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Group Title: Florida Agricultural Experiment station, report for the fiscal year ending June 30th.
Title: Report for the fiscal year ending June 30th
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Permanent Link: http://ufdc.ufl.edu/UF00005173/00017
 Material Information
Title: Report for the fiscal year ending June 30th
Physical Description: 40 v. : ill. ; 23 cm.
Language: English
Creator: University of Florida -- Agricultural Experiment Station
Publisher: University of Florida
Place of Publication: Gainesville Fla
Publication Date: 1918
Copyright Date: 1905
Frequency: annual
regular
 Subjects
Subject: Agriculture -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
 Notes
Statement of Responsibility: Florida Agricultural Experiment Station.
Dates or Sequential Designation: 1905-1930.
 Record Information
Bibliographic ID: UF00005173
Volume ID: VID00017
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: ltuf - AMF8112
oclc - 12029638
alephbibnum - 002452807
 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
    Title Page
        Page 1
    Frontispiece
        Page 2
    Table of Contents
        Page 3
        Page 4
    Letter of transmittal
        Page 5
    Board of control and station staff
        Page 6
    Main
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
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    Index
        Index 1
        Index 2
        Index 3
        Index 4
        Index 5
        Index 6
Full Text


UNIVERSITY OF FLORIDA


AGRICULTURAL EXPERIMENT

STATION





S REPORT FOR THE FISCAL YEAR
ENDING JUNE 30th, 1918


MAY, 1919







































Fig. 1.-Experiment Station Building






CONTENTS
PACE
LETTER OF TRANSMISSAL TO GOVERNOR OF FLORIDA.......................... 5R
BOARD OP CONTROL AND STATION STAFF... ... ..... ........ ......... .. 6R
LETTER OF TRANSMISSAL TO CHAIRMAN BOARD OF CONTROL. .......... 7R
REPORTr OF DIRECTO ..................... ...... .......................... ...-- 7R
Animal Industry, 8R; Plant Nutrition, 9R; Entomological Studies,
10R; Plant Pathological Studies, 10R; Chemistry, 11R; Agronomy,
12R; Changes in Staff, 12R; Publications, 13R; Summary of Bul-
letins, 13R.
REPORT OF AUDITOR................................................ ....... 15R
REPORT OF ANIMAL INDUSTRIALIST ... ............ ..... ............ 16R
Dairy Herd, 16R; Cattle Feeding Experiments, 18R; Hogs, 20R;
Fertilizer Experiments with Cane, Sweet Potatoes and Corn, 23R;
Japanese Cane Fertilizer Experiment, 25R.
REPORT OF PLANT PHYSIOLOGIST...................... ............................ ............ 27R
Field Experiments with Fertilizers, 28R; Experiments to Deter-
mine Potash Requirements of Potatoes, 28R; Experiments to
Determine the Relative Value of Different Sources of Phosphoric
Acid in Complete Fertilizers for Potatoes, 24R; Experiments with
Citrus Trees, 39R; Experiments to Determine the Relative Value
of Different Sources of Phosphoric Acid in Complete Fertilizers
for Citrus Trees, 39R; Influence of Fertilizer Treatment on the
Coloration of Grapefruit, 50R; Influence of Different Ratios of
Phosphoric Acid and Potash in Fertilizers Upon Growth and Fruit
Production in Citrus Trees, 52R; Efficiency of Finely Ground Phos-
phate Rock, Stable Manure and Legumes as a Fertilizer for Citrus
Trees, 52R.
REPORT OF ASSISTANT PLANT PHYSIOLOGIST ................................... 54R
REPORT OF ENTOMOLOGIST...................................... ............... 56R
Velvet-Bean Caterpillar, 56R; Control of Nematodes, 56R; Plant
Bugs, 58R; The Importation of Parasites, 59R; Insects Attacking
Corn, 60R; Insects of the Year, 60R.
REPORT OF PLANT PATHOLOGIST............................................ ........... 62R
Citrus Diseases, 62R; Avocado Diseases, 62R; Avocado Scab, 68R;
Avocado Fruit Spotting, 65R.
REPORT OF ASSOCIATE PIANT PATHOLOGIST.......... ........ ........................ 68R
Diseases of Truck Crops, 68R; Phomopsis of Eggplant, 68R;
Solanaceous Blight, 71R; Damping Off, 75R; Buckeye Rot of
Tomato Fruit, 74R; Truck Disease Survey, 76R; Truck Diseases
of Special Importance, 76R.
REPORT OF CHEMIST. ....................................... 79R
Citrus Experiment Grove, 79R; Chemical Composition of Leaves
and Stems, 81R; Collection of Soil Samples, 83R; Miscellaneous
Work, 83R.
REPORT OF ASSISTANT AGRONOMIST.................................................................84R
Cotton Variety Test, 84R; Sweet Potato Experiments, 85R; Pea-
nuts, 85R.
REPORT OF FORAGE CROP SPECIALIST ............................... ............................ 86R
Field Work on the Experiment Station Farm, 86R; Promising New
Grasses, 86R; Cooperative Plantings, 92R.
REPORT OF FORAGE CROP EXPERIMENT FUND ......................... .........93R
BULLETIN 140.-DIBACK, OR EXANTHEMA OF CITRUS TREES............... 1
Distribution, 4; Dissemination of the Disease, 4; Susceptible Trees,
4; Symptoms of Citrus Dieback, 5; Development, 10; Factors Sug-
gested as Causal Agents, 12; Conditions Complicating the Connec-
tion of Dieback with Soil Organic Matter, 13; Dieback and Ferti-
lizers, 16; Control of Dieback, 19; Summary, 30.
BULLETIN 141.-PORK PRODUCTION IN FLORIDA...................................... 3
Pen Feeding Unprofitable, 35; Choosing a Breed, 36; Grading-up,
36; Care of the Herd, 38; Principles of Feeding, 39; Composition
of Animal Body and Animal Products, 39; Composition of Feeds,
40; How to Calculate Rations, 41; Some Good Rations, 42; Feeding
Experiments, 44; Worms in Swine, 54.





4R Contents
PAGE
BULLrrI 142.- DAIYING IN FLOIm A ........... ... ........ ....... .... 57
More Dairy Cattle Needed, 59; Factors Influencing the Cost of
Milk Production, 60; How Much Should a Good Cow Produce, 61;
Improving the Herd by Selection, 64; Improvement of the Station
Herd, 66; Principles of Feeding, 66; Balanced Rations for Dairy
Cows, 67; Feed and Labor Costs at the Experiment Station, 69;
Home-Grown Feeds Necessary, 71; How Feed Affects Milk, 71;
The Milker as a Factor in Production, 73; Some Dairy Pointers, 75.
BUI.LETIN 143.-FEEDING FOR MILK PRODUCTION ............................ ....... 77
Sorghuni Silage vs. Japanese-Cane Silage, 79; Sorghum Silage
vs. Sweet-Potato Silage, 81; Cottonseed Meal, Peanut Meal, and
Velvet-Bean Meal Compared, 83; Corn Silage vs. Sweet-Potato
Silage, 86.
BULLETIN 144.-FERTILIZERS FOR JAPANESE CANE................................ 89
Applying the Fertilizer, 92; Effect of Cumlete Fertilizers on Yields,
93; Effect of Incomplete Fertilizers, 96.
BULLETIN 145.- M ELANOSE II.................................... .. ... ................ 101
Appearance of Melanose Injury, 104; Nature of Melanose, 106;
Cause, 107; Effects, 110; Conditions Favoring Melanose, 111; Con-
trol, 113.
BuLLu N 146.- ToMATO DisEA 8ss ..........- ..... ........ ............... 117
General Recommendations, 119; Bacterial Blight, 120; Septorial
Blight, 121; Sclerotial Blight, 122; Phytopthora Blight, 123; Fusa-
rial Wilt, 123; Early Blight, 125; Black Spot, 126; Leaf Mould,
126; Buckeye Rot, 127; Brown Rot, 129: Soft Rot, 129; Root-
Knot, 180.
BULLETIN 147.-DISEASES AND INSECT PESTS OF THE PECAN.................. 183
Diseases Injurious to the Pecan, 135; Diseases of Foliage and
Nuts-Scab, 135; Anthracnose, 137; Mildew, 138; Diseases Pri-
marily Affecting the Wood-Pecan Rosette, 139; Dieback, 141; Dis-
eases Affecting the Nuts Only-Pink Mold, 144; Kernel Spot, 144;
Diseases Affecting Foliage Only-Brown Leaf Spot, 145; Nursery
Blight, 146; Leaf Blotch, 146; Minor Troubles, 147; Insects In-
jurious to the Pecan, 150; Pecan Leaf Case-Borer, 150; Pecan Nut
Case-Borer, 152; Pecan Shuckworm, 163; Pecan Cigar Case-
Borer, 154; Fall Webworm, 155; Walnut Caterpillar, 155; Pecan
Bud-Moth, 157; Flat-Headed Apple-Tree Borer, 157; Hickory Twig-
Girdler, 159; Shot-Hole Borer, 160; Oak or Hickory Cossid, 160;
Hickory Phylloxera, 161.
BULLETIN 148.-INSECTS OF A CITRUS GROVE ...................... ........ 165
Injurious Insects, 169; Whiteflies, 170; Common Citrus Whitefly,
172; Cloudy-winged Whitefly, 178; Wooly Whitefly, 181; Other
Whiteflies, 185; Scale Insects, 185; Armored Scales, 187; Unar-
mored Scales, 206; Mealy-bugs, 213; Rust Mite, 220; Red Spiders,
226; Florida Flower Thrips, 226; Large Plant Bugs, 231; Minor
Pests of the Fruit, 236; Scavengers, 240; Citrus Root-Weevil, 240;
Borers of Trunks and Limbs, 241; Minor Pests of Young Trees,
243; Allies of Citrus Grower, 259; Trees that Harbor Citrus In-
sects, 262; Publications Concerning Citrus Insects in Florida, 263.
PaEss BULLETINS
278.-Comparisons of Corn Silage 284.-Sweet-Potato Root-Weevils.
and Sweet-Potato Silage for 285.-The San Jose Scale.
Milk Production. 286.-The Boll Weevil in Sea Island
279.-Citrus Foot Rot. Cotton.
280.-Sweet-Potato Caterpillars. 287.-Controlling Poultry Lice.
281.-Hog Raising in Florida. 288.-Bulletins and Reports on
282.-Bulletins and Reports on Hand.
Hand. 289.-Avocado Scab.
283.-Pumpkin Bugs in Citrus 290.-Onion Thrips.
Groves. 291.-Peanut Meal for Hog Feeding.























Hon. Sidney J. Catts,
Governor of Florida,
Tallahassee, Fla.
Sm: I have the honor to transmit herewith the annual report
of the Director of the Florida Agricultural Experiment Station
for the fiscal year ending June 30, 1918.
Respectfully,
JOE L. EARMAN,
Chairman of the Board of Control










BOARD OF CONTROL
JOE L. EABMAN, Chairman, Jacksonville, Fla.
E. L. WARTMANN, Citra, Fla.
T. B. KING, Arcadia, Fla.
J. B. HODGES, Lake City, Fla.
J. T. DIAMOND, Milton, Fla.
BRYAN MACK, Secretary, Tallahassee, Fla.
J. G. KELLUM, Auditor, Tallahassee, Fla.

STATION STAFF
P. H. ROLFS, M.S., Director.
J. M. SCOTT, B.S., Animal Industrialist and Vice Director.
B. F. FLOYD, A.M., Plant Physiologist.
M. NOTHNAGEL, Ph.D., Assistant Plant Physiologist.
J, R. WATSON, A.M., Entomologist.
I. E. STEVENS, M.S., Plant Pathologist.
0. D. SHERBAKOFF, Ph.D., Associate Plant Pathologist.
S. E. COLLISON, M.S., Chemist.
A. M. SMrrH, B.S., Assistant Chemist.
J. E. TURINGTON, Ph.D., Assistant Agronomist.
J. B. THOMPSON, B.S., Forage Crop Specialist.
O. W. WEAVER, B.S., Editor.
T. VANHYNING, Librarian.
K. H..GRAHAM, Auditor and Bookkeeper.
E. G. SHAW, Secretary.
G. UMLAUF, Gardener.
G. C. OBERHOLTZER, Farm Foreman.









Report for the Fiscal Year
Ending June 30, 1918



Hon. Joe L. Earman,
Chairman, Board of Control.
SIR: I have the honor to submit herewith my report on the
work and condition of the Agricultural Experiment Station for
the fiscal year ending June 30, 1918; and I request that you
transmit the same, in accordance with the law, to the Governor
of the State of Florida.
Respectfully,
P. H. ROLFS,
Director.

INTRODUCTION
The work of the Florida Experiment Station during the fiscal
year ending June 30, 1918, has given encouraging and satis-
factory results. Owing to the serious national crisis due to the
European war it has been almost impossible to maintain the
institution at the high efficiency it had attained. This difficulty
was due to the large number of workers who were drafted into
the war work, or who took the places of those who were drafted
and severed their connection with the institution. Fortunately
our institution lost none of the leaders of the projects, and while
the work has been greatly impeded for lack of trained assistance,
a very large amount of most useful work has been accomplished
for the State.
The amount of war work done by different members of the Ex-
periment Station staff is not easily enumerated nor can it be over-
estimated. Up to June 5, 1918, the Director was Chairman of
the State Council of Defense. Much of his time was consumed
in this capacity, either directing the organization of advanced
work in the State or in stimulating greater crop production.
The greater crop production of Florida has made a profound
impression upon the people of our own state as well as those
outside its borders.





Florida Agricultural Experiment Station


Every member of the staff, as well as the clerical force, con-
tributed materially toward the winning of the war. This was
done in so many different lines that to enumerate them would
exceed the limits of this brief report. It is needless to say that
everyone took a leading part in almost every special war activity
that was inaugurated by the Council of National Defense. Great
stress was laid on giving assistance in any emergency that might
arise. The decreased farm labor available in the State made the
situation unusual, and required the highest degree of skill to
make our recommendations and work effective on the farms of
Florida.
ANIMAL INDUSTRY
The work of this Department has been continued along the
lines indicated in previous reports. Special attention has been
given to the effects of feeding different Florida grown products
for pork and for milk production. The high prices of feed and
the difficulty of transportation have necessitated more extended
use of home grown feeds. In the dairy work we have compared
velvet bean feed (beans and pods ground together), peanut meal
feed and cottonseed meal for milk production. Feeding experi-
ments have been and are still being carried on to determine how
much peanut meal feed can be fed to hogs and still produce pork
of good quality.
Velvet bean feed and peanut meal feed were each found to be as
economical a milk producer as cottonseed meal, at the following
prices per ton:
Cottonseed meal................................................50.00
Peanut m eal feed.............................................. 40.00
Velvet bean feed............................................ 82.00
It was found that as much as 15% of the ration for hogs could
be peanut meal feed and still produce good hard pork. Experi-
ments in feeding velvet beans to hogs for pork production and
also to the breeding herd, are under observation. So far velvet
beans have not been found entirely satisfactory as a feed for
hogs.
Farmers and livestock men in general have taken a more
active interest in the work that the Station has been doing along
this line. This has been very noticeable in the character and
number of inquiries that have come to the office for information
on the best crops to grow and how to grow them; the best feeds
to use and how to combine them for most satisfactory results.






Annual Report, 1918


These inquiries have come from the swine growers, dairymen,
general farmers and livestock men of the State.

PLANT NUTRITION
The work in plant physiology was somewhat broadened. The
results of the studies of the food requirements of citrus trees
with special reference to phosphoric acid and potash, have shown
that bearing trees receiving complete fertilizer treatment pre-
vious to 1914, were able to maintain normal growth and yields
with fertilizers containing only small amounts of potash. Formu-
las carrying 2% potash produced the same quality and amount
of fruit as those containing 6% and 12% potash, respectively.
Young citrus trees, planted in 1917 on virgin soil, and fed with
fertilizers containing various amounts of potash have made the
following relative increases in their trunk diameters:
No potash.................... ....... ..... ...... 100%
1% ... .. ... .. ................. .. ............... ... 105%
2% .... ....... .............. ... ......... .. 104%
3% .............................. ........................ 114%
4% ............................................... 136%
There was no difference in the gross appearance of the trees
receiving the various amounts of potash.
The fact that no injurious effects have been evident in the
bearing trees on account of the reduced amounts of potash used,
and the knowledge that this laboratory was carrying on these
experiments and making systematic grove studies, has tended
to allay the potash panic that threatened among the citrus
growers at the beginning of the European War.
The year's work with potatoes planted in virgin soil and fer-
tilized with formulas containing none to 5% potash, showed that
the plants could make a normal growth with the potash that
was contained in such soils, but the yield of tubers would be
small. The relative yields where the various amounts of potash
were used, were as follows:
No potash...................... .. ............. ... 100%
1% ....... ......-. ...... ............. 152%
3% .......................... ......... .. 185%
5% ............ ......... ... .......... ... 190%
Experiments have been conducted with both citrus trees and
potatoes to determine the relative efficiency of the raw phos-
phates and acid phosphate, where each were used in connection





10R Florida Agricultural Experiment Station

with full rations of nitrogen and potash. Where used as a ferti-
lizer for'young citrus trees planted on virgin soil, the relative
increases of the trunk diameters were as follows:
Acid phosphate .................................................. 100%
Steamed bone.................................... 98%
Soft phosphate...... ..... ...................................... 89%
Fine ground pebble phosphate....................... 83%
Where used as a fertilizer for potatoes planted in virgin sandy
soil, the yields relative to that produced where no phosphoric
acid was used, were:
No phosphoric acid.................................... ...... 100%
Acid phosphate .................. .............. 236%
Soft phosphate........... ........ ................ 150%
Fine ground pebble phosphate........................ 188%
Where used as a fertilizer for young citrus trees that had been
fed with complete fertilizers the four years previous to the time
the experiment was started, the increase in trunk diameters rela-
tive to that produced by acid phosphate was:
Acid phosphate ............................................... 100%
Steamed bone.................................................... 103%
Soft phosphate.......................................... 102%
Fine ground pebble phosphate........................ 99%
ENTOMOLOGICAL STUDIES
This work has taken three main directions: (1) Best methods
for the control of root-knot; (2) further observations and
studies on the velvet bean caterpillar; and (3) control of plant
bugs in truck gardens and citrus groves.
Owing to the impossibility of securing supplies of cyanamid,
the experiments in cyanamid for the control of root-knot have
been temporarily suspended.
The recommendation of the Entomologist that summer fallow-
ing be employed as a measure against root-knot, has been fol-
lowed out in a number of instances.
An important work carried out by this department was the
importation from California of a whitefly-eating lady beetle
(Delphastus catalinae).
Two bulletins, one on citrus insects and the other on garden
insects, were prepared by the Entomologist.

PLANT PATHOLOGICAL STUDIES
The study of citrus diseases has been continued, special stress
being laid on the control of melanose and. gummosis The caus-






Annual Report, 1918


ative agent of the former disease is well known and a considerable
amount of experimental work has been carried out to determine
the most effective manner of controlling it. The causative agent
of the latter is not known, and the large amount of work that
has been done on it shows quite conclusively that the disease is
of a rather elusive and insidious character.
At the earnest solicitation of the avocado growers of South
Florida, the study of avocado diseases was taken up. It was
found that one of the diseases of this fruit is produced by the
same species of fungus that produces the scab of citrus fruits.
It is quite probable that this fungus is becoming adapted to the
avocado. Definite recommendations have been made for its
control. The fruit spotting of avocado has caused a considerable
amount of damage. The active agent causing this is not known,
but definite steps are being taken to carry out further investiga-
tions on this point.
Much good work has been done and progress made with dis-
eases of truck crops. Investigations show that some of the very
serious diseases of truck crops are introduced with the seed.
A considerable amount of exact work has been done with the
view of freeing the seed from disease-producing fungi and bac-
teria. This is naturally a very difficult and highly technical piece
of work, since the poisons that would destroy the spores of the
organisms adhering to or within the seed, would be very likely to
also destroy the germ of the seed. The work has progressed far
enough to indicate quite clearly that in some cases it is possible
to free the seed from diseases by methods of disinfection. In
many other cases to obtain disease free seed it would be necessary
to observe methods of seed selection and sanitary production of
the same.
CHEMISTRY

The demand for chemists during the war has been so great
that the work of this department has been more seriously inter-
fered with than any other. In spite of adverse conditions, the
project as outlined in former annual reports has been continued.
Unfortunately, it has been impossible to make the large amount
of chemical analyses that are desired in connection with this
work. The work done in the experimental grove at Tavares has,
however, given some satisfactory and definite results.


11R





Florida Agricultural Experiment Station


AGRONOMY
The agronomy project has been continued practically the same
as heretofore, with the exception that the line of work started
on sweet potatoes has been discontinued. The Assistant Agrono-
mist has made tests of various varieties of cotton, noting results
of boll weevil attacks on same. Experiments showing the effect
of different chemical fertilizers on crops planted on virgin soils
on the State Farm at Raiford have been continued. These have
shown most interesting results and when completed will give us
very valuable data.

CHANGES IN STAFF
The changes in the personnel of the staff during this fiscal
year, while rather numerous, have not involved the heads of
important projects.
July 16, 1917, A. M. Smith, B.S. (Pa. State Agr. Col.) began
work as Assistant Chemist.
August 1, 1917, Mildred Nothnagel, Ph.D. (Indiana Univ.)
took up the duties of Assistant Plant Physiologist.
October 1, 1917, J. B. Thompson, B.S. (Kansas Agr. Col.)
took up the work of Forage Crop Specialist.
October 1, 1917, F. F. Halma, Assistant Horticulturist, re-
signed his position to take up post-graduate work with the
University of California.
October 1, 1917, J. A. Miller, B.S. (Fla. State Agr. Col.) took
up the work of Assistant Horticulturist, resigning on December
1, 1917.
November 11, 1917, L. T. Nieland, foreman of the Experiment
Station Farm, answered the "call to the colors", entering the
Navy.
November 11, 1917, G. C. Oberholtzer took up the duties of
Foreman of the Experiment Station Farm.
December 10, 1917, C. W. Long, Assistant to the Animal
Industrialist, resigned his position to enter the Naval Reserves.
December 31, 1917, C. L. Sensabaugh began work as Gardener
to the Experiment Station, resigning on February 24, 1918.
January 3, 1918, H. L. Dozier, M.S. (Fla. State Agr. Col.) took
up the work of Laboratory Assistant in Entomology, resigning
on April 15, to enter the Health Department of the U. S. Service.


12R






Annual Report, 1918


13R


March 7, 1918, G. Umlauf began work as Gardener to the
Experiment Station.
May 15, 1918, J. Matz, Assistant in Plant Pathology, resigned
his position.
PUBLICATIONS.

Following is a list of the publications issued by the Experi-
ment Station for the fiscal year ending June 30, 1918.


Bulletin
Numbw Title Edition
140 Dieback, or Exanthema of Citrus Trees............. 15,000
141 Pork Production in Florida..................... .... 15,000
142 Dairying in Florida....................... ..................... 20,000
143 Feeding for Milk Production........ ...................... 20,000
144 Fertilizers for Japanese Cane............................... 15,000
145 M elanose II..................................... ..... .......... 15,000
146 Tomato Diseases... .......... ................. 15,000
147 Diseases and Insect Pests of the Pecan............ 15,000
148 Insects of the Citrus Grove................................. 15,000
Totals ....._ ............. ......................................145,000
ANNUAL REPORT, 1916-17, with index to all publica-
tions for the year... ........................................ 4,000


Total
Pages Pages
32 480,000
24 360,000
20 400,000
12 240,000
12 180,000
S16 240,000
16 240,000
32 480,000
104 1,560,000
268 4,180,000
114 456,000


SUMMARY OF BULLETINS
140. Dieback, or Exanthema of Citrus Trees. (B. F. Floyd.) Pp. 82,
figs. 15. This bulletin discusses in detail the nature of the disease, the
causal factors, and the methods of control.
141. Pork Production in Florida. (John M. Scott.) Pp. 24, figs. 1.
Gives some information as to methods of feeding, choosing a breed and
grading up, and general care of the herd. It also gives a short discussion
of the composition of the animal body and the composition of feeds. The
remainder of the bulletin deals with the results of a number of feeding
experiments for pork production.
142. Dairying in Florida. (John M. Scott.) Pp. 20, figs. 5. Factors
influencing the cost of milk production, improving the herd by selection,
principles of feeding, and feed and labor costs are discussed. The ad-
vantages of the silo, how feeds affect milk, the milker as a factor in
production, and the qualifications of a good dairyman are taken up.
143. Feeding for Milk Production. (John M. Scott.) Pp. 12, figs. 1.
Results are given of feeding experiments which show the value of different
feeds for milk production.
144. Fertilizers for Japanese Cane. (John M. Scott.) Pp. 12, figs. 1.
A discussion on the effects of complete and incomplete fertilizers. Also
the effect of the various sources of ammonia, various sources of phosphorus,
and of ground limestone on the yield of green material.
145. Melanose II. (H. E. Stevens.) Pp. 16, figs. 7. This bulletin
gives in detail the nature and cause of melanose, and discusses the best
method of control.
146. Tomato Diseases. (C. D. Sherbakoff.) Pp. 16, figs. 13. This
bulletin discusses the most common fungus and bacterial diseases of the
tomato, and recommends the best methods for their control.
147. Diseases and Insect Pests of the Pecan. (J. Matz.) Pp. 82,
figs. 29. A discussion of the diseases and insect pests of the pecan, and the
best methods of control.





14R Florida Agricultural Ezperiment Station

148. Insects of a Citru Grove. (J. R. Watson.) Pp. 104, gs. 68.
This bulletin describes insects and other animals in Florida citrus groves;
gives an account of their life history and states the best methods for their
control. Formulas for the common insecticides are included.

PRESS BULLETINS
No. Title Author
278 Comparisons of Corn Silage and Sweet-Potato Silage for
Milk Production ............................................................ .. Scott
279 Citrus Foot Rot.................. ......... .... ........ E. Stevens
280 Sweet-Potato Caterpillars............................................J. R. Watson
281 Hog Raising in Florida................................. ...................... A. P. Spencer
282 List of Reports and Bulletins on hand..................................Oct. 24, 1917
283 Pumpkin Bugs in Citrus Groves................................ R. Watson
284 Sweet-Potato Root-Weevils.............................................. R. Watson
285 The San Jose Scale........................... ............ R. Watson
286 The Boll Weevil in Sea Island Cotton........ ................. J. .Watson
287 Controlling Poultry Lice.. ...................... ..... ................ -J. R. Watson
288 List of Reports and Bulletins on hand....................M........March 18, 1918
289 Avocado Scab.......... .... .............. ...............H. E. Stevens
290 Onion Thrips...... .............................................................. J W atson
291 Peanut Meal for Hog Feeding............................................. M. Scott







Annual Report, 1918


REPORT OF AUDITOR

P. H. Rolfs, Director.
SI: I respectfully submit the following report of the credits
received and expenditures vouchered out of the funds as speci-
fied:
RECEIPTS
Balance Receipts Total
Adams Fund ..................................... ...... ..... ... ... .. $15,000.00 $15,000.00
Hatch Fund ................................. .................. ... 15,000.00 15,000.00
State Experiment Fund ................ ....... $ 8.35 4,491.65 4,500.00
State Repair and Building Fund- .......... 119.75 750.00 869.75
State Printing Fund............................. 2,588.59 4,000.00 6,588.59
Sales, farm ........................... ............ 245.00 5,582.78 5,827.78
Forage Investigation ........- --- .. ... .............. 2,500.00 2,500.00
Miscellaneous .......................................... 351.74 5.88 357.57
$ 3,313.43 $47,330.26 $50,643.69


EXPENDITURES
Hatch Adams
Salaries ............................. ........ .......... $ 7,689.13 $11,443.96
Labor ......................... ............ ......... ..... 3,506.37 950.87
Publications ............................................ 1,187.40 ... .............
Postage and stationery............................ 668.82 53.78
Freight and express ...._......- ............ 156.66 115.01
Heat, light, water and power-.........-..... 163.90 233.57
Chemicals and laboratory supplies .......... 6.93 323.61
Seeds, plants and sundry supplies .......... 175.26 275.72
Fertilizers ....... .............. ...... .... ......... 89.17 124.75
Feeding stuffs ..... .................. .- .......... 609.26 .... .........
Library .............................. ..... . 358.49 36.08
Tools, machinery and appliances....-......... 168.96 74.88
Furniture and fixtures ..........-.......... ... 165.90 20.75
Scientific apparatus and specimens ..... ............. 376.10
Livestock ............... ..................... ........................
Traveling expenses .............................................. 915.62
Contingent expenses .................................. 20.00 ... ...........
Buildings and land ......................... .. 33.75 55.30
Balance ................ ... .................... ........ ..................


Other
Sources
$ 1,260.00
3,551.22
4,029.67
43.34
262.02
70.78
453.09
298.00
3,582.47
6.08
98.23
120.05
1,241.00
624.94
20.00
554.9
4,427.87


Totals .................................................. $15,000.00 $15,000.00 $20,643.69

Respectfully submitted,
K. H. GRAHAM,
Auditor.


15R




Florida Agricultural Experiment Station


REPORT OF ANIMAL INDUSTRIALIST
P. H. Rolfe, Director.
SIR: I submit the following report of the Department of
Animal Industry for the fiscal year ending June 30, 1918.
DAIRY HERD
Four purebred Jersey cows were purchased during the year:
Florida Lavender No. 260294 out of Florida Rosa No. 222006 by
Florida Duke No. 68915; Madeline's Fancy Lass No. 301811, out
of Beau Brummel's Madeline No. 181221 by Clover Duke's Golden
No. 86597; Fairy Boy's Pennithorpe No. 344760, out of Penni-
thorpe's Fairy No. 271069 by Hauteville Fairy Boy No. 90952;
and Gamboge's Christabel No. 390681 out of Oxford Christabel
No. 288722 by Gamboge's Knight's Prince No. 109544.
Mr. Thomas Danson of Jacksonville, Fla., purchased from the
Station herd a purebred Jersey bull calf and two purebred Jersey
heifer calves. Mrs. B. E. Takach of Sanford, Fla., purchased a
purebred Jersey bull calf.
Except for the increase in calves, there have been no other
changes in the herd since the last report. All of the purebred
heifer calves have been retained except the two sold to Mr. Dan-
son. The heifer calves from the best producing grade cows have
been retained. The bull calves from the grade cows and the
heifer calves from the poorest producing grade cows were dis-
posed of when dropped.
Table No. 1 gives the herd record for the year July 1, 1917
to June 30, 1918. This shows a great variation in the amount of
milk produced by the different cows in the herd. Cow No. 61
produced the most milk during the year, 5649.3 pounds or 656.8
gallons. This is a fairly good record. One reason for this good
record is the fact that she produced milk for 332 days during the
year. There are, however, six other cows in the herd which pro-
duced over 500 gallons of milk each during the year. It will
be seen from the table that these six cows produced milk for 300
days or more during the year.
Cows Nos. 33, 51, and 104 were the poorest producers in the
herd. These cows produced an average of only 163 gallons of
milk during a period of 203 days.
The entire dairy herd is composed of 33 purebred and 86 grade
Jerseys. The purebreds are divided as follows: Three bulls,
sixteen females two years old and over, four females under two
and over one year old, and ten females under one year old.


16R





Annual Report, 1918 17R

TABLE 1.-HEBD RECORD, JULY 1, 1917 TO JUNE 30, 1918



z ca
3 ^ s a S c a I

8 Ug M Ae 1 1s > as0 0 N iQ
1...... 5069.5 329 5.2 263.6 $123.00 589.47 $188.63 $ 89.41 $ 99.22
7...... 4433.2 316 5.0 221.6 103.40 515.48 164.95 80.74 84.21
9...... 4239.5 318 4.6 254.3 118.68 492.96 157.75 77.77 80.98
18...... 5448.7 3281 5.2 283.3 132.20 633.57 202.74 104.77 97.97
20...... 4142.8 293 4.2 173.9 81.12 481.72 154.15 76.33 77.82
31...... 2974.9 277 5.1 151.7 70.76 345.91 110.69 61.91 48.78
33....- 1291.7 1771 4.7 50.7 23.64 150.19 48.06 35.51 12.55
35...... 3112.9 253 5. 158.7 74.04 361.96 115.83 60.52 55.33
36...... 4592.2 306 4.8 220.4 102.84 533.97 170.87 59.77 111.10
41 ...... 4885.8 300 4.7 229.6 107.12; 568.11 181.79 65.96 115.88
42..... 3990.5 268 4.2 167.6 78.20 464.01 148.48 48.43 100.05
47...... 3449.4 304 5.1 175.9 82.08 401.09 128.351 69.90 58.45
49...... 2494.8 284i .5 137.2 64.00 290.09 92.83 50.90 41.93
50...... 2306.9 180 5. 124.5 58.08 268.24 85.8440.38 45.46
51...... 1467.6 228 5.2 76.3 35.60 170.65 54.6145 9.28
52...... 2604.5 218 4.9 127.6 59.52 302.84 96.91 47.67 49.24
53 ...... 1746.9 166 4.5 78.6 36.68 203.12 65.00 32.8 32.20
54...... 2469.2 295 5. 123.4 57.56 287.11 91.87 53.93 37.94
55...... 2161.5 231 5.2 112.4 52.44 251.334 80.42 41.24 39.18
56...... 2346.6 232 4.9 114.9 53.60 272.86 87.31 44.19 43.12
57...... 1943.1 219 5.2 101.0 47.12 225.94 72.30 41.67 30.63
59...... 4880.7 303 4.7 229.3 107.00 567.52 181.61 89.41 91.20
61...... 5649.3 332 4.0 225.9 105.40 656.89 210.20 90.08 120.12
62...... 3482.5 279 4.7 163.6 76.32 404.94 129.58 63.18 66.40
69...... 3854.6 286 4.4 169.6 79.1 448.20 143.42 55.61 87.81
81.... 2452.2 222 4.5 110.3 51.44 285.14 91.24 39.45 51.79
104.... 1457.0 206 4.4 64.1 29.88 169.41 54.21 30.37 23.84
109...... 4036.9 290 4.7 189.7 88.52 469.40 150.21 71.26 78.95
115...... 4039.1 308 4. 169.6 79.12 469.66 150.291 71.30 7899
117.... 2643.6 1702 3.7 97.8 45.641 307.39 98.36 35.97 62.39

REGISTER OF MERIT RECORD
During the year Creole's Lassie Sue No. 306835 completed her
year's register of merit record. The required test began Sep-
tember 19, 1916 and closed September 18, 1917. In the 365 days
she produced 7708.6 pounds or 896.3 gallons of milk, and 374.32
pounds of butter fat or 436.7 pounds of butter. During this test
she carried a calf 209 days. Her register of merit number is
7126, Class AA.
Creole's Lassie Sue No. 306835 was bred and raised in Florida
and up to date is the only Florida bred and raised Jersey cow
that has made the register of merit.





Florida Agricultural Experiment Station


TABLE 2.-AGE AND BRDm oF Cows


z V
i I 4.
0 & '.1


7
6%
5
5
5
5
6
9
4
4
4
4
4
4
4
4
3%
3%
6
6
5
5
3
3%
3%
8
7


Grade Jersey
Grade Jersey
Grade Jersey
Jersey
Jersey
Jersey
Jersey
Grade Jersey
Grade Jersey
Grade Jersey
Grade Jersey
Jersey
Grade Jersey
Grade Jersey
Grade Jersey
Grade Jersey
Jersey
Grade Jersey
Grade Jersey
Jersey
Grade Jersey
Jersey
Grade Jersey
Grade Jersey
Grade Jersey
Jersey
Jersey
Grade Jersey
Jersey
Jersey


CATTLE FEEDING EXPERIMENTS

Cattle feeding experiments were conducted jointly by the
Bureau of Animal Industry, U. S. Dept. of Agr., the Florida Ag-
ricultural Experiment Station and farmers having the cattle
and feed.
The first of these experiments was conducted on the farm of
L. K. Edwards, Irvine, Fla., 220 head of cattle being used.
These were native Florida steers and were from three to five
years old. This experiment lasted 84 days.
On November 5 the steers were taken from a woods pasture,
dipped, weighed and turned into an 80 acre field of Florida velvet
beans. This field supplied feed for just 28 days, and on December
3 the steers were weighed, showing a gain of 1820 pounds.


May 20, 1918
May 8, 1918
Oct 28, 1917
May 3, 1918
May 21, 1918
April 2, 1918
April 22, 1918
Nov. 25, 1917
Jan. 2, 1918
Dec. 20, 1917
March 10, 1918
April 27, 1918
March 20, 1917
May 2, 1918
Oct. 28, 1917
April 12, 1918
May 1, 1918
April 15, 1918
April 17, 1918
May 20, 1918
April 4, 1918
Nov. 11, 1917
April 17, 1918
Oct. 31, 1917
Jan. 18, 1918
Nov. 15, 1917
Dec. 3, 1917
April 25, 1918
Nov. 2, 1917
Jan. 6. 1918





Annual Report, 1918


Beginning December 3 the feed consisted of sorghum silage,
velvet beans in the pod, and cottonseed meal.
The amount and value of feed consumed from November 5 to
January 28, the end of the experiment, was as follows.

80 acres velvet beans, estimated............................ ............................ $400.00
190 tons sorghum silage @ $ 5................ ..... .. ................ 950.00
17.7 tons velvet beans in pod @ 30............................. ...... 531.00
17 tons cottonseed meal @ 52....................... ....................... 884.00
Total ..................................... ........................... ...... $2765.00

At the beginning of the test the steers cost $7,681.20 at the
farm. This made a total cost of $10,446.20 for feed and steers.
When sold on January 28 the steers weighed 141,630 pounds.
At eight cents a pound they had a value of $11,330.40 and repre-
sented a profit of $4.02 per head. No credit is given for the
manure produced and no charge made for labor of feeding the
steers.
Table No. 3 shows the weights at the beginning of the experi-
ment and at intervals of every 28 days. It also shows the
average daily gains.
Table No. 4 shows the financial statement.
These results do not show very satisfactory financial returns.
This is due largely to the small gains made by the steers. The
small gain in weight was due very largely to the fact that about
40 head of the steers failed to learn to eat the feed. Range cattle
often require a long time to learn to eat grain.

TABLE 3.--CATTLE FEEDING EXPERIMENT NO. I
Weights and Gains in Pounds

Dates Weights Taken............... Nov. 5 Dec. 3 Dec. 31 Jan. 28
Number of Cattle........... ............ 220 220 220 220
Total weight ............................. 128,020 129,840 129,650 141,680
Average weight per head............... 582 590 589 644
Average gain per head.......................................... 8 55
Average daily gain per head................ 29 .............. 1.97
Total average daily gain............................ .....--- .... ........ .74

TABLE 4.-FINANCIAL STATEMENT
To 220 steers, weight 128,020 lbs. @ 6c per lb- ......... ..........$ 7,681.20
Value of feed consumed................................ ...... ... ......... 2,765.00
Total .. .-.. .....................................................................$10,446.20
By 220 steers, weight 141,630 tbs. @ 8c per Ib ..............................$11,880.40
Total profit................................................. ........ .............. .....884.20
Profit per head .......................... .......................... ............................. 4.02


19R





Florida Agricultural Experiment Station


A second cattle feeding experiment was conducted at Komoko
Farm near Newberry. In this experiment 116 head of native
Florida steers were used. These steers were from three to five
years old and were of about the same quality as those used in the
feeding experiment on Mr. Edwards' farm.
This feeding experiment was begun November 6, 1917, and
continued until January 17, 1918, a period of 72 days. The cattle
had been running on woods pasture, and had been dehorned
some time in September.
On November 6, when the steers were turned into a field of
velvet beans, the total weight was 67,270 pounds, or an average
of 580 pounds per head. The 85 acre velvet bean field used as
pasture was valued at $765. The steers cost $3363.50, making
the total cost of feed and steers $4128.50. When sold, the cattle
weighed 69,500 pounds. At seven cents per pound the cattle
had a value of $4865, or a profit of $6.35 per head. No credit is
given for manure produced, and no charge made for the labor
of feeding.
Table No. 5 shows the weights at the beginning of the experi-
ment and at intervals, and the gains produced.
Table No. 6 shows the financial statement.
TABLE 5.-CATTLE FEEDING EXPIMErNT II
Weights and Gains in Pounds

Dates Weights Taken....................... Nov. 6 Dec. 4 Dec. 19 Jan. 17
Number of cattle........................ 116 116 116 116
Total weight ..................... ..... 67,270 67,60 65,220 69,500
Average weight per head..-- 580 583 562 599
Average gain per head...................... ....... 3.0 -21.0 37.0
Average daily gain per head.... ......... .107 -1.4 1.32
Total average daily gain per head .................... ........... 267

TABLE 6.-FINANCIAL STATEMENT
To 116 steers, weight 67,270 lbs. @ 5c per b .......................................$ 3368.50
Value of feed consum ed................................................................................ 765.00
Tulal ................... ...................................................... ............ $ 4128.50
By 116 steers, weight 69,500 lbs. @ 7c per lb......................... ...........$ 4865.00
Total profit.............................................. .............................................. 736.50
Profit per steer................... .......................................... .................. 6.3

HOGS
The Jacksonville Chamber of Commerce donated a fine pure-
bred-Berkshire boar. No other animals were added to the herd
except the increase in pigs from the sows.


20R







Annual Report, 1918 21R

FEEDING EXPERIMENTS
COMPARISON OF PEANUT MEAL AND VELVET BEAN FEED
A feeding experiment began on December 4, 1917, 15 hogs
being used. They were divided into three lots of five hogs each.
The hogs in lot I were fed shelled corn; those in lot II were fed
shelled corn 6/2 parts and peanut meal feed 1 part, by weight, or
15.3 percent of the ration was peanut meal feed (by peanut
meal feed is meant peanuts and pods ground together, with oil
extracted) ; and hogs in lot III were fed shelled corn 5 parts and
velvet bean feed (pods and beans ground together) 1 part by
weight. In addition to the grain, each lot of hogs received 10
pounds of green rape daily.
Table No. 7 shows the weights and gains, table No. 8 the
pounds of feed consumed, and table No. 9 shows the daily ration
per lot.
TABLE 7.-WEIGHTS AND GAINS IN POUNDS
SLOT I LT IILoT III
Weights at beginning of test Dec. 4, 1917.................... 466.6 475.0 456.6
Weights at close of test Feb. 3, 1918............................ 716.6 663.3 636.6
Gain in 62 days............................ ....................... 250.0 188.3 180.0
Average gain per head............................. .......... 50.0 37.66 36.0
Average daily gain per head.............................. 0.80 0.61 0.58
Average daily gain per 1000 lbs. live weight ......... 8.57 6.42 6.35
Pounds of feed to make one lb. of gain...................... 3.86 5.16 5.2

TABLE 8.-POUNDS OF FEED CONSUMED
LOT 1 i Lo II LoT III
Corn ..................................... ........ ...... ............ 967.0 f-- 44 0 750.0
Peanut m eal feed............................................................................ 130.0 .........
Velvet bean feed .................................... ..... .................... .. ....... 185.0


TABLE 9.-DALY RATION PER LOT
CORN PEANUT VELVET BEAN
MEAL FEED FEED
Pounds Pounds Pounds
Lot I...........................-.......---...--- ....... .. 15.6 ................... ................... ...
.I........................6..................
Lot II .....................6 2..................... 13.6 2.1 ..........
Lot III .....12.1................2...9
Lot In ............................. ............... 12.1 ........................ 2.9

At the close of the experiment the hogs were shipped to Jack-
sonville and sold to Armour & Company. The hogs were
slaughtered and the carcasses placed in the cooler where they
remained for about 48 hours. Upon examination it was found
that all carcasses had chilled hard, and those produced by feed-





Florida Agricultural Experiment Station


ing peanut meal feed could not be distinguished from those fed
on corn only.
This test indicates that as much as 15 percent of the ration
for fattening hogs for market can be peanut meal feed and still
produce hard pork.
COOKED VELVET BEAN FEED
On February 20 an experiment was started which continued
for 85 days, closing May 15. In this test three hogs were used.
They were fed shelled corn and cooked velvet bean feed. The
velvet bean feed was weighed each time before being cooked. The
velvet bean feed was cooked from thirty to forty minutes.
At the beginning of the test the shelled corn and velvet bean
feed were fed in proportions of one part velvet bean feed to three
parts corn by weight. The proportion of velvet bean feed was
increased from time to time so that during the last thirty-five
days of the test the hogs were getting one part corn and two
parts velvet bean feed by weight.
At the beginning of the test the three hogs weighed 316 pounds.
At the close of the test they weighed 440 pounds or a gain of 124
pounds in 85 days. This is an average daily gain of .49 of a
pound or an average daily gain per 1000 pounds live weight of
4.62.
At the close of this feeding experiment the hogs were shipped
to Jacksonville and sold to Armour & Company. The animals
were slaughtered and the carcasses were placed in the cooler
where they remained for some time. On examination it was
found that the carcasses chilled hard.
The most interesting part of this experiment is the fact that
velvet bean feed produces a hard pork.
PEANUT MEAL FEED FOR PORK PRODUCTION
On March 7, 1918 an experiment was started which continued
for 97 days, closing June 12, with four lots of hogs, two hogs in
each lot. The object of this experiment was to determine if
possible how much of the ration for fattening hogs could be made
up of peanut meal feed, and still produce hard pork.
The hogs in lot I were fed corn five parts and peanut meal feed
one part by weight. Lot II was fed corn four parts and peanut
meal feed one part by weight. Lot III was fed corn three parts
and peanut meal feed one part by weight. Lot IV was fed corn
only.


22R






Annual Report, 1918


Table No. 10 shows the weights and gains. Those in lot II
were the only hogs that made a satisfactory gain. Table No. 11
shows the daily ration fed each lot of hogs.
At the close of the experiment the hogs were shipped to Jack-
sonville and sold to Armour & Company.

TABLE 10.-PIG FEEDING EXPERIMENT
Weights and Gains
I LOT I LOT II LOT II Lor IV
Pounds Pounds Pounds Pounds
Weight at beginning of test March 7, 1918.. 190 223.3 203.3 206.6
Weight at end of test June 12, 1918............. 275 300.0 340.0 245.0
Gain in 97 days.................................. ......... 85 76.7 136.7 38.4
Average daily gain per head.................... .44 .39 .7 .2

TABLE 11.-DAILY RATIONS FED PER LOT
FEEDS i LOT I LOT I III O LOT IV
P sounds Pounds pounds Pounds
Corn ........ -- -................. ............ 5.5 6.25 5.3 7.25
Peanut meal feed ............ ........................... 1.1 1.56 1.77

The animals were slaughtered and the carcasses were placed
in the cooler where they remained for some time. Upon exami-
nation it was found that the carcasses of the hogs fed five parts
corn and one part peanut meal feed produced pork of good
quality, but did not chill hard when put in the cooler. The lard
was of a good, white color and no appearance of oil, but it was
soft. The carcasses of the hogs fed four parts corn and one part
peanut meal feed, were of about the same character as those of
the hogs fed five parts corn and one part peanut meal feed.
The carcasses of the hogs fed three parts corn and one part
peanut meal feed produced pork of good quality, but when placed
in the cooler did not chill hard. The meat was soft but not oily.
The only noticeable difference in the character of the pork
produced from hogs fed peanut meal feed and those fed corn only
was that the former did not chill hard in the cooler.

FERTILIZER EXPERIMENTS WITH CANE, SWEET POTATOES
AND CORN

The following results have been obtained from replanting
Japanese cane. In the spring of 1909 a fertilizer test on Jap-
anese cane was begun. This experiment was continued until the
crop of 1914 was harvested. The field was then plowed up and


23R





24R


Florida Agricultural Experiment Station


in the spring of 1915 a part of it known as Section A was re-
planted to Japanese cane, Section B was planted to sweet pota-
toes, and Section C to corn. Sections B and C were rotated each
year, but Section A remained in Japanese cane thruout the
experiment. We now have the yields of these crops for three
years, from which to draw conclusions.

JAPANESE CANE EXPERIMENT
Table No. 12 shows the kinds and amount of fertilizer applied
per acre, and Table No. 13 shows the yield in tons .of green
material, also a very satisfactory yield the first year after re-
planting, and it also shows a very decided decrease in yield the
second and third years.

SWEET POTATO EXPERIMENT
Table No. 14 shows the yield in bushels per acre of sweet
potatoes for the years 1915, 1916, and 1917, and the three year
average. The sweet potato plots were fertilized the same as the
Japanese cane plots as given in Table No. 12. This table shows
very clearly the need of potash in the fertilizer, if we are to
maintain the yield.
One of the surprises in this test is that plot II which received
no ammonia, produced such satisfactory yields each year.

TABLE 12.-FERrTZERS USED IN REPLANTING TEST, POUNDS PER ACRE

Fertilizer PLr PpLOT PLOT PLOT PLOT I PT PLOT I PLO
__I II III I IV V IVI VII VVIII
Lbs. Lbs. Lbs. L. Lbs. b b. L s.
Dried blood .............. .......... 112 ... ..... ........ 112 .......... 112 112
Sulphate of ammonia............................ 72 ........ 72 .......... ..........
Muriate of potash.............. 84 84 .......... 84 84 .......... .......... ..........
Sulphate of potash........... ......... .......... .......... ........ ..... 84 84 84
Acid phosphate .................. ...... 224 224 224 224 224 224 224
Ground limestone .............. ...... .................... ......... .......... .... ............ 2000

TABLE 13.-YIELDS OF JAPANESE CANE IN TEST, TONS GREEN MATERIAL
PER ACRE
I 1915 1916 1917
Tons Tons Tons
Plot L................................................. 29.5 21.4 .96
Plot II........................... ...... 31.9 15.6 2.16
Plot III............. ........ ..... ... 18.0 3.8 0.0
Plot IV....._......._.. ........._.... 24.2 12.5 2.4
Plot V........................... 29.7 10.6 3.7
Plot VI.................................... .. 24.9 9.6 3.7
Plot VII..................................... . 27.8 7.7 2.4
Plot VIII................ ....... . ....... 22.5 12.2 5.2






Annual Report, 1918


TABLE 14.-YIELDS OF SWEET POTATOES. BUSHELS PER ACRE
1915 1916 1917 3 year
Bushels Bushels Bushels average
Plot I................ .....- 245.6 153.6 222.4 207.2
Plot II...................... 221.6 177.6 240.0 213.0
Plot III........... ...... 99.6 86.4 72.0 86.0
Plot IV ............. 259.6 228.8 294.4 260.9
Plot V ............... 252.0 182.6 276.8 237.1
Plot VI..................... 216.0 128.0 320.0 221.3
Plot VII.................... 222.0 203.2 251.2 225.4
Plot VIII......... ....... 269.6 110.4 232.0 204.0

CORN FERTILIZER EXPERIMENT
In this experiment the corn was fertilized the same as the
Japanese cane and sweet potatoes as given in table No. 12.
The following are the yields in bushels per acre from each plot:
Plot I, 12.34; plot II, 13.71; plot III, 17.82; plot IV, 19.21; plot V,
10.97; plot VI, 17.82; plot VII, 23.31; plot VIII, 5.48.


Fig. 2.-Japanese cane growing at the Experiment Station

JAPANESE CANE FERTILIZER EXPERIMENT

This experiment was started in 1914. The results given in
table No. 15 show the amount of fertilizer applied each year, the
yield in tons of green material produced each year, and the
average yield for the four years.
This shows that plot III fertilized with barnyard manure pro-
duced the largest average yield for the four years. Plot I was


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Florida Agriulturi Er periment Station


the next highest, plot II taking third place. There is very little
or no difference in the -average yield of plots V, VI, VII, and
VIII.
TABLE 15.-JAPANEM CANE FwruaT m EXPERgOumE
Fertilizer applied, pounds per acre

oa

S I ._
e S s SYield per acre
0 r tone green mAteral


I *a I Av-
S 0 1914 1915 1916 1917 er-
1 84.................. 150 ........... 60 2000 17.08 18.30 10.85 10.02 12.80
2 .. 123.5 ......... 150.......... 60 200014.42 12.95 8.23 9.97 11.89
3 ....... .. ......... *30 ... ...................... _. 82.67 18.65 13.21 12.07 17.90
4 .... 128.5..................... 75....... 60... 12.3111.20 9.01 5.65 9.54
5 84 .................. 150 .... ..... 60.. 15.97 11.20 8.40 7.96 10.88
6 84 ...................... 75 ..... 60 ._17.1112.16 7.18 7117 10.90
7 84 ... ...................... ... 60 2000 16.8511.90 6.91 9.4510.77
8 84 ....... .... 18 60 16.68 9.86 5.60 11.20 10.71
9 9.63 7.17 3.50 6.03 658
10 84 ...... .. 200012.77 7.17 8.06 7.48 7.60
11 84 -......... 75 ... 14.38 8.31 3.85 6.68 8.80
12 -. 123 .. .......... ....... 13.41 7.00 2.01 6.12 7.18
13 .... 116. ....... 60_ 14.11 7.35 8.5011.68 9.14
14 ..... 128.5 ................. 60_. 9.02 8.22 3.33 7.17 6.93
15 84 ..................... .... 60.. 12.10 8.75 6.65 9.4A 9.23
16 .....- ................. 183 .. 9.14 7.70 3.76 4.06 6.16
17 .------.. ................... .. ... 60 9.09 7.08 3.85 8.28 65.81
18 ........ 75................ 6.79 5.42 2.63 2.45 4.2
19 --.- ........... 150...... ... 8.40 5.68 2.98 2.80 4.96
20 ................................................. ... 6.67 3.93 2.81 2.10 8.87
21 ...... 12 .5..... ............... ..... ...... ..... 7.05 6.56 2.80 3.41 4.96
22 ....... 116.6.................................. 14.08 7.78 5.25 2.88 7.48
2 84................................... 9.4 7.70 4.78 8.98 6.45


*Thirty two-horse wagon loads.

/!


Respectfully,
JOHN M. SCOTT,
Animal Industrialist.






Annual Report, 1918


REPORT OF PLANT PHYSIOLOGIST
P. H. Rolfs, Director.
SIR: I herewith submit the report of the Plant Physiologist
for the fiscal year ending June 30, 1918.
The work of the Plant Physiologist has been confined largely
to a field study of the different ratios of phosphoric acid and
potash in complete fertilizers upon the growth and yield of citrus
trees; the influence of different ratios of potash in complete fer-
tilizers upon the growth and yield of potatoes; and the compara-
tive value of different sources of phosphoric acid in complete
fertilizers upon the growth and yield of citrus trees and of pota-
toes. The field experiments with citrus trees are a continuation
of those started in previous years; the experiments with potatoes
were begun during this fiscal year.
The work of the Assistant Plant Physiologist has been confined
to a study of the structure and development of fruit buds in citrus
trees. The purpose of the study was to determine, if possible,
when fruit buds were formed in citrus stems, and the factors
that influence their development. With this information at hand,
it is thought that the citrus grower can fertilize his trees more
intelligently for the production of bearing wood and of fruit.
The Assistant Plant Physiologist has made marked progress
in her work during the year. The results show that there is a
cluster of two to four buds in the axil of every leaf; that in
mature dormant stems, the fruit buds (those that will produce
a growth of leaves, stems and flowers) can be distinguished
microscopically from the vegetative buds (those that will produce
a growth of leaves and stems only) by certain differences in the
crowns of the growing tips; and that the fruit buds are formed
and differentiated from the vegetative buds during the growth
flush while the stems are young and succulent. Both fruit buds
and vegetative buds were found in all of the mature leaf axils
examined. While the amount of material examined was not suf-
ficiently great to prove that fruit buds occur in every axil, it
does indicate that such is the case.
After the buds are formed in the young growing stems, they
go into a state of dormancy from which none to only one or two
emerge at the beginning of the next or some succeeding flush of
growth. The bud or buds emerging may be either fruit buds
or vegetative buds. In view of these facts, the problem resolves
itself into a study of the factors which influence the dormancy of
the buds and determine which kind of bud will develop. Appar-


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Florida Agricultural Experiment Station


ently there are two factors which influence them. The one is
environmental, which includes the influence of fertilizer treat-
ment; and the second is that of inheritance.
The present studies contemplate only a study of the environ-
mental factors with a view of determining to what extent fruit
bud development can be influenced by fertilizer treatment.

FIELD EXPERIMENTS WITH FERTILIZERS
EXPERIMENTS WITH POTATOES
EXPERIMENT TO DETERMINE THE POTASH REQUIREMENTS OF POTATOES
Since 1914, when the supply of German potash was cut off and
the price of this commodity began to rise, one of the problems
confronting the potato growers of Florida has been how little
potash can be used in the fertilizers without decreasing the
quality and yield of the crops. At first, it was feared that a
marked injury to the shipping quality of the potatoes and a
decrease in yield would result. But at the end of the season, no
ill effects were found that could be proven to be due to the lack
of this element.
In succeeding seasons, no general decrease in yield has been
observed, but in some cases, the potatoes have not carried well.
Some have assumed this to be due to lack of sufficient potash
in the fertilizers, but there is no proof for the assumption. It
may have been due to some one or more of the many other factors
that influence the growth of the potato.
There are two conditions that probably have bearing upon the
possibility of the crop from certain fields having been effected
detrimentally. If the field was an old one where the soil had
received repeated applications of fertilizer containing an average
to large amounts of potash, the work of Collison (Fla. Agr. Exp.
Sta. Ann. Reports, 1912 to 1917) and others indicates that
probably sufficient amounts were stored in the soil to supply the
needs of several succeeding crops. On the other hand, if the
field was new and the soil virgin, repeated analyses of Florida
soils has shown that it did not contain sufficient potash to produce
the best yield. It is uncertain whether this lack of potash is
sufficient to effect the quality of the tubers.
Experimental
During the fiscal year, the opportunity was offered this Labo-
ratory by F. M. Leonard of the Wetumpka Fruit Company of
Hastings, Fla., to carry out a field experiment with potatoes


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Annual Report, 1918


planted on virgin soils. The purpose of the experiment was to
study the influence of various amounts of potash in the complete
fertilizers on the growth and yield of the crop.
The land upon which the fertilizer experiment was carried out
was the level flatwoods typical to the Hastings section. The ex-
periment was located on part of a large tract that had been
cleared less than a year. The soil was that classified by the
United States Department of Agriculture as Norfolk sandy loam,
and was underlain with clay at a depth of about three feet.
The tract was laid off in east and west beds about 37 feet in
width. The beds were separated by shallow ditches that con-
nected with deeper ditches at the ends. These ditches served for
both irrigation and drainage. The potatoes were planted in
mounds about 14 inches high and 40 inches apart, running
lengthwise of the beds. An artesian well near the southwest
corner of the tract furnished water for irrigation.
Plots
The experiment was carried out on the east half of the first
seven beds on the south side of this tract. The area included
in the experiment was about 31/2 acres. The beds included were
divided into tenth acre plots. There were five plots to each bed
or 35 in all. (Fig. 3.)
Fertilizers Used
Numbering from the south, all plots included on the odd beds
received a fertilizer containing a full ration of ammonia and
phosphoric acid, but no potash. The plots on the even beds
received complete fertilizers containing 1%, 3% and 5% of
potash respectively, each fertilizer being used on five different
plots. Thus each plot receiving a potash fertilizer was flanked
on each side by a plot that received none. (Fig. 3.)
The fertilizers used were mixed at the factory by machinery
and applied by hand in the furrows on February 1, 1918. A
sand filler was used in mixing them so that equivalent weights
contained the same amounts of plant food. They were applied
at the rate of 1700 pounds to the acre. Only one application was
made during the season. The constitution of the fertilizers was
as follows: See Tables 16, 17, 18, and 19.


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Florida Agricultural Experiment Station
TABLE 16.-ANALYsIs O FmRTu JE ON 1% POTrsa PLOTS


AMMONIA POTASH AV. PaO. ToTAL







500 High Grade
Tankage .110.84 2.71 -... 2. .6 4 10
75 Nebraska ......................
Potash .......8.00 .0.............................. ... ....
860 Acid
Phosphate ........... ......... ... 17.57 7.52 118.20 7.82
365 Sand Filler. ......... .......... ..... ..... ... ........ I.----............
2000 1............ 15.23 1............ 11.05 1............ 18.13 i............ 19.02
TABLE 17.-ANALYSIS OF FERTILIZE ON 3% POTASH PLOTS

AMMONIA POTASH Av. PHOS. TOTAL
SAC .D PH O. ACID



Ammonia 2524% 2.52% ....
860 Acid 5 .
I__S. CO 0 W_ CO < 6O
2 Sulphate of
Ammonia .. 25.24% 2.52. .. ......................... 17 ......... 18.......... 82
500 High Grade ........






AMM0omo POrASa AV.APos. Ts A
Tankage .... 10.84 2.71 ................. 2.45% .61% 4.80% 1.20%9
225 Nebraska
Potash ...... ......... ........ 28.00% 3.15% ............ .....................
860 Acid
Phosphate ................................. 17.57 7.52 18.20 7.82
215 Sand Filler ........ ....... ........ .. ...... .... ....... ....... .... ....
2000 I 1............ 5.23 ............ 13.15 ... 8. 13 I....... 9.02
TABLE 18.-ANALYSIS OF FEIrUIZEn ON 5% POTASH PLOTS



WI be b be e 1

o 0 a a S

200 Sulphate of
Ammonia 25.24% 2.62%............ ......... ............ ....... ... ..........
500 High Grade
Tankage .... 10.84 2.71 ............ .......... 2.45% .61% 4.80% 1.20%
375 Nebraska
Potash ................... ..........28.00%5.25% ...... .... .......... ....
860 Acid
Phosphate .- .......- ...- 17.57 7.52 1820 7.82
65 SandFiler_ _:...I...... ......
2000 __1__... 6.23.....-2 -S..- 18.13 ...9.02
















PHOSPHATE EXPERIMENT


POTASH EXPERIMENT


Fig. 3.-Experiments with potatoes at Hastings
All plots in the Phosphate Experiment were given a uniform ammonia and potash treatment.
Those in the Potash Experiment were given a uniform ammonia and phosphoric acid treatment.


A-Acid phosphate plots.
S-Soft phosphate plots.
P-Pebble phosphate plots.
Blank-No phosphoric acid plots.


1%K--Fertilizer containing 1% potash.
3%K-Fertilizer containing 3% potash.
5%K-Fertilizer containing 5% potash.
Blank-Fertilizer containing no potash.


p A S P A -N /7 K /7n

A ~ P A 35 //f j/lF IZK 3,





Florida Agricultural Experiment Station


TABLE 19.-ANALYSIS OF FERTILIZER ON PLOTS WrEBE NO POTASH
WAS USED

AMMONIA POTASH Av cm PPOS TOAc
AMMONA POASc PHOS. ACID



2 3 .

200 Sulphate of
Ammonia .. 25.24% 2.52% ......... ... .... ......
500 High Grade
Tankage .... 10.84 2.71 ............ ......... 2.45% .61 4.80% 1.20
860 Acid
Phosphate .. ............ ....... ........... 17.57 7.52 18.20 7.82
440 Sand Filler ......... ......... ............. .......... .. .... ..
2000 I 1............ 15.23 I............ None ............ |8.13 ............ 19.02
Planting
The potatoes used were Spaulding Rose No. 4, and were grown
on a plantation in Maine. The potatoes were fairly uniform in
size and condition. They were not treated before planting.
They were planted on February 18 and 19, 1918 by means of a
planter that dropped them about 10 to 12 inches apart in the
row.
Irrigation
Moisture conditions in the field during the growing season
were quite variable. Owing to a drought late in February, it was
necessary to irrigate the fields, while on March 6, April 8, and
May 14 heavy rains fell, flooding the field and doing some damage
in the lowest spots.
Cultivation and Spraying
The field was given the usual cultivation to keep the soil well
aerated. The plants were sprayed repeatedly with bordeaux
mixture to prevent late blight.

Results
The stand of plants was uniform in all plots regardless of
treatment. No marked differences were evident at any time
during the season, between the plants fertilized with potash
and those receiving no potash.
The potatoes were harvested on May 27 to 29. The vines
were all dead at that time. They were dug by means of a digging
machine, gathered by hand, placed in crates and taken to the
packing shed where they were graded by machine. Four dif-


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Annual Report, 1918


ferent grades were made. The first two correspond closely to
the Government grades. On the basis of weight, the different
grades average as follows:

No. 1............................... 6 potatoes in a pound
No. 2..... ................ ..........11 potatoes in a pound
No. 3..... .............................19 potatoes in a pound
No. 4..... ..............................35 potatoes in a pound

Table No. 20 shows the potash treatment and the yield of
the different plots in pounds and by grades as compared with
the plots that received no potash treatment. The experiment
is to be repeated during the coming year in the same loca-
tion and with the same arrangement of plots. Therefore no dis-
cussion of the data will be given at this time.

Influence of Treatments Upon Cover Crop Growth
After the potatoes were harvested, the mounds were leveled
and the beds planted to cowpeas by broadcasting. The peas made
an excellent growth of vines on all plots. No difference in height
or stand between the vines on plots receiving potash and those
without potash was evident to the eye. Unfortunately it was
not possible to get a quantitative measure of the amount of seed
and of hay produced on the different plots.

TABLE 20.-YELD IN POUNDS AND BY GRADES OF POTASH AND ADJACENT
No POTASH TENTH-ACRE PLOTS

I No POTASH I 1% POTASH NO POTASH
Grades ................ 1 2 3 4 1 2 3 4 1 2 3 4
89 46 27 19 209 73 30 11 51 35 18 14
115 80 39 26 204 76 38 23 113 58 35 21
64 33 17 13 276 91 32 18 155 74 30 16
124 70 30 14 199 83 34 11 81 53 28 17
86 62 36 24 128 79 34 24 117 58 38 26
Total .................. 4781 291 149 961016 402 168 87 517 278 149 94
Average ............ 96 581 30 19 203| 80 34 17 103 56 30 19
Average of the two No Potash plots....................................99 57 30 19

i No POTASH I 3% POTASH O No POTASH
Grades .......... 1 2 3 4 1 2 3 4 1 2 3 4
43 46 21 17 367 98 34 14 63 52 28 19
51 35 18 14 293 91 37 18 48 37 20 18
113 58 35 21 282 72 32 18 138 66 36 19
155 74 30 16 195 104 35 19 74 45 27 23
81 53 28 17 182 87 38 20 210 85 33 17
Total ..................443 266 132 851319 452 176 89 533 285 144 91
Average .............. 89 53 26 17 264 90 35 18 107 57 29 18
Average of the two N Potash pots................................ 98 55 28 18


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Florida Agricultural Experiment Station


I No POTASH 65% PoTAsa I No POTASH


63 52 28 19 339 95 41 19 86 62 36 24
48 37 20 13 168 54 46 21 200 84 40 19
138 66 36 19 120 67 35 20 204 88 44 20
Total .................... 459 274 140 871418 406 176 82 678 337 167 90
Average ............ 92 55 28 17 284 81 35 16 136 67 33 18
Average of the two No Potash pLots ........................... .... 114 61 31 18

EXPERIMENTS TO DETERMINE THE RELATIVE VALUE OF DIFFERENT SOURCES
OP POSPHORIC ACID IN COMPLETE FERTILIZERS FOR POTATOES
For a number of years there has been much contention among
farmers as to the relative value of the raw phosphates as sources
of phosphoric acid for crops grown on Florida soils. Some
have contended that these phosphates, when added to their
soils, became available in sufficient amounts to supply the needs
of their crops; and that they were economical sources to use.
Others have denied this contention. Late in 1917, F. M. Leonard
of the Wetumpka Fruit Company of Hastings, Fla., placed 31h
acres and the facilities of the company's plantation at the com-
mand of this laboratory for carrying on an experiment to study
the degree of availability of different sources of phosphoric acid
in the soil as indicated by the growth and yield of potatoes.

Experimental
The field assigned for the experiment was immediately to the
west of the one where the experiment to determine the potash
requirements of potatoes was located. (Fig. 3.) It consisted
of the west halves of the beds used in that experiment. Thus
the beds and rows of the two experiments were continuous.
There was very little difference in the soil conditions in the two
fields.
Plots
The area included in the experiment was about 31 acres. The
beds were divided into one tenth acre plots, making five plots
to each bed and thirty-five plots in all. (Fig. 3.)

Fertilizer Used
Numbering from the south side of the field, the odd beds were
given a mixed fertilizer containing a full ration of ammonia and
potash, but with practically no phosphoric acid. While no source
of phosphoric acid was included in the mixture, some of the


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Annual Report, 1918


sources of ammonia used contained small amounts of phos-
phoric acid, so that the mixture contained less than 1% of phos-
phoric acid. (See tables 21 and 22.)
The even beds were given fertilizers containing a complete
ration of ammonia, phosphoric acid and potash, but differing in
the source of phosphoric acid used in the mixture. (Fig. 3.)
The sources of phosphoric acid used were acid phosphate and
the two raw or untreated phosphates-finely ground pebble phos-
phate rock, and soft phosphate.
Two applications of fertilizers were given. Those containing
practically no phosphoric acid and those containing acid phos-
phate were applied on February 1, 1918. They were factory
mixed and contained a sufficient amount of sand filler to make
equal weights contain equivalent amounts of plant food. They
were applied by hand at the rate of 1700 pounds per acre.
The raw phosphates were applied separately, and on December
6, 1917. This gave them time to be acted upon by the soil pro-
cesses before the crop was planted. It happened, however, that
there was very little rain and very little moisture in the soil, so
it is probable that they remained in the soil in practically the
same form in which they were applied, until the land was irri-
gated in February.
Acid Phosphate Plots.-The mixed fertilizer containing acid
phosphate as the source of phosphoric acid was used on five of
the plots on the even beds. (Fig. 3.)
Raw Phosphate Plots.-The remaining ten plots on the even
beds were given the mixed fertilizer containing practically no
phosphoric acid. They received in addition (and applied sep-
arately on December 6, 1917) an amount of phosphoric acid
equivalent to three times that carried in the acid phosphate ferti-
lizer. On five of the plots, the phosphoric acid was carried in the
form of finely ground pebble phosphate rock; and on the other
five, as soft phosphate. (Fig. 3.)
The constitution of the mixed fertilizers used in this experi-
ment was as follows:


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Florida Agricultural Experiment Station


TABLE 21.-ANALYSIS OF FmsaTtUza USED ON PLOTS CONTAINING NO
PHOSPHonic ACID

AMMONIA POTASH Av. Pnos. ToTAL
I L AcI PHOs. AcID




a< V w C < COO
200 Sulphate of
Ammonia 25.24% 2.52% ...... .. ..... ....... .... ..... .. ..
200 Fine Gr. To-
bacco stems 2.79 .28 7.30% .73% ......- ......................
200 High Grade
Tankage .... 10.84 1.08 ..................... 2.45% .24% 4.80% .48%
400 Bright
Cottonseed
Meal ............1 7.19 1.44 1.82 .36 2.37 .47 2.55 .51
100 Nebraska
Potash .... ........ ...... 28.00 1.40 ............ ......... ............ .......
900 Sand Filler .......... ......... .......... .......... .......... .... .......
2000 1 1............ 15.32 1....._..... 2.49 I...... .71 ............ i .99
TABLE 22.- ANALYSIS or FERTILIZEf USED ON PLOTS CONTAINING
ACID PHOSPHATE

AMMONIA POTASH Av. PHOS. TOTAL




55 a be b a t t
200 Sulphate of
Ammonia .. 25.24% 2.52% ..... ........... ........................... ........
200 Fine Gr. To-
bacco stems 2.79 .28 7.30% .73% ............ ...........................
200 High Grade
Tankage .... 10.84 1.08 .................. 2.46% .24% 4.80% .48%
400 Bright
Cotton Seed
Meal ........ 7.19 1.44 1.82 .36 2.87 .47 2.55 .51
100 Nebraska
Potash ........ .... ........ 28.00 1.40 ........ ... ..... ............ .
860 Acid
Phosphate ...........17.57 7.52 18.20 7.82
40 Sand Filler I............ .......... ........... ............ ..... ... .. ...
2000 1 1........ 1.32 .......... 12.49 I............ 8.23 ........... 18.81

Planting
The potatoes used were Spaulding Rose No. 4. They were not
treated and were planted at the same time and in the same man-
ner as those in the potash experiment.






Annual Report, 1918


Irrigation
The moisture conditions in this field were practically the same
as those in the potash experimental field. The two fields were
irrigated at the same time.
Cultivation and Spraying
The field was cultivated and sprayed at the same time and in
the same manner as the potash experimental field.
Results
Very few chemical studies were carried out in this experiment
to determine the solubility of the different sources of phosphoric
acid after they were added to the soil. The availability of these
materials was measured entirely by their influence upon the
growth and yield of the plants.
Effect Upon Growth.-Unfortunately no quantitative record
of this phase of the work was obtained. The following descrip-
tions are based upon general notes made at intervals during the
growing season.
The materials differed markedly in their influence upon the
growth of the plants. In the plots that received no phosphate
and those that received the raw phosphates, the growth from the
tubers was very irregular, giving a poor stand. Late in the
season, plants here and there were just breaking thru the ground.
After the plants became independent of the tubers, the growth
was slow. After a period of several weeks, the plants in the raw
phosphate plots increased rapidly in size, but by the end of the
season had not become quite as large as those in the acid phos-
phate plots. In the plots which received no phosphate the plants
made slow growth thru the entire season. At the end of the
growing season, they averaged fully 50% smaller in size than
those in the acid phosphate plots. The character of the growth
was also different. The leaves were somewhat undersized, and
the internodes of the stems were longer. The plants had a
rather stiff upright appearance. Early in the season, their
color was slightly yellowish; later, it became a deep green.
The plants in the plots where no phosphate was used were slow
in maturing. At the end of the season, the majority of the plants
were still alive and making some growth, while the tops in the
other plots were all dead.
Influence Upon Yield.-The potatoes in the experiment were
harvested May 27 to 29, and graded in the same manner as those


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Florida Agricultural Experiment Station


in the potash experiment. Table 23 shows the yields of the dif-
ferent plots in pounds and by grades. The yields of the dif-
ferent plots receiving phosphoric acid are compared with the
adjacent plots that received no phosphoric acid.
Influence of Treatment Upon Cover Growth.-After the pota-
toes were harvested, the field was plowed, harrowed, and peas
planted by broadcasting. The peas made a nice and uniform
growth over all plots that had received phosphate, regardless
of the source applied. The cowpeas on the plots receiving no
phosphate grew very much like the potatoes on these plots.
When the plants became independent of the seed, the growth
became slow and continued slow thruout the season. At the end
of the season, the vines were only from 50% to 60% as high as
those on the phosphate plots.
The same differences in color and maturity that were noticed
in the potatoes, were present in the cowpeas. The vines were
slightly yellowish early in the season, but of a normal green later.
When the vines were all dead on the phosphate plots, many were
still alive and making growth on the plots which had received
no phosphate.

TABLE 23.-YIELDS IN POUNDS AND BY GRADES OF THE PHOSPHATE AND
No PHOSPHATE TENTH-ACRE PLOTS

I No PHOSPHATE I Acm PHOSPHATE ( No PHOSPHATE
Grades ......... ..... 1 2 3 4 1 2 3 4 1 2 3 4
36 36 23 33 94 59 35 30 10 21 19 26
118 67 29 13 387 93 36 21 88 54 40 23
113 58 17 18 250 93 33 16 65 46 25 18
46 47 33 30 258 91 40 21 34 40 28 25
39 34 25 26 155 73 40 8 22 24 12 28
Total .................... 352 242 127 120 1144 409 184 96 219 185 124 120
Average .............. 70 4 25 24 229 82 37 19 44 3725 24
Average of the two No Phosphate plots ............................ 57 43 25 24


No PHOSPHATE PEBBLE PHOSPHATEi NO PHOSPHATE
Grades .......... 1 2 3 4 1 2 3 4 1 2 3 4
118 731 36 23 157 88 47 35 46 47 33 30
162 831 31 20 225 87 40 23 113 58 17 18
66 48, 32 34 173 83 49 36 39 34 25 26
S256 32' 25 25 101 65 40 32 28 39 33 36
651 33 21 20 66 51 34 28 6 11 15 18
Total -..------..-...- 436 269 145 122 722 374 210 154 232 189 123 128
Average ........... 871 54 29 24 144 75 42 31 46 38 25 26
Average of the two No Phosphate plots..................... 67' 46 27 25


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No PHOSPHATE Sorr PHOSPHATE No PHOSPHATE
Grades ............. 1 2 3 4 1 21 3 4 1 2 3 4
I 68! 47 321 301 116 67 37 29 66 48 32 34
j 10i 21 19 261 99 621 46 34 25 32 25 25
88 54 40 23; 144: 62 33 25 65 33 21 20
| 34 40 28, 25i 89 64 39 30 61 50 32J 27
65j 46, 25; 18 701 531 39 26 21 31 33 21
Total ..................... 2651| 208' 1441 122 5181 308' 194 144i 238 194 143 127
Average ........... 37, 42 29 24 1041 621 39 29 48 39 29 26
Average of the two No Phosphate plots................... 51 40 29 25

EXPERIMENTS WITH CITRUS TREES
EXPERIMENTS TO DETERMINE THE RELATIVE VALUE OF DIFFERENT SOURCES
OF PHOSPHORIC ACID IN COMPLETE FERTILIZERS FOR CITRUS TREES
There has been the same contention between the citrus fruit
growers in Florida as between the general farmers in reference
to the advisability of using the raw phosphates as fertilizer
sources to supply the phosphoric acid needs. Some have used
them with apparently good results; while others apparently did
not obtain good results, hence condemn the practice strongly. It
has been apparent from the beginning that the question could be
decided only by some well planned field experiments conducted
on the different soil types on which citrus trees are grown in
Florida.
It is only recently that the Experiment Station has had oppor-
tunity to carry out any such experiments. Those being carried
on at present are in groves near Lake Alfred and Lowell, Fla.
The experiments at Lake Alfred are on the high pine land soil
typical of that section; the one at Lowell is on a high hammock
soil that varies from a sandy clay loam to sandy loam, rather
closely underlain with clay.
There are two experiments at Lake Alfred. One is with young
trees planted on virgin soil; the other is with young trees that
had been fertilized with complete commercial fertilizer during
the two years previous to the time the experiment was started.
The experiment at Lowell is with large bearing trees that are
more than twenty-five years of age and have always been well
fertilized.
The sources of phosphoric acid used in these experiments are
fine ground steamed bone, acid phosphate, and the two raw or
untreated phosphates-fine ground pebble phosphate rock and
soft phosphate. It was not possible to include check plots to
be given no phosphoric acid at all, therefore the acid phosphate
plots are used as the basis for comparisons.


39R





40R


Florida Agricultural Experiment Station


Experiment with Young Trees Planted on Virgin Land at Lake Alfred
This experiment was made possible thru the generosity of the
Florida Fruitlands Company. A young grove that had just been
planted was placed at the disposal of this laboratory for carrying
out the experiment. The grove was located about one mile north
of the town of Lake Alfred. It is planted on a tract of land that
slopes westward to a swamp bordering Alfred Lake. The soil
is a high pine land soil typical of this section of Florida. It is a
loose sandy soil that probably belongs to the Norfolk series.
The grove was planted in January 1917, and is composed of
270 Walters grapefruit trees on rough lemon stock, located on
the upper part of the slope; 60 Valencia oranges on sour stock,
on the lowest part of the slope and next to the swamp; and 110
Valencia oranges on rough lemon stock located between the block
of oranges on sour stock and grapefruit. (Fig. 4.)
The land upon which the grove was planted was virgin, and
had been cleared about one year previous to planting. Following
the planting, the trees were given one quarter of a pound of a
commercial fertilizer in June. This was the only fertilizer the
trees received previous to the time the experiment was started
in November, 1917.
PLOTS
The grove was divided into nine plots. The dividing lines
ran east and west with the slope, so that each plot included both


i
,
I I i 'I II
*I I I I
I t I
)11 1 ''
I I I
I I I I I I t

I I I I I
SI (
I I ( I
I I
I *I I I I I
I I I I I

EXPERIMENT ON LAND WITH
PREVIOUS FERTILIZER
TREATMENT


I i
I I I 3
I I
i I t g Ii I
j I I I
I I I I I
I I
I I I
AIBI : P'C'AK '
S \
I I ; I
I I i !


SI I I
I SI p
I I I I I


EXPERIMENT ON VIRGIN LAND


Fig. 4.-Phosphate experiments at Lake Alfred, Fla.


A-Acid phosphate.
B-Steamed bone.
S-Soft phosphate.


P-Pebble phosphate.
C-Commercial fertilizer.





Annual Report, 1918


orange and grapefruit trees. The dividing line consisted of a
row of trees, half of which received the same fertilizer treatment
as the trees in the adjacent plots. The trees in this row are
known as buffer trees. One of the plots is given a commercial
fertilizer in which the sources are mixed in an unknown pro-
portion. This plot is not considered to be a part of the experi-
ment. The remaining eight plots differ in the amount and source
of phosphoric acid contained in the fertilizer for these plots. In
two plots, the source of phosphoric acid in the fertilizer is fine
ground steamed bone; in two, acid phosphate; in two, fine
ground pebble phosphate rock; and in the remaining two, soft
phosphate. Thus each source of phosphoric acid is used in dupli-
cate. Table 24 shows the order of the plots and number of trees
in each, beginning on the south. (See Fig. 4.)
TABLE 24
Grapefruit on Valencia Valencia
Plot R. Lemon Oranges on R. Oranges on
Stock Lemon Stock Sour Stock
Acid phosphate ................ 36 trees 16 trees 8 trees
Buffer row ................... 9 4 2
Steamed bone ..... ........ 27 12 8
Buffer row................... .... 9 4 3
Soft phosphate ............. 27 12 9 "
Buffer row................... 9 "4 3
Pebble phosphate ............ 27 12 9
Buffer row......................... 9 4 3
Commercial fertilizer .... 18 8 6
Buffer row.......................... 9 4 3
Acid phosphate ............... 18 8 3 "
Buffer row ....................... 9 4 1 "
Soft phosphate ............ 18 8 2 "
Buffer row .................. 9 4 0 "
Steamed bone .................... 27 5 0
Buffer row .................. 9 0 0 "
Pebble phosphate ............ 26 0 0 "
FERTILIZERS USED
The usual practice of mixing the fertilizer in bulk and apply-
ing a given number of pounds of the mixture to each tree was
not carried out here. Instead, the fertilizer sources were
weighed and mixed for each tree separately.
The amount of fertilizer applied at each application during
the years 1917 and 1918 is based upon a theoretical application
of one pound per tree of a mixed fertilizer. For use in the spring
this fertilizer analyzed 4% ammonia, but carried no phosphoric
acid or potash; for use in summer and fall it analyzed 3%
ammonia and 8% available phosphoric acid, but contained no
potash.


41R





Florida Agricultural Experiment Station


The amount of ammonia actually applied at any one applica-
tion is uniform for all of the plots; the amount of phosphoric
acid varies according to the source in which it is carried.
The fertilizers are applied in February, June and October of
each year. No potash has been used in any of the fertilizers
thus far.
In February, no phosphoric acid is applied. Ammonia alone
is used. Each tree in every plot is given .04 of a pound of am-
monia, one half of which is carried as nitrate of soda, and the
other half as sulphate of ammonia.
In June and October, the ammonia and phosphoric acid are
applied as follows:
Steamed Bone Plots: The trees in these plots are each given
.16 of a pound of total phosphoric acid at each application, car-
ried as fine ground steamed bone. This amount is determined by
the assumption that one half of the total phosphoric acid in the
steamed bone is available.
Each tree in these plots receives in addition .03 of a pound
of ammonia. Allowance is made for the amount of ammonia that
is contained in the steamed bone, and the remainder is applied
in the form of sulphate of ammonia.
Acid Phosphate Plots: Each tree in these plots is given .08
of a pound of available phosphoric acid in the form af acid
phosphate. Each tree also receives .03 of a pound of ammonia.
An amount of this ammonia equivalent to that in the steamed
bone contained in the fertilizer given the trees in the steamed
bone plots, is applied in the form of dried blood. The remainder
is applied in the form of sulphate of ammonia.
Raw Phosphate Plots: Each tree in these plots is given .32
of a pound of total phosphoric acid. The pebble phosphate plots
receive it in the form of fine ground pebble phosphate rock; the
soft phosphate plots, in the form of soft phosphate. The amount
of phosphoric acid applied to the trees in these plots is deter-
mined on a money basis. At the time that the experiment was
started, the cost of the raw phosphates was equal to about one
fourth the cost of the soluble phosphates.
Each tree in these plots received .03 of a pound of ammonia
at each application. A part of this equivalent to that in the
steamed bone contained in the fertilizer given the steamed bone


42R






Annual Report, 1918


plots, was applied in the form of dried blood. The remainder
was applied in the form of sulphate of ammonia.
CULTIVATION AND COVER CROP
The cultivation given the trees consists of shallow plowing in
the early spring and the maintenance of a dust mulch until
early summer when the rains begin. At this time the grove is
laid by with the exception of a narrow strip on each side of the
tree rows which is kept cultivated by means of an Acme harrow.
The middles are planted to beggarweed. In the fall, the cover
crop is cut and allowed to remain on the ground.
SPRAYING
The trees are sprayed whenever necessary for the control of
insect pests and of citrus scab.
RESULTS
The trees in the experiment have all made a normal growth.
The foliage and stem growth has been of good size and color.
No differences in appearance have become evident in any of
the trees. On November 3, 1917, the diameters of the trunks
of the trees, six inches above the bud union, were measured as a
basis for keeping a record of the increased growth induced by
the different treatments. A second measurement has not yet
been made.
Experiment with Young Trees that Have Received Previous Fertilizer
Treatment
The purpose of this experiment is to study the influence of
a previous fertilizer treatment of the soil upon the availability
of the different sources of phosphoric acid as measured by tree
growth and yield. The experiment is being carried out with a
block of trees immediately to the south of the experiment with
young trees on virgin land. (Fig. 4.) The rows of the two
experiments are continuous. The lay of the land and the char-
acter of the soil is practically the same.
The block consists of 234 Walters grapefruit on rough lemon
stock on the upper slope, and 158 Lue Gim Gong oranges on
sour stock on the lower slope. The trees were planted in March
1914 and were one year buds on two year stocks at planting.
The experiment with these trees was started at the same time
as that on the virgin land. Thus the trees were about three
years of age at the time the experiment began in November 1917.


43R





Florida Agricultural Experiment Station


PREVIOUS FERTILIZER TREATMENT
Until the experiment was started, the trees had been given
regular applications of a complete commercial fertilizer three
times during each year. The sources of the phosphoric acid in
this fertilizer were not named specifically upon the tag, but.were
stated to be of an organic nature.
PLOTS AND FERTILIZERS USED
This experiment is an exact duplication of the experiment with
young trees planted on virgin land. There are nine plots, one
of which receives a commercial fertilizer similar to the one used
previous to the time the experiment was started. The plot
treatments, arrangement of the plots, cultivation and spraying
are the same as those in the experiment on virgin land, differing
only in the amount of fertilizer given each tree. The arrange-
ment of the plots and the number of trees in each are as follows:

TABLE 25
Grapefruit on Lue Gim Gong
Plot Rough Lemon Oranges on Sour
I Stock Stock
Acid phosphate .............................. 27 trees 20 trees
Buffer row ....................................... 9 6 "
Steamed bone .................................. 18 12 "
Buffer row ....................................... 9 6 "
Soft phosphate ................ ........... 18 12
Buffer row ......... ......................... 9 6
Pebble phosphate ....... .................. 18 12
Commercial fertilizer ...............-. 18 12
Acid phosphate ......................... 18 12
Buffer row .................................... 9 6
Soft phosphate ............................. 18 12
Buffer row ...........................9 6
Steamed bone ............................... 18 12 "
Buffer row ................................ 9 6 "
Pebble phosphate .........................! 27 18 "

The fertilizer sources are weighed and mixed for each tree
separately. The amount of fertilizer given each tree during
1917 and 1918 was based upon a theoretical application of four
pounds of a mixed fertilizer analyzing 4% ammonia for the
spring application; and 3% ammonia and 8% available phos-
phoric acid for the summer and fall applications. Thus each
tree in the experiment received .16 of a pound of ammonia car-
ried as nitrate of soda and sulphate of ammonia in the spring
season; and .12 of a pound in the summer and in the fall. The
trees in the different plots received the following amounts of
phosphoric acid per tree in the summer and in the fall:


44R






Annual Report, 1918


Acid phosphate plots.................... .32 lb. Available P. A.
Steamed bone plots........................ .64 lb. Total P. A.
Soft phosphate plots.......................1.28 lbs. Total P. A.
Pebble phosphate plots.................1.28 Ibs. Total P. A.
RESULTS
The trees have made a uniform and normal growth. No dif-
ferences have become evident that can be attributed to the fer-
tilizer treatment. The trees bloomed and set some fruit this
spring. The amount, however, is small, as the trees are just
coming into bearing.
On November 19, the diameters of the trunks of the trees
were measured at a point six inches above the bud union. This
is used as a basis for determining the increase in diameters due
to the influence of the soil treatments upon growth. The second
measurements have not yet been made.
Experiments with Bearing Trees at Lowell
This experiment is being carried out on the property of the
Wetumpka Fruit Company at Lowell, Fla. There are more than
eighty acres planted in orange trees, all of which are included
in this experiment. The trees are grouped in five different
groves known as the Montague Grove, the East Lot, the Morrell
Lot, the Home Grove, and the New Clearing Grove. (Fig. 5.)
The groves are planted on the rolling high hammock land
characteristic of this section. The soil varies from a sandy clay
loam to a sandy loam underlain with clay.
The trees are oranges of unknown variety budded on sour
stock, and are more than 25 years of age. They were planted
from a nursery located on the property. They have always been
well cared for and well fertilized with complete fertilizers. It
is therefore probable that there were considerable amounts of
phosphoric acid and potash stored in the soil at the beginning
of this experiment.
The experiment was started in the spring of 1917. On Feb-
ruary 1, 1917, the grove was severely cut back by the cold, and a
number of trees were killed. Despite this fact, the experiment
was continued on the basis that the degree of recovery of the
trees would determine in a measure the degree of availability of
the different phosphates used.
FERTILIZERS USED
The same sources of phosphoric acid were used in this experi-
ment as in the groves at Lake Alfred. They were fine ground


45R





Florida Agricultural Experimcnt Station


as substitutes, and on one plot ground limestone was applied in
addition to the given source of phosphoric acid. As stated above,
all groves were given a uniform ammonia treatment and no
potash.
The fifth grove was divided into four large plots, all of which
were given ground limestone. The plots differed in the source
of phosphoric acid which they received.
A sixth block, consisting of the halves of two of the above
groves, was not plotted. The whole block was given the same
amount of plant food as the other groves, but differed in that
its phosphoric acid was carried in the form of two sources-
acid phosphate and steamed bone. The constitution of this fer-
tilizer was practically the same as that of the fertilizer which
was used on all of the groves prior to the time the experiment
was started.
Except in the fifth grove, the plots consisted of three rows
extending entirely across the grove, and were separated by a
row of buffer trees. A buffer tree is one whose halves receive
the same fertilizer treatment as the trees in the adjacent plots.
The purpose of this arrangement was to compare the plot
treatments on trees growing under practically the same soil
conditions, and to have them in replicate. By this plan, each of
the phosphoric acid treatments were repeated four times, and
each of these treatments were given two applications of ground
limestone.
Wherever possible, the plots extended in the same direction
as the slopes.
With the exception of the raw phosphates, all fertilizer
sources were factory mixed. The raw phosphates were applied
separately at about the same time that the mixed fertilizers
were applied. Only one application of ground limestone has
been made in the groves. This was given in July 1917 at the
rate of two tons to each acre.
MONTAGE GROVE
The source of phosphoric acid used in the fertilizer for the
trees in the Montague grove was soft phosphate, except in the fer-
tilizer for three plots in the middle of the grove. In one plot,
pebble phosphate was substituted for soft phosphate; in another,
acid phosphate was substituted, and in the third, steamed bone.
A fourth plot was included, to which ground limestone was
applied in addition to the fertilizer. (See Fig. 5.)


48R






Annual Report, 1918


monia and 8% or more of available phosphoric acid. After the
freeze, the trees were very irregular in size. Some had been
killed entirely to the ground and sour sprouts were being put
out from the stock. Others were alive above the bud union,
but were not of sufficient size to bear fruit. The remainder
varied in size from this to trees of practically the original size
before the freeze. However, very few were of the original size.
For the purpose of more easily figuring the fertilizer require-
ments of the grove, a plan was adopted whereby the condition
and size of each tree was rated in units. A 1-unit tree was one
that was alive above the bud union, but without sufficient top
to bear fruit. A 2-unit tree was one of sufficient size to bear
from a few fruits to a box of fruit. A 3-unit tree was one that
would bear from one to three boxes of fruit. A 4-unit tree was
one of the original size before the freeze and would bear three
to five boxes or more of fruit.
A 1-unit tree was given a fourth pound of ammonia and an
amount of phosphoric acid that varied according to the follow-
ing conditions:
One half pound of available phosphoric acid where acid phos-
phate was the only source of phosphoric acid used;
Or, one half pound of available phosphoric acid where acid
phosphate and steamed bone were used together as the sources,
assuming that one half of the total phosphoric acid in steamed
bone was available;
Or, one pound of total phosphoric acid where steamed bone was
the only source of phosphoric acid used;
Or, two pounds of total phosphoric acid where soft phosphate
or pebble phosphate was the only source used.
A 2-unit tree was given twice the amount of ammonia and
phosphoric acid given a 1-unit tree; a 3-unit tree, three times;
and a 4-unit tree, four times that amount.
The ground limestone used in the grove was applied on the
acre basis. It was broadcasted from tree to tree at the rate of
two tons to each acre.
PLOTS
Four of the groves included in this experiment were plotted
on the basis of fertilizing each grove or a part of it, with a
given source of phosphoric acid with the exception of four plots.
On three of the plots other sources of phosphoric acid were used


47R




Florida Agricultural Experiment Station


as substitutes, and on one plot ground limestone was applied in
addition to the given source of phosphoric acid. As stated above,
all groves were given a uniform ammonia treatment and no
potash.
The fifth grove was divided into four large plots, all of which
were given ground limestone. The plots differed in the source
of phosphoric acid which they received.
A sixth block, consisting of the halves of two of the above
groves, was not plotted. The whole block was given the same
amount of plant food as the other groves, but differed in that
its phosphoric acid was carried in the form of two sources-
acid phosphate and steamed bone. The constitution of this fer-
tilizer was practically the same as that of the fertilizer which
was used on all of the groves prior to the time the experiment
was started.
Except in the fifth grove, the plots consisted of three rows
extending entirely across the grove, and were separated by a
row of buffer trees. A buffer tree is one whose halves receive
the same fertilizer treatment as the trees in the adjacent plots.
The purpose of this arrangement was to compare the plot
treatments on trees growing under practically the same soil
conditions, and to have them in replicate. By this plan, each of
the phosphoric acid treatments were repeated four times, and
each of these treatments were given two applications of ground
limestone.
Wherever possible, the plots extended in the same direction
as the slopes.
With the exception of the raw phosphates, all fertilizer
sources were factory mixed. The raw phosphates were applied
separately at about the same time that the mixed fertilizers
were applied. Only one application of ground limestone has
been made in the groves. This was given in July 1917 at the
rate of two tons to each acre.
MONTAGE GROVE
The source of phosphoric acid used in the fertilizer for the
trees in the Montague grove was soft phosphate, except in the fer-
tilizer for three plots in the middle of the grove. In one plot,
pebble phosphate was substituted for soft phosphate; in another,
acid phosphate was substituted, and in the third, steamed bone.
A fourth plot was included, to which ground limestone was
applied in addition to the fertilizer. (See Fig. 5.)


48R






Annual Report, 1918


WEST HALF OF THE MORRELL LOT
This block of trees is given a fertilizer in which steamed bone
is the source of phosphoric acid. There are three plots which
receive acid phosphate, soft phosphate and pebble phosphate
instead of the steamed bone, and one plot that receives ground
limestone in addition to the steamed bone fertilizer.

WEST HALF OF THE HOME GROVE
The trees in this portion of the grove receive a fertilizer in
which acid phosphate is the source of phosphoric acid. There
are three plots that receive pebble phosphate, steamed bone and
soft phosphate respectively instead of the acid phosphate; and
one plot that receives ground limestone in addition to the acid
phosphate.
NEW CLEARING GROVE
This grove is given a fertilizer in which pebble phosphate is
supplied as the source of phosphoric acid. There are three
plots that receive steamed bone, acid phosphate and soft phos-
phate respectively instead of the pebble phosphate; and one plot
that is given ground limestone in addition to the pebble phos-
phate fertilizer.
EAST LOT
This whole grove is given ground limestone. It is divided
into four large plots. The sources of phosphoric acid used in
the fertilizers for the different plots are soft phosphate, acid
phosphate, pebble phosphate and steamed bone.

EAST HALVES OF MORRELL LOT AND HOME GROVE
The east halves of the Morrell Lot and the Home Grove are
not plotted. They receive a fertilizer in which one half of the
available phosphoric acid is carried as acid phosphate and the
remainder as steamed bone. It is assumed that one half of the
total phosphoric acid in the steamed bone is available. This
makes a formula that is practically the same as that of the fer-
tilizer that was used on all of the groves prior to the time that
the experiment was started.

CULTIVATION AND COVER CROP
The groves in the experiment are given practically no culti-
vation. The cutaway harrow is used to work some applications
of the fertilizer into the soil. The cover crop consists of a
volunteer growth of crab grass and beggarweed.


49R





Florida Agricultural Experiment Station


PRUNING AND SPRAYING
Following the freeze of 1917, the trees were pruned back
severely, and the dead wood removed. Some withertip developed
on scattered branches, killing the limbs back, but the amount was
negligible thruout the grove as a whole. Spraying has been done
whenever necessary for the control of whiteflies and purple
scale.
RESULTS
This experiment is not yet of sufficient duration to expect
any marked differences to develop from the various fertilizer
treatments. On a whole, the trees have made a very satisfactory
growth, but it will require a number of years for them to attain
their former size and productiveness.
During the spring of 1918, the 2-unit and larger sized trees
bloomed rather heavily and set a considerable amount of fruit.
INFLUENCE OF FERTILIZE TREATMENT ON THE COLORATION OP GRAPEFRUIT
This experiment was started in the grove of the Del Oro Fruit
Co., near Clearwater, in 1914, to determine the influence of
fertilizer treatment upon the coloration of grapefruit. Instead
of the normal deep yellow, the fruit in this grove showed a
greenish tint at maturity. This reduced its market value very
materially. The cause seemed to be correlated with one of two
factors. One was the ammonia supply in the soil; the other,
the influence of the stock upon the scion.
During many years previous to the time the experiment was
started the trees had been given regular applications of a fer-
tilizer containing 8% to 10% available phosphoric acid, some-
what more than half of which was carried in the form of finely
ground steamed bone. It was thought that. possibly the am-
monia in this organic source becoming slowly available thru
the year stimulated the trees to maintain a degree of growth
during the winter season that was detrimental to the proper
coloration of the fruit. The vegetative growth made by the
trees indicated that this might be true. The experiment was
outlined upon this basis. The plan of the experiment -and the
details of the plot treatment are published in the annual report
of this station for 1917 (Fla. Agr. Exp. Sta. Ann. Rep., 1917,
pp. 46R to 50R).
During this fiscal year, it has been found necessary to close
the experiment. The results indicate that the fertilizer treat-
ment was not a controlling factor in the development of the





Annual Report, 1918


trouble, but that the controlling factor was associated in some
way with the influence of the stock upon the scion. The dif-
ference in the percentage of green tinted fruit produced by the
trees in the plots in which steamed bone was contained as the
source of phosphoric acid in the fertilizer, and in those where
acid phosphate was substituted, was not sufficiently great to
attribute the cause to this factor. During the winters of 1914-
'15, '15-'16, and '16-'17 the trees showed only a moderate seasonal
variation in the amount of green tinted fruit. But in 1917-'18,
there was a marked reduction in all trees. This season differed
from the others in the continued low temperatures that pre-
vailed.
It has recently been learned that there is some doubt as to
the stock upon which the trees are budded. It appears that it
may be some other variety of lemon than the rough lemon.
A complete report of this experiment will be published else-
where.

INFLUENCE OP DIFFERENT RATIOS OF PHOSPHORIC ACID AND POTASH IN
FERTILIZERS UPON GROWTH AND FRUIT PRODUCTION IN CITRUS TREE
These experiments are being carried on in a large seedling
grove near Tampa and a budded grove near Sutherland, and are
a continuation of those described in the 1917 Report of this
Station. (Fla. Agr. Exp. Sta. Ann. Rep., 1917, p. 50R.) They are
being conducted to study the influence of fertilizers containing
the same sources of phosphoric acid and potash but in the fol-
lowing different ratios, upon the growth and fruit production of
grapefruit and seedling orange trees, and of three different
varieties of budded orange trees:
6% phosphoric acid................. ............. 6% potash
2% phosphoric acid.............. ................ 6% potash
12% phosphoric acid................................ 6% potash
6% phosphoric acid................................ 2% potash
6% phosphoric acid...............................12% potash
The sources used in the fertilizers are sulphate of ammonia,
nitrate of soda, dissolved bone black, steamed bone, and sulphate
of potash.
A close study of the tree growth, the character of the fruit
and the amount of fruit produced, show that no marked dif-
ferences have developed during the past year that can be at-
tributed to the fertilizer treatment. The trees have recovered
entirely from the effects of the freeze of 1917.


51R





52R Florida Agricultural Experiment Station

In the spring of 1917, an experiment to study the influence
of different ratios of phosphoric acid and potash in complete
fertilizers upon the growth of young trees, was started in a
young grove belonging to L. R. Woods of Tampa. The grove lies
adjacent to the large seedling grove near Tampa mentioned
above in which similar experiments are underway. It is one
that had been recently planted on newly cleared land and had
received no previous fertilizer treatment.
The formulas being studied in this grove are:

AMMONIA AVAILABLE PHOSPHORIC ACID POTASH
4 ... 0 ... 5%t
4 0 4
4 0.. 3
4 ..... .. .. 0 ....... 2
4 ...... .. ...... 0 . .. .. .... 1
4 0 0
4 . . 0
4 2 4
4 2 3
4 .. .. .... .... ...... 2
4 2 . ............. 1
4 2. 0
4 . . . .. .....0.... 0

4 6. .
4 ....... ......... . 4 ...... ....
4 -. .-.. --. ......4..... . ........ 2

4 ........6... ...0. .. ..... 1
4 ................................... 6 .. .......... .... ... 1
4 -.. ......................-........ . ... ............ 0
4 ...... .......... 8 ...... 1
4 .... .... 8 .. .. .. ...... 0

The trees have made a good and uniform growth thus far.
No differences are evident that can be attributed to the fertilizer
treatment.

EFFICIENCY OF FINELY GROUND PHOSPHATE ROCK, STABLE MANURE AND
LEGUMES AS A FERTILIZER FOR CITRUS TREES
This experiment is one that has been under way since 1916
in the grove of the late Dr. J. F. Corrigan at St. Leo, Fla. It
consists of thirteen plots in which phosphate rock, stable manure
and legumes are used alone and in combination, with acid phos-
phate substituted for the phosphate rock in some plots, and
mineral ammonia substituted for the legumes in others. The
trees are Tardiff and Mandarin oranges on sour stock and are
more than 15 years of age. Reference was made to this ex-
periment in the 1917 Report of this Station, p. 50R.
The trees have shown a remarkably small amount of difference
considering the radically different treatments given. It is prob-







Annual Report, 1918 53R

able that they have not yet become independent of the soil condi-
tions existing prior to the time the experiment was started. The
trees had been fertilized with a complete commercial fertilizer
until the time the experiment was started. It is therefore likely
that considerable amounts of phosphoric acid and potash were
stored in the soil and still influence the character of growth
which the trees are making.
During the spring of 1918, the trees bloomed heavily and set
a large crop of fruit.
Respectfully,
B. F. FLOYD,
Plant Physiologist.





Florida Agricultural Experiment Station


REPORT OF ASSISTANT PLANT PHYSIOLOGIST
P. H. Rolfs, Director.
Smr: I submit the following report of the Assistant Plant
Physiologist for the fiscal year ending June 30, 1918.
The main line of work for the year has been the study of the
time of development and of the structure of the fruit buds in
citrus. No one variety of citrus was used thruout this investi-
gation, Sour orange, Lue Gim Gong, and Pineapple oranges and
Walters grape-fruit being used.
A study was made of the buds in place on the trees, in order
to ascertain if there were any external differences between fruit
and leaf buds. In addition to the gross examination, a micro-
scopic examination was made. For this latter study material
from summer, fall, and spring flushes was collected at various
stages, ranging from the time the flush started growth until the
following flush was beginning visible growth.
In the gross examination no external differences were noted
that would give a clue to the kind of bud or buds that were to
develop in the cluster in the following growth. The microscopic
examination showed a cluster of two to four buds in the axil
of every leaf. At a very early stage in the development of the
flush, it was observed that all the buds were not alike. By the
latter part of November, in case of the fall flush, one or two buds
in every bud cluster examined, had become larger than the others.
In addition to this difference, in all nodes examined, there was
a distinct differentiation of the buds in the cluster; some were
fruit buds and some were leaf buds. This differentiation was
based upon differences in the crowns of the growing tips. Those
of the fruit buds were rounded with opposite projections below,
that would develop into floral parts, while below these opposite
projections there were alternate projections that would mature
into leaves. The crowns of the leaf buds were conical with only
alternate projections below, that would develop into leaves. The
development of the different buds was followed to the point where
the evident growth showed the crown differences to be distin-
guishing characters. During December and January, or up to
the time of visible growth, the buds remained dormant.
Points of importance to be considered in the future are the
frequency of the flower buds, the time when flower buds are
differentiated, the time when it is determined which bud or buds


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Annual Report, 1918 55R

are to develop, and a study of the controlling factors in the
development of the flower buds.
Respectfully,
MILDRED NOTHNAGEL,
Assistant Plant Physiologist.





Florida Agricultural Experiment Station


REPORT OF ENTOMOLOGIST

P. H. Rolfs, Director.
SIR: I submit herewith the following report of the Ento-
mologist for the fiscal year ending June 30, 1918.

THE VELVET-BEAN CATERPILLAR
(Anticarsia gemmatilis)
The studies of this insect were confined largely to the parasites
and predators.
Erica carosa has been added to the list of host plants. The
moths arrived earlier than usual in 1917. On July 20 not only
moths, but third stage larvae were found at Gainesville. The
first moths must have arrived in early July.

CONTROL OF ROOT-KNOT NEMATODES
CYANAMID
Former experiments in controlling nematodes by the applica-
tion of calcium cyanamide to the soil, before planting (Fla. Agr.
Exp. Sta. Ann. Rep. 1917, p. 53R) were continued.
At the Experiment Station this year, we were able to make use
of a tract of land irrigated by an overhead sprinkling system,
thus establishing conditions comparable to those on most truck
farms of the State. The results at the Station paralleled and
verified those of last year. While the nematodes in the treated
plots were not completely exterminated they were reduced to a
point where they did but little damage to the winter and spring
crops.
Some of the cooperative experiments at Sanford and Braden-
town resulted in disaster to the crop. Several acres were treated
and a month later set out to celery. Very serious burning re-
sulted, not only on the first crop, but to another set out three
months after treatment. This occurred on the same type of land,
treated in the same manner, by the same persons, and at the
same time of the year as similar plots treated last year when the
method was an entire success. We cannot account for this di-
versity of results unless it was due to a difference in the cyanamid
used. Evidently a ton per acre is too heavy a dose to be always
safe. No such results were noted in the plots on the Station
farm even when the material was at the rate of three tons per
acre.


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Annual Report, 1918


Conditions incident to the war have practically cut off the
supply of cyanamid and that used at Bradentown and Sanford
had been in stock for some time.

CYANIDE-AMMONIUM SULPHATE TREATMENT

This treatment was first used on a small scale by Prof. Wood-
ward of the California experiment station. In his experiments
the soil was sprinkled with a solution of cyanide at the rate of
600 pounds per acre. This was immediately followed by a solu-
tion of ammonium sulphate at the rate of 900 pounds per acre.
The ammonium sulphate hastens the disintegration and action
of the cyanide.
We had previously used cyanide without the ammonium sul-
phate with unsatisfactory results. It was spread over the land
as a powder, and then dissolved by thoro irrigation; and applied
in the form of a solution which was poured into holes about a
foot apart.
In our experiments during the past year we have used
strengths varying from 100 to 800 pounds per acre, and have
applied it in solution over the entire surface of the soil and in
the form of a powder which was at once dissolved by a thoro
irrigation. In all cases the sodium cyanide was at once followed
by the application of ammonium sulphate in solution, using 150%
of the weight of the sodium cyanide.
The results paralleled quite closely those obtained with cyana-
mid. Even 800 pounds per acre did not entirely exterminate the
nematodes, but did reduce their numbers to such an extent that
they did not again reach destructive abundance for nearly a
year. On the plots receiving 300 pounds or less per acre there
was no noticeable decrease in the number of nematodes, altho
the size of the plants afterwards grown on these plots as com-
pared with those grown on the check plots was greatly increased
by the fertilizing value of the cyanide and ammonium sulphate.
The cost of this method is considerably greater than that
of the cyanamid treatment, but it has an advantage in that there
need be no long delay between treatment and planting. Because
of this and of the comparative safety to the crop, this method will
probably be preferred for the treatment of the more valuable
seed beds such as those intended for celery or lettuce. Because
of the smaller cost, the cyanamid method will probably appeal
most strongly to growers who have a considerable acreage to


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Florida Agricultural Experiment Station


treat. But even this is so costly that it will be used only on the
most intensively cultivated truck lands.
THE SUMMER FALLOW
Some little experience with a winter fallow was recorded in
the last report (p. 58R). During the past year a summer fallow
was tried. The plot, about one seventh of an acre, was plowed
the first week in August, 1917, and kept in constant cultivation
until October. No vegetation was allowed to grow, nor was a
surface crust allowed to remain on the ground. After each
rain the surface crust was broken so as to allow free entry to
the air. In October this plot was planted to susceptible crops.
The reduction in the number of nematodes as compared with
other plots which grew a crop of velvet beans during the sum-
mer, was marked and was about equal to that obtained by the
use of 600 pounds of cyanide or a ton of cyanamid per acre.
The check plot had a good growth of velvet beans which covered
the ground well so that very few weeds were present.
The fallowing of the land has been tried by others but does not
seem to have been accompanied by such frequent and thoro
cultivation. The writer is indebted to Dr. Sherbakoff of the
Department of Plant Pathology for valuable suggestions in this
connection. Conditions for this method of control are excep-
tionally favorable during the Florida summer. The continuously
high temperature and abundant rainfall supply ideal conditions
for the hatching of eggs of nematodes, provided they are sup-
plied with plenty of oxygen. But our heavy summer rains
pack the soil and a crust soon forms which interferes with the
proper aeration of uncultivated soil as shown by the acid reaction
and general growth of Eleocharis. This lack of aeration is cor-
rected by the frequent cultivation.
The results obtained with the summer fallow suggest that more
thoro and quicker results in the reduction of the numbers of
nematodes would be obtained from the growing of resistant
plants in infested soil if the surface was frequently stirred. To
accomplish this it would be advisable to plant in rows, such
crops as cowpeas and velvet beans. Experiments are now being
conducted along this line, together with further tests of summer
fallow.
PLANT BUGS
These, especially the Southern green stink-bug or "pumpkin
bug" (Nezara viridula), were not as destructive in citrus groves
during the fall of 1917 as during that of 1916.


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Annual Report, 1918


During the winter, some notes were collected on the hiberna-
tion and food preferences of these bugs, and early in May active
studies of the life history and parasites of the pumpkin bug
were taken up. Prof. Carl J. Drake, associate professor of
entomology in the New York school of forestry at Syracuse
University, was employed during the summer for this purpose.
This work is still in progress.
The hibernation of the "pumpkin bug" is incomplete. Many
individuals truly hibernate and during the winter can be found
underneath the loose bark of dead trees and in other protected
situations. These are generally darker in color than the active
feeding bugs. Some are quite brown while more of them are
pinkish in color. Many adult bugs, however, remain all winter
on green plants, usually actively feeding altho they are quiescent
during the coldest weather. December and the first part of
January were remarkable for the continuously low temperatures,
yet large numbers of adults were always to be found on a plot
of radishes on the Station grounds.
No breeding takes place during the winter. Most of the
nymphs have become adults by the middle of November and
breeding is not resumed until late in February and not until well
along in March were nymphs numerous.
The radish is one of the preferred host plants, particularly
when seed pods are present. As long as the radish remains
green it affords complete protection to collards and tomatoes.
These bugs often cause much damage in tomato fields by at-
tacking the fruits, their punctures causing unsightly hard spots
and affording avenues of entry for organisms of decay. The
planting of a few rows of radishes, especially about the edges of
the fields would be a wise precaution in those localities where
damage has been severe.

THE IMPORTATION OF PARASITES

The experiments of the previous year with Delphastus cata-
linae (Fla. Agr. Exp. Sta. Ann. Rep. 1917, p. 59R) were so en-
couraging that several hundred beetles were imported from
California. These were liberated in several groves in different
parts of the State. In at least three of these groves the beetles
have maintained themselves thruout the winter and increased at
a satisfactory rate. The outlook for their becoming established
is decidedly encouraging.


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Florida Agricultural Experiment Station


INSECTS ATTACKING CORN
In cooperation with the Bureau of Entomology, U. S. Dept of
Agr., the quantitative study of the insect damage to corn was con-
tinued and valuable data gathered.

INSECTS OF THE YEAR
A noteworthy characteristic of the early part of the summer
was the scarcity of mosquitoes. Not for many years have they
been so scarce. This is undoubtedly due to drought. In the
Gainesville section at least, altho there were moderately heavy
showers during the spring so that crops and vegetation generally
did not suffer more than usual, there were no soaking rains to
saturate the earth to ground-water levels. As a result the small
streams and swamps were lower than for many years.
The plant-bug (Adelphocoris rapids) damaged cotton in July
by puncturing squares and young bolls, causing them to drop.
The sweet-potato caterpillars (Prodenia sp.) exacted their
usual toll of the crop. Complaints began to come in by the middle
of July. A very severe infestation on the University grounds
was completely controlled by a single application of the "Kansas
bait" applied in the evening. Only a fraction of one percent of
the caterpillars escaped.
In August the woolly whitefly (Aleurothrixus howardii) was
sent in from Wabasso. This is the first report from St. Lucie
county.
The broad-nosed weevil (Epicaerus formidulosus), which is so
frequently mistaken for the cotton-boll weevil, was especially
abundant. It attacked especially the foliage of cotton and young
tobacco. In November it was sent in from Jensen where it was
reported as injuring beans.
The slug (Vaginulus floridensis) was sent in from Dania in
October. It was stated to be doing considerable damage to to-
matoes.
In August the big yellow plant-bug (Corecoris confluentus)
was sent in from Bokelia, where it was severely injuring toma-
toes. This bug is quite common in the southern part of the
State.
The Colorado potato beetle (Leptinotarsa 10-lineata) was sent
in from Panama City. This is the first report from the Gulf


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Annual Report, 1918 61R

coast of Florida. It has been reported in many of the northern
tier of counties. It seems to be slowly working southward.
In April the corn ear-worm (Chloridea obsoleta) was sent in
from Vero in the buds of geraniums which it had mined.
During March and April the membracid or tree-hopper (Platy-
corus 4-vittata) was more common than usual. It infested oaks
mainly, especially live and wateroaks.
In June the papaw snout beetle (Derolomus basalis) was sent
in from several localities, with the statement that it was injuring
cotton squares to such an extent as to cause them to drop. This
weevil seems to be a general feeder. We have found it on velvet
beans, blossoms of chinquepin, and many other plants.
Respectfully,
J. R. WATSON,
Entomologist.





Florida Agricultural Experiment Station


REPORT OF PLANT PATHOLOGIST
P. H. Rolfs, Director.
Sm: I submit the following report of the Plant Pathologist
for the fiscal year ending June 30, 1918.
As a result of war conditions, the general program of the work
has been somewhat disturbed. Farmers of the State have made
frequent calls on our time for information relative to the identity
and control of diseases affecting the more staple crops. The loss
of our laboratory assistant during the latter part of the year,
and the scarcity of trained help in pathological lines has also been
a handicap. Nevertheless, certain progress has been made in the
different lines of investigation and some new work has been
added to our program.
Three regular bulletins, two press bulletins and one extension
circular have been prepared by the department during the year.
Various news articles have been furnished the Agricultural News
Service and other papers.
CITRUS DISEASES
The work on citrus diseases has been limited to the continua-
tion of the experiments for the control of Melanose and Gum-
mosis. These experiments have been under way for several
seasons. In regard to Melanose, the results of our investigations
for the past five years have been published in Bulletin No. 145.
AVOCADO DISEASES
This is a new problem that has been added to our project this
season. At present it includes the study of Avocado Scab and
Fruit Spotting, two diseases that may prove to be serious factors
in the production of avocado fruits and trees.
These diseases have made their appearance apparently within
the last four or five years, and the past season both of them were
so prevalent in certain localities as to warrant an immediate
investigation. A preliminary study of the two diseases was made
during the fall and winter of 1917. In cooperation with the
State Plant Board, a field survey was made of a number of
avocado plantings in Dade county, and both Avocado Scab and
Fruit Spotting were found to be more widely distributed than
was at first suspected. The work of the field survey was done
chiefly by Henry Schumacher of Homestead, Fla., one of the
canker inspectors detailed for this work.


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Annual Report, 1918


A considerable amount of laboratory work has been completed,
and the cause of Avocado Scab isolated and determined.
AVOCADO SCAB
This is a foliage disease that appears to have developed in
Florida within the past few years. The disease was reported


Fig. 6.-Scab on young foliage of avocado seedling


plant


and described by the writer in Press Bulletin 289, March 20,
1918, and later reported before the State Horticultural Society
at its annual meeting in April, 1918.
Scab is chiefly a disease of nursery seedlings and promises
to be one not easily controlled. At present it is more severe on
the seedling avocado. It attacks some of the budded varieties,


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Florida Agricultural Experiment Station


but in a milder form. The disease has also been found to a
limited extent on both the foliage and fruits of bearing seedling
avocado trees. However, at present it cannot be considered a
serious factor in the bearing grove.
The disease is of interest owing to its close relationship to
Citrus Scab, which it resembles in certain respects. It attacks
the tender foliage, causing a characteristic spotting. In severe


Fig. 7.-Well developed spots on mature seedling fruit


attacks the leaves are distorted and crinkled, somewhat similar
to the effect produced by Citrus Scab. (Fig. 6.)
The cause of Avocado Scab has been isolated on numerous
occasions and has been identified as Cladosporium citri, the same
fungus that causes scab on citrus. The pathogenicity of this
fungus for the avocado has been definitely established by inocu-
lation. Pure cultures of the fungus isolated from infected avo-
cado leaves and stems, readily infect tender healthy avocado
foliage if proper moisture conditions are maintained. Strains
of the fungus isolated from the avocado will also infect young
citrus foliage under proper growth and moisture conditions, pro-


64R






Annual Report, 1918


during in every case the typical symptoms of Citrus Scab, that
are identical with those of natural infection. Strains of C. citri
have been isolated from naturally infected citrus leaves, and
these strains have been applied to healthy avocado foliage. In
all attempts thus far no infection has resulted on the avocado
from the strains of C. citri obtained direct from Citrus Scab in-
fections. It appears that a strain of C. citri from citrus has
some time in the past adapted itself to the avocado and has
become exceedingly virulent on the seedling variety of this host.



















Fig. 8.-Decay of inner tissue of fruit, following surface spotting

The strains from citrus and avocado seem to be identical as far
as habits of growth and cultural characters are concerned. How-
ever, a more exhaustive study of the morphology of these two
strains may show some slight differences. This has not been
possible up to the present time.
AVOCADO FRUIT SPOTTING
Specimens of this disease first came to the writer's attention
in August, 1917. A preliminary study of the disease was at-
tempted at the time, but the season was too far advanced to
accomplish more than a study of specimens sent to the laboratory.
This spotting is a troublesome disease and frequently causes
heavy losses of fruit. Thus far, it is found mainly on seedling
fruits. However, a few cases have been observed on the Trapp.


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Florida Agricultural Experiment Station


The disease seems to appear about the time the fruit is approach-
ing maturity and the fully developed spots are quite evident on
the ripened fruit. A rapid decay may follow the spotting, es-
pecially in the matured fruits.
This disease has been occasionally observed by avocado grow-
ers for the past four or five years, and has been considered the
result of various causes. The past season it was unusually preva-
lent, and in some cases as high as 90% of the fruit on a tree
has been found af-
fected. Such fruits
are usually worth-
less for shipping,
since they are not
only unsightly but
may decay rapidly
when packed and
shipped. The effect
on the fruit is quite
characteristic. The
injury occurs in the
form of definite
spots scattered over
the surface of the
affected fruit. (Fig.
7.) The spots are
round, brown to
dark brown or black
in color, and vary
Fig. 9.-Fruit badly affected with spotting from an eighth to
three fourths of an inch in diameter. They are composed of
hard, dry, corky tissue, which penetrates the skin of the fruit
and into the meat. The surfaces of the spots are slightly sunken,
often cracked or fissured, and in some cases a zonated effect is
observed. When once formed the spots do not appear to increase
in size on the surface of the skin, but a decay of meat below may
follow, especially in the ripened fruit. (Fig. 8.) Affected fruits
may show a few to many spots of various sizes, and frequently
spots grow together, forming irregular patches, the surface of
which are deeply cracked or broken. (Fig. 9.) Severe attacks on
less mature fruits may cause them to become misshapen or
undersized.


66R







Annual Report, 1918 67R

A spotting very similar to that on the fruits has been observed
in the green bark of twigs, and a typical leaf spotting is fre-
quently associated with the disease.
The cause of the disease has not yet been determined, altho
it appears to be of fungus origin. Several fungi have been
isolated from the spots on fruits, two of which appear more or
less constantly associated with the disease. It will remain for
a series of inoculation experiments to determine what relation
these fungi bear to the disease. These experiments are planned
for the coming season when growing fruits will be available for
inoculation.
H. E. STEVENS,
Plant Pathologist.





Florida Agricultural Experiment Station


REPORT OF ASSOCIATE PLANT PATHOLOGIST
P. H. Rolfs, Director.
SIR: I submit the following report of the Associate Plant
Pathologist for the fiscal year ending June 30, 1918.

DISEASES OF TRUCK CROPS
In accordance with the progress of the work along certain
lines and with the growing need of study of certain other prob-
lems, the working
project has this
year been some-
what modified.
The work on the
cause of damping
off was discontin-
ued because it
was definitely de-
termined by the
writer's studies
of preceding
years .
Some further
studies were
made on Phomop-
sis of eggplant
and on solanace-
Fig. 10.-Pure growth of the fungus Phomopsis
vexans produced from each of the small bits of Ous blight. Late
diseased tissues taken from "canker" spots on in the year, work
eggplant stem and planted into the plate.
on varietal sus-
ceptibility of beans to rust and root-knot was also started. Other-
wise the work has been continued along the same lines as during
the preceding year.
PHOMOPSIS OF EGGPLANT
The fungus Phomopsis vexans (Sacc. & Syd.) Harter (see
fig. 10) is, so far, the most serious parasite of eggplant in the
State. It causes fruit rot, stem canker, leaf spot, damping off
(1) By these studies it was determined that the most common cause of
damping off in the State is Rhizoctonia solani Kuhn.; it was also found that
some other fungi, Pythium debaryanum Hesse, certain species of Fusarium,
Sclerotinia libertiana Fuckel and Phomopsis vezans (Sacc. & Syd.) Harter,
are sometimes responsible for the disease. (Fla. Agr. Exp. Sta. Ann. Rep.
1916, p. 81R, and 1917, p. 76R.)


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Annual Report, 1918


and tipover of the plant. This fungus causes a very serious loss
to the growers each year, and therefore, while considerable in-
formation in regard to it has already been availablet" some
further study has been needed.
The work was started by a series of eggplant seed tests to
determine their contamination with the fungus. According to
all of the writer's previous field observations on this disease, and
according to the results of his test of a batch of eggplant seed
obtained from a local market and found to be badly contaminated,
it was very reasonable to suspect that the fungus is introduced
into the seed bed and hence into the field, by means of the seed.
In the writer's experience with testing various seed for
the presence of certain parasitic fungi, he finds that almost
invariably the seed also carry on the surface some rapidly grow-
ing saprophytic fungi, such as Mucors, and bacteria. If not
checked in some way these fungi and bacteria would, as a rule,
overrun the plates and obscure development of the parasites.
A slight surface disinfection of the seed before testing seemed
to be of advantage. It is plain, of course, that such a treatment
might also affect some of the parasites. Some preliminary trials
of seed disinfection with one percent solution of copper sulphate,
for five minutes, showed that such disinfection practically en-
tirely frees the surface of the seed from various bacteria, and
at least partly from saprophytic fungi. This treatment does
not noticeably reduce the parasites. Therefore, this year when
testing eggplant for the presence of Phomopsis vexans, the fol-
lowing method was employed:
The seed were soaked for five minutes in one percent solution
of copper sulphate, rinsed in sterile water, and planted in petri
dishes into which was previously poured about 10 c. c. of corn-
meal agar. In each test 50 seeds were planted. In all twenty-
four samples of eggplant seed were tested in this way. The
samples included all of the leading commercial and home garden
varieties of eggplant and were obtained from seven leading seed
houses, fairly representing our main source of supply.
Two of the tested samples, one of which was an important com-
mercial variety, showed to be badly contaminated with Phomop-
sis. This finding, when considered with the result of a previous

(1) See Harter, L. L. Fruit rot, leaf spot, and stem blight of eggplant
caused by Phomopsis vexans. Jour. Agr. Res. 2: 331-338, 5 pl., 1914, and
Sherbakoff, C. D., in Fla. Agr. Exp. Sta. Ann. Repts. 1915, xcvii; 1916, 92R;
and 1917, 77R and 78R.


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Florida Agricultural Experiment Station


eggplant-seed test, shows undoubtedly that introduction of the
'Phomopsis into the seed bed and field takes place by means of
the seed contaminated with the fungus.
The fungus is evidently not a native of Florida, which fact
gives us a suggestion for prevention of the trouble. This should
consist in the use of seed positively known to be free from the
fungus. Such seed can be obtained by selecting healthy fruit
and extracting the seed under necessary sanitary precautions.


Fig. 11.-Tomato plants in different stages of attack by bacterial blight.
Note especially the largest and least affected plant on the right, where
the wilt is just beginning to show up on the top leaves. The plants were
artificially inoculated with the bacteria.

The fact that out of twenty-four samples of eggplant seed
tested by the writer twenty-two were free from the fungus,
shows that the seed dealers surely could produce fungus-free
seed. This should indeed be demanded from them, with some
reasonable guarantee of such seed.
The matter of control of the disease in fields and farms where
it is already introduced, requires some further work. This
consists mainly of finding where the infection takes place most
readily, and the length of time some other crop should be planted
on the soil to free it of the fungus.


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Annual Report, 1918


SOLANACEOUS BLIGHT (Brown Rot)
This disease caused by Bacterium solanacearum E. F. Sm. is
of special importance in the State because of its frequent and
severe attacks on some of the truck crops most extensively grown
here, such as tomatoes (fig. 11) and Irish potatoes (fig. 12).
This season several important Irish potato districts in Florida


Fig. 12.-Irish potato plants in different stages of attack by bacterial
blight. The plants were artificially inoculated

were badly hit by the disease. In some of the potato fields 75
percent of the plants, and even more, were killed.
The disease has been known for some time and considerable
reliable information in regard to the cause, occurrence of and
plants affected, has been accumulated. Some important sug-
gestions in regard to its control have also been made'1.

(1) See Smith, Erwin F., Bacteria in its relation to plant diseases, III:
174-219, figs. 81-114, pls. 23-32. August, 1914.


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Florida Agricultural Experiment Station


However, there are many phases of the disease that are not
known at present. Some of these are of extreme importance to
the growers and therefore must be thoroly studied until deter-
mined. Among these are the following: varietal susceptibility
of the tomato and other plants subject to the disease; effect of
soil type and treatment on the disease; what cultivated and wild
plants of Florida are immune to it; and the length of time re-
quired to free a field once affected with the blight so that sus-
ceptible crops can be safely planted on the land.
The work on the disease consisted mainly in some preliminary
tests of tomato varietal susceptibility. One hundred and eighty
samples of tomato seeds were secured from different seed dealers
and every sample was tested. Many of these samples were dupli-
cates of the same varieties, especially of the most popular ones,
and thus only about 60 different varieties were represented.
In the early part of last February about 100 seeds of each
of these samples were planted in flats in the greenhouse. These
flats were filled with soil taken from a field in which the tomato
crop of the preceding season was almost completely destroyed by
the blight. About 50 seeds of each were also planted on green-
house benches, using soil presumably free from the blight. At
this stage of the work, soil sterilization was not considered
necessary. A few weeks later young plants of each variety of
tomatoes from both flats and the benches were transplanted into
small clay or paper pots. At the beginning of April the plants
from the flats with contaminated soil were planted in a field
which for a number of years had not been used for any of the
plants known to be subject to blight, and which had grown velvet
beans for the past several years. This field experiment was to
determine just how readily tomato plants in the seedling stage
become attacked by the disease from infected soil, and if one
variety is more susceptible than another in this respect. The
records show that blight appeared in comparatively few in-
stances among the plants, and was scattered among nearly all
of the varieties. Therefore, no conclusion could be reached
showing any one variety more susceptible than another to in-
fection from the soil during an early stage of the plant life.
The tomato plants originally planted on the benches were
used for blight inoculation work. At least three plants of each
variety were used for these inoculations, which was done when
the plants were from three to four weeks old. They were inocu-
lated by pricking the stems with a coarse, slightly blunt-pointed


72R






Annual Report, 1918


needle. Before each prick was made, the needle was thrust into
a living Irish potato stem considerably affected with the blight
bacteria. The Irish potato stems of a dozen pot-grown potato
plants were prepared beforehand by inoculation with pure cul-
tures of the bacteria. The latter were isolated from a blighted
potato plant found early in the season in a field near Hastings.
From one to all three inoculated plants of each of the tried
tomato varieties showed definite symptoms of the disease in
from four days to two weeks' time. The disease showed up in
brown rot of the stems near the inoculation point and often at a
considerable distance from it; in the formation of more or less
pronounced incipient roots on affected parts of the stems; in the
flabby and shriveled condition of the latter; and in the wilting of
the green tips and leaves. In certain instances one or the other
of the symptoms was absent; in many cases tho the disease
progressed so rapidly as to kill the whole plant in one to three
weeks' time after the inoculations were made. The records show
that the cases of successful inoculations bore no relation to the
variety of the plant, but were rather in relation to the growth
condition of each individual plant. The plants with soft watery
stems seemed to succumb to the bacteria most readily. Almost
without exception the inoculated plant showed some definite
symptom or symptoms of the spread of the bacteria within the
plant for some distance from the point of inoculation. Never-
theless many of the plants which had at the time somewhat hard
and woody stems withstood the disease for a long time, and a
number of them continued to grow and even bear fruit. This,
again, without any definite indication that any one of the varie-
ties was more susceptible than the others.
Therefore, the only definite conclusion that can be made from
these inoculation experiments is that of all varieties tried no
one seems to be resistant to the disease. The indiscriminate
appearance of the disease in the plants planted in bacteria in-
fested soil and the comparative failure of the inoculations into
the plants with somewhat hardened stems, are the facts that do
not quite correspond to the commonly observed behavior of the
disease in the field. They are in contradiction especially with the
well known fact that under ordinary field conditions the blight
usually does not show until about the time the plants begin to
fruit; from then on the disease usually spreads rapidly, killing
the plants. Some environmental factors evidently play a great
part in the development of the disease, and to the study of these


73R





Florida Agricultural Experiment Station


factors the close attention of the writer will be largely directed
in his future work.
BUCKEYE ROT OF TOMATO FRUIT
This new disease of tomato was reported for the first time by
the writer in the 1916 Annual Report (pp. 88R-89R). Results of
some further studies of it were published in a technical paper,
Phytopathology, 7:119-129, figs. 5, 1917, and in the 1917 Annual
Report (pp. 78R-79R). The accumulated information in regard
to this disease was then incorporated in Station Bulletins No.
139 and No. 146.
Field observations and study of the fungus Phytophthora ter-
restria causing the disease, led to the belief, first that the fungus
lives in the soil and that the disease gets into the fruit from
such infested soil; and second, that the fungus of buckeye rot
of tomato must be of much wider occurrence than it heretofore
had actually been observed. (The disease up to last year was
recorded by the writer as occurring on the lower end of the
Florida East Coast and in Manatee county.) Both of these ex-
pectations were fully substantiated by the work and reports of
this year.
This year a successful isolation of the fungus from the soil
was made and thus the soil habitat of it established. The soil
sample from which the fungus was isolated was received from
a field near Palmetto. During the season just past the tomato
crop on this field was seriously affected with the buckeye. The
soil sample when brought into the laboratory was placed in a
disinfected moist chamber and thoroly moistened with sterile
water. Four nearly full grown but yet green tomato fruits,
taken from a field which in all probability was free from the
disease, were then placed on top of the soil. Before placing the
fruits in the moist chamber the calyxes were removed and the
fruit disinfected with 1:1000 corrosive sublimate for fifteen
minutes. Three days later three of the fruits, and on the
fourth day the remaining one, showed plain symptoms of buck-
eye rot. On the fifth day small bits of the diseased tissues from
each of the fruits were planted into petri dishes with cornmeal
agar, each of the plantings yielding pure growth of buckeye rot
fungus, Ph. terrestria. The bits of the diseased tissues were
taken after the fruit surface was disinfected and the epidermis
removed.


74R





/
Annual Report, 1918 75R

In regard to the expected wide occurrence of the disease, or
of the fungus causing it, my studies of certain fungi showed
that a fungus identical with Ph. terrestrial occurs in California,
Cuba and Argentine"' on citrus, and in Jamaica(2) on cocoanut
trees. According to a recent report of Dr. Jagger, considerable
buckeye rot of tomato fruit was found in the market gardening
district around New Orleans, La., where the growers state that
the disease had been with them for a number of years. In a
recent issue of Revista de Agricultura, Comercio y Trabajo,
Habana, Cuba (Vol. I, pp. 301-303, 1918), S. C. Bruner records
the disease as being frequent in that country. Finally, re-
examination of certain literature from India (Dastur, J. F., in
Mem. Dept. Agr. India, Bot. ser. Vol. V, No. 4), shows that
probably the same fungus described there as Ph. parasitica Das-
tur, is causing an important disease of young castor bean plants
in that country.
Thus the information available at the present time shows that
the fungus and the disease are indeed of wide occurrence, cov-
ering in this country the states of Florida, Louisiana, and Cali-
fornia, and the following foreign countries: Cuba, Argentine,
Jamaica, and probably India.
DAMPING OFF
Certain experiments on control of damping off were carried
out, but as no additional information was obtained from them,
they will not be reported. It should be mentioned here, how-
ever, that the treatment of the seed bed soil with a half percent
solution of copper sulphate did not show any hindering effect
on the growth of the plants. The soil was treated in the same
way and at the same time and rate as in certain cooperative ex-
periments of last year; celery plants were used in this experi-
ment, the same as last year. Nevertheless the results of last
year's experiments as previously reported (Fla. Agr. Exp. Sta.
Ann. Rep. 1917, p. 77R) showed reduction of "celery germination
and the rate of plant growth". The difference can be ascribed to
various factors, the temperature and moisture conditions prob-
ably being the most important. Whatever may be the reason of
this difference, it is plain that much more work will be needed
before we will be sure of the efficiency of this method of treat-
(1) Cultures of these three fungi were received from Prof. H. S. Fawcett.
42) The culture from the cocoanut tree was received from Prof. S. F.
Ashby.





Florida Agricultural Experiment Station


ment and of the proper details of its application for control of
the disease.
TRUCK DISEASE SURVEY
To ascertain the relative importance of various diseases of
truck crops in the State, it seemed desirable to conduct a survey
of the diseases in certain limited areas in which culture of certain
important truck crops is concentrated. The funds available for
this work were rather limited and permitted only a part-time
employment of a local grower. Nevertheless the information
obtained is of considerable value in estimating the relative im-
portance of common truck diseases in the districts surveyed.
The work was done during last spring in the neighborhoods of
Pahokee, Ft. Myers and Palmetto, and dealt chiefly with diseases
of tomatoes, Irish potatoes and peppers. The survey shows
plainly the great importance in these districts of early blight
of the first two crops, and of Cercospora leaf spot of pepper.

TRUCK DISEASES OF SPECIAL IMPORTANCE
During the year nearly all common diseases of truck crops in
the State were at work, at least at their usual rate of destruction.
Some of them, tho, caused a great deal more damage than usual.
Of these the following deserve special mention.
LATE BLIGHT AND EARLY BLIGHT OF THE IRISH POTATO caused
considerable damage to the crop in some districts. The former
disease was conspicuous in the northeastern counties of the
State, while the latter was quite severe further south. This
was especially true in Lee county, where potato plants in many of
the fields were, due to the disease, dead far ahead of the normal
time, and thus did not give a yield that otherwise should be
expected.
BACTERIAL BLIGHT OF THE IRISH POTATO was this year of un-
usual severity. Clay. St. Johns, Volusia, and other neighboring
counties, were suffering from the disease more than ordinarily.
In these counties the damage caused by it alone was greater than
the combined damage of all other diseases of the crop. Accord-
ing to Dr. L. R. Hesler, fields with 75% of the plants affected
were not infrequently found and it would be a safe estimate
that the damage to the crop was not less than five percent of the
total yield.
NAILHEAD RUST OF TOMATO (early blight) caused considerable
damage to the crop this year, especially on the lower East Coast.


76R






Annual Report, 1918


In this section the average damage to the fruit in the field alone
amounted to not less than about 20 percent of the total yield.
Instances were observed where the loss amounted to 80 percent
of the crop. Some of the leading growers of certain communities
were so discouraged by the disease as to become quite skeptical
about the future of tomato culture in that district. The hope is


Fig. 13.-Alternaria fruit-spot on eggplant


entertained, tho, that these growers will finally decide that it
will be best to continue to grow this very important crop, keep-
ing in mind that the acreage of each grower should be small
enough so that he can take the best care of the crop. This care
must include the proper and thoro spraying against nailhead
rust.
BLACKHEART OF CELERY caused greater than usual damage.
Dr. L. R. Hesler, of the U. S. Dept. of Agr., estimates the loss


77R






78R Florida Agricultural Experiment Station

in the Sanford district at about 20% of the total number of the
mature plants. This estimate is based on actual counts.
PHOMOPSIS FRUIT ROT OF EGGPLANT was observed to destroy
practically every fruit in some fields.
ALTERNARIA FRUIT SPOT OF EGGPLANT (see fig. 13) was ob-
served in sections of Central and Southwest Florida.
CERCOSPORA LEAF SPOT OF PEPPER was especially severe in
places this year.
Respectfully,
C. D. SHERBAKOFF,
Associate Plant Pathologist.






Annual Report, 1918


REPORT OF CHEMIST

P. H. Rolfs, Director.
SIR: I submit the following report of the Chemist for the
fiscal year ending June 30, 1918.

CITRUS EXPERIMENT GROVE

Measurement of Trees.-In table No. 26 is shown the increase
in diameter of the trees of the various plots from 1909 to 1918.
The trees were measured six inches above the bud, and the
figures for each plot represent the average of the ten trees in that
plot. Referring to this table it will be noted that plot 1 stands
at the head, making the largest amount of growth of any of the
plots. In 1917 plot 2 made the largest amount of growth.
However, the difference between them is very small. Plot 2
appeared to have more fruit set than plot 1. The clean culture
plots still continue near the head of the list.
The plot receiving no fertilizer, number 43, has dropped still
lower in the list, ranking number 42.
A study of the fertilizer treatment of the best twenty-four
plots brings out the fact that fifteen of these received sulphate
of ammonia as the only source of nitrogen; all the other sources
of nitrogen being represented in the fertilizer used on the re-
maining nine plots. Twenty out of the twenty four best plots
received acid phosphate as the sole source of phosphoric acid;
the other four received steamed bone, floats (4 times standard)
with cottonseed meal, floats (4 times standard), and dissolved
bone-black, respectively.
In the case of sources of potash, the high-grade sulphate was
used on twenty two of the twenty four best plots, the remaining
two plots receiving the low-grade sulphate and hardwood ashes.
A study of the twenty four poorer -plots leads one to the con-
clusion that no particular source of nitrogen can be singled out
as having been injurious to growth or as having induced a
relatively small amount of growth. That too much nitrogen is
injurious to growth is, however, brought out very conclusively.
A comparison of plot 5 with plots 6 and 7 illustrates this point.
Plot 5 received one and one half times the standard amount of
nitrogen and phosphoric acid and stands number 47 in the list.
Plot 7 receiving one and one half times the standard amount of


79R





Florida Agricultural Experiment Station


TABLE 26

GAIN IN:
PLOT 32NDS OF FEBTIUZER TREATMENT
I AN INCH I
1 137 One half standard.
2 135 Standard.
47 132 Nitrogen from dried blood, clean culture
46 131 Standard, clean culture.
12 129 Standard and air-slaked lime.
13 128 Standard, mulched.
48 124 Nitrogen from nitrate of soda, clean culture.
25 124 Phosphoric acid from steamed bone.
31 122 Standard.
16 122 Half nitrogen, nitrate of soda, half sulphate of ammonia.
37 121 Potash from low-grade sulphate.
36 120 Phosphoric acid from floats (4 times the amount). Cotton-
seed meal.
8 120 Phosphoric acid and potash decreased by one half.
35 119 Phosphoric acid from floats (4 times the amount).
41 119 Standard.
22 119 Half nitrogen cottonseed meal, half sulphate of ammonia.
30 119 Acid phosphate, nitrate of soda, hardwood ashes.
6 118 Phosphoric acid and potash, increased by one half.
9 117 Phosphoric acid and nitrogen decreased by one half.
45 116 Standard, mulched.
44 116 Standard.
20 115 Nitrogen from cottonseed meal.
24 112 Phosphoric acid from dissolved bone-black.
23 112 Half nitrogen cottonseed meal, half nitrate of soda.
32 I 112 Phosphoric acid from dissolved bone-black.
38 110 Potash from muriate.
26 110 Phosphoric acid from steamed bone (2 times amount).
21 109 Nitrogen from cottonseed meal, ground limestone.
29 108 7% percent potash in June, 7% in October, 3 in February.
42 108 Potash from nitrate of potash; balance of nitrogen nitrate
of soda.
3 107 Twice standard.
19 106 Half nitrogen from nitrate of soda, half from dried blood.
7 106 Nitrogen and potash increased by one half.
15 103 Nitrogen from nitrate of soda.
11 103 Standard and ground limestone.
18 103 Half nitrogen sulphate of ammonia, half dried blood.
14 102 Standard.
10 102 Nitrogen and potash decreased by one half.
34 102 Phosphoric acid from floats (2 times amount).
27 101 Phosphoric acid from Thomas slag. Nitrate of soda.
33 101 Phosphoric acid from floats.
43 100 No fertilizer.
40 98 Potash from kainit.
28 97 Phosphoric acid from Thomas slag (2 times amount),
nitrate of soda.
17 84 Nitrogen from dried blood.
39 80 Standard and ground limestone.
5 71 Phosphoric acid and nitrogen increased by one half.
4 59 Four times standard.


80R





82R


LEAVES STEMS
Plot i N CaO MgO Fe jP205i N CaO MgOI Fe lP205


I 2.31
2.30
2.45
2.25
2.38
2.45
2.35
2.39
2.44
2.20
2.44
2.32
2.40
2.44
2.42
2.46
2.31
2.20
2.41
2.31
2.59
2.26
2.36
2.20
2.45
2.33
2.51
2.74
2.49
2.51
2.20
2.36
2.50
2.44
2.34
2.46
2.53
2.56
2.23
2.46
2.43
2.32
2.43
2.26
2.50
2.43
2.54
2.63


6.26
5.90
5.35
4.25
4.49
4.66
3.72
6.23
5.44
4.56
6.45
5.94
4.33
4.42
4.38
5.27
4.96
4.42
4.72
4.01
6.28
4.62
4.49
5.46
5.27
5.10
4.07
4.83
4.60
5.39
4.82
4.80
4.24
4.80
4.27
4.37
4.38
4.82
6.22
4.60
5.10
4.37
4.45
3.97
4.14
4.36
4.33
4.66


.89
.90
-.73
.55
.75
.83
.69
.93
.93
.79
.69
.72
.93
.86
.83
.82
.75
.78
.79
.85
.68
.88
.93
.82
.90
.92
.91
.76
.80
.86
.88
.78
.78
.92
.84
.99
1.06
.91
.62
.81
.90
.84
1.29
.96
1.00
.76
.73
.76


.022
.018
.024
.023
.016
.019
.012
.018
.024
.029
.027
.021
.019
.023
.024
.024
.018
.017
.018
.020
.022
.019
.032
.016
.019
.021
.032
.030
.022
.025
.024
.023
.024
.025
.026
.016
.020
.026
.026
.025
.023
.026
.019
.021
.028
.027
.025
.025


.54
.50
.47
.49
.44
.48
.44
.44
.55
.49
.46
.51
.47
.42
.51
.52
.49
.45
.42
.45
.43
.42
.46
.41
.46
.57
.48
.50
.42
.48
.49
.41
.43
.44
.45
.49
.47
.46
.51
.49
.45
.52
.49
.50
.51
.44
.46
.50


1.27
1.24
1.23
1.44
1.34
1.41
1.42
1.30
1.29
1.30
1.49
1.26
1.41
1.31
1.38
1.28
1.11
125
1.37
1.41
1.64
1.18
1.25
1.20
1.33
1.26
1.53
1.62
1.47
1.61
1.27
1.33
1.30
1.52
1.47
1.41
1.55
1.34
1.37
1.25
1.11
1.23
1.27
1.32
1.58
1.63
1.44
1.50


4.04
3.81
3.48
3.07
3.15
3.20
2.82
4.23
3.51
S3.30
4.44
4.26
2.69
3.04
3.02
3.74
3.40
3.10
3.15
2.56
4.23
2.78
2.80
3.98
3.33
3.26
2.68
3.01
3.05
3.34
3.32
3.30
2.71
2.70
2.88
2.81
2.39
4.32
2.61
3.17
3.36
3.11
2.65
2.91
2.87
2.73
3.08
3.02


.53
.53
.55
.44
.38
.45
.48
.51
.66
.57
.59
.48
.46
.54
.56
.57
.62
.50
.52
.50
.49
.38
.56
.60
.61
.57
.61
.43
.51
.49
.60
.56
.50
.53
.59
.71
.63
.38
.59
.52
.59
.54
.93
.65
.70
.45
.45
.46


.028
.035
.034
.098
.042
.053
.030
.039
.048
.039
.030
.045
.022
.024
.026
.029
.018
.032
.014
.016
.017
.017
.031
.018
.020
.022
.018
.021
.021
.020
.023
.023
.024
.022
.022
.022
.019
.033
.081
.031
.023
.028
.027
.020
.024
.025
.022
.027
.033


Florida Agricultural Experiment Station

TABLE 27


Plot 43, receiving no fertilizer, shows no striking differences
from the other plots except that both leaves and stems contain
more magnesia than any of the other plots.


.42
.39
.87
.39
.31
.38
.34
.38
.39
.37
.40
.39
.40
34
.40
.40
.34
.31
.33
.36
.36
.32
.35
.30
.33
.39
.40
.40
.33
.41
.38
.33
.35
.36
.34
.40
.40
.41
.37
.41
.37
.43
.89
.43
.42
.38
.41
.41




Annual Report, 1918


nitrogen and potash ranks number 38. Where the phosphor,
acid and potash have been thus increased the growth has been
much better as shown by plot number 6, which ranks 18 in the
list. Plot 4, which received four times the standard amount of
all three elements, made the poorest growth of any of the plots
and developed serious injury, due undoubtedly, in large measure
to the excessive amount of nitrogen.
An injurious effect on growth was also produced by the use
of ground-4limestone, already noted in previous reports. The
plots receiving this material now rank 28, 35 and 46 in the list.
The limestone has been discontinued but the trees still show the
small, frenched leaves and have the ragged, unthrifty appearance
which seems to be characteristic of limestone injury.
Poor growth has been made where kainit and Thomas slag
were used on the trees. The plot receiving kainit ranked 43 in
the list and the slag plots 40 and 44 respectively.
CHEMICAL COMPOSITION OF LEAVES AND STEMS
In table No. 27 is given a partial analysis of leaves and stems
collected from the different plots. These samples were taken
in the fall of 1915 and represent one year's growth. Few striking
differences are noted in a study of these analyses. The stems run
lower than the leaves in every element except the iron, which
averages very slightly higher in the stems.
Comparing analyses of leaves from the different plots it is
noted that the figures for nitrogen, magnesia, iron and phos-
phoric acid run very close together thruout the table. The lime
content of plots 11, 12, 21, 30 and 39 which receive lime in one
form or another average over 6 percent, which is considerably
higher than the average for the remainder of the plots. This
higher lime content is not found in the stems.
It is interesting to note that in the case of plots 4, 5, 6 and 7,
which all receive excessive amounts of nitrogen, the stems con-
tain considerably less of this element than those from the re-
mainder of the plots.





Annual Report, 1918 83R

COLLECTION OF SOIL SAMPLES
In the spring soil samples were taken from the different plots
and from between the rows for determinations of nitrogen,
phosphoric acid and potash. The phosphoric acid analyses have
nearly all been made.

MISCELLANEOUS WORK
A few miscellaneous analyses have been made during the
year. A feed analysis made on palmetto berries is given below:
Moisture .............................10.98 percent
Ash .................................. 3.99 percent
Protein ................................................. 6.84 percent
Ether extract ..................................... 4.64 percent
Crude fiber ..........................................10.14 percent
Respectfully,
S. E. COLLISION,
Chemist.




Florida Agricultural Experiment Station


REPORT OF ASSISTANT AGRONOMIST

P. H. Rolfs, Director.
Sm: I submit the following report of the Assistant Agrono-
mist for the fiscal year ending June 30, 1918.
Two experiments were conducted during the year, one a
variety test of cotton, and the other on hill selection of sweet
potatoes.
COTTON VARIETY TEST
After securing from several experiment stations and reliable
breeders recommendations of the most likely varieties of cotton
for Florida under boll weevil conditions, a selection was made
of ten of what seemed to be the most promising varieties. They
were Cleveland Big Boll, Mexican Big Boll, Hartsville No. 9,
Hartsville No. 11, Cook's Improved, Webber's No. 49, Trice, Lone
Star, Durange, and Sosnowski. The last named belongs to the
Sea Island group, while all the others are of the Upland group.
The plots were 3/50 of an acre in size and each variety was
run in triplicate. The following table gives the average yields
in pounds of seed cotton, for first, second, and third picking,
1917, also the percentage of total yield first picking:
TABLE 28





Mexican Big Boll- ........... 225 132 42 400 56
Hartsville No. 9.............. 242 257 79 478 42
Hartsville No. 11 ............ 127 292 81 500 25
Cook's Improved ....... 350 323 3 726 48
Webber's No. 49.......... 277 220 35 532 43
Trice ...................... 443 135 37 615 72
Lone Star ........................ 350 263 78 691 51
Durange ...... ........ 375 240 60 675 56
Sosnowski ................... 117 138 81 336 35

Besides these ten varieties some 16 varieties were planted in
single rows, the seed being furnished by G. L. Meloy of the
Bureau of Plant Industry. Only one variety, the Acala, showed
up as favorable with the others, yielding a total of 600 pounds
per acre.
This test is being continued with the ten varieties used in
1917, and four duplicates are being used instead of three.


84R






Annual Report, 1918


SWEET POTATO EXPERIMENTS
During the fall of 1916, 129 hills of sweet potatoes were care-
fully dug and weighed just as they came from the field. Each
hill was kept separate by storing in paper bags. In the spring
of 1917 the potatoes were again weighed, counted and notes taken
on sizes and general appearance. All of them kept perfectly,
they were bedded in the same order as they came from the field
and plantings were made on April 5, 27, and June 25, the last
planting being made from cuttings. At each planting ten plants
were used from each hill.
The plantings were made in rows approximately 3 feet and 8
inches apart, and plants set 2 feet in the drill, making about 6000
plants per acre.
In the final tabulations there were only 124 parent hills to
be compared. Dividing them on a basis of their original 1916
weight, the lighter 62 hills averaged .84 pounds per hill; while
the 62 heavier hills averaged 2.20 pounds per hill. The respective
yields of the 1917, 10 plant averages were: first planting 1.14
pounds and 1.36 pounds; second planting 1.00 pounds, and 1.09
pounds, or an average for the two plantings in favor of the
heavier parent hills of .15 pounds per plant or about 15 bushels
per acre.
If as many as five divisions were made there was a break in
the curve and the fourth division yielded less than the third.
With the last planting the yield averaged only .4 pounds per
plant and there was no correlation between yield of parent hill
and the offspring plantings.
Other correlations in number of potatoes per hill showed no
relationship.
PEANUTS

An experiment has been started with peanuts to test the value
of various phosphates, limestone, hydrated lime, and dried blood
on the yield of nuts and hay. All treatments are being run
in triplicate.
Respectfully,
J. E. TURLINGTON,
Assistant Agronomist.


85R





Florida Agricultural Experiment Station


REPORT OF THE FORAGE CROP SPECIALIST
P. H. Rolfs, Director.
Sra: I submit the following report of the Forage Crop Spe-
cialist for the fiscal year ending June 30, 1918.
The investigational work of the department has been directed
along two well defined lines. One of these covers the experi-
mental work conducted on the trial grounds of the station at
Gainesville, while the other has to do with field tests made in
cooperation with growers in widely distributed localities thruout
the State.
FIELD WORK ON THE EXPERIMENT STATION FARM
The work performed on the Experiment Station grounds at
Gainesville has included field tests of approximately 150 dif-
ferent varieties. Many of these were of comparatively recent
introduction, and little information was available to indicate
how closely local conditions might coincide with their require-
ments. While the work has been in progress for a number of
years, during the past two years its scope has been considerably
enlarged and the area of land devoted to it has been extended
by about two and a half acres. As a result of the work a number
of species have stood out more or less prominently and some
valuable data has been collected.

SOME PROMISING NEW GRASSES
NAPIEB GRAss (Pennisetum purpureum)
This is a rank growing cane-like grass from Tropical Africa
and is among those species that show promise of special merit.
It was first introduced into this country in 1913, by the U. S.
Dept. of Agr., and in the spring of 1915 the initial planting was
made at the Experiment Station at Gainesville. It is a vigorous
growing non-saccharine perennial, reaching a height of from 6 to
12 feet or more, depending upon the fertility of the soil and the
general conditions under which it is grown. This grass furnishes
a palatable and nutritious green feed; and under favorable con-
ditions it should yield three or more cuttings during the course
of a growing season. It is readily propagated from "seed canes"
taken from well ripened stems in a manner very similar to the
usual method of growing Japanese cane or any of the other
varieties of sugar cane. The plants tiller extensively, and where
this method seems desirable as a means of increasing the acreage


86R






Annual Report, 1918


the large root clump may be divided into a number of plants.
This tendency to tiller (fig. 14) or to produce many shoots in-
sures, even from a very limited beginning, the rapid increase of
material for seed-cane propagation.
In their rapidity of reproduction Napier grass and Merker
grass seem to be practically identical. The test begun with im-
ported Merker grass seed and discussed below under the subject
"Merker grass" may, therefore, be considered as an indication
of the results that might
be expected from Napier
grass.
A plot of Napier grass
grown on the Experiment
Station grounds in the sea-
son of 1917 bore a few scat-
tering seed spikes during the
first half of November of
that year. Germination tests
to determine the viability of
this locally grown seed have
not yet been made. This
grass would seem to be well
adapted for use either as a
soiling crop or for silage;
tho sufficient material to al-
low of systematic feeding
tests with it has not yet be-
come available. Fig. 14.-Napier grass, grown from
come divisions of the root bunch
MERKER GRAss (Pennisetum merkeri)
Merker grass is a species very similar to Napier grass, and
closely related to it botanically. It was first introduced into
this country in 1916 from South Africa by the U. S. Dept. of
Agr. In the spring of 1917 the Experiment Station obtained
from that department, material with which to plant a small test
plot. Imported seed of this species was obtained in the spring
of 1918 and sown in a green house "seed flat" on March 5, 1918.
The plants resulting from this seeding were transplanted to
the field on April 3, at which time they were about 5 inches high.
On July 15, or three months and 13 days after transplanting,
these plants (see fig. 15) measured from 6 to 8 feet in height.


87R





Florida Agricultural Experiment Station


There were 178 plants bearing a total of 3164 canes, or an ave-
rage of 17.7 canes per hill. At the same time there were also a
large number of suckers less than 3 feet high, all of which were
disregarded in making this count. Merker grass closely resembles
Napier grass in general appearances and in habits of growth; but
the latter seems to produce
a little the coarser canes,
and is probably a little
\ more leafy where the two
are grown under similar
conditions. The methods
mentioned above in connec-
tion with the propagation
of Napier grass may also
be employed in growing
this species. The seed-
heads of this grass, tho
borne as early as the first
week in May, in contradis-
tinction to the late seeding
habits of Napier grass, are
1 o n g, yellow, millet-like
spikes, closely resembling
those of the latter species
in general appearance. Like
Napier grass, it would seem
to be best adapted for use
Fig. 15.-Merker grass, grown from as a soiling crop or as si-
seed lage.

CARIB GRASS (Eriochloa subglabra)
This grass was obtained from Brazil in 1914 by the U. S. Dept.
of Agr., and during the past two or three years it has been grown
to a limited extent in Florida. It is best suited to conditions
existing in the south half of the State, and plantings have been
made chiefly within that section.
This species grows from long, coarse, surface runners and
so closely resembles the more common Para grass, Panicum bar-
binode, as to sometimes render the two grasses almost indis-
tinguishable. Carib grass is, however, somewhat more leafy
during its early stages of growth, is of more erect habits, and
seeds more freely than does Para grass. In the latitude of


88R






Annual Report, 1918


Gainesville, the seeding period of Carib grass begins several
weeks in advance of that of Para grass. During the season of
1917 these two species were grown in adjacent plots. Para
grass, No. 1460, was uninjured by the severe winter weather,
while at least 95 percent of the Carib grass was winter killed.
A small quantity of this Carib grass was taken up and planted
on the farm of Chas. E. Lucius of Summerfield, Fla., on Decem-
ber 4, 1917, before the cold weather had injured it. This plant-
ing, altho less than 60 miles south of Gainesville, withstood the
rigors of winter without injury. The crop may be utilized as
pasture, for soiling purposes, or for hay. In its preference for
a low, wet soil, it shows a further resemblance to Para grass.
Carib grass thrives best under the warm climatic conditions of
the south half of the State, and at Gainesville it has made com-
paratively slow progress during the cool weather of early spring.
This last statement also applies to Para grass, with which Carib
grass will usually be compared.

MANILA GRASS (Osterdamia matrella)
This is a low growing, dense, perennial that is best suited for
pasture purposes. It makes a short thick growth somewhat like
that of Bermuda grass, but differs materially from that variety in
its habit of spreading almost entirely from underground stems,
and in its less extensive system of surface runners. Owing to these
differences, it makes less rapid growth than does Bermuda grass.
In the fall of 1917, growth here at Gainesville was killed by the
first severe frost which occurred on the morning of November 25.
During the past spring, Manila grass was a little later than
Bermuda grass in starting into growth.

BLUE COUCH GRASS (Digitaria didactyla)
Blue Couch resembles Bermuda grass in general appearance.
It is a sod grass, producing an abundance of short, fine, erect
growth. It is best adapted for pasturage. This grass has a
distinct glaucous coloring which lends it the blue appearance
suggested in its common name. On the comparatively light soils
of the trial plots at the Experiment Station Blue Couch grass has
not shown any distinct superiority over Bermuda grass. It has,
however, shown indications of the aggressiveness and persistence
that are essential characteristics of a good pasture grass; and
it is possible that it may prove of real value within its limi-
tations, once its special demands have been made clear. It


89R





Florida Agricultural Expetiment Station


seems to be fully as susceptible to injury from frost as is Ber-
muda grass.
KIKUYU GRAss (Pennisetum longistylum)
This is a creeping grass, resembling St. Augustine grass to
some extent, but being softer in texture and superior in feeding
value to that species. It is provided with thick fleshy stems that
lie on or near the surface of the ground. Judging from obser-
vations covering a single winter's season, it will not top-kill by
cold as quickly as does Bermuda grass, but as the roots lie near
the surface of the ground and are less well protected, it appears
to actually winter kill at a temperature that causes no injury
to Bermuda grass. There was, however, but little injury done at
Gainesville by the unusually severe weather of the past winter.
Kikuyu grass is a native of East Africa and was introduced
into this country by the U. S. Dept. of Agr. While it has shown
considerable promise at the Experiment Station, it has been sub-
ject to a sort of leaf-spot disease that seriously affects its growth.
This disease manifests itself by the appearance of circular brown
spots on the leaf blades and, in later progress, by the presence
of masses of dry dead leaves among the low undergrowth. A
disease showing similar effects upon Bermuda grass and Giant
Bermuda grass was noted during the past year.
PASPALUM NOTATUM
A member of the water grass genus, Paspalum notatum, also
shows considerable promise as a pasture grass. It spreads by
means of thick rooting stems that grow near the ground surface,
insuring, in time, a good sod even where thin planting has been
practiced. It may be readily propagated from the seed or by
planting small pieces of sod. This grass has produced light
yields of seed during a more or less continuous period from June
until frost. As compared with the common water grass, Pas-
palum dilatatum, it is more quickly susceptible to injury from
low temperatures, the top growth being killed by the first severe
frost, while that of Paspalum dilatatum will withstand, consider-
able freezing. In our test plots of this grass, many of the creep-
ing roots died and this condition was first noted during the fall
of 1917. This adverse state prevailed thruout the past season,
with little or no improvement. This injury was thought to
result from the severe weather occurring during the spring of
1917 tho this theory has not been fully established. The plots
suffered little or no permanent injury from cold during the


90R






Annual Report, 1918


91R


past winter. Where cattle have had access to it, this grass has
been grazed with relish and no loss from dying out such as
was noted in connection with our ungrazed plots, has been ob-






-^ ALACHUA !PC,. ,

..LEVY I 0c1 --




PASCO HUAo- 0
'M 1N !- "


MANATfE' '




SDE SOTO
LMAP B , EACo








a mrq l or oos orv it i r
LEE h ...
SiBROWARD




--4




Fig. 16.-The dots indicate locations of cooperative grass plots

served. The chief advantage of this grass over the more com-
mon water grass, Paspalum dilatatum, is its tendency to spread
and more quickly form a good sod. Moreover, it is provided
with a remarkably thick and tangling root system, which would





Florida Agricultural Experiment Station


indicate an ability to withstand trampling under heavy grazing
conditions.
OTHER PROMISING SPECIES
Among other miscellaneous grasses that have given some
measure of promise, Chrysopogon montanus, a comparatively
fine growing perennial species, has made heavy growth on light
soil and has come on quickly in early spring. It promises well as
a permanent hay crop; but its success here will hinge very
largely upon whether or not good stands can be obtained from
sowings of the locally produced seed. During the past season
it seeded profusely in our trial plots. An annual grass, Bