II Major A 1
II Major A 2
II Major A 3

II Major B 1
II Major C 1


Anthracnose of citrus fruits (inactive during year). II Minor A 1
Fruit spotting of avocados (inactive during year). II Minor B 1
Avocado scab (inactive during year). II Minor B 2
Phomopsis of eggplant. II Minor C 1
Bacterial blight of Solanaceae and bacterial blight of cucumber and other vege- II Minor C 2
tables.
Bacterial disease of cucumber, known as "angular leaf spot"; the disease of pep- II Minor C 3
pers known as "blisters."
Seedbed diseases of lettuce, celery, eggplant and tomato (in cooperation with Bu- II Minor C 4
reau of Plant Industry, U. S. D. A.).
Citrus scab; spraying experiments to determine the proper time for spraying, and VII-A 1
the best sprays for the control of the disease.
Citrus canker; Length of life of the organism in the soil and on old hosts; meth- VII-A 2
ods of distribution; control methods.
Citrus blight; distribution, cause and control. XVI-B 1
Control of downy mildew on cucurbits and other host plants. VII-B 1
Potato diseases, including potato wilt and late blight. XVI-A 1
Entomogenous fungi; diseases of citrus aphids. (New project.) XVI-C 1
Strawberry diseases; distribution, cause and control. (New project.) XVI-D


VETERINARY
(see page 79R)


"Salt sickness" in cattle.
Manson's eye worm of poultry (Oxyspirura mansoni).
Use of chlorine gas in treatment of infectious mastitis in cattle.
"Leeches" of horses.
Types of hemorrhagic septicemia found in Florida.
Kidney worms (Stephanurus dentatus) in swine. (New project.)


XXII-A
XXII-B
XXII-C
XXII-D
XXII-E
XXII-F





Department Name of Project Project No.


AGRICULTURAL
ECONOMICS
(see page 85R)


HOME ECONOMICS
(see page 90R)






CITRUS BRANCH
STATION
(see page 93R)




TOBACCO BRANCH
STATION
(see page 99R)
EVERGLADES
BRANCH STATION
(see page 105R)


An economic study of 300 or more potato farms in the Hastings area. XXVI-A
A study to determine the cost of picking, hauling and packing of Florida citrus XXVI-B
fruits, to be made in approximately 100 packinghouses operated by both mar-
keting associations and private organizations.
An agricultural survey of some 500 farms in the general farming region of XXVI-C
Northwest Florida.
A study of the cost of transportation of Florida citrus fruits with comparative XXVI-D
costs from other states and foreign countries. (New project.)
Determination of whether chlorophyll, chlorophyll alpha and beta, the petroleum- XXVII N
ether extracts of the yellow pigments of alfalfa, can be used as a source of vita-
min A in animal nutrition.
A study to determine the apparent prevalence of nutritional diseases in rural school XXVII R
children between the ages of six and twelve years in five representative coun-
ties of Florida.
Determination and identification of the organisms which cause the spoilage of can- XXVII 1
ned vegetables in the South.
Study of the factors affecting the jellying of kumquats, loquats, roselle and guava. XXVII D
Testing of introduced and new varieties and hybrids of citrus and near-citrus (in XXIII-A
cooperation with Bureau of Plant Industry, U. S. Dept. of Agriculture).
Variety tests of various citrus varieties on different rootstocks. XXIII-B
Progeny and bud selection investigations (in cooperation with Bureau of Plant XXIII-C
Industry, U. S. Dept. of Agriculture).
Propagation experiments with various citrus plants. XXIII-D
Cover crop and green manure studies in citrus groves. .XXIII-E


Field and laboratory studies of tobacco diseases.
Fertilizer experiments with shade-grown tobacco.
Variety tests of tobacco and other crors.
Forage, truck and field crop trials.
Fruit and forest tree trials.
Field fertilizer experiments.
Drainage studies.
Soil investigations.
Insect pests and plant diseases and their control.
Soil and crop studies, including rotation, fertilizer and cultural practice experi-
ments.


lajor A


lajor B

Iiner A

Minor B


XXIV-A
XXIV-B
XXIV-C
XXV-A
XXV-B
XXV-C
XXV-D
XXV-E
XXV-F
XXV-G






12R Florida Agricultural Experiment Station







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, 1927.
Respectfully,
K. H. GRAHAM,
Business Manager.

MAIN EXPERIMENT STATION, 1926-1927
RECEIPTS
Balance, 1925-1926 ----............. -- ...............-....-.... $ 3,502.44
State Appropriation, % Biennium .............................. 159,004.31

$162,506.75
EXPENDITURES
Salaries ............................................... ......................$ 79,856.81
Labor ........- ----......................................... .. 14,771.35
Stationery and Office Supplies ...................................... 2,491.54
Scientific supplies .... .......... ................................ 3,322.91
Feeding stuffs ............................................................. 3,177.50
Sundry supplies .......... ................................ ....... 4,288.34
Fertilizers ---- ---........... ------... ........................- 2,822.50
Communication service .............-- ............ ............. 1,357.73
Travel --------............................................ 12,387.93
Transportation of things .- -....................................... 1,293.49
Publications ...................................................... 5,663.04
Heat, light, water, power -.....................-................. 1,842.72
Furniture, furnishings, fixtures .................................... 12,020.74
Library ............. ...................... ........................ 3,613.11
Scientific equipment ............... -....................................... 3,984.58
Livestock 61.00
Livestock ........................................................................ 61.00
Tools, machinery ..................... ........................... 2,486.47
Buildings and land --..........................-.......... ...... 6,565.90
Contingent .................................................................. ... 499,09

$162,506.75






Annual Report, 1927 13R

SPECIAL APPROPRIATION MAIN STATION, 1926-1927
RECEIPTS
Balance, 1925-1926 .................................................. 8,634.88

EXPENDITURES
Labor ................................ .......... ........$ 8,634.88

STATION INCIDENTAL FUND, 1926-1927
Balance, 1925-1926 ................................ ..................$ 2,165.38
Receipts, 1926-1927 ....................... ...... ... ...... .... 10,001.80

$12,167.18
EXPENDITURES
Salaries .................. .............. ................ ....$ 200.00
Labor ........................................ ....... .. ...................... 531.10
Scientific supplies ..................... ................ 99.48
Feeding stuffs ...................... ..... ........... 5,245.06
Sundry supplies ........................................... .................. 338.82
Fertilizers .............................................. 356.98
Travel .................................... ............ 13.72
Transportation of things ........................................ 146.04
Heat, water, light, power ........................................... 143.43
Furniture, furnishing, fixtures ....--......................-......... 120.00
Library ........................................................................... 19.25
Scientific equipment ....-----........................-- ..... ........ 142.60
Livestock ...................... .................... ......... ................. 278.75
Tools, m achinery ........................................... ............ 254.99
Buildings and lands .....-........................... ......-- ......- -. 920.39
Contingent ......................... .. ................... ............. 19.01
B balance ......................................................... 3,337.56

$12,167.18

CITRUS EXPERIMENT STATION FUND, 1926-1927
RECEIPTS
Balance, 1925-1926 ........................-- -..........................$ 6,114.03
State appropriation, 1926-1927 ...-................................ 14,575.00

$20,689.03
EXPENDITURES
Salaries ..................... ............................................- $ 2,600.00
L abor ....................................................... .. .................... 2,274.37
Stationery and office supplies ................:.......-............. 4.50
Scientific supplies ........................... ........-- --......... 7.00
Feeding stuffs ................. ...... .......... ............ 405.14
Sundry supplies --.........-........ ..... ..........-........ 341.30
Fertilizers .................................................. ........-........-...... 238.48
Communication service ..-.....-.....-................----... ---.. 38.19
Travel .......----------..................-..............--....----.....-. 152.30
Transportation of things .....-..........---- ......................... 138.66
Heat, light, water, power ........................................ 181.44
Furniture, furnishing, fixtures .................................. 20.00
Library ...--- ........-....--.. --.....-....-........ ................... 5.25
Scientific equipm ent ......................................... .-- ..-- .. 12.69
Tools, m achinery .................. ....................................... 870.97
Buildings and lands ................................... .................. 13,391.74
Contingent ....................................................... .......... 7.00

$20,689.03






14R


Florida Agricultural Experiment Station



TOBACCO EXPERIMENT STATION FUND, 1926-1927
RECEIPTS


B balance ...... .....-.. ....- ....-.....
State appropriation, 1926-1927


EXPENDITURES
Salaries .......... .... ....--... ----. ....
L abor ........... ................. .. ..... ....-
Stationery and office supplies ..................
Scientific supplies ...................................
Feeding stuffs ...........-- ..-- ..........
Sundry supplies ...-................-...............-
Fertilizers -.. ....... --.. .. .....--
Communication service .-- ..-..------
T ravel ...... .... ... ...-..- .....- ... .. .. .
Transportation of things .............................
Heat, light, power ......-... .......................
Furniture, furnishings, fixtures ......... ....
Library ............. ..... ..- ...... .. -- .... ..
Scientific equipment --..-.. ...-.. .
Tools, machinery .... --- -..... ....
Buildings and lands ...-
Contingent ..- ....- .. ..-- :. ... .-


......... $ 7,291.67
.-....-.- 2,041.49
.-..- 19.73
... 99.78
.. 92.46
... 336.61
... 585.50
......... 59.27
.. 403.89
-.....- 19.72
... 185.88
.. 40.50
S......... 124.60
.. 160.55
... 679.58
....... 6,449.95
.-.... .. 36.00


EVERGLADES EXPERIMENT STATION FUND, 1926-1927
RECEIPTS


B balance ........ ...... ......-.. ...
State appropriation, 1926-1927


.$ 6,992.56
S50,000.00


$56,992.56


EXPENDITURES


Salaries ........-- .... ..... -- ----. -
L abor ....... ............ -...............
Stationery and office supplies
Scientific supplies -.......... ---
Feeding stuffs ........................-...-
Sundry supplies ............. .- ....--
Fertilizers .:......... ..... .. --.. --
Communication service -........-
Travel ........... ...- .... .... ... ..-
Transportation of things ..........
Heat, light, power ................ --.......
Furniture, furnishings, fixtures ....
Library .-. ............... -- .....-
Scientific equipment .............-
Tools, machinery ........-- ...--...
Buildings and lands -...-------.... -------..
Contingent ................. .. ...... .....
Balance .....-- -----.. ...


- ......- ..-.- .... ... 11,378.34
-.-..-..- .- ....- 10,443.83
.--. -.-..- .- ..- 166.72
..-.- ....-.- .... 1,897.93
.-.-..-. -- 141.40
....---.- 1,957.38
-.-... ..- ..- .. 21.50
.-. .. .. 127.08
..;- .-- 508.98
--....--.--- 874.53
.-.- ....-.-- ..- 1,939.47
.-. -. ..-- ..-. ... 821.98
.-- ... ..-.. 247.63
-.. -.. -... 2,900.70
.. ... .. .... ... 1,822.66
........-... ......... 14,393.78
.. ...... ... 357.37
...- ...... 6,990.98


$56,992.56


.$ 3,627.18
15,000.00


$18,627.18



















$18,627.18





Annual Report, 1927


PUBLICATIONS

Wilmon Newell, Director.
SIR: I submit the following report of the Editorial Depart-
ment for the fiscal year ending June 30, 1927.
Respectfully,
J. FRANCIS COOPER,
Editor.

Following is a list of the publications issued by the Experi-
ment Station during the fiscal year ending June 30, 1927.
BULLETINS
No. Title Pages Edition
184 Palms of Florida ............. ....... ..... ......... .... 56 8,000
185 Diseases of Tomatoes in Florida ......................... 84 15,000
186 Thread Blight ......................... .......... ..... .......... 24 2,500
187 Infection of Potato Tubers by Alternaria Solani.. 18 5,000
188 Ornamental Vines ..... ...... ... .... ..- ........ 48 15,000
173 Celery Diseases in Florida (reprint) .................... 56 5,000
A Method for Taking a Farm Inventory.. .......-... 20 5,000
A Method for Keeping a Cash Account on a Farm 64 5,000

SUMMARY OF BULLETINS

No. 184, Palms of Florida. (Harold Mowry), pp. 56, Figs.
57. Description of the various species of palms of Florida, giv-
ing their common names, degree of hardiness, place of origin,
and part of the state to which the species is most adapted. Bulle-
tin contains suggestions on propagation, planting, and fertiliz-
ing. Also map of Florida divided into three zones, adapted to
tender, semi-hardy and hardy plants.
No. 185, Tomato Diseases in Florida. (G. F. Weber), pp. 84,
Figs. 42. Discusses the importance of diseases in the growing
and marketing of tomatoes. Describes each disease, giving symp-
toms and control measures. Treats of sanitation and rotation,
seedbed sterilization and seed disinfection, fungicides and their
application.
No. 186, Thread Blight, a Fungous Disease of Plants Caused
by Corticium Stevensii Burt. (G. F. Weber), pp. 24, Figs. 9.
Reports the geographical distribution, host range, economic
importance, and symptoms of the disease. Gives the taxonomy,
morphology, physiology, and pathogenicity of the causal or-
ganism. Discusses the seasonal development, source of inoculum,
longevity, overwintering, and control of the causal organism in
relation to the production of the disease.





Florida Agricultural Experiment Station


No. 187, Infection of Potato Tubers by Alternaria Solani in
Relation to Storage Conditions. (L. O. Gratz and Reiner Bonde),
pp. 18, Figs. 9. Alternaria solani, the cause of "early blight" of
potatoes, was formerly considered nonparasitic on tubers. Re-
cent observations, however, have shown it to be parasitic on
tubers. Bulletin discusses tuber symptoms, losses, early observa-
tions, miscellaneous observations, experimental work, and con-
clusions.
No. 188, Ornamental Vines. (Harold Mowry), pp. 48, Figs.
51. Takes up the use of ornamental vines in beautification. Dis-
cusses propagation, trellising, fertilizing, pruning, and climatic
adaptation of vines. Describes the different species of vines,
stating their degree of hardiness, point of origin, principal uses,
and method of propagation. Contains a simple key to the vines.

PRESS BULLETINS
No. Title Author
390 Treating Seedbeds for Root-knot Nematodes.-..................J. R. Watson
391 "Salamanders" and "Gophers" .........--..... ----... --............ J. R. Watson
392 Control of Mealy Bugs.-..-...-...----------..................................... J. R. W atson
393 Treatment of Frost-Injured Citrus Trees .................E. F. DeBusk and
A. F. Camp
394 Bulbs .......-....--.. -----........--......-..--- .....--Harold Mowry
395 Manson's Eye Worm in Poultry...-----.................... Dr. D. A. Sanders
396 Blackberries and Dewberries ... .....----...------..... Harold Mowry
397 Asparagus as a Truck Crop in Florida.......---------.....M. R. Ensign
398 Crotalaria as a Soil Builder--.......--.......W. E. Stokes and W. A. Leukel
399 Growing Annual Flowering Plants .-...........----------....W. L. Floyd
400 Preparation of Bordeaux Mixture-----...........--..... G. F. Weber
Bulletin List
277 Bud-Worm or Corn-Ear-Worm (reprint) ....................-----....J. R. Watson
283 Pumpkin Bugs in Citrus Groves (reprint)...... ....-------.J. R. Watson
326 Spraying for Citrus Whitefly (reprint).......---.....----.. J. R. Watson
333 Poisoning Grasshoppers (reprint) .--.....................------...........--J. R. Watson
338 Use Sulphur for Red Spiders (reprint)---------..........................J. R. Watson
344 Cottony Cushion Scale (reprint) ......-------............................ J. R. Watson
348 Growing Sweet Peas in Florida (reprint) -----...........................W. L. Floyd
364 Varieties of Pecans for Florida (reprint)......................G. H. Blackmon
384 Asparagus Plumosus (reprint) ........................--- -----...............Harold Mowry
389 Lawns in Florida (reprint) ................------..................... --W. E. Stokes


16R





Annual Report, 1927


REPORT OF AGRONOMIST
Wilmon Newell, Director.
SIR: I submit the following report for the Department of
Agronomy for the fiscal year ending June 30, 1927.
Respectfully,
W. E. STOKES,
Agronomist.

The lawn, pasture, and forage crop investigational work of
the department has been carried on in cooperation with the
Office of Forage Crops Investigations of the Bureau of Plant
Industry of the United States Department of Agriculture. The
Chemistry Department of the Experiment Station has cooper-
ated in the lawn grass, green manure, and forage crop studies.

NEW PROJECTS
One new project dealing with corn breeding has been sub-
mitted to and approved by the Station Project Committee, and
when approved by the proper officials of the United States De-
partment of Agriculture, will be carried on as a Purnell project.

PROGRESS OF THE YEAR'S WORK
During the year seed and vegetative material of 22 grasses
and 174 legumes were received from the Office of Forage Crops
Investigations of the Bureau of Plant Industry of the United
States Department of Agriculture for trial. All of this material
was planted in either greenhouse, grass garden, or plot field
for study. No new plant under observation during the year has
been found superior to new ones reported heretofore.

VARIETY TESTS
During the year variety test work was carried on with the
following crops: Corn, sorghum, oats, peanuts, and soybeans.
During the coming year it is planned to publish in detail the
results of all variety tests to date.

WINTER LEGUMINOUS PLANTS
Much emphasis has been put on the study of winter legumi-
nous plants, both on the Experiment Station grounds and on co-


17R





Florida Agricultural Experiment Station


operative experimental fields in Duval, Bradford, and Jackson
counties. The following legumes were inoculated and planted on
Norfolk sandy soil at the Experiment Station: hairy vetch (Vicia
villosa), Monantha vetch (Vicia monantha), Red clover (Trifo-
lium pratense), biennial white sweet clover (Melilotus alba),
Hubam clover (Melilotus alba var. Hubam), annual yellow
sweet clover (Melilotus indica), Alsike clover (Trifolium hybri-
dum), bur clover (Medicago maculata), Kansas alfalfa (Medi-
cago sativa), and Serradella (Ornothopus sativus).
The hairy and Monantha vetches made the most satisfactory
growth of any of the leguminous plants mentioned and made it
early enough so that the land could be prepared and planted to
other crops on time. Monantha vetch did not make as much to-
tal yield as hairy vetch, but made more yield earlier in the sea-
son. Neither of the vetches made a satisfactory seed crop.
Alfalfa, bur clover, sweet clover, red clover, and alsike clover
failed to make a satisfactory growth on Norfolk sandy soil.
Alfalfa, bur clover, hairy vetch, and biennial white sweet
clover planted in the fall on highly fertilized Norfolk sandy soil
made a satisfactory growth. Annual yellow sweet clover did not.
Where these crops were irrigated under the above conditions, the
yields of alfalfa, bur clover, and biennial white sweet clover
were increased. It is doubtful, however, whether irrigation and
high fertilization for these crops in Florida is a practical and
economical thing to recommend.
In the cooperative experiments, hairy vetch gave more promise
as a leguminous winter cover crop than any other plant. Espe-
cially was this true where acid phosphate was used at the rate
of 300 to 500 pounds per acre previous to planting inoculated
seed in the fall. Hairy vetch did exceptionally well on the fol-
lowing soils: Bladen fine sandy loam, Coxville sandy loam,
Norfolk fine sand, Norfolk sandy loam, Orangeburg sandy loam,
and Greenville sandy loam. On dry sandy soils lack of moisture
and presence of root-knot nematodes seemed largely to prevent
satisfactory growth.
Hubam clover, annual yellow sweet clover, and bur clover
made a fair growth on all soils mentioned above except the Nor-
folk fine sand.


18R






Annual Report, 1927


CROTALARIA
A number of new species of Crotalaria were under observa-
tion during the year. None seemed more promising than Crota-
laria striata and Crotalaria sericea. On Norfolk sandy soil Crota-
laria striata continued to yield higher, in tons of hay, than cow-
peas, beggarweed, or velvet beans.


Fig. 1.-Crotalaria striata. The upper plant was grown on Leon soil under-
laid with a hardpan. The lower plant, having roots 9 feet 6 inches long
was grown on Norfolk sand.


19R





Florida Agricultural Experiment Station


A preliminary I'
study of the root a..
system of Crota-
laria striata, Cro-
talaria sericea,
and Crotalaria in-
cana showed that
on Norfolk sandy -
s o il I Crotalaria
striata roots grew ]
very deeply. Ex-
treme depths of
roots found Was .0
nine feet and six
inches s, almost
straight do w n.
On flatwood soil
underlaid with
hardpan the root
system was com-
paratively shal-
low, going down
until the hardpan
was reached and
t hen spreading
laterally. Roots
were well nod-
uled, apparently
being better nod-
uled on the more
moist soil.
Several thou-
sand pounds of
hay were saved
from Crotalaria
striata of a full Fig. 2.-Roots of Crotalaria striata grown in pots
season's growth. in the greenhouse.
The hay was cut the first week in November. Approximately
3,000 pounds of meal was made by grinding a part of the Crota-
laria hay. This meal is being fed to dairy cattle in comparison
with alfalfa meal. For details of the experiment see the report
of the Animal Industrialist.


20R






Annual Report, 1927


Press bulletin 398 on Crotalaria as a Soil Builder, was publish-
ed during the year.
PLANT BREEDING
The breeding work with Spanish peanuts was continued. Some
seed of high yielding strains will be available for distribution
during the spring of 1928.
FERTILIZER EXPERIMENTS
The fertilizer work with Spanish peanuts in a rotation with
corn and velvet beans on Norfolk sand was continued. Ground
limestone continues to decrease the yield of peanuts, corn, and
velvet beans, although no limestone has been applied in this ex-
periment since 1922. Acid phosphate, hard phosphate, soft phos-
phate, potash, and nitrogen alone, and acid phosphate, hard
phosphate, and soft phosphate each in combination with nitro-
gen have in no case increased peanut yield materially. As men-
tioned in the previous annual report, controlled greenhouse pot
work is being done by the Department of Chemistry to deter-
mine the cause for the detrimental results from the use of
ground limestone.

SYSTEMATIC SPANISH PEANUT FERTILIZER
EXPERIMENT
The peanut fertilizer experiment was continued and, as here-
tofore reported, no paying increase in yield with land plaster
alone was obtained. No fertilizer treatment has materially in-
creased yields, though some treatments this year gave slight in-
creases. The experiment has been enlarged, starting with the
1928 crop, to give information on the effect of varying amounts
of complete fertilizers and varying formulas on Spanish peanut
yields. It is planned to report in bulletin form the results of this
experiment as soon as possible after the end of the 1927 grow-
ing season.
CROP ROTATION STUDIES
A six-phase, three-year crop rotation experiment started in
1924 was continued. This experiment has run through one com-
plete three-year cycle and is now being started over and should
begin to show, in a few more years, some interesting results. The
experiment is planned to show (1) the effect of continuous
cropping to corn, peanuts, and sweet potatoes respectively; (2)


21R





Florida Agricultural Experiment Station


the value of a three-year rotation of corn and velvet beans, fol-
lowed by peanuts followed by sweet potatoes; (3) the value of
the legume in the corn versus no legume; (4) the value of the
rotation with and without fertilizer; (5) the value of a winter
cover crop of oats in the rotation; and (6) the effect of varying
the amount of complete fertilizer on the crops in the rotation.

LAWN GRASS STUDIES
The work with lawn grasses was continued along much the
same line as last year.
Centipede grass (Eremochloa ophiuroides) and St. Augustine
grass (Stenotaphrum secundatum) continue to be the two out-
standing lawn grasses, with Bermuda grass (Capriola dacty-
lon) and carpet grass (Axonopus compressus) showing up well.
For the past two years we have been able to keep Bermuda
grass lawns and golf course putting-greens green throughout the
year by watering as needed, applying sulfate of ammonia or
ammonium phosphate every two weeks (total per acre per year
application being 1,000 pounds) and mowing daily during the
summer and about three times a week during the winter months.
Under these conditions it was not necessary to sow any winter
grass for greening up purposes.
No checking of weed growth has yet been had from two years
use of sulfate of ammonia and ammonium phosphate compared
to nitrate of soda plots. The report of the Department of Chem-
istry gives the pH- value of soil from lawn and golf course grass
fertilized plots.
The preliminary study of the root systems of sod-forming
grasses was completed during the year and the results are now
ready for publication.

PASTURE GRASS STUDIES
Pasture experimental work has continued along the same
general lines as outlined in the previous annual report, except
that date-of-seeding tests have been completed and fertilizer ex-
perimental work has been enlarged. A small quantity of a com-
plete fertilizer continues to give good results when applied broad-
cast in the spring.
Dr. W. A. Leukel has handled the studies on growth and physi-
ological behavior of pasture grasses and the following is his
report on these studies:


22R






Annual Report, 1927


An outline of the studies on the growth and physiological be-
havior of sod-forming pasture grasses made during the year may
be found in the annual report of 1926. This work is being con-
ducted as outlined in the above report. Analytical work was
done on Bahia and carpet grasses from an established sod under
grazed and ungrazed conditions. Plants in the ungrazed areas
were found to be higher in percentage of easily hydrolyzable
carbohydrates and lower in total nitrogen, or showed a wider
carbohydrate-nitrogen relation as compared to those plants un-
der grazed conditions, which were somewhat lower in percentage
of easily hydrolyzable carbohydrates and slightly higher in total
nitrogen, showing a narrower carbohydrate-nitrogen relation.
Pasture plants not grazed seeded quite abundantly and produced
more of an upright growth, while those under grazed condi-
tions produced more vegetative top growth, fewer seed stems,
and were more prostrate in their growth habits, producing a
denser sod.
The work on transplanted Bahia grass as outlined in last
year's annual report has been progressing for the past three
months, but definite statements as to conclusions to be drawn
therefrom cannot be made at this time. Several outstanding
facts, however, are evident. The plants subjected to top-cuttings
at short intervals have produced thus far a much greater weight
of vegetative top-growth than the plants which were allowed to
grow to maturity. Plants subjected to cutting treatments are
spreading and producing more horizontal stems and forming a
dense sod. The plants receiving no cutting treatments are pro-
ducing more of an upright growth, seeding abundantly, and are
not producing much sod.
Analytical work thus far shows the plants in the cut area
to be higher in the soluble forms of nitrogen and showing a
narrower carbohydrate-nitrogen relation than those receiving
no cutting treatments. More detailed information will be avail-
able as the work progresses.

COVER CROP AND GREEN MANURE STUDIES
The cover crop and green manure studies have been contin-
ued with the enlargement noted in the previous annual report.
Crotalaria striata outyielded the other leguminous plants in
the tests at the Experiment Station at Gainesville and at the
Citrus Experiment Station, at Lake Alfred.


23R





Florida Agricultural Experiment Station


Sweet potato and corn yields were higher the year following
Crotalaria than following the other crops in the experiment.
The following is the report of Dr. W. A. Leukel, Associate
Agronomist, on the phase of this experiment which he has had
in charge:
Green manure studies with Crotalaria striata under green-
house conditions, in cooperation with the Department of Chem-
istry, as outlined in the last annual report, have progressed and
are being continued this year. The plants turned under in the
early succulent stages of growth were relatively high in percent-
ages of easily hydrolyzable carbohydrates and exceptionally
high in total nitrogen and the soluble forms of nitrogen. They
were relatively low in cellulose and lignin. After a period of
rapid vegetative growth there was a 50 percent decrease of easily
hydrolyzable carbohydrates and a marked increase in the per-
centage of cellulose and lignin, or the higher forms of carbohy-
drates. During the remainder of the growing season, or during
the period of flowering and seed formations, easily hydrolyz-
able carbohydrates again became normal in percentage. Lignin
remained rather constant in percentage during the remainder of
the growing season, while the cellulose showed a gradual in-
crease in percentage through the successive growth stages of
the plants. The percentage of total nitrogen in the tops and
roots of the plants was high during the early growth period, but
gradually decreased in percentage during the later growth
stages. The soluble forms of nitrogen followed a similar trend
in percentage. In quantity all compounds increased with the ad-
vance in plant growth and weight. The percentage of dry matter
in the plants increased as the plants approached the more ma-
ture growth stages.
A study of the relation of the various carbohydrates and nitro-
gen compounds in these plants at the various stages of growth is
being made. The effect on the ultimate nature and amount of
humus complex formed when they are incorporated in the soil,
is also being noted. The progress of these studies may be found
in the report of the Department of Chemistry.
These green manure studies are being continued this year
with transplanted Crotalaria plants grown under field condi-
tions; and with plants seeded and grown in lysimeters and in
field plots.


24R






Annual Report, 1927


The work concerning the proper height and stage of growth
for cutting Crotalaria so as to produce a vigorous after top-
growth, to produce seed for the next year's volunteer crop,
is being continued this year with transplanted Crotalaria plants
grown under field conditions. Plants seeded and grown in the
field last year were not uniform enough in their growth for in-
tensive study. A more detailed outline of this phase of work on
Crotalaria may be found in the annual report of 1926.

NAPIER GRASS STUDIES
Some detailed analytical determinations were made on the
crowns of Napier grass taken from field plots that were irri-
gated with sewage, field plots irrigated with city water, and
from plots receiving no irrigation as outlined in previous an-
nual reports. These plots received no sewage irrigation the past
two seasons, but increased yields of silage are still obtained from
the plots that were irrigated with sewage as compared to those
receiving no irrigation or irrigated with city water. On Febru-
ary 2, 1927, after the plants had produced a small amount of top
growth, definite areas of plants were dug from the different
plots and then prepared for analysis.
The green weights of the crowns, roots, and tops of the plants
dug from equal areas in the plots irrigated with sewage were
over twice as great as those from plants dug from similar areas
in plots not irrigated or irrigated with city water. A similar
comparison of dry weight of crowns and roots showed a three-
fold ratio in favor of the plants in the areas irrigated with sew-
age. The dry weight on the top growth on the plants in the irri-
gated area was approximately 33 percent greater in the sewage
irrigated area than the others.
On a percentage basis, the crowns of the plants in the sewage
irrigated area were higher in dry matter and all forms of easily
hydrolyzable carbohydrates and total nitrogen. Calculated on a
quantity basis from equal areas, the crowns of the plants irri-
gated with sewage contained five times as much ether extract,
twice the quantity of total sugar, soluble starch, and dextrins,
six times the quantity of starch, over three times the quantity
of hemicelluloses, three times the quantity of total hydrolyzable
carbohydrates and over four times the quantity of total nitro-
gen. No data are available as to the percentage and quantity
of these reserve organic foods in these plants at the time when


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26R


Florida Agricultural Experiment Station


irrigation with sewage was discontinued, and therefore decrease
in the percentage and quantity of these reserve foods in the
plants after irrigation ceased cannot be stated if such a de-
crease took place. The striking difference in the quantity of re-
serve food in the crowns of these plants in equal areas from
sewage-irrigated and from non-irrigated plots and the resultant
differences in silage yields appears to indicate the significance
of proper fertilization of some of our forage plants during their
first years of growth.

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







Annual Report, 1927


REPORT OF ANIMAL INDUSTRIALIST

Wilmon Newell, Director.
SIR: I submit the following report of the Animal Industrial-
ist for the fiscal year ending June 30, 1927.
Respectfully,
JOHN M. SCOTT,
Animal Industrialist.

There has been no change in the dairy herd except the pur-
chase of the Jersey bull, Reception's Stockwell 170369, from the
Fountain Plantation, Sycamore, Georgia. Reception's Stockwell
170369 is a half brother to Florida's Majesty 153431, the bull
that has made a marked improvement in the dairy herd during
the past few years.
Heifer calves from the best cows in the herd have been retain-
ed to replace the old and poorer cows in the herd. Several of
the poor producers in the herd were slaughtered during the year.

FEEDING TESTS

During the year a feeding test with Crotalaria meal and al-
falfa meal was conducted. This is, we believe, the first time that
Crotalaria meal has been used as a feed for milk production.
The feeding test was started March 16, 1927. Six cows were
selected from the herd for this test and were divided into two
lots. The reversal method of feeding was used, the feeding test
being divided into 28-day periods.
The first period started March 16, 1927, the second period
April 13, 1927, and the third period May 11, 1927.
In this test Crotalaria meal was compared with alfalfa meal
for milk production. The feed mixture used was as follows:
Crotalaria or alfalfa meal ..................... ...........125 pounds
Corn m eal ---.......... --..- -- .......-..... ..-- .. ...... ... 75 pounds
Ground oats ...... ........-.......- ................. ..... 50 pounds
Cottonseed meal .............-........................... 50 pounds
Peanut meal .................... -.......... -- .... 25 pounds

Each cow was fed 12 pounds of one of the above mixtures
per day.
The following are the analyses of the Crotalaria meal and the
alfalfa meal used in the test:


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Florida Agricultural Experiment Station


Crotalaria Meal Alfalfa Meal

Moisture -........ ...--............... 11.77 percent 11.77 percent
Ash .-....--.---------..... ---.... ------...... ......---.. 3.21 percent 9.23 percent

Fat .......-... --..... ..... ..-........- ... 1.36 percent 2.16 percent
Protein ....-------..--.--.----..--.--. 8.58 percent 12.56 percent
Carbyhydrates ...----------................... 27.08 percent 30.43 percent
Fiber ................ .......... ......... 48.00 percent 33.85 percent


The above analyses show that alfalfa meal is richer in food
elements than is the Crotalaria meal. However, the Crotalaria
meal used in this test was not made from the best quality of
hay. The Crotalaria plants were too mature when cut to make
a good quality of hay. There should be but little difference in
the analysis of Crotalaria meal and alfalfa meal when both are
made from the same quality of hay.

TABLE I.-MILK PRODUCTION RECORD OF COWS IN CROTALARIA-ALFALFA
MEAL TEST.
First Period-March 16 to April 12, 1927
Lot I, fed alfalfa meal Lot II, fed Crotalaria meal
Pounds Milk Pounds Milk
Cow No. 171 ......--........ 418.7 Cow No. 141 .............. 411.4
Cow No. 225 --............. 367.4 Cow No. 151 ............... 400.0
Cow No. 229 ............... 529.4 Cow No. 155 ............... 448.1

Total for period ......1,315.5 1,259.5
Second Period-April 13 to May 10, 1927.
Lot I, fed Crotalaria meal Lot II, fed alfalfa meal
Pounds Milk Pounds Milk
Cow No. 171 .............. 388.7 Cow No. 141 ................ 363.6
Cow No. 225 ............. 288.0 Cow No. 151 ................ 453.9
Cow No. 229 ............... 454.6 Cow No. 155 ............... 393.0
Total for period .... 1,131.3 1,210.5
Third Period-May 11 to June 7, 1927
Lot I, fed alfalfa meal Lot II, fed Crotalaria meal
Pounds Milk Pounds Milk
Cow No. 171 ..-...---....-. 335.5 Cow No. 141 .............. 294.8
Cow No. 225 ................ 314.0 Cow No. 151 ................ 399.7
Cow No. 229 ..........-..... 401.8 Cow No. 155 .............. 331.4
Total for period ..... 1,051.3 1,025.9
Total milk produced by feeding alfalfa meal---.....-..................3,577.3 pounds
Total milk produced by feeding Crotalaria meal......................3,416.7 pounds
Difference in favor of alfalfa meal ............ ....... .................. 160.6 pounds


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Annual Report, 1927


29R


TABLE II.-GAIN OR Loss IN WEIGHT OF COWS FED ALFALFA MEAL AND
CROTALARIA MEAL.
First Period-March 16 to April 12, 1927
Lot I, Fed Alfalfa Meal
Weight at Weight at Gain or
Beginning Close Loss
Pounds Pounds Pounds

'Cow No. 171 .................. 720 800 +80

,Cow No. 225 ........--....-- 872 901 +29

*Cow No. 229 .................. 700 752 +52


Cow No.

Cow No.

Cow No.


141

151 .

155









171

225

229


Cow No. 141

Cow No. 151

Cow No. 155


Lot II, Fed Crotalaria Meal
Weight at Weight at
Beginning Close
Pounds Pounds

-..-......... 848 950

.............. 859 946

......... 780 860


Second Period-April 13 to May 10, 1927
Lot I, Fed Crotalaria Meal
Weight at Weight at
Beginning Close
Pounds Pounds

....... .... 800 773

.............. 901 893

-.-.- 752 750


Lot II, Fed Alfalfa Meal
Weight at Weight at
Beginning Close
Pounds I Pounds

............i 950 927

........... 946 933

.--.. ---.... 860 831


Gain or
Loss
Pounds

+102

+87

+80





Gain or
Loss
Pounds

-27

-8

-2



Gain or
Loss
Pounds

-23

-13

-29







Florida Agricultural Experiment Station


TABLE II.-GAIN OR Loss IN WEIGHT OF Cows FED ALFALFA MEAL AND
CROTALARIA MEAL- (Continued).
Third Period-May 11 to June 7, 1927
Lot I, Fed Alfalfa Meal
Weight at Weight at Gain or
Beginning Close Loss
Pounds Pounds Pounds
Cow No. 171 .................. 773 800 +27
Cow No. 225 .................. 893 905 +12
Cow No. 229 .----.. ......... 750 734 -16


Lot II, Fed Crotalaria Meal
Weight at Weight at Gain or
SBeginning Close Loss
Pounds Pounds Pounds
Cow No. 141 ................I 927 919 8
Cow No. 151 ..--... ... 933 921 -12
Cow No. 155 .-..- .......- 831 I 827 -4


As stated above this is the first feeding experiment conducted
with Crotalaria meal. The results of this short feeding test
should not be taken as conclusive. In fact, it is planned to con-
tinue this experiment two or three months longer. Therefore
no conclusions have been drawn.

COMPARISON OF CORN SILAGE AND NAPIER GRASS
SILAGE FOR MILK PRODUCTION

Seven cows were used in this test. All cows were fed the same
grain ration; the only difference in feed was the kind of silage
used. The test began October 12, 1926, and continued until April
15, 1927.
The test was divided into two periods of 90 days each, with
five days between periods for change of feeds. During the 90
days the cows were fed corn silage, they produced 9,567.5 pounds
of milk. During the 90 day period they were fed Napier grass
silage, they produced only 7,053 pounds of milk, or a differ-
ence of 2,514.5 pounds in favor of the corn silage. This was a very
marked decrease in production when Napier grass silage was
fed.


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Annual Report, 1927


TABLE III.-MILK PRODUCTION OF COWS FED CORN SILAGE AND NAPIER
GRASS SILAGE.
Corn Silage Napier Grass Silage
Pounds of Milk Pounds of Milk
Cow Number Oct. 12, 1926 to Jan. 15, to April 15,
______J___ Jan. 10, 1927, Inclusive 1927, Inclusive

120 ....... ............ .... ... 1,300.5 772.4
152 .................................... 1,281.5 754.1
177 .................................... 1,697.2 1,011.8
191 .................. ...... ...... 1,494.3 1,131.1
219 .. ....... .... ...... ........... 1,074.8 937.2
296 .......................... ....... 1,421.6 1,250.1
297 .............. .................. 1,,297.6 1,196.3

Total ........~......................... 9,567.5 7,053.0

SWINE FEEDING

The swine feeding experiments were a continuation of feed-
ing experiments of previous years-tests of protein supple-
ments for corn. This test was a comparison of the value of fish
meal fed with corn, and cottonseed meal and alfalfa meal when
fed with corn.
Twenty-four hogs were used in this test. They were divided
into two lots of 12 each.
Hogs in let I were fed shelled corn and fish meal in the
proportion of n:ne parts corn to one part fish meal by weight.
Hogs in lot II were fed shelled corn nine parts, cottonseed
meal three-fourths part, and alfalfa meal one-half part by
weight.


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Florida Agricultural Experiment Station


TABLE IV.-WEIGHTS, GAINS, AND FEED CONSUMED BY HOGS TO MAKE 100
POUNDS OF GAIN.
(Both lots fed corn. Lot I was fed fish meal; lot II was fed cottonseed meal
and alfalfa meal.)
Lot I Lot II
Pounds Pounds

Weight at beginning of test December 9, 1926
(12 head) ............................................ ................ 938.30 930.00
Weight at close of test, February 11, 1927.--........ 1,453.30 1,170.00

Gain in 66 days ................... ............. 515.00 240.00
Average gain per head .------................. ....---... 42.90 20.00

Average daily gain per head ..........................-........ 0.65 0.30
Average daily gain per 1,000 pounds live weight.. 8.31 3.90

Pounds corn to make 100 pounds gain.................... 424.66 911.25

Pounds fish meal to make 100 pounds gain.............. 47.18 .. ........

Pounds cottonseed meal to make 100 pounds gain..-------.................... 75.93

Pounds alfalfa meal to make 100 pounds gain...........................--50.62

Total pounds feed to make 100 pounds gain...-..... 471.70 1,037.70

Feeds Consumed
Lot I Lot II
Pounds Pounds

Shelled corn ................... --- ...-.....-------- 1 2,187.00 2,187
Fish meal ......-----.......--..- ... ...---.-- 243.00 ...---

Cottonseed meal .------....---------- -------............ ------- 182.25

Alfalfa meal ......-----.. ...--- ----.......--......... ---121.50


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Annual Report, 1927


REPORT OF CHEMIST

Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Chemistry for the fiscal year ending June 30, 1927.
Respectfully,
R. W. RUPRECHT,
Chemist.

DIEBACK OF CITRUS

Further studies on the relationship of soil reaction to the ap-
pearance of dieback have shown no correlation between the soil
reaction and the occurrence of dieback. Pot experiments begun
last year for the purpose of studying the effect of disturbing
the carbohydrate-nitrogen ratio in the plants were continued,
but no significant results were obtained.
The diebackk" grove at the Citrus Experiment Station made
a normal growth and would have produced a good crop of fruit
if the cold weather in December and January had not frozen
a large part of the fruit. No dieback developed in any of the
plots. It is planned to transfer a large part of the work on this
problem to the Citrus Experiment Station, where a chemist will
be stationed, and where fresh material can be more readily ob-
tained than in Gainesville, which is out of the citrus belt.

SOILS STUDIES

The eight soil tanks have been refilled with Norfolk fine
sand and, after allowing the soil to settle for 11 months, they
have been planted to various legumes and non-legumes to study
the effect of green manures on the solubility of plant nutrients
in the soil, and the rate of loss of plant food through leaching.
The work in the tanks supplements more extensive field and
laboratory studies on the use of green manures to improve our
sandy soils. The field work is conducted in cooperation with the
Department of Agronomy.
In cooperation with the Department of Agronomy the rate
and degree of reaction change of the soil produced by different
nitrogen carriers on grass plots is being studied. The soil is a
typical Norfolk sand. Applications of ammonium sulfate and
ammonium phosphate have shown an increase in the soil acid-


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Florida Agricultural Experiment Station


ity, even at the end of six months, while applications of nitrate
of soda have shown a decrease in acidity.
A study of the cause of the harmful action of lime when ap-
plied to sandy soils also was begun. This is being conducted by
means of laboratory, field, and greenhouse studies.

NUTRITION STUDIES
CITRUS
The high vs. low potash fertilization experiment was continued
as outlined in previous annual reports (1922, p. 43R). As yet no
striking differences have been found in the general appearance,
taste, sugar or acid content of either oranges or grapefruit. Ash
analyses have shown a higher percentage of potash in the fruit
from potash fertilized trees. It is planned to determine whether
the higher potash content of the fruit has any effect on its
carrying quality.
The two experiments located at Vero Beach, on the East
Coast (1924, p. 50R), and at the Citrus Experiment Station at
Lake Alfred (1925, p. 30R), comparing the muriate, low grade
sulfate, and high grade sulfate of potash were continued. Fruit
from the grove at Vero Beach was sampled and analyzed. No
marked difference in either yield or quality of fruit, as deter-
mined by general appearance, taste, and chemical analysis,
was found.
The two experiments with Satsuma oranges in West Florida,
(1923, p. 50R; 1924, p. 50R) at Round Lake and Panama City,
made a good growth and came through the cold weather with-
out serious injury. It was noted that the trees receiving the
largest amount of ammonia were less defoliated by the cold than
those receiving lesser amounts. A good crop of fruit was set on
both groves despite the cold.
The citrus fertilizer experiment on the Everglades soils at
Davie (1926 Ann. Rept., 30R), had to abandoned as the hur-
ricane and flood of last September killed the majority of the
trees. A new experiment on a similar soil type will be started
this fall.
A new fertilizer experiment with citrus was begun at Lake
Alfred in a privately owned grove adjoining the Citrus Experi-
ment Station in cooperation with the Bureau of Plant Industry,
U. S. Department of Agriculture. Some of the newer forms of


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Annual Report, 1927


fertilizers, especially the concentrated salts, are being studied
in comparison with the usual commercial mixtures. A total of
180 orange and tangerine trees are being used.
Another new citrus fertilizer experiment was begun in Lake
County. In this experiment we are trying to determine the fol-
lowing:
1. Whether it is necessary to fertilize citrus three times a year.
2. Can all of the phosphoric acid and potash be put on in one
application and only ammonia applied three times a year?
3. What time of year is it best to apply the phosphoric acid and
potash?
4. Are we using more phosphoric acid and potash than is
necessary?
5. Are the new synthetic forms of ammonia as good a source
of ammonia as nitrate of soda or sulfate of ammonia?
A total of 606 trees, divided into 35 plots containing tanger-
ines, oranges, and grapefruit trees are being used.
TOMATOES
The fertilizer experiments with tomatoes, conducted in co-
operation with the Bureau of Plant Industry, in Dade County,
were continued. While two experiments were started one had
to be discontinued as most of the plants were killed by nema-
todes. The manganese-treated plots again produced the heaviest
yield, although the differences were not as great as last year.
Copper sulfate also gave some response, though not as great
as the manganese sulfate. More extensive studies on the effect
of manganese, iron, and copper salts are contemplated.
The experiments with tomatoes at Bradenton were conducted
as outlined in previous annual reports. Due to the prevalence
of wilt the yield on all of the plots was materially reduced and
it was impossible to correlate the yield with fertilizer treat-
ment. Manganese sulfate apparently did not give the beneficial
results that were obtained in the experiments in Dade County.
PECANS
The fertilizer experiments with pecans have been continued
as outlined in previous reports (1924, p. 48R). A crop of nuts
was gathered from most of the orchards. A total of 135 samples
of nuts were taken and analyzed. The only difference that could
be correlated with the fertilizer treatment was in the potash


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36R


Florida Agricultural Experiment Station


experiments. On four varieties of nuts, Schley, Curtis, Moore,
and Moneymaker, the nuts from the no-potash plot had a lower
fat content and a higher protein content than nuts from trees
that had received a complete fertilizer containing potash.

CELERY
The celery experiments carried on in cooperation with the
United States Department of Agriculture, at Sanford, were
discontinued with the harvesting of the celery this spring. All
of the plots made rather unsatisfactory growth. However, the
experiment with concentrated fertilizers again showed that these
fertilizers can be used successfully. The yields from the plots and
the composition of the fertilizer mixtures used are shown in
Table V:

TABLE V.-CONCENTRATED FERTILIZER EXPERIMENT WITH CELERY AT
SANFORD, FLORIDA, 1927.
Plots 1/40 acre, 4 rows, 100 feet long, two inside rows cut for record-
1/80 acre. Fertilizer application, formula 6-6-6. Each fertilizer con-
tains equivalent amounts of plant food (P20,- NH3-K-,O). Pounds of
material per ton on a 6-6-6 basis.
Concentrated Fertilizer
Materials Pounds Applied to
Each Plot Commercial Fertilizer
A B D E F Pounds Applied to Plot C

Ammo.-phos. -........----196 250 250 250 .......
Potassium ammon. Acid phosphate, 16%..-... 750
phos .--................... 46 ............. ..... -
Potassium sulfate, 50%.. 240
Potassium nitrate 255 .............
'4 cottonseed meal, 8%.. 375
Ammonium nitrate 108 ..... ---- -... ....
1/ fish scrap, 10%....---- 300
Urea -............ ----....-- 147 .--.. ...- 203
/' amm. sulfate, 25% -. 120
Cottonseed meal ..- 67 71 83 90 79
1/5 sodium nitrate 19%.- 160
Ammonium sulfate -.....--.--.... .. 321--..
| Filler --------- 55
Potassium sulfate ..-.......240 240 1240 240
Ammonium chloride ............... 257 ....
Triple phosphate ....----... ...----.--.------ 267

Total ---................. 672 708 1830 901 789 2000'
Yield in celery in I
pounds for 1/80
acre ..----..............-- .. 572 31 560 456 748 436





Annual Report, 1927


MISCELLANEOUS

The experiments with tobacco at the sub-station at Quincy
were discontinued until a shade can be constructed on new
ground, as the old shade is badly infested with nematodes, which
have affected the yield in such a manner that the effect of the
various fertilizer treatments could not be determined.
The potato experiments at the Everglades Station were con-
tinued. The yield of potatoes was severely cut down by the pre-
valence of a disease which has not yet been positively identified.
The infection was fairly general over the entire field. The out-
standing increases in yield were found on the plots receiving
potash. The yields on these plots were greater in every instance
than on those without potash. Copper sulfate apparently had
no marked influence in increasing the yield.
In addition to the potato experiments, six long-time experi-
ments were begun in cooperation with the Department of Ag-
ronomy and the Everglades Station Staff, but were discontinued
after the flood and the hurricane.
The research work at the Everglades Station was enlarged
during the past year through the equipping of a soils and chem-
ical laboratory, and the appointment of R. V. Allison. A great
deal of Dr. Allison's time was devoted to a general survey of
problems with which the farmers of the Everglades are con-
fronted, and the equipping of the laboratory. Work was begun
on a study of the effect of a large number of chemicals on crop
growth on saw-grass land as well as the study of the effect of
these chemicals on the microflora of the soil. (For detailed re-
port of this work see report of Everglades Experiment Station.)
In addition to the work on the problems, a considerable num-
ber of soils were tested for acidity for individuals and County
Agents, and several minerals tested for phosphates and calcium
carbonate. Also an analysis was made of the water from the
deep well at the Everglades Station. (See that report-for com-
position of water.) As heretofore, a number of analyses were
made for various departments of the Experiment Station in
connection with work on their problems.


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Florida Agriculturzl Experiment Station


REPORT OF COTTON INVESTIGATIONS
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Cotton Investigations for the fiscal year ending June 30, 1927.
Respectfully,
A. F. CAMP,
Plant Physiologist in Charge.


COTTON PATHOLOGY AND PHYSIOLOGY
The work in cotton pathology and physiology was continued
by Dr. M. N. Walker who took up his duties as Assistant Cot-
ton Specialist on December 1, 1926. His report follows.
Work was begun December 1, 1926 on the relation of soil
temperature to the germination of cotton seed, to the growth of
cotton seedlings, and to the ,ore-shin disease of cotton, con-
tinuing work already started along this line.
Soil temperature was found to exert a very marked influence
on the germination of cotton eed. It was found in eight trials
that the most rapid germination occurred between 340 and 350
C. Above 380 C. there was a slowing up in germination and at
400 C. no germination took place. At 150 C. germination was very
slow, taking from 18 to 20 days, and it is probable that the low-
est limit is but very few degrees lower than this temperature.
Lightning Express No. 3 and Express No. 432 were the varie-
ties used in these trials.
The records on six series cn the growth of cotton showed
comparatively little effect of soil temperatures between 22.5
C. and 350 C. other than the more rapid germination at the
higher temperatures. It appeared that factors other than soil
set the limit on growth between the temperatures named. At 380
and 390 C. cotton plants grew very poorly, showing a decidedly
adverse effect from the high temperatures on the roots, and
at 400 C. no germination occurred. The varieties tested were the
same as those used for the tesis on germination.
Nine series with Lightning Express No. 3, Lightning Ex-
press No. 432, and Cook 307-6( were run to determine the soil
temperature at which the greatest injury from the sore-shin
fungus (Rhizoctonia) took place. It was found that germination
was practically inhibited at 24:.50 C., though between 15 and


38R






Annual Report, 1927


300 C. the percentage of killing was also very high. Above 30
C. the percentage of killing decreased rapidly and reached zero
at 35"C. At 15 C. killing usually occurred after the plants were
up and was slow, showing a decided decrease in the activity of
the fungus.
To determine the effect of temperature on the fungus alone,
cultures of the fungus on potato dextrose agar were placed in
soil cans. Five series were run and showed the probable optimum
temperature for the growth of the fungus to be in the neighbor-
hood of 270 C. At 34.50 there was very weak growth, and at
38.50 no growth. At 110 C. the growth was very scant. The limit
of growth at low temperatures is probably around 90 C.

COTTON BREEDING
The following is the report of Dr. W. A. Carver, who is in
charge of the work on cotton breeding.
During the summer of 1926 a variety test including six of the
most promising varieties previously tested were planted in four-
row (372 feet long) triplicate plots. One of the six varieties,
Lightning Express No. 4, was planted as check in alternate plots.
In this test, the varieties Cook 307-6 and Trice yielded highest,
followed in order by Dixie Triumph, King 29, Lightning Express
No. 4, and Cleveland No. 6. Lightning Express No. 4, a high
yielder in former years, was much less productive in 1926, due
possibly to the fact that two-year-old seed were planted.
In a single-row (300-foot triplicate rows) variety test includ-
ing 42 varieties, Rhyne's Cook, Willis, Cook 307-6, Covington
Toole, Lewis 63, and Lightning Express No. 6 yielded highest
among the wilt-resistant varieties and Bottom's Prolific, Whit-
ing's Prolific, Trice, and Mexican Big Boll among wilt-suscep-
tible varieties.
During the present year a single-row (300 feet long) test of
16 varieties is being conducted. Also there has been planted a
strain test of Lightning Express No. 3 including 11 strains and
a strain test of Council Toole including four strains. A few of
these are showing their superiority over the parent variety from
which they were selected in 1924.
Plant selections were made in 1926 from the most promising
varieties, as in former years, selecting productive plants show-
ing early maturity, freedom from disease, open branching, small


39R






Florida Agricultural Experiment Station


leaves, and medium sized bolls which open rapidly and well. The
following list gives the most promising varieties as indicated
by previous variety tests and the number of selections chosen,
after laboratory inspection, for testing in plant rows in 1927.
Number of
Variety Plant Selections
Planted in 1927
Hybrid (Lightning Express No. 3 X Council Toole) ........ 5
Hybrid (Lightning Express No. 4 X Council Toole)...-.... 158
Lightning Express No. 3 .........-------..--------- 35
Lightning Express No. 4---------- -------------- 50
Council Toole ...........------ -------------------*--- 36
Cook 307-6 ------------ 5
The hybrids listed above were planted on the heaviest wilt-
infested soil available in order that the most resistant hybrids
might be determined. Several of the progenies resulting from se-
lections in hybrid strains and standard varieties look promising
at present.

BOLL WEEVIL INVESTIGATIONS

The following is the report of E. F. Grossman, who is in
charge of boll weevil work.
POISONING THE BOLL WEEVIL
Sixty 1/8-acre field plots, separated with corn barriers, were
used for making a comparison of the cost and effectiveness of
several methods of controlling the weevil. Dusting with calcium
arsenate was compared with:
1. The Florida method with one and two applications of syrup
poison after the square stripping.
2. The Florida method with one and two applications of
calcium arsenate dust after the square stripping.
3. Dusting with a 50-50 mixture of calcium arsenate and hy-
drated lime.
4. Mopping with a syrup mixture throughout the poisoning
season.
5. Mopping with a syrup mixture until the cotton bloomed
heavily, and calcium arsenate dust for the balance of the season.
As soon as the cotton squares became visible the first appli-
cation of poison was made, followed at four or five-day inter-
vals for the succeeding four weeks. Six applications of poison
were made during the month of June, during which time there
were 8.01 inches rainfall. Four of the six applications were ef-


40R






Annual Report, 1927


fective. The third and fourth were washed off shortly after
they were applied. No poison was applied during July and Au-
gust, which had 7.03 and 7.00 inches of rainfall, respectively.
By directing the entire poisoning against the hibernated wee-
vils, the most economical method of poisoning was followed.
The results were similar to those obtained during four years
of boll weevil field poisoning carried on in southern Georgia.
Calcium arsenate dusting was slightly in the lead, followed
closely by the 50-50 mixture of calcium arsenate and hydrated
lime. The syrup mixture blocks showed up practically as well
as the calcium arsenate dust, which would be expected when
following an early poisoning program. In previous experiments,
however, when the syrup mixture plots were poisoned along with
calcium qrsenate plots through July and August, the cotton
plants were so large that the syrup could not be efficiently mop-
ped onto the plants. This caused a decided difference in weevil
control, the dusted plots yielding far more cotton. But when
early poisoning is followed the cotton plants are small and
mopping with syrup mixtures becomes as efficient as dusting.
Cotton treated by the Florida method (which consists of
stripping off squares about June 5, followed by one or two ap-
plications of poison) suffered from reinfestation by hibernated
weevils which arrived in the field after the square stripping and
poisoning had been completed.
Numerous infestation counts and field observations made dur-
ing the entire season showed that the cotton poisoned early did
not require poison during July and August. Practically all of
the hibernated weevils had been killed and both a bottom and
middle crop were set and amply protected.
HIBERNATED WEEVILS INFESTING THE FIELD

Though the emergence of the boll weevil from hibernation,
when placed in cages, has been recorded for numerous points in
the cotton growing area since 1906, there have been no actual
data acquired on the entrance of the hibernated weevil into the
cotton field. Control of the weevil consequently was first based
on the presence of flared squares which indicated the presence
of a sufficient number of weevils to demand control measures.
Later the cotton grower was advised to examine the field care-
fully and start poisoning when 10 percent of the squares were


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Florida Agricultural Experiment Station


weevil punctured. Then the "pre-square" method of poisoning
was found to be the most effective in gaining an earlier control
of the infested fields.
Field observations for a number of years and actual weevil
counts in plots of cotton planted in weevil infested areas for
two years yielded data that are more valuable with regard to
poisoning than any previous hibernation cage data.
The following method was employed for obtaining data on
the entrance of the hibernated boll weevil into the cotton field:
A well infested cotton field was selected for the following sea-
son's planting. The next spring only three-fourths of an acre of
this field was planted in cotton, and thinned out to about 3,500
plants. Plants were examined three times a week and all wee-
vils were captured and recorded as they appeared in the field.
In 1926 the weevils started to enter the field at Gainesville
on May 10, and continued to enter the field until the first week
in July, when the tri-weekly counts showed a decided drop. The
greatest infestation was on June 20.
In 1927 the first weevil found in the field at Gainesville was
on April 27, and in Aucilla, April 28. Weevils continued to enter
the fields until the greatest number of new hibernated weevils
entering the field was on June 13, after which the tri-weekly
count dropped, until by July 1, the field yielded few weevils.
On the other hand, cage hibernation data obtained under the
same weather, and, as far as possible, the same hibernation
conditions, showed a much earlier peak of emergence and also
a much smaller percent emergence during the month of June.
In the field a very strong correlation between the cotton con-
dition and the weevil emergence was consistently noted. Where
the soil and temperature conditions favored good cotton growth,
they also favored weevil emergence, as shown by an examina-
tion of 10 cotton fields at the same intervals which showed the
arrival of weevils both earlier and later than the peaks in field
entrance, depending on the location of the fields.
The conclusion reached was that the most effective and eco-
nomical method of poisoning was to begin as soon as the cotton
first squared and to continue for about four weeks, by which
time it was found that practically all the weevils emerging from
hibernation in the open had found their way to the cotton
fields.


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Annual Report, 1927


REPORT OF ENTOMOLOGIST
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Entomology for the fiscal year ending June 30, 1927.
Respectfully,
J. R. WATSON,
Entomologist.


THE GREEN CITRUS APHID APHISS SPIRAECOLA
PATCH)

This comparatively new pest of citrus continued to receive
the greatest amount of attention from the department. All the
time of Ralph L. Miller, Assistant Entomologist, and that of W.
L. Thompson from March on was taken up in investigating this
insect. The damage done by this aphid in the groves during the
spring was much less than during 1924 and 1925. This was un-
doubtedly due to the fact that there was very little new growth
on citrus trees during the winter, especially after the freezes
of early January. Consequently starvation reduced the number
of the aphids to such a low point that, when the spring flush
of growth did start, they were unable to severely infest it be-
fore it became so mature as to be immune to their attacks.
Life history studies were carried on at both Lake Alfred and
Gainesville, as it was anticipated that these two stations (150
miles apart), one in the center of the citrus belt and the other
on the extreme northern edge, might show quite different be-
havior of the aphids, especially during the winter. A compari-
son of the records of A. N. Tissot at Gainesville and Mr. Miller
at Lake Alfred shows this anticipation to have been well found-
ed. Except during a few brief periods when it was too cold, the
weather at Lake Alfred during late fall and winter, October 15
to March 1, was the most favorable of the whole year for the
development of the aphids. During this period, when well sup-
plied with succulent food, they produced the largest number of
young per day and the developmental period was the shortest.
During this period at Gainesville, both reproduction and growth
were the slowest of any period in the entire year. In both lo-
calities these studies were carried on out of doors on young nur-
sery trees.
This explains why the aphid has never been so injurious in


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Florida Agricultural Experiment Station


the northern part of the citrus belt and indicates that it never
will be, except perhaps during exceptionally warm winters. Evi-
dently about 720F. is the critical temperature. When the average
daily temperature drops below this, growth and reproduction
are greatly retarded. When constant temperature chambers,
which are now being constructed at Gainesville, are completed
it will be possible to determine the effects of temperature much
more accurately.
As during previous winters eggs were laid at Gainesville. Mr.
Tissot found the first nymphs which were to develop into ovi-
parous females on Spiraea on November 7. Adult males appeared
on November 12. Eggs were laid on Spiraea, apple and sand
pears from November 15 to December 18. On January 18 the
eggs on the sand pears began to hatch. This is the first time the
eggs have been observed to hatch in Florida. During previous
years they have uniformly failed to hatch. The successful hatch-
ing of eggs during the past winter shows plainly that cold will not
exterminate the aphids.
On the other hand the heat of summer, too, slows up the rate
of both growth and reproduction, though not to the same extent
as the cold in winter at Gainesville. It would thus seem that se-
vere outbreaks of the aphids will always be confined to the early
spring and especially to seasons when a warm moist winter, free
of destructive freezes, is followed by a cold or dry spring which
extends the flush of growth over an abnormally long period.
PREDATORS
The life histories, seasonal abundance, food preferences, and
super-parasites and diseases of the chief predators, ladybeetles,
syrphus flies, and aphis-lions have now been worked out much
more thoroughly than has ever been done before. In addition,
the daily consumption of aphids by each species has been deter-
mined and also the relative number of aphids and predators
throughout the entire year. In this way data have been obtained
as to the efficiency of each predator.
At times the predators have taken 10 percent of the entire
number of aphids, per day, on the observed trees. This percent-
age is too low to allow the predators to check an outbreak of
aphids when conditions of temperature and food are favorable
for the development of the latter; but shows that they are of
much value in checking an infestation when conditions for


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Annual Report, 1927


aphid reproduction are less favorable, as during the summer and
early fall. Also their activities may result in cleaning up the
residue of aphids left after spraying or dusting, or in delaying a
reinfestation. This has shown the importance of choosing for
insecticides those, such as tobacco products, which do not kill
many of the predators.
These predators have been found to be highly parasitized by
super-parasites; especially by hymenopterous insects and fun-
gous and bacterial diseases.
CONTROL
The experience of the past season has emphasized even more
the efficacy of a thorough cleanup of the aphids during the
winter and the hastening, by fertilization and cultivation, of
the spring flush of growth.
As very few of the aphids develop wings during the winter, a
grower's efforts to clean up his grove at that time are not hinder-
ed by migration from neighboring groves. Not until growth be-
gins to harden, on at least some of the trees, does a general
flight of the aphids take place. This year this occurred about
March 15.
Among the many insecticides tried, two seem to be an improve-
ment over the 3 percent nicotine sulphate-lime dust heretofore
found most effective. Mr. Miller found that by making up this
dust with sulphur substituted for half the hydrated lime, a very
light dust was obtained that worked well in the dusters. It seemed
even more effective than that in which lime only was used as
a carrier, and controlled rust mites and red spider at the same
time. It appeared that under favorable atmospheric conditions
-warm, calm weather-a 2 percent dust was effective. This
would reduce the cost considerably.
The other promising insecticide was a very finely divided to-
bacco dust (snuff No. 2) analyzing 2 percent nicotine. When ap-
plied to trees wet with dew or rain this was found very effec-
tive, but was inefficient on dry trees. It is much cheaper than the
3 percent nicotine sulphate-lime dust.

ROOT-KNOT

The work looking towards control of the root-knot nematode
was continued. Plots treated with calcium cyanide in comparison
with those treated with sodium cyanide and ammonium sulphate


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Florida Agricultural Experiment Station


(as described in Bulletin 159) indicated that the latter was
preferable in spite of the greater expense. The control of root-
knot was more satisfactory and the fertilizing effects of the
residue, as shown by the growth of the plants, was much greater.
The tests of calcium cyanide on peach trees infested with
root-knot nematodes, carried on at De Funiak Springs in co-
operation with the horticulturist of the L. & N. Railroad, were
concluded. The peach trees were interplanted with pecans and
the growth of the latter necessitated the removal of the peach
trees. At the time of their removal they were carefully examined
for root-knot and measured. The trees on the treated plots were
appreciably freer of root-knot and of a larger size than untreat-
ed trees. The plots receiving a total of 1,000 pounds of calcium
cyanide per acre per year showed the best results and of these
the plot in which it was given in four applications (March, May,
July and September) showed less root-knot than those in which
the same amount was given in one, two or three applications
per year.
The trees receiving the material in dosages much over 250
pounds per acre or a total yearly application of 1,500 pounds per
acre were manifestly injured by the material. It is planned to
start a new series of experiments with young trees and to in-
clude figs as well as peaches.

THE FLORIDA FLOWER THRIPS
Frankliniella tritici bispinosa (Morgan)
The numbers of Florida flower thrips infesting citrus bloom
were so small that no good opportunity was afforded for trying
control measures.
A heavy infestation on strawberry blossoms afforded an op-
portunity to try out various insecticides. Derrisol (1:800) was
an almost complete failure, only about 10 percent of the insects
being killed. Nicotine sulphate spray (1:800) killed nearly 90
percent. Even better results were obtained by dusting the plants
with a mixture of equal parts of sulphur and finely ground to-
bacco ("snuff No. 2") analyzing 2 percent nicotine. This not
only killed the thrips in the blossoms but acted as a repellant
and delayed reinfestation for several days. It has the added ad-
vantage of also controlling red spiders. This mixture would seem
to be a real contribution to the control of small insects on truck.


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Annual Report, 1927


INTRODUCTION OF BENEFICIAL INSECTS

Arrangements were made through the Tropical Research
Foundation for the introduction from Cuba of the Tachihid par-
asite (Loxophaga) of the cane borer and a considerable number
of pupae have already been received and the adult flies liber-
ated. In order to guard against the possibility of introducing
secondary parasites, the pupae are allowed to hatch in the lab-
oratory in a tight cage from which the secondary parasites can-
not escape. The adult flies are taken from the cage as they
hatch out and liberated in infested fields. All secondary para-
sites are killed as soon as they emerge from the pupae. This
work will be continued on a larger scale during the coming year.

PECAN INSECT INVESTIGATIONS
In order to amplify the pecan insect work carried on last
year and up to September 1 of this year, a field laboratory for
the study of insects and diseases of pecans was established at
Monticello in cooperation with the pecan growers of that place,
who supplied the laboratory and some equipment. Fred W. Walk-
er was placed in charge of the insect investigations. He com-
menced work on February 1.

THE SHUCKWORM (Laspeyresia caryana Fitch)
This insect, which was formerly considered as one of minor
importance, was this year a serious pest, if not the most im-
portant one of the pecan in the Monticello region. An average
of nearly 75 percent of the husks gathered during the spring
showed infestation of this species.
An experiment was started to determine whether the turning
under of the fallen husks would be of any benefit in controlling
this insect. A summary of this work is as follows:
Emerging from surface, 51 percent.*
Emerging from a one to four inch covering of sandy loam, 4.75 percent.
Emerging from clay (1 inch), 7 percent.**
Emerging from clay (2 to 4 inches), 0.
From the above figures it would seem that a good control
can be secured by plowing in the husks, especially in the heavy
soils. The percentage of control would also depend largely upon
*Remainder destroyed mostly by parasites.
**From husks uncovered by heavy rain.


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Florida Agricultural Experiment Station


the thoroughness of the plowing. Any plowing which is done to
control this pest must be done between the end of harvest
and the middle of February. The first adult emerged from the
husks on February 15. The majority of the adults from the
overwintering brood emerge between March 15 and April 1.
Larvae of the first spring brood have been found in the nuts of
hickory and Phylloxera galls.
An experiment is being run to determine the percentage of
nuts destroyed by the shuckworm. In this experiment all fallen
nuts are being picked up from 10 trees of Moneymaker. These
nuts are examined to determine as far as possible the cause of
their dropping. Below is a summary for June.

Cause of Drop Number of Nuts Percentage

Shuckworm ......-- -------- 851 59.34%
W eevil ...............--------- 150 10.46%
Nut case-bearer ......------ 53 3.69%c
Squirrel ........ ...-- ----....... 1 0.07%
No apparent cause .............379 26.43%
1,434 99.99%C/

NUT CASE-BEARER
Larvae of the spring brood of nut case-bearers were found
entering the nuts on May 13. The percentage of infestation this
season was generally light. A few trees of the Moore variety,
however, showed a high percentage of infestation. Larvae from
this brood were brought into the laboratory and placed on
nuts to observe their feeding habits. These observations were
taken under the microscope. In no case did the larvae eat the
outside portions of the nut. This portion was merely pried loose
and discarded. Other larvae were placed on field sprayed nuts
which were brought into the laboratory. These nuts were placed
so that the larvae were forced to enter the nut through a heavily
sprayed area. All of these larvae were bred through to the
adult stage without apparent injury from the spray. Each of
these larvae had entered an average of two sprayed nuts.
Field experiments are being run to determine if there is any
benefit derived from spraying with arsenate in the control of
this insect. These experiments will be modified next year to de-


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Annual Report, 1927


termine whether the spray acts as a repellant or if the insects
are really killed.
LEAF CASE-BEARER
A check was made of last season's spraying on the Crane place
at Mandarin for the control of the leaf case-bearer. The sprayed
trees show a control of from 80 to 90 percent over the checks, de-
pending upon the strength of the arsenate used.

TREE CRICKET Oecanthus Angustipennis Fitch

Numerous egg punctures of the tree cricket were found in the
small branches of the pecan. In some cases the twig had died
above the puncture. In most cases, however, the twig does not
die, but a long scar is left, which lasts for a period of at least
three years before healing over. Twigs in which the eggs have
been laid are weakened considerably. The nymph of this species
may be classed as a beneficial insect, as its food consists prin-
cipally of aphids. The only damage is done by the female de-
positing her eggs in the twigs.


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Florida Agricultural Experiment Station


REPORT OF ASSOCIATE HORTICULTURIST
Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Horticulture for the fiscal year ending June 30, 1927.
Respectfully,
A. F. CAMP,
Associate Horticulturist.

The working force of this department was greatly strength-
ened during the year. Dr. A. F. Camp, Plant Physiologist in
charge of cotton investigations, was transferred to the depart-
ment as Associate Horticulturist, effective July 1, 1926, to take
up fruit studies, particularly a study of the fundamental physi-
ology of fruit production. M. R. Ensign was appointed Assistant
Horticulturist in Truck Crop Work, on October 1, 1926, giving
the greater part of his time during the year to phenological
studies on truck crops in Florida.
During the past year considerable time was spent in obtain-
ing a better knowledge of the horticultural problems of the
state. A general survey was made of various crops, particularly
citrus. Considerable time was also spent on pears, blueberries,
avocadoes, grapes, and like fruits.

SPLITTING OF ORANGES
During the fall of 1926 a large number of inquiries were re-
ceived concerning the splitting of oranges, and a survey of the
citrus area was attempted. The type of splitting referred to is
the splitting of apparently normal fruits, particularly Valencias,
during the fall and particularly during the months of September,
October, and November. The splitting is longitudinal, starting
at the blossom scar and frequently reaching almost to the stem.
This splitting is distinct from that accompanying ammoniation,
since the oranges are normal as to size and texture and split
longitudinally, while the ammoniated fruit is small, has a hard
rind and frequently splits transversely.
Splitting was found to be particularly bad on Valencias though
a number of other varieties that are less frequently planted, such
as Mediterranean Sweets, Hamlins, and some miscellaneous va-
rieties were found to be almost equally affected. Pineapples and
seedlings were ordinarily less affected. This trouble was found


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Annual Report, 1927


to be more severe on young trees than on old trees, but likely to
be severe on trees up to 10 or 11 years old. A large number of
counts on young Valencia trees in the area lying from Haines
City to Sebring showed a very high percentage of split fruits
by November. Some of these counts are given in Table VI.
TABLE VI.-A COUNT OF ORANGES FOR SPLITTING ON 21 VALENCIA TREES
IN THE RIDGE SECTION.


Number of Fruits on the Tree
and on the Ground

Tree Split Normal
1 261 150
2 86 40
3 140 70


4
5
6
7
8
9
10
11


Number of Fruits on the Tree
and on the Ground

Tree Split Normal

12 60 134
13 54 111
14 52 95
15 47 32
16 23 87


74
68
*- Y


17
73
78
101
72


These trees were picked at random and give as nearly as
possible the average condition in the groves examined.
Splitting was probably worse in the "ridge" area than in
other areas, being largely correlated with the distribution of the
light sandy soil, common to much of that area. However, some
very severe cases of splitting were found on much heavier soils,
notably on the flatwoods soils in Hillsborough County. This lat-
ter fact leads naturally to the conclusion that there is some
factor in the grove treatment as well as soil and weather con-
ditions that contributes to this trouble.
The rind of fruits, iri groves where splitting was taking
place, was found to be under a high tension due either to shrink-
ing of the rind (which is unlikely) or to an abnormally rapid
swelling of the pulp. Just how this internal pressure is brought


II

(i

i.


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Florida Agricultural Experiment Station


about is difficult to say, but it is probably due to an abnormal
condition affecting the hydration of the tissues and resulting in
an over-supply of water in the fruit.
A common "remedy" is the plowing of a furrow close to the
tree rows to cut off a large number of feeding roots. This prac-
tice is based on the belief that it will reduce the amount of
water carried to the fruit. From what was seen it is doubtful
if this treatment is effective, though in no case were checks
available for careful comparison. The addition of various potash
carriers, including double manure salts, failed to produce any
reduction in splitting. In some cases growers claim to have had
good results from the use of copper sulphate, though it is
doubtful if much good was obtained in this way, since some of
the most severely affected groves were heavily treated with
copper sulphate.
COLD INJURY-CITRUS
Following the severe cold weather of the past winter the
Associate Horticulturist and E. F. DeBusk, of the Agricultural
Extension Division, traveled over the citrus area to observe
the results of the cold. It was evident that growers had become
careless during the last few years concerning cold protection. A
great deal of grove acreage has been planted in low places where
there is no adequate air drainage and these areas were severely
injured. Very little banking had been done and the damage was
often greatly increased on this account.
In a few instances very excellent results were obtained from
heaters, and crops as well as trees were saved. The results ob-
tained by heating varied greatly, depending upon the conditions
in and around the grove, and indicate the necessity for a care-
ful study of the factors influencing artificial heating.

FRUIT PRODUCTION-CITRUS
Work was started on a project on fruit production, and
weekly measurements were started at Lowell and at Gainesville.
The Parson Brown and Pineapple oranges were used at Lowell
while at Gainesville the Valencia orange and Walters grapefruit
were used. One hundred fifty specimens were used in each
case. Measurements were started on May 4 when the usual shed-
ding, immediately following blooming, was past and the fruits


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Annual Report, 1927


were mostly from 15 to 25 mm. in diameter. The drouth condi-
tions were severe at Gainesville but were tempered by showers
at Lowell, where the soil was likewise much more retentive of
moisture. As a result over half the fruits that had been tagged
at Gainesville were shed before the rains started and new ones
had to be tagged to take their places, while the shed at Lowell
was very light. Material is being collected for sectioning juice
sacs and this and the measurements will be continued throughout
the season.
TEST GROUNDS
The work on the test grounds, under Assistant Horticulturist
Harold Mowry, for the year has been chiefly along lines pre-
viously inaugurated in the introduction and testing of various
plants which include both fruits and ornamentals. The acquisi-
tion of additional acreage has made possible an appreciable in-
crease in the size and variety of plantings, which heretofore
have been restricted by the lack of available planting space.
Through the active interest and cooperation of various Offices
of the Bureau of Plant Industry of the U. S. Department of Ag-
riculture, over 100 species or varieties of plants, in addition to
those secured from other sources, have been added to the plant-
ings during the year.
STRAWBERRY
In cooperation with the State Plant Board the tests of straw-
berry hybrids and varieties have been continued at Starke and
Plant City. In addition to those previously reported, two varie-
ties, Famous and Stewart, were added to the plantings as were
also Missionary plants obtained from widely separated sources.
Both the Stewart and Famous varieties gave better results in
amounts of fruit produced than did any of the varieties, with
the exception of Missionary. Many of the hybrids made an ex-
ceptional vegetative growth but none produced fruit in quantity
sufficient to make them desirable for commercial planting.
Negligible differences were noted in amounts and quality of
berries produced by Missionary plants obtained from Maryland,
Arkansas, and two Florida sources. Of the 46 varieties and hy-
brids under observation none has equaled the Missionary in pro-
ductivity and at this time no other variety can be recommended
as being better for Florida commercial planting.


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Florida Agricultural Experiment Station


Fig. 3.-Showing growth of tung-oil trees in plantings on the horticultural
grounds of the Experiment Station. Planted in January, 1923. Upper
photo made in November, 1923; lower photo made in June, 1927.
TUNG-OIL
Additions to tung-oil plantings consist of some budded stock-
the scions of which were from parent trees having desirable
characteristics, seedlings from self-pollinated blooms, and some
seedlings from seeds originating in widely separated regions in
China. Experiments are now being conducted on the top-work-
ing of large trees which are proving to be shy bearers. Trees of
Aleurites montana (Mu-oil trees) have bloomed and set fruit
this season for the first time. This species seems to be more
vigorous in growth but less hardy than A. fordi.
CITRUS
Eighteen varieties or strains have been added to the Satsuma
plantings. Most of these have not been tested in the United


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Annual Report, 1927


States and as some are reported to be very early in maturing,
an excellent opportunity is offered to determine the value of
these as compared to the Owari, the standard variety at present.
BULBS
Fertilizer experiments were inaugurated the past season with
paperwhite narcissus, 24 plots being included in the tests.
MISCELLANEOUS
In addition to numerous species of ornamental shrubs, the
following have been planted during the past season:
Japanese persimmon 18 varieties
Plum 22 varieties
Blueberry % acre
Bamboo 18 species
Ornamental trees 17 species
Berry (Rubus sp.) 4 varieties
Pear 8 varieties
Grafted figs (see Annual Report of 1925) for planting two
half-acre blocks have been supplied by this Department for
planting in Broward and Sarasota counties. Previous plantings
were partially or wholly destroyed by the storm of September
18, 1926, so that as yet no truly indicative results as to the
value of the rootstock have been obtained. Observations of this
stock in Gainesville show little nematode infestation after three
years in the field.
Various methods are being tried in the endeavor to find a
simple and practical way of successfully rooting blueberry cut-
tings. The most satisfactory results thus far have been obtained
from eight to 12-inch cuttings of wood of the previous season's
growth, taken during the midwinter months. These were insert-
ed about two-thirds of their length in outside beds in a very
sandy soil. The sand was kept moist at all times. No covering
was used until the advent of warm weather when an approxi-
mate half shade with slats was provided. Six to eight months
have been required for the starting of root formation.
That roses can be successfully grown under glass in Florida
has been proven by experiments conducted in the greenhouse
during the past two years. The following varieties were grown:
Templer, Ophelia, Mme. Butterfly, Columbia, Mrs. Aaron Ward,
Premier and Crusader. With the exception of Crusader all of
these varieties made very satisfactory stems, foliage and blooms.
All were grown on their own roots. Plantings made in mid-Sep-


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Florida Agricultural Experiment Station


tember, of plants from four-inch pots, averaged 25 1/3 blooms
per plant up to the time of drying off and cutting back the fol-
lowing May 15. During the optimum growing season salable
bloom buds were produced in 27 days from the beginning of
vegetative growth of the bud producing the stem.

STUDIES ON TRUCK CROPS
M. R. Ensign took up his duties as Assistant Horticulturist,
on October 1, 1926, to study truck crops. His report follows.
Potato yields on the same piece of ground with similar cultu-
ral care have shown wide variations from year to year. These
differences have been vaguely accounted for on the basis of fav-
orable or unfavorable weather. In an effort to determine what
elements or factors of the weather were responsible for yield va-
riations, six rows of potatoes were planted on a uniform piece
of ground in the LaCrosse section. The first planting was made
on January 10, and each successive planting was made at seven-
day intervals thereafter, so that the last row was planted Feb-
ruary 14. Cultural conditions, size of seed piece, planting dis-
tances, and amount of fertilizer were as near the same as could
be secured on all the rows in the experiment.
Soil temperatures in the center of the ridge at a depth of 8.9
centimeters, the average depth of the seed pieces, were secured
by the use of a soil thermograph. At weekly intervals, soil mois-
ture determinations on the basis of oven dryness were made at
one and two foot depths.
All the rows were dug between April 29 and May 4. Hence
the rows were of varying age as calculated from the planting
to the harvesting. The length of growing period for each plant-
ing is shown below.
Row ......... ......................... I II i II IV V I VI
Growing Days .- ...... 110 104 98 93 85 79

On March 8, a light mulch of crabgrass hay and weeds was
applied to one-third of each of the rows. The mulched area of
each row received only one cultivation, while the un-mulched
parts of the rows were cultivated four times.
In harvesting, 162 hills were taken from each row, half of
these coming from the mulched and half from the un-mulched
part. A summary of the data taken is given in Table VII.


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TABLE VII.-AVERAGES OF DATA FROM THE SIX PLANTINGS OF POTATOES. THE MULCHED (M) AND NOT MULCHED AREAS
ARE COMPARED IN EACH CASE.

Row I II III IV V VI
Not Not Not Not Not Not
Treatment ............................... M M M M M M M M M M M M

Av. no. tubers to hill ...-............ 11.64 14.18 12.48 13.45 16.61 21.48 12.94 15.79 11.48 13.54 9.20 9.33

Av. wt. tubers to hill (grams).... 56.60 51.54 58.58 51.91 38.70 23.02 59.01 47.34 62.53 43.27 85.12 82.40
Percent no. 1's tubers to hill.... 29.67 25.86 26.72 23.28 12.91 4.26 29.07 18.20 33.89 26.85 56.60 47.46

Calculated no. bbls. per acre... 47.70 48.33 48.33 41.40 33.65 14.24 49.63 39.27 55.69 55.67 69.91 60.42
Av. green wt. tops (grams) ....... ........... -- ....226.85 315.74 322.53 369.51 483.68 546.60

Av. length rhizome ......- 0.84 0.49 0.73 0.72 0.69 0.56 1.16 0.87 1.11 1.06 2.12 2.04
Av. length tap-roots .. 10.57 10.76 9.70 10.36 7.69 7.20 10.94 10.01 11.29 10.83 12.42 11.41

Av. percent Moisture during
growing period ................... 7.64 7.51 7.49 7.55 7.66 7.76

Av. temperature in degrees C.
during period of tuber
growth* ..-..---------....-------. 18.6 19.4 19.0 18.6 18.0 17.2

*Time of tuber formation was during the third, fourth and fifth weeks after planting. The period of tuber growth
is therefore that time between the fifth week and the time of harvesting.
CI






Florida Agricultural Experiment Station


The following conclusions and summary seem to be justified
from the data secured from this experiment. Recommendations
to growers as to time of planting or other cultural practices are
withheld, pending a repetition of the experiment.

SUMMARY
1. Temperature is the chief weather factor involved in deter-
mining yields. Moisture is secondary and shows its chief effects
in (a) soil-temperature modification, and (b) influencing the
amount of Rhizoctonia infection. Moisture content of the soil
was the controlling factor of Rhizoctonia infection when tem-
peratures were below 20"C. Above that point, temperature was
the controlling factor.
2. Temperatures during the period of tuber growth show a
high positive correlation with average weight of tubers produced
in the successive planting. The highest yields were secured where
this temperature most closely approached 17'C.
3. Mean temperatures for the growing period of January to
May 15, over a period of 13 years, indicate that potatoes planted
in the first two weeks of January in the LaCrosse area are most
likely to develop under favorable temperatures.
4. A light straw mulch is effective in reducing soil tempera-
tures from three to five degrees Centigrade at a depth of 8.9
centimeters. This was responsible for increasing the size and
decreasing the number of potatoes per hill, the net result being
an increased number of marketable tubers.
5. The average green weight of tops per hill was greater on
the un-mulched than on the mulched rows. The soil moisture
content was less in the mulched area, indicating a higher rate of
transpiration from plants from the mulched area.
MISCELLANEOUS
Working on the hypothesis that vegetable varieties or strains
may be found that are especially adapted to the peculiar "out of
season" requirements of our Florida climate, some initial work
has been started in the selection of individual plants of the
"Iceberg" (New York or Wonderful) lettuce showing strong
heading characteristics. The heading of this type of lettuce at
the present time is very uncertain and is apparently directly re-
lated to our rather wide deviations in mean maximum and mean


58R





Annual Report, 1927


minimum temperature at critical periods in the growth of the
plants.
Bean varieties secured from the arid Western states have
been planted in different parts of Florida for two successive
years. The quality of beans and their comparative freedom from
serious seed-borne diseases (Anthracnose and bacterial blight)
show a marked improvement over the general run of seed from
miscellaneous sources. The Bountiful, Burpee's Stringless Green-
pod, Giant Stringless and Kidney Wax Round-pod have given the
most promise. The Tennessee Green-pod is the poorest variety
from the stadpoint of yield, and disease resistance.

PECAN INVESTIGATIONS
Several varieties of pecans and walnuts have been added to
the variety orchard during the fiscal year-the 11 pecans are
all promising Texas varieties that seem to be worth testing under
Florida conditions.
The walnut varieties are of the heart nut type, being seedlings
of Japanese walnuts (Juglans sieboldiana), to which names have
been given. These additions and the number of trees of each
variety are: PECANS (Hicoria pecan) : 5 Burkhart, 5 Cline,
5 Evans, 5 "E-3," 4 Golden, 1 Harbin, 5 Nuggett, 5 Seguine, 5
Sims, 5 Sovereign (Texas Prolific, Syn.), and 5 Welty; JAPA-
NESE WALNUTS (Juglans sieboldiana): 3 Bates, 3 Faust, 3
Lancaster, and 3 Ritchey.
A volunteer crop of Crotalaria striata, Crotalaria sericea and
beggarweed, amounting to 21,126 pounds per acre, green weight,
was turned into the soil in the fall of 1926, thus adding organic
material in a sufficiently large quantity to be of much assistance
in maintaining soil fertility.
Measurements of the trees in the variety orchard show that
the strong, vigorous ones at the time of planting have made the
greatest growth during the three-year period. The trees of most
of the varieties that are generally considered to be the heaviest
producers in Florida are developing the largest number of ter-
minals, which would seem to indicate that there is a direct corre-
lation between twig growth and nut production.
Several of the English Walnut (Juglans regia) trees were kill-
ed by cold injury during the past winter. It seems that they are
susceptible to injury by cold, and are often severely damaged by
great fluctuations in temperature.


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Florida Agricultural Experiment Statzon


STOCK TESTS

Measurements have been made of the seedlings growing in
the nursery, which are being tested for pecan stocks. The great-
est growth of all was made by the water hickory (Hicoria aqua-
tica), while seedling and Moneymaker nuts from the Southeast-
ern part of the United States gave the largest pecan seedlings of
those studied. Plump, well developed pecan nuts, ranging in
size of from 75 to 90 to the pound grew the most rapidly of any.
Seedling pecan nuts from Texas and those from varieties highly
susceptible to pecan scab, produced seedlings that seemed to be
more susceptible to scab than the others, and it seems that this
was one of the factors that prevented them from developing as
some of the better ones did.

FERTILIZER EXPERIMENTS
Encouraging results are being obtained with some of the fer-
tilizer experiments in nut production and tree growth. It appears
that best results are being had where the ammonia is derived,
approximately one fourth to one third from an inorganic source,
as sulphate of ammonia or nitrate of soda, and the remainder
from organic materials as cottonseed meal, or blood. Acid phos-
phate and sulphate of potash seem to be giving good results as
sources of phosphoric acid and potash respectively. The experi-
ments will require a longer period of time to give conclusive,
definite data.
REJUVENATING EXPERIMENTS
The trees in the rejuvenation experiment in Jefferson County
are making satisfactory growth. The twig development is all that
could be expected when condition at the beginning is considered.
The foliage has a good color, and the trees in general show to
be in a vigorous, thrifty condition.
There was greater gain in trunk circumference during the sec-
ond year than the first. The total average gain of all varieties
in 1925 was 0.7 centimeters, while for 1926 it was 4.8 centime-
ters. The trees in this experiment were set in 1904, except a
few planted at later dates to replace losses in transplanting.
The production of the orchard was about 500 pounds of nuts
the first year (1925), and slightly less than 1,500 pounds the
second (1926), thus giving a very decided increase.
One other rejuvenation experiment, working with compara-


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Annual Report, 1927 61R

TABLE VIII.-AVERAGE GAIN IN TRUNK CIRCUMFERENCE IN CENTIMETERS,
OF TREES IN REJUVENATION EXPERIMENT (JEFFERSON COUNTY).
Number Gain in Centimeters Gain of 1926
Variety Trees 1925 1926 Over 1925

Curtis ................... 12 0.1 5.0 4.9
Russell -..... ......... 33 2.2 4.1 1.9
Young ..................... 34 0.2 6.6 6.4
Frotscher ............ 56 0.3 4.4 4.1
Pabst ..................... 62 0.6 5.9 5.3
.Schley ..................... 79 0.3 4.3 4.0
Stuart ......... ......... 110 r 1.5 3.6 2.1

Average of all varieties ............. -0.7 4.8 4.1
tively young trees, was started during the spring of 1927 in
Clay County.
ROSETTE EXPERIMENT
The trees in the rosette experiment that are receiving the
organic materials are showing somewhat faster improvement
than the others. This experiment, however, must run a longer
period before a definite report can be made.

DISEASE CONTROL
The disease control work was turned over to the Department
of Plant Pathology, July 1, 1926, and is being conducted by R. E.
Nolen.
INSECT CONTROL
Since the Department of Entomology has employed a full-time
man to investigate pecan insects, this work has been turned over
to it and is being looked after by Fred W. Walker.
COVER CROP EXPERIMENTS
The cover crop work being conducted in cooperation with the
growers is being continued. Crotalaria sericea is promising as a
cover crop for pecan orchards. Hairy vetch has made satisfac-
tory growth as a winter crop in Bradford, Duval and Escambia
counties.
CORRESPONDENCE
Inquiries have constantly increased, and many letters have
been written giving information regarding pecan growing in
Florida.





Florida Agricultural Experiment Station


REPORT OF PLANT PATHOLOGIST

Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Plant Pathology for the fiscal year ending June 30, 1927.
Respectfully,
O. F. BURGER,
Plant Pathologist.

During the past year the Department of Plant Pathology
has been working in co-operation with the State Plant Board
on scaly-bark of citrus, citrus canker, strawberry diseases, and
diseases of coconuts. Co-operation with the office of Truck, Cot-
ton, and Forage Crop Diseases, of the United States Department
of Agriculture, has been continued on the control of tomato
nailhead rust and cause of tomato mosaic. This department took
over the work from the State Plant Board on the fungous con-
trol of the citrus aphid.
In March of this year a field laboratory was established at
Monticello for the study of pecan scab. The pecan growers of
Monticello contributed sufficient funds to get this laboratory
established. The laboratory is located in the same building with
the Chamber of Commerce.
The storm at Homestead last September completely destroyed
our laboratory. The laboratory is now located in a room at the
Homestead High School building.

CITRUS CANKER
The laboratory work in citrus canker is being carried on by
Kenneth W. Loucks. In the work this past year an effort was
made to infect young plants as they pushed up through soil
which had been previously inoculated with Bacterium citri. This
was not accomplished. It was then thought that the seedlings
might be immune. However, when young seedlings were sprayed
with a culture of Bacterium citri, they became infected. It was
again proven that Bacterium citri is unable to live in the soil
for any length of time.
Considerable time also was spent in studying the variations
of the organism in culture. Studies on the rate of growth of the
organism and the factors which are concerned in growth were
continued.


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Annual Report, 1927


MELANOSE

The melanose experiments were not so successful last year.
The October storm blew most of the fruit off the trees. Thih
spring more sprayings were made with various fungicides to
get their comparative value in controlling this disease.

SCALY BARK INVESTIGATIONS
Erdman West, Laboratory Assistant in Plant Pathology, was
in charge of scaly bark investigations. His report follows.
The study of scaly bark of citrus has been continued during
the past year, both in the field and in the laboratory. Periodic
field observations were made in several groves on the East Coast
in the vicinity of Cocoa, and also in the original scaly bark
grove on the Phillipi Hammock at Safety Harbor, near Tampa.
Isolation studies and the examination of sectioned material
have been continued at Gainesville as well as a series of inocu-
lation experiments with diseased material from the above men-
tioned groves and with organisms isolated from such material.
The field observations have served to corroborate the pre-
vious findings as to the time of appearance of the new infec-
tions, the age of the material on which these first appear and
their subsequent development. In one instance a severe infesta-
tion of typical spots was found on the leaves of the grapefruit
tree grafted on sour orange stock. There were no infections of
the stem of the grapefruit but a sucker from the sour stock
growing up through the tree was heavily infected. The grape-
fruit leaves near this sour stem showed severe infections. Evi-
dently grapefruit stems are most resistant to the disease. -
In the Phillipi Hammock, slightly more than 50 percent of
the fruit on the trees infected with scaly bark dropped, heavily
infected with the nailhead spotting. This grove has received
little attention and no spraying for several years, but is now
being cleaned up.
In the inoculation experiments, using pieces of diseased ma-
terial as a source of inoculum, no positive results have been ob-
tained. It is proposed that new plants of known susceptible an-
cestry be used in future experiments of this kind.
In the isolation studies, several strains of bacteria have been
consistently obtained by various methods. Seedling trees in the
greenhouse have been inoculated but no infections have resulted.


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Florida Agricultural Experiment Station


Work with sections of the diseased material has been contin-
ued, using in particular the alkaline methylene blue and Haiden-
hain iron alum haematoxylon stains, as these seem to give the
best differentiation in this material. No organism has been defi-
nitely demonstrated in the lesions, though many of them show
formations or structures suggesting bacteria.

IDENTIFICATION OF PATHOLOGICAL AND MYCOLOGICAL
SPECIMENS
In the past year, nearly 1,000 specimenes have been received
and examined in the laboratory. Most of these have been sent
by correspondents and the identifications and control measures
where desirable, have been returned by mail. Cultural studies
have been made in such instances as demanded it for the deter-
mination of the cause of the disease.
Stock cultures of over 200 pathogenic organisms isolated from
Florida material have been maintained.
Specimens of fungi and diseased material which were suit-
able have been preserved in herbarium packets. These, supple-
mented by collections made by members of the department lo-
cally and while on trips, have been incorporated in the Mycolo-
gical herbarium. Over 500 numbers have been added in this way
during the past year. Many of these have not hitherto been re-
ported from Florida.
Typical specimens of important diseases have been preserved
in glass museum jars and kept on display in the laboratory. This
material is increased as typical specimens are obtained.
A canker disease of roses, not previously reported from Flori-
da, has been sent in on several occasions. A species of Coniothy-
rium is the cause of the disease, .which resembles in effect the
brown canker caused by Diaporthe umbrina and seems nearly
as serious. This was identified by Miss Anna Jenkins, of the
United States Department of Agriculture.
The root rot caused by Clitocybe tabescens was found on
climbing roses and loquat, both of which are new hosts for this
trouble. It is a rather common disease of guavas in the state.

DISEASES OF THE CITRUS APHID
The work on diseases of citrus aphid was carried on by W. A.
Kuntz at Lake Alfred. The following is his report.
During the past year numerous problems with entomogenous


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Annual Report, 1927


fungi have been recognized in the field. Some of these entomo-
genous fungi have been introduced into the greenhouse where
they will be studied under controlled conditions. The major ef-
fect has been confined to the diseases of aphids, and especially to
the Empusa disease of those hosts. The present report deals
largely with field data and greenhouse experiments of this di-
sease, especially as related to the new citrus aphid.
EMPUSA FRESENII ON APHIDS
HOST RANGE AND INTER-CROPPING. From a purely the-
oretical consideration an important factor must be borne in
mind. Actual contact or a very close proximity of diseased aphids
with healthy aphids must be established in the field before the
disease-causing organism can be transmitted to healthy aphids.
From field observations this fact was well established during
the past spring. In new colonies examined in the latter part of
March of this year generally one or two diseased winged fe-
males were found. In no case has evidence been secured to es-
tablish wind as the agent of spore dissemination of this disease.
The wind may spread the causal fungus over a small area; but
from the standpoint of efficiency in causing an epidemic, this
may be considered negligible. It seems evident that the migra-
tion of the aphids is responsible for the spread of the disease
caused by Empusa fresenii over long distances.
It is not desirable to further reproduction of the new citrus
aphid (Aphis spiraecola) by any host whatsoever in the citrus
grove. The brown or black citrus aphid (Toxoptera aurantiae)
in host range is limited to citrus, olive, and a few shrubs. The
common vegetable aphid (Myzus persicae) is not severely at-
tacked under greenhouse conditions by Empusa fresenii, and
from the observations of this year in the garden this species
was not at all subject to the disease.
The general field survey conducted throughout the preceding
year has been omitted during the past year. It was felt that
too much time was spent in making casual observations in groves,
and not enough time given to the study of an epidemic of Empu-
sa fresenii in a single grove.
WEATHER CONDITIONS AND THE DISEASE. It is as-
sumed from observations on the Entomophorae that moist, foggy
but not necessarily rainy weather, is conducive to the more rapid
growth of these fungi. But in experimental work conducted in


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Florida Agricultural Experiment Station


the green house, a constant high humidity of between 80 and 90
percent tends to develop secondary mold fungi. These fungi in-
hibit spore dissemination of the Empusa by completely envelop-
ing the diseased insect. By this means the period of spore dis-
charges is shortened.
TENTED TREES. With a desire for more critical field data
during the spring of 1927 three large Valencia orange trees were
tented with cheesecloth. Briefly stated, the outline of this phase
of the project called for: (1), check of the aphids present from
the stadpoint of the elimination of Empusa by the use of this
type of screen, and (2), the introduction of Empusa on both the
new citrus aphid and the brown citrus aphid. In this latter phase
the rapidity of death for both species of aphids, as well as the
ability of crossing over a single strain of the fungus from the
new citrus to the brown aphid was to be studied.
The general handling of these tents was purely problematical
when first undertaken. Records of humidity and temperature
have been kept and are being summarized. Compared to outside
conditions the temperature shows little variation in maximum,
minimum or mean. The fluctuation is in all cases within the
limits of two degrees. In relative humidity the fluctuations, as
shown by the use of the sling psychrometer, are most appre-
ciable at noon.
In order to continue growth on these trees, so as to eliminate
frequent introduction of new colonies of aphids, three prac-
tices have been followed with all of the four trees in this ex-
periment. (1) Fertilizer was applied in small quantities at
monthly intervals. (2) Leaves were mechanically removed from
the trees. (3) The trees were irrigated for three to five hours
once or twice a week, depending upon the amount of rainfall.
GREENHOUSE CULTURES OF THE CITRUS APHID.
Throughout the winter, from late November to the present, the
new citrus aphid has been breeding in the greenhouse on citrus
and Spiraea. It may be stated that citrus has been found diffi-
cult to work with, because of the lack of continuation of growth
suitable for a colony longer than three weeks at a time. The
citrus aphid is more restless on citrus than on Spirea.
It may be pointed out that in practically all cases of cultures
of this aphid affected with the Empusa disease, there is a pe-
riod of adjustment manifested at first in the relationship of


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Annual Report, 1927


the aphid to the disease. This period may be a week but gener-
ally is from three to four weeks. In it the aphid increases more
rapidly, but later is overtaken by the diseases.
The Empusa spread rapidly until all aphids were killed on
February 26, 43 days after incubation. The new growth began
to put out and after several new leaves had been formed more
live aphids were introduced on the new growth. These aphids
did not mingle with the dead aphids on the older growth; hence
they did not become infected.

COCONUT BUD ROT
J. L. Seal was in charge of the work on Coconut bud rot. Fol-
lowing is his report:
During the past year this problem has been studied from
the field and laboratory standpoint. The disease has been re-
ported from only a very few new properties and not as common
as previously from the old infected areas. There seems to be a
more or less definite distribution along the southeastern coast
from Ft. Pierce to Homestead but more common in the areas
around Miami and Palm Beach. We find here, as reported in
other countries, that there is a definite correlation between
rainfall and outbreaks of the disease. Plants grown on low
grounds are more severely attacked than those grown on high
ground.
From laboratory studies of the various Phytophthora isolated
from but-rotted palms it was found that these organisms varied
somewhat in their morphology and physiology. In an effort to
identify them from earlier works it was found most confusing
and, in fact, impossible to make any definite determinations as
the various authors gave such varied morphological and physi-
ological characters and within these limits there might be sev-
eral distinct organisms. Phytophthora spp. known to attack
palms in this and other countries were collected as well as Phy-
tophthora terrestris, which is quite common in the area that the
palms are grown. The morphological characters of the latter
are well within the limits of those described for the organisms
attacking the palm.
When plants were inoculated with the above organisms, they
readily produced the disease and showed no symptoms that would
lead to their distinction. Laboratory methods were resorted to
and from these studies it was found that the organisms are very


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Florida Agricultural Experiment Station


closely allied and in many characters overlapping. A statistical
study of the morphological units verifies the above and indicates
that we have under consideration a composite species, the va-
rious members of which show overlapping characters that would
not justify raising them to specific rank.

CITRUS BLIGHT OR WILT, WATER INJURY, AND RE-
LATED TROUBLES

Dr. A. S. Rhoads was in charge of this work and the following
is his report:
The work of the past year on citrus blight or wilt, water in-
jury, and similar conditions has been confined largely to obser-
vations and studies of this group of closely related troubles. All
the additional studies and observations made during the past
year emphasize the definite correlation between the occurrence
of the chronic wilt and decline known as blight and the water-
holding capacity of the soil type in question.
The rainfall of the past winter and spring has been exceed-
ingly scanty and this dry period has been prolonged throughout
the early summer so that many groves on less favorable soils
suffered severely from drouth. Large numbers of affected trees
which the writer has had under observation have died or fur-
ther declined under the influence of this prolonged dry weather
and many others, previously healthy, have developed the chronic
wilt and decline known as blight.
The weather conditions during the past few months have
furnished a striking illustration of how dry weather, following
upon excessively wet periods which injure the root systems of
trees in the lower situations in the groves, very commonly accent-
uates the injury and is an important contributing factor to the
development of the chronic wilt and decline known as blight.
This was especially striking in large areas of grove on Merritts
Island that had been injured more or less by a pronounced rise
of the water table during the fall of 1926. Areas of grove in-
termediate in elevation between the low spots showing chronic
water injury and the higher elevations, in some cases exhibited
from 25 to 50 percent defoliation in April, 1927, while a con-
siderable number of trees on the margins of the intermediate
elevations bordering on the local low and chronic water-injured
spots showed defoliation varying from 75 to 100 percent at the


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Annual Report, 1927


same time. Areas of grove at sufficiently higher elevations that
they did not have the root systems of the trees injured by ex-
cessive soil moisture showed but little effect of the prolonged
drouth.
Additional observations have been made of blighted trees
during the past spring and early summer to determine their be-
havior as compared with that of normal trees. It has been found
that trees or parts of trees that are developing or have developed
the chronic wilt known as blight fail to put out a new flush of
growth at the normal time in the spring. About six or eight
weeks after the normal blooming period blighted trees develop
more or less bloom, which may or may not be followed by a
weak flush of growth, depending upon the condition of the tree.
Individual branches on affected trees may continue to bloom
sporadically until midsummer. By noting the failure of trees to
develop a new flush of growth in the spring, together with a gen-
eral dullness and lack of sheen to the foliage, it is possible to
determine whether or not trees are going to develop blight be-
fore they actually develop an appreciable wilting and curling of
the foliage.
The trees that have been budded or grafted with budwood from
various blighted trees, the oldest of which are now three years
of age, continue to show every indication of making as good
trees as the check trees budded or grafted from non-blighted
trees. Some of these trees have already borne fruit.
PSOROSIS
Investigations on psororis were begun late in the fiscal year
of 1926-27. The preliminary investigations of this disease indi-
cate that it is of more widespread occurrence and of much great-
er economic importance than gummosis. Experiments were
started in scraping and painting the psorosis lesions with va-
rious antiseptics to determine the most effective method of con-
trolling this pernicious bark disease. To date 20 grapefruit and
70 orange trees in one grove near Courtenay on Merritts Island
have been scraped and treated with Bordeaux paste and 20
grapefruit and tangerine trees in a grove on Merritts Island
have been scraped and treated with carbolineum. These cases of
psorosis varied from slight cases of comparatively recent origin
to old ones of several years' standing.
Observations of psorosis lesions painted with various prepa-


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70R


rations by growers in past years without first thoroughly scrap-
ing off the outer scaling bark indicate that this method of treat-
ment is of little or no value in checking the development of the
disease.
PECAN DISEASE WORK
Experimental work by R. E. Nolen was begun in July, 1926
for the control of pecan scab.
Experiment No. 1 was conducted in a block of Schley trees.
The trees were sprayed with different Bordeaux formulae,
namely 4-5-50, 3-4-50 and 2-3-50. The amount of scab appear-
ing on leaves and nuts was least on the trees sprayed with 4-5-50
and most on the leaves and nuts of the block of trees sprayed
with 2-3-50 Bordeaux.
Experiment No. 2 was conducted in another block of trees,
which were sprayed three times with Bordeaux mixture for
control of scab on husks. Counts showed that 26 percent of the
husks were diseased with scab.
Experiment No. 3 was conducted on Schley trees in an orchard
near Monticello in which no scab control had been attempted.
The treatments were as follows: 20-10-70 copper-arsenate-lime
dust, 20-20-60 copper-arsenate-lime dust and 95-5 sulphur-lime
dust. Three applications of each were made. The 20-10-70 dust
gave best results and the sulphur dust gave poorest results.
In all the experiments such a large percentage of the nuts
showed shuckworm injury that it was impossible to secure satis-
factory cracking results. In many cases it was impossible to
determine whether the injury was due to scab, shuckworm, or
both.
From the viewpoint of the number of varieties susceptible to
scab during the growing season, 1926 was a light scab year. The
three most susceptible varieties were badly infected. Moore
showed less infection than during previous seasons. No scab
was observed on Stuart, Success, Pabst and Moneymaker, which
are generally lightly infected. Curtis showed a lighter infection
than usual.
POTATO DISEASES
Dr. L. O. Gratz was in charge of the investigations on diseases
of the white potato and spent from July 1 to October 1 at
Arocstook Laboratory, Presque Isle, Me., studying various
phases of disease control. Florida imported 119,682 eleven-peck


Florida Agricultural Experiment Station









Annual Report, 1927


bags of seed potatoes from Aroostook County, Maine, this sea-
son, and the strategic point in disease control is in the fields
where the seed stock is grown.

TABLE IX.-EFFECTIVENESS OF SPRAYING AND DUSTING FOR THE CONTROL
OF POTATO DISEASES.
Calculated Yield Percentage
Barrels per Acre P n
Replica- Market-
tions Primes Seconds able Primes 'Seconds


Spray vs. Check

5-5-50 Bordeaux .... I

Check .... ---........-

Bbl. increase ..........-....

Percent increase .. -..

Odds* ........... ...


Dust vs. Check

**Copper-lime dust ..

Check ......................
Bbl. increase ............

Percent increase -.-.

O dds ............ .......-

Spray vs. Dust

5-5-50 Bordeaux ....

**Copper-lime dust ..I

Bbl. increase ............

Percent increase ...

Odds ....... I-


8

8


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


66.4

53.7

12.7

23.6

525:1


12 62.6 19.0

12 49.8 18.8

............... 12.8 0.2

.......-....... 25.7 1.3

............... 1110:1 1.68:1


27 I 64.4 17.7

27 61.5 17.9

............ 2.9 -0.2

............ 4.7 -1.3

.......... 7.79:1 2.26:1


82.8

71.7

11.1

15.5

103:1


81.6

68.6

13.0

19.0

1110:1


82.1

79.4

2.7

3.3

7.79:1


80.0

74.8


78.4 I

77.5 i


... ..----------- ---


*Significance is indicated by odds cf 30:1 or over.
**Copper-lime dust used contained 6.8% metallic copper or 20% mono-
hydrated copper sulphate and 80% hydrated lime.
In Table IX are the average data obtained from the spray and
dust plots.
Five applications per plot were made. Significant increases in
primes were obtained both by spraying and by dusting. Dust-
ing gave practically as good control as spraying, and the per-
centage of seconds in the undusted and unsprayed plots was
considerably greater than in the dusted or sprayed plots.


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Florida Agricultural Experiment Station


Late blight (Phytophthora infestans (Mont.) De Bary) injury
was exceptionally severe in the Florida fields this season. Drouth
and a heavy infestation of aphids further materially reduced the
yields. Southern brown rot (Bacillus solanacearum E. F. S.)
was observed throughout the potato section. Much difficulty was
encountered by the growers, first, by shipping green stock which
developed late blight in transit, and later, from southern brown
rot which could not be detected at shipping point.
The experiments in the Hastings section consisted of seed
treatment for Rhizoctonia control, spraying and dusting for late
blight control, yield and symptom studies of the spindle tuber
disease, and variety tests.
In the seed treatment experiments, corrosive sublimate, se-
mesan bel, and dipdust were compared with no treatment. In
several plots there was a slight decrease where the organic mer-
curies were used. In another plot rather significant increases
were obtained where these compounds were used. With severe
injury in some places in the state where one of the organic mer-
curies was used, and with both increases and decreases from
these materials in our experiments, further trials are necessary
before these treatments may be followed with any degree of
satisfaction.
Spindle tuber stock, selected in Maine, was planted in Florida
and compared with healthy stock of the same strain, the experi-
ment consisting of six replications. The stand was 83 percent in
the healthy stock and 35 percent in the spindle tuber stock. Many
of the seed pieces of the latter decayed within 10 days or two
weeks after planting, and in many instances before the sprouts
were through the ground. Following is the yield obtained, calcu-
lated on a basis of 100 percent stand from the actual yields ob-
tained:
Calculated Barrels per Acre Percentage
Primes Seconds Market'ble Primes Seconds

Healthy stock .......... 33.8 16.4 50.2 67.4 32.6
Spindle Tuber stock 2.9 10.1 13.0 22.4 77.6
Difference --....-- .....-- 30.9 6.3 37.2 ........ ...... ... .. -
Percent difference ... 914.0 38.6 74.1 ............ ...
Odds ................-........ 1249:1 98:1 1999:1 ..1 ................ .. ---


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Annual Report, 1927


Following is a list of the varieties tested together with the
average yields:
Calculated Barrels per
Acre Percentage






Irish Cobblers (Maine) .............. 62.4 9.3 71.7 87.0 13.0
Green Mountains (Maine) ......-- 50.6 12.7 63.3 80.0 20.0
Bliss Triumphs (Nebr.) ........... 46.5 9.1 55.6 83.6 16.4
"Bill Spud" Spauldings ........... 45.9 17.5 63.4 72.4 27.6
Spauldings (New York) .- 47.2 17.2 64.4 73.3 26.7
Spauldings (Maine) ................. 47.5 19.6 67.2 70.8 29.2

TRUCK CROP DISEASES
TOMATOES
Truck crop disease projects are being conducted by G. F.
Weber, assisted by Stacy Hawkins and David G. A. Kelbert at
the field laboratories at Homestead and Bradenton, respectively,
and two part-time student assistants at Gainesville.
The storm of September 18, 1926, totally wrecked the Home-
stead laboratory, resulting in a slight handicap in investiga-
tional work and considerable loss in laboratory equipment. The
field laboratories have been utilized almost wholly in the inves-
tigation of tomato diseases.
Nailhead Rust: Ten acres of tomatoes in the vicinity of
Homestead and seven acres in the Bradenton section were plant-
ed in experimental plots to which were applied 12 different fungi-
cides, all of them made principally of copper or sulphur. Nail-
head rust was not common. In control plots where no fungicide
was applied, less than 1 percent of infected fruit was found. The
plants to which copper fungicides were applied were consider-
ably greener and more luxuriant than check plots and sulphur
plots. There was little difference between the sulphur plots and
the check plots.
A variety plot was grown consisting of about 20 of the impor-
tant commercial varieties of tomatoes and 42 selections of Mar-


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Florida Agricultural Experiment Station


globe seed of the previous season. In these plots as a whole the
Marglobe selections were superior to the other varieties.
Wilt: Because of the dryness of the season tomato wilt was
more prominent than ever before and it was noted that Mar-
globe strains did not show more resistance to this disease than
some of the Globe selections.
Mosaic: The investigations of tomato mosaic have been con-
ducted at Bradenton, in cooperation with the U. S. Department
of Agriculture, the work being in charge of Dr. S. P. Doolittle
of the Office of Vegetable and Forage Diseases of the Bureau of
Plant Industry.
During 1927 mosaic appeared in a few fields at Bradenton,
about March 1 and between March 15 and April 15 there was an
unusually rapid dissemination of the disease, approximately
70 percent of the plants in the Bradenton section being affected
by mosaic on May 1. Experiments have shown that tomato mo-
saic is transmitted by aphids. Experiments on the transmission
of the disease by pruning indicate that considerable infection
takes place in this manner. In topping, also, where a knife is
used, a considerable increase in the amount of infection usually
occurs if mosaic plants are numerous in the field at the time.
The sources of the first infection in the field have not been
satisfactorily determined. Studies of possible wild host plants
have not as yet revealed any such host which appears to be of
importance as a source of primary infection. Trials with seed
from mosaic plants have so far confirmed the belief that the dis-
ease is not seed-borne. Studies of the soil transmission of to-
mato mosaic are in progress and have shown that the disease
may live for some weeks in the soil, but it is not as yet certain
that it survives in the soil for any extended period.
Experiments on the control of tomato mosaic through the
removal df all mosaic plants which appeared early in the season,
combined with the use of nicotine dust to reduce the dissemina-
tion of the disease by aphids, have given encouraging results.
When nicotine dust was used but no mosaic plants removed, the
percentage of infection was approximately the same as in the
check plot.
Observations have shown that the so-called "streak" disease
of tomato occurs occasionally in Florida in the field, but appar-
ently only in rare cases. Another peculiar type of mosaic has


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Annual Report, 1927


been found in the Bradenton section and studies are now in pro-
gress on both diseases.
A detailed study of the organism causing early blight of
numerous Solanaceous plants has been carried on at Gainesville.
Bulletin 185, dealing with the diseases of tomatoes in Flor-
ida, was published in December, 1926, in cooperation with G. B.
Ramsey, Associate Plant Pathologist, Office of Vegetable and
Forage Diseases, Bureau of Plant Industry, United States De-
partment of Agriculture.

CUCUMBERS
Downy mildew (Pseudoperonospora cubensis), on cucumbers
was the most important disease of this plant during the past
year. Experiments on the control of this disease were conducted
in much the same way as similar experiments during the pre-
vious season. The plots dusted with sulphur compounds showed
a better control of the disease than plots dusted or sprayed with
copper compounds.
SEED TREATMENT
About 30,000 tomato, pepper, and eggplant seed were treated
with a number of the most common seed disinfectants on the
market to determine whether or not a definite stimulation was
produced by their use. The results showed that there was no
stimulation whatever from the disinfectants.

STRAWBERRY INVESTIGATIONS
The following is a report of the work accomplished in Straw-
berry Disease Investigations for the period of 1926-27, by Dr.
A. N. Brooks:
Anthracnose: During the latter part of August and continu-
ing through September and October a disease appeared on the
runners in several different fields. The spots at first were light
brown in color and oval in shape, later turning darker to almost
black and increasing in size rapidly until they girdled the run-
ners and extended for three or four centimeters lengthwise.
Small plants, not yet rooted, were often killed at the tips of the
runners. Infected petioles or leaves were not observed. Micro-
scopical examination of the spots showed a fair abundance of
acervuli containing many conidia and numerous setae. The or-


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Florida Agricultural Experiment Station


ganism isolated was a species of Colletotrichum. Inoculation of
young runners with the organism readily produced the disease,
but infection could not be secured by inoculating young leaves
or petioles. The disease did not appear at a later date upon the
plants set for fruiting.
Root-rot: After October 1 and through the season isolated
areas in various fields were noticed in which the plants were dy-
ing. Examination of the plants showed that small knots similar
to root-knot were present on many of the affected roots. Micro-
scopic examination of such knots showed no nematodes present
but did show mycelium in abundance. Isolation in all cases gave
a species of Fusarium.
Several cases of root-knot, leaf blight (caused by Dendro-
phoma obscurans (E. & E.)), Leaf-scorch (caused by Diplocar-
pon earliana (E. & E.) Wolf), angular leaf-spot, Botrytis rot,
Rhizoctonia rot, and Rhizopus were found during the season.
VARIETY TEST
In patches of one acre each at Plant City and at Starke sev-
eral varieties of strawberries were tested with results fairly
uniform at the two locations. Briefly the results are as follows:
Of the commercial varieties tested, those failing to show any
signs of promise are Aroma, Chesapeake, Excelsior, Nick Ohmer,
Premier, and Senator Dunlap. Those showing some promise are
Muse and Stewart seedling (both of which have been found to
be identical with Missionary), Famous, and a chance seedling
from W. F. Allen of Salisbury, Maryland, which is thought by
Mr. Allen to be a cross between Chesapeake and Klondike.
SHIPPING EXPERIMENTS
Experiments dealing with diseases developing in transit were
conducted in cooperation with the American Railway Express
Company.
Moisture: One of the faults most frequently noticed at des-
tination is the moist to wet condition of'the top layer of quarts
of strawberries in the pony refrigerators. It was corrected by
use of impervious paper as a top covering.
Temperature: Pony refrigerators will maintain a sufficiently
low temperature, but do not lower the temperature of the fruit
quickly enough.


76R







Annual Report, 1927 77R

Precooling of fruit: In some instances it was found that the
fruit was packed in the refrigerator which was then immediately
iced and closed, causing a sweating to take place and consequent-
ly the fruit treated thus arrived at destination in poor condition.
Fruit precooled arrived at the destination in better condition
than that treated as previously described.
Washing of fruit: Recommendations consisting of sanitary
practices were made in relation to packing of fruit in boxes and
pony refrigerators.







Florida Agricultural Experiment Station


REPORT OF VETERINARIAN
Wilmon Newell, Director.
SIR: I submit the following report for the Veterinary De-
partment for the fiscal year ending June 30, 1927.
Respectfully,
A. L. SHEALY,
Veterinarian.

Work was carried out during the past year on the two major
projects of this department, "salt sickness" in cattle and Man-
son's eye worm of poultry. Further studies were made on
"leeches" in horses. A new project, a study of the life history of
the kidney worm (Stephanurus dentatus) of swine, was added
to the work of this department during the year.

"SALT SICKNESS"
The work on "salt sickness" was carried out entirely on the
farms on which these cases occurred. One farm located in Levy
County had a total of four typical cases of this disease. All four
cows were greatly emaciated, unthrifty and very weak. These
cows had shown symptoms of "salt sickness" for a period vary-
ing from three to eighteen months prior to the beginning of the
experiment. A careful examination was made for evidence of in-
testinal parasites, and the blood of each animal was examined
for detection of any pathogenic organisms which might be pres-
ent. All such examinations proved negative.
Upon inquiry it was found that these cattle had not been fed
a balanced ration for several months, their ration being too high
in carbohydrates and too low in protein. After feeding these ani-
mals a well balanced ration, which included a small amount of
precipitated bone meal, for a period of 10 weeks, all four of the
affected cows had apparently recovered from the diseased con-
dition. Two additional cases were treated in the same manner
on other farms, and the results were identical. These two cows
also gave negative findings for intestinal parasites and patho-
genic organisms.
Another case of unusual interest occurred in one of the best
dairy herds in the southern part of the state. The owner of this
herd stated that he had lost a few of his best cows within the
past two years from a mysterious disease which he called "salt


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Annual Report, 1927


sickness." A post mortem examination was held upon one cow
that showed symptoms of the peculiar disorder, and in the course
of this examination, lesions suggestive of paratuberculosis
(Johne's disease) were found. Specimens were brought to the
Station laboratory and, upon a microscopical examination, organ-
isms typical of Bacillus paratuberculosis were observed. A re-
port of the post mortem examination and laboratory findings
was made to the federal inspector in charge of tuberculosis
eradication work in this state. This official visited the farm a
few weeks later and applied the johnin test (for paratuber-
culosis or Johne's disease) to another similarly affected cow. The
test gave a positive reaction for paratuberculosis.
It will be seen from these observations that the livestock
owners designate practically any condition in which the cattle
become emaciated and unthrifty as "salt sickness." There are un-
questionably many different causes for the diseased condition
called "salt sickness"; however, judging from the results of
experiments conducted thus far and from field observations it
seems that this ailment is due chiefly to a nutritional disorder
resulting from the feeding of an unbalanced ration and possibly
to a lack of calcium and phosphorus.

MANSON'S EYE WORM OF POULTRY
The entire work on Manson's eye worm has been done by Dr.
D. A. Sanders, assistant veterinarian.
Further studies were made on the life history of Manson's
eye worm. Taking into consideration the results obtained from
previous experiments conducted on the life history of the eye-
worm, it appeared quite evident that the life cycle included an
intermediate host. Examinations were made upon many insects
and external parasites which are commonly found on poultry
and around the premises of poultry flocks in an effort to find
the probable intermediate host.
In this search for the intermediate host specimens of a cock-
roach Pycnoscelus surinamensis (Linn.) were found and upon
examination, cysts containing larvae of a nematode were detect-
ed within the body cavities of this roach. These larvae resembled
the larvae of Manson's eye worm in every respect. Several
roaches of this species were dissected, and the larvae obtained
thereby were placed in the eyes of chickens with the result that
these larvae remained within the eyes and produced infestation.


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Florida Agricultural Experiment Station


Some of these larvae were placed in the mouths of chickens, and
shortly thereafter the larvae were detected within the eyes of
birds thus infested. Several chickens were fed partially dissected
and whole roaches with the result that infestation was produced
in every case. The larvae were then identified as Manson's eye
worm, and it was proven from these experiments that the spe-
cies of cockroach, Pycnoscelus surinamensis (Linn.) is an inter-
mediate host for this parasite.
Experiments conducted by feeding whole roaches revealed the
fact that the larvae are liberated from the roach when the roach
reaches the crop of the chicken. After leaving the roach, the
parasites then quickly work their way up the oesophagus to the
mouth and thence up the naso-lacrimal ducts to the eyes of the
chickens. Infestation has been produced in the eyes of non-in-
fested chickens in 20 minutes after feeding these chickens whole
roaches.
In order to determine the distribution of the larvae after a
chicken has been fed whole roaches, the following experiment
was conducted. A noninfested chicken was starved for 18 hours
and then allowed to eat four live roaches, followed by a small
amount of mash and water. Forty minutes later a post mortem
examination was made upon this bird and eyeworms were re-
covered from the following organs in the numbers indicated:


No. of
Organ I Parasites
Gizzard .-- ...--....... 43
Proventriculus (glanular
section of stomach) .. 2
Second portion of oesoph-
agus .-------..----- ............ 1
C rop -....-...--..-. --- ...............- 15
First portion of oesoph-
agus ......................----.....--- 3
Trachea ......---....................... 1
Right eye ..-------. ..-.....- -- 14
Left eye .-------------........... 12


Condition of Parasites

Dead and partly broken.

4.5 mm. to 9 mm. long.

9 mm. long.
All alive and varying in length.

8.5 mm. to 9 mm. long.
9 mm. long.
8.5 mm. to 9 mm. long.
8.5 mm. to 9 mm. long.


It will be seen from the above experiment that larvae passing
through the crop to the gizzard are macerated and killed by the


80R




Annual Report, 1927


muscular action of this organ and from the grit which it nor-
mally contains. Also, it will be observed that the larvae that
reach the eye are 8 mm. or more in length. Larvae of this length
are apparently the infective stage of the parasite, for smaller
larvae do not remain in the eye even though they are placed
therein.
It is possible to infest wild birds with Manson's eye worm by
feeding these birds on roaches containing the larvae of the para-
site. The following birds have been infested in this manner: blue
jay, meadow lark, rice bird, mocking bird, and blackbird. The
pigeon will also become infested if fed infested roaches.

"LEECHES" IN HORSES
"Leeches" is a disease in horses which occurs most frequently
during the rainy season of the summer months and in the fall
of the year. Several cases were examined during the past year,
and attempts to isolate a specific causative organism for this
disease were carried out. Three different fungi were isolated
from the "kunkurs" or granules which occur in the lesions of
this disease, but it was impossible to produce the disease when
these organisms in pure cultures were injected into susceptible
animals. Examinations were made to detect the presence of a
nematode, Filaria irritans, as being a possible causative agent,
since this parasite has been detected in sores somewhat similar
to the lesions of "leeches"; but these observations were negative
for the parasite. Further efforts to isolate a causative organism,
and a more extensive study of the pathology of this disease will
be made.

KIDNEY WORM (Stephanurus dentatus) OF SWINE
The study of the kidney worm is a new project added to the
work of this department during the past year.
Several post mortem examinations have been made on swine
that died of kidney worm infestation. As a result of these post
mortem examinations the following information was obtained:
In the infested animals the parasites are found most abundantly
in the region of the kidneys, and along the course of the ureters-
the tubes which lead from the kidneys to the bladder. They are
often present in other portions of the body including the lungs,
pleural cavities, diaphragm, liver, kidneys, spinal canal, perito-
neal cavity and sublumbar muscles. The presence of the para-


81R




Florida Agricultural Experiment Station


sites gives rise to numerous parasitic cysts and abscess forma-
tions, varying in size from 0.5 to 4.0 cm. in diameter. Within
these cysts are usually found a male and a female kidney worm,
although the presence of four or five parasites have been detect-
ed in the same cyst. The parasites are found within the recently
formed abscesses, but not in old formations. The cysts oc-
curring along the course of the ureter are connected with this
organ by means of small canals or fistulous tracts. Apparently
the eggs of the parasite pass along the course of the fistulous
tracts and upon reaching the ureter they are carried down to
the bladder by the urine. Later they pass out with the urine.
There is no perceptible systemic disturbance noted in animals
harboring but few of the parasites. Infestation can be detected,
however, in such cases by making a micrscopical examination of
the urine, since the eggs of the parasite may be found in the
urine of an infested animal even though the animal is only
slightly infested and shows no symptoms of the disease.
Paralysis of the hind quarters occurs in many cases of ad-
vanced kidney worm infestation. In two cases the parasite was
found within the spinal canal. It seems highly probable that the
parasite within the spinal canal is the cause of the paralytic con-
dition in many cases.
The kidney worm is of considerable economic importance,
since this parasite attacks the hogs of breeding age and thereby
interferes materially with the future development of the herd.

DIAGNOSTIC WORK

In addition to the research work carried out on the various
projects mentioned, this department has conducted a diagnostic
laboratory for the examination of diseased animal specimens.
During the year, specimens were examined and a diagnosis
rendered as listed below:
Contagious abortion in cattle, 323 blood samples.
Fecal examinations, 12.
Texas fever, 3.
Kidney worms, 11.
Milk for pathogenic bacteria, 7.
Blood for hemorrhagic septicemia, 15.
Ascaris in swine, 3.
Swine plague, 1.
Necrotic enteritis in swine, 1.


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Annual Report, 1927


83R


The following examinations were made for diseases in poul-


Fowl cholera, 8.
Intestinal parasites, 23.
External parasites, 5.
Coccidiosis, 27.
Bacillary white diarrhea, 8.
Catarrh of crop, 2.
Egg bound, 2.
Sod disease, 2.
Roup, 12.
Chicken pox, 10.


Bumblefoot, 2.
Vent gleet, 1.
Fowl typhoid, 4.
Paralysis of domestic fowl, 10.
Leukemia, 6.
Gout, 1.
Scaly-leg, 2.
Tuberculosis, 4.
Chemical poisoning, 2.
Manson's eye worm, 25.


Many inquiries regarding diseases of livestock have been re-
ceived through correspondence during the year, and replies have
been made to these inquiries by this department.
This department has also rendered considerable veterinary
service to animals on the State Farm at Raiford.







Florida Agricultural Experiment Station


REPORT OF AGRICULTURAL ECONOMIST

Wilmon Newell, Director.
SIR: I submit the following report of the Department of Agri-
cultural Economics for the fiscal year ending June 30, 1927.
Respectfully,
C. V. NOBLE,
Agricultural Economist.


The work for the year has been a continuation of the three
projects reported as in progress for the previous fiscal year. In
addition to the above, a project was started to study the costs of
transportation of Florida citrus fruits, and to compare these
costs with those from other citrus areas.

HASTINGS IRISH POTATO AREA

Progress in the analysis and interpretation of the 294 sur-
vey records of Irish Potato Farms in the Hastings Area has
been made and the data will soon be in shape for presentation
to the publications committee. Tables and charts thought neces-
sary for a clear presentation of the data have been prepared.
The text of the bulletin has been written and criticised, and is
now being revised. This work is in charge of Bruce McKinley.

COSTS OF PICKING, HAULING AND PACKING FLORIDA
CITRUS FRUITS

As stated in the previous annual report, data from 100 Florida
citrus packinghouses were obtained covering the costs of pick-
ing, hauling, and packing Florida citrus fruits for the 1924-1925
crop. During the year just ended, similar data were obtained
covering the 1925-1926 crop. This study is in charge of H. G.
Hamilton. On October 1, 1926, Mr. Hamilton obtained leave of
absence from the University of Florida in order to pursue gradu-
ate study at Cornell University. The packinghouse cost data have
been accepted by the Cornell University Graduate School as
suitable material for Mr. Hamilton's major thesis. Progress has
been made in the checking and tabulating of the data. A brief,
preliminary statement of the results of the study will be pre-
pared and returned to the packinghouses who gave the infor-
mation immediately upon Mr. Hamilton's return to Florida in


84R









Annual Report, 1927 85R

August, 1927. It is hoped that the completed manuscript will be
ready before the end of the next fiscal year.

JACKSON COUNTY, FLORIDA, AGRICULTURAL SURVEY

The beginning of the field work of a farm management sur-
vey in Jackson County, Florida, was noted in the last annual re-
port. The field work was completed in September, 1926. After
the farm records had been carefully checked, it was found that
there were 499 which were satisfactory for use in the study
of this general farming region. Some idea as to the diversity
of farming in this county may be gathered from the following
list showing the percent of sales receipts from each class of farm
products from the 499 farms in 1925 where the sales amounted
to 1 percent or more:
Crop Percent
Cotton and cottonseed .....- .. .....-........... .. ......... ...... 41
Peanuts ............. .......... ... .......--- ..... .... ............ 26
W watermelons ....- ......... .. ........ .... ...-- ...... ...... .. 9
C orn ..... ........~...... .... ...... ..... .-- ........- ....... .... .............. 6
H og s ....... .......... .. ..- .. ...... .. ..- ...- .......... --............ ........ 6
Sugar cane (syrup) ... .............. ...... ..................... .......... 5
Cattle and cattle products (milk, butter and cream) ......... 3
Poultry and eggs ...-........-. ....2...... ...- ... -.......... ........ 2
Tobacco .... ........ ...... ... ...-.-..-...........-.. ............ 1
Sweet potatoes ...................... ....... 1

The above list does not give the relative importance of the
different products because a large proportion of such products
as corn, hogs, cane syrup, cattle products, poultry and eggs, and
sweet potatoes was used directly by the farm families for food.
Many other products were of major importance on some farms;
such as cucumbers for pickling, green vegetables and fresh
fruits for nearby markets, wood and forest products.
All major tabulations of the Jackson County records have been
made and the work of interpreting the data is in progress at
present.

COSTS OF TRANSPORTATION OF FLORIDA CITRUS
FRUITS

The costs of transportation of Florida citrus fruits project was
started as the second step in the economic analysis of market-
ing Florida citrus fruits. M. A. Brooker, who is in charge of this
work, makes the following progress report:
Only preliminary work has been done as yet on the Citrus








86R Florida Agricultural Experiment Station

Transportation project. Comparisons have been made of the
numbers of bearing and non-bearing citrus trees in Florida,
Alabama, Louisiana, Mississippi, Texas, Arizona, and California,
and an effort has been made to study the history of the industry
in each of these areas. Complete yearly statistics of the ship-
ments of citrus fruits from the beginning of the industry have
been secured from Florida, Alabama, Texas and California. An
effort is being made to secure these statistics from the other
areas. Considerable work has been done toward outlining meth-
ods for further study of the project.





Annual Report, 1927


REPORT OF LIBRARIAN

Wilmon Newell, Director.
SIR: I submit the following report of the Library for the
fiscal year ending June 30, 1927.
Respectfully,
IDA KEELING CRESAP,
Librarian.


This library is maintained to make available to the staff of
the Experiment Station and Agricultural Extension Division,
and faculty and students of the College of Agriculture, litera-
ture dealing with agriculture and the related sciences. In order
to accomplish this, merely securing material only partially ful-
fills the requirement. Bibliographies, indexes and catalogs must
be maintained or literature loses much of its value. As the library
is almost entirely for research work the nature of its contents
is necessarily largely scientific and technical, which calls for
the utmost care in the selection of material to suit the require-
ments of its patrons. Special attention has been given during the
past year to a study of the required literature, which for this in-
stitution must cover a broad range of subjects to fit the particu-
lar geographic location of Florida.
A notable increase in the use of the library has resulted through
the accession of valuable works and the maintenance of easily
accessible card catalogs and indexes. Several important bibliog-
raphies have been added while 7,200 new titles were compiled
and added to the card catalog. Of this number 6,406 have been
made in the library; the remaining 794 were purchased.
Indexing literature is a slow process. With the half-time as-
sistance available this has to be limited and confined to a defi-
nite schedule. Each day's incoming material in the form of
bulletins, circulars, and the like, has both subject and author
cards made before the material is shelved. This is not done for
the publications indexed by the Library of Congress. As this
work is completed, cataloging the literature of the various Sta-
tions is carried on beginning with the first bulletin and bringing
it to date.
There are now 5,520 bound volumes on the shelves. Of these,
520 volumes represent the additions for the year, while 256 of
these were prepared and sent to the bindery for binding. It has


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Florida Agricultural Experiment Station


been impossible to keep a record of the number of bulletins,
pamphlets and miscellaneous unbound material received. This
has all been properly arranged and filed on the shelves. A
large number of volumes have been prepared for the bindery
for the various departments also.
With very few exceptions every request for a reference ar-
ticle has been fulfilled. Through the courtesy of the Library of
the United States Department of Agriculture and Library of
Congress, what cannot be supplied here may be borrowed. In
this way practically everything that is available, from any of
these sources, may be and is secured for the workers.
The work for the latter part of the year has been hampered
by the congested condition of the present quarters. Shelf, table
and floor space are practically exhausted. With the prospect of
removal to the new quarters in the Horticultural Building, tem-
porary relief from this condition is being anticipated.
With the growth of the institution, the library has grown and
must continue to grow. The routine work of each day has in-
creased correspondingly. The accomplishments for the year have
been possible only through the attitude of cooperation on the
part of the patrons of the library.


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Annual Report, 1927


REPORT OF HOME ECONOMIST

Wilmon Newell, Director.
SIR: I submit the following report of the Home Economics
Research Department for the fiscal year ending June 30, 1927.
Respectfully,
OUIDA DAVIS ABBOTT,
Home Economist.


The work of the Department for the year has been a continua-
tion of the projects reported in 1926. A biological laboratory
has been equipped and on October 1, 1926, Dr. L. W. Gaddum
came to take charge of the biochemical laboratory.

VITAMIN A

A study of the effect of intensity and time of illumination on
the formation of vitamin A in alfalfa plants has been continued.
Alfalfa seedlings grown in the light and others grown in the
dark were dried and fed to albino rats that were on a vitamin
A-free diet. This diet was prepared according to Sherman's
method and consisted of the following:
Casein ............................ ........... ...- ---- -- 20%
D extrin .. ...................... .....-- .. .-- .-- -----. 70%
Yeast ..... ....... ..... ........ .--. .. ----- 5%
Salt m mixture ........................... -..........-.. .-- ---- 4%
N aCl .........................................- ------ 1 part
This experiment has been repeated twice.
The results seem to indicate that germinated alfalfa seed, al-
falfa seedlings grown in the dark, and alfalfa seedlings grown in
the light are effective in promoting growth and preventing
xerophthalmia when fed at the rate of 0.1 gr. per day to albino
rats on a vitamin A-free diet. These results are in accord with
those of Coward, who found that five etiolated wheat seedlings
definitely cured xerophthalmia and brought about very marked
resumption of growth, provided the basal ration was irradiated
sufficiently to supply vitamin D. In the work done at this sta-
tion the basal ration has not been irradiated, as it was thought
that the rats received enough vitamin D from the sunlight. The
experiment is being repeated, using an irradiated basal ration.
Complete dissections have been made of animals fed on ex-
perimental diets. These dissections have shown marked anatom-


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Florida Agricultural Experiment Station


ical abnormalities as (1) gastric ulcers, (2) degeneration of
the mesentery and (3) pus in the foramen cecum and inner ear.
Histological sections have been made of the tissue of the ex-
perimental rats to compare the tissues of rats fed on a complete
diet with those fed on a deficient diet.
The effect of lack of minerals on the formation of vitamin A
in alfalfa is now being considered.

NUTRITIONAL SURVEY

The survey to determine the nutritional status of children be-
tween the ages of 6 and 16 years has been continued. Three coun-
ties have now been surveyed with the following results:


Percent Percent
No. Children Under Diseased
Examined Weight Tonsils

County No. 1
144 66 58
County No. 2
322 40 36
County No. 3
247 75 43

From the food lists submitted
following data were obtained:


County


No. 1
No. 2
No. 3
Data not in.


Percent
Eye Percent Percent
Diseases Caries Hookworm


18

.07

48


All
Treated


for 6 consecutive meals the


Percent Using Percent Using Percent Using
Milk Butter Fruit

61 35 51
2.7 1.3 27

1


Percent Using
Vegetables

72
63


County No. 1 is representative of a general farming and
trucking section on the northern limit of the citrus section where
the percentage of tenancy is comparatively low. The staple crops
are corn, tobacco, peanuts and velvet beans; the principal truck
crops are cucumbers, cabbage, potatoes, lettuce and watermel-
ons; the fruits are oranges, grapefruit, strawberries and black-
berries.
County No. 2 is representative of a fruit growing and truck-
ing section lying wholly within the citrus section where the


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Annual Report, 1927


percentage of tenancy is low. The staple crops are of minor im-
portance in this county. The principal crops are citrus fruits,
strawberries, tomatoes, celery, spinach and lettuce.
County No. 3 is representative of a general farming section
where the percentage of tenancy is very high. The staple crops
are corn, tobacco, soybeans and peanuts. The only truck crop
is watermelons.
The food lists submitted from County No. 3 show the diet to
be low in Irish potatoes, milk, butter, leafy vegetables and
fruit, and high in meat, cowpeas, rice, grits and syrup.
The survey will be extended into two additional counties.

SOME FACTORS THAT INFLUENCE JELLYING

The work on the jellying properties of kumquats has been
continued. An electro-dialysis method of preparing pectin has
been used and some relatively pure pectin has been prepared.
On account of the freeze in January it was impossible to continue
work on kumquats. Work on other fruits will be in progress as
soon as the fruits are available.

CANNING OF NON-ACID VEGETABLES
In an effort to determine the cause of spoilage of non-acid
vegetables in the South, two methods have been used;
1. Vegetables canned at this laboratory in a pressure cooker
according to the directions sent out by the Bureau of Home
Economics.
2. Vegetables canned in the homes in pressure cookers ac-
cording to methods in general use. Spoiled products sent to this
laboratory.
Examinations are made to determine whether spoilage is due
to leakage or underprocessing. By the use of a pressure cooker
the organisms are limited to spore-forming types.
Examinations of products canned in this laboratory have
shown that spoilage is caused by leakage due to poor rubbers.
This loss is less than 2 percent. There has been no spoilage due
to underprocessing.
Examination of products sent to this laboratory has shown
that much of the spoilage is caused by leakage. Some jars, how-
ever, have spoiled due to flat sour organisms. These are rod-
shaped organisms that grow in short chains on plain or dextrose
agar. Work is being continued on these organisms.


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92R Florida Agricultural Experiment Station

REPORT OF THE CITRUS EXPERIMENT STATION
Wilmon Newell, Director.
SIR: I submit the following report of the Citrus Experiment
Station at Lake Alfred, for the fiscal year ending June 30, 1927.
Respectfully,
JOHN H. JEFFERIES,
Superintendent.

During the year just closed very satisfactory progress has
been made in the work of the Station. Field operations, in con-
nection with the projects under way, have been carefully super-
vised and field notes and records of the progress of the work
have been made, as in the past.
BUILDINGS AND IMPROVEMENTS
Aside from the investigational work under way, material ad-
ditions to the permanent equipment of the Station were made
during the year. In July, 1926, a modern greenhouse, 96 feet by
20 feet, with three compartments, was completed at a cost of
$5,000. The central compartment is used for propagation work
and the end compartments for Pathological and Entomological
research work.



1


Fig. 4.-New greenhouse at the Citrus Experiment Station,
Lake Alfred, Fla





Annual Report., 1927


A laboratory building was commenced in August, 1926 and
completed during the year at a cost of $12,357.00. It is a substan-
tial building, the basement being of solid concrete to the ground
line with four basement rooms, the upstairs of tiled walls with
four laboratory rooms well lighted and fitted with a heat line and
pipes for gas. The north side of the building has a temporary wall
which will be removed, when funds are available for the addi-
tion of an auditorium, which is to be 25 feet by 60 feet.
Because of insufficient funds, the basement rooms have been
left in an unfinished condition for the present.
















Fig. 5.-New laboratory building at the Citrus Experiment Station.
Among other improvements at the Station, mention should be
made of the extension of sand-clay roads throughout the groves
and around the buildings.
DIEBACK GROVE

The dieback grove has been carried on in its regular system of
cultivation and fertilization for dieback study. It is divided into
15 plots which receive various fertilizers. A good crop of fruit
was produced this year. It was weighed from each tree and
samples from the 15 plots were sent to the Chemistry Depart-
ment for chemical analysis.

HIGH AND LOW POTASH GROVE NO. 1

This grove has produced a very good crop of fruit. It was fer-
tilized and cultivated systematically. Records of the production


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Florida Agricultural Experiment Station


and quality of the fruit from each plot were made. Some of the
fruit from the high and low percent potash plots were taken to
the State Horticulture Meeting for inspection and sampling. It
was very difficult to make any distinction in the quality of the
fruit from the 5 percent and 10 percent high grade sulphate
of potash plots.

POTASH EXPERIMENT NO. 2
This grove was set in February, 1925, the object being to de-
termine the value of different forms and combinations of potash.
The experiment is laid out as follows:
Plot 1, high grade sulphate of potash three times a year.
Plot 2, muriate of potash three times a year.
Plot 3, sulphate of potash-magnesia three times a year.
Plot 4, muriate of potash one time and high grade sulphate of
potash twice a year.
Plot 5, muriate of potash twice and high grade sulphate of
potash once a year.
Plot 6, muriate of potash twice and sulphate of potash-mag-
nesia once a year.
The growth of these trees has been good and very interesting
results are expected when they come into production.

NEW FERTILIZER EXPERIMENT
The new fertilizer experiment is in cooperation with the U. S..
Department of Agriculture. Due to the Citrus Experiment Station
having all of its citrus land occupied by experimental groves it
was necessary to secure the use of a grove adjacent to the station
for this work. The object of the experiment is to test out some
different forms of concentrated fertilizers.

PATHOLOGICAL GROVE
This one acre grove was planted in January, 1926, for use in
pathology research work. It consists of a collection of rootstocks
as follows: Citrus trifoliata, Willowleaf sour orange, sour orange,
bittersweet, Cleopatra mandarin, sweet seedling, and rough
lemon.
These are budded to standard varieties of citrus, Myers Chi-
nese Lemon and a few crosses. There are four trees at the end
of each row left unbudded for stock trees.


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Annual Report, 1927


This grove is serving a double purpose by furnishing a com-
parison of standard varieties of citrus on different rootstocks, as
well as for the pathological work.

CONTROLLING JUNE BLOOM BY IRRIGATION
Six acres were cleared in 1923-24 and sowed to velvet beans in
the summer of 1924. It is divided into three plots which are
adjacent to each other, known as I-1, 1-2, 1-3. Each plot has been
planted to Marsh Seedless, Duncan, Walters and Excelsior grape-
fruit. It will be necessary to wait until the trees are older before
experimental work can be done.
This is merely a preliminary report of the experiment, just
to show that the groves have been started for this work. A
later report will show the various systems of cultivation, irriga-
tion, and cover crops.

GROVES FOR CULTURAL EXPERIMENTS
HAMMOCK CONDITION VERSUS INTENSIVE AND MODIFIED
CULTIVATION
F-l, the hammock block, contains four acres cleared of all
trees except pines. It consists of two acres of Pineapple or-
anges and two acres of Excelsior grapefruit which were planted
in 1925 by grubbing just enough ground to prepare to set the
trees. All native grasses and other vegetation is allowed to grow
but is mowed before going to seed.

MODIFIED CULTIVATION (SHALLOW CULTIVATION WITH COVER
CROPS)
F-2-This grove consists of one acre which is adjacent to F-1.
One-half acre is planted to Pineapple oranges and one-half acre
to Excelsior grapefruit. The ground is not plowed, but is har-
rowed to a depth of three to four inches. Cover crops are planted
summer and winter and disked in when matured.

INTENSIVE CULTIVATION
F-3-This plot consists of four acres, two planted to Pineapple
oranges and two to Excelsior grapefruit. The land was plowed
and with no other preparation the trees were planted immedi-
ately.


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Florida Agricultural Experiment Station


THOROUGH PREPARATION VERSUS IMMEDIATE PLANTING
In 1924 two acres were plowed and sowed to velvet beans. The
following year they were planted to Pineapple oranges and Ex-
celsior grapefruit, one acre each, to be compared with plot F-3.
This plot was designated G-1.
A two acre plot was sowed to oats in 1924, cowpeas in 1925,
and planted to Pineapple oranges and Excelsior grapefruit the
following year, (one acre each). This is plot G-2. The trees used
were the same size and age as those planted one year previously
on plot G-1. It received the same cultivation and fertilization as
plots F-3, and G-l, also given the same fertilizer the first year
as was given the other plots. This gives a comparison with other
plots immediately planted without cover crops.













Fig. 6.-View of the Citrus Experiment Station from the water tower.
WINTER HAVEN ORANGE FESTIVAL

The Citrus Experiment Station made an educational exhibit
at the Orange Festival which was held at Winter Haven January
19-21. The exhibits consisted of specimens showing different
systems of propagation, also a collection of varieties of citrus
fruits and rootstocks. The Pathologist and Entomologist also
made some very interesting exhibits of fungi and insects pertain-
ing to the citrus industry.

AGRONOMY EXPERIMENTS
COVER CROPS
The citrus cover crop experiment as outlined in the previous
annual report has been very satisfactorily continued. Crotalaria
striata yielded the highest amount of air-dry material to turn


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Annual Report, 1927


back to the land for soil improvement. It yielded 2.76 tons per
acre. It was followed by beggarweed, velvet beans, and cowpeas
in the order named, the tonnage of air-dry material per acre be-
ing 1.78, 1.53, and 1.01, respectively.
No material difference is yet noted in the citrus trees of
the blocks where the various cover crops have been grown and
turned under; however, there appeared to be some dieback in
the clean cultivated block of citrus trees being carried as a
check.
GRASSES AND LEGUMES
Centipede grass (Eremochloa ophiuroides (Munro) Hack.)
continues promising for lawns, while Bahia grass (Paspalum no-
tatum Fluegge) shows promise as a permanent pasture grass.
For a crop to cut and feed green to cows, work stock, and poul-
try, Napier grass (Pennisetum purpureum Schum.) has been
outstanding.
Molasses grass (Melinis minutiflora Beauv.) did well, but
seeded late. Further observations are being made.
Crotalaria striata Schrank, originally planted in 1924, contin-
ued to grow until January, 1927, when it was killed by cold. Af-
ter the killing of the original planting the dead plants were re-
moved and one-half the area disked and one-half not disked. An
excellent volunteer crop came back on the disked area while only
a fair to poor crop came back on the undisked area.

ACKNOWLEDGMENTS
Mr. N. H. Horton of Lake Alfred has kindly turned over to
the Experiment Station some Temple orange trees on rough
lemon root that have been inarched to Cleopatra mandarin. It is
'hoped that this will offset the influence of the rough lemon.
Mr. John Morley of Lake Alfred has permitted the Experiment
Station to use a number of Temple orange trees on the McKay
estate. These are to be transferred from the rough lemon root
to their own by the semi-girdling process just above the union.
Messrs. Perrin and Thompson of Florence Villa, Fla., have
turned over to the Experiment Station a very large Pink Shad-
dock tree for top-working into the following varieties: Tanger-
ine, King orange, Temple orange, Valencia orange, and Duncan
grapefruit.


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Florida Agricultural Experiment Station


REPORT OF THE TOBACCO EXPERIMENT STATION

Wilmon Newell, Director.
SIR: I submit the following report of the Tobacco Experi-
ment Station at Quincy, for the fiscal year ending June 30, 1927.
Respectfully,
W. B. TISDALE,
Plant-Pathologist, In Charge Tobacco Investigations.

A tobacco packinghouse, 30 by 60 feet, was erected at a cost of
$5,186.22, exclusive of equipment. Equipment is now being add-
ed so that this year's crop of tobacco can be packed in the build-
ing.
Two acres of slat or lath shade was constructed during the
year, but no tobacco was grown under the shade. It is planned to
resume the fertilizer experiments under this shade next year,
using one of the strains of tobacco most resistant to black shank.

TOBACCO DISEASE INVESTIGATIONS
BLACK SHANK
The work with black shank has been a continuation of field
trials for resistance of different selections and different genera-
tions of hybrids of several types of cigar wrapper tobacco. Five
acres of land, all thoroughly infested with the parasite (Phytoph-
thora nicotianae Breda de Haan), were used for these trials.
Two of the five acres were on the station farm. The other three,
two acres in one field, and one in another, were located in dif-
ferent sections of Gadsden County, each being about eight miles
from Quincy. Each of the three plots was located on a different
type of soil and each had been planted previously to tobacco
two or more years.
Examination of the roots of plants in the three fields showed
different degrees of nematode infestation. There was much less
injury from this parasite in the field which had been planted to
tobacco only two years. Also, a lower percentage of black shank
developed in certain strains of tobacco in this field. Certain se-
lections and hybrid strains were from 90 to 98 percent resistant
to black shank, whereas in the other fields where the soil was
more thoroughly infested with nematode, the same strains of to-
bacco proved from 5 to 10 percent less resistant to black shank.


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Annual Report, 1927


Similar results have been noted in previous years. However, the
check rows of Connecticut Round Tip developed 100 percent
black shank in all three fields. Figures 7 and 8 show the con-
trast between the Round Tip and resistant strains.





















Fig. 7.-Resistant Big Cuba in tobacco trials on Phytophthora-sick land in
1927. P-27-5 at right, an F5 selection of Big Cuba showing almost
complete stand. Connecticut Round Tip in center, all killed by black
shank. 201-2-1-5 left, an F4 selection from a cross between two types
of Big Cuba.
Certain selections from different hybrids made a very remark-
able showing this year for both resistance and quality (fig. 3).
Others were equally resistant, but the quality or leaf type or both
were not so good.
In addition to these trials of numerous strains, stock seed of
four types were given to growers for commercial trial. Each of
these types was planted on soil infested with the black shank
fungus and all strains of tobacco proved highly resistant. Most
of the types were planted early and reached the blossom stage
with very little rain. Although practically all the leaves were
harvested, they were severely affected by dry weather so that
little information has been obtained of their possibilities for
quality under normal conditions.
In 1926 several different types of partially resistant tobacco
were crossed with each other (nine crosses in all) and 10 F1


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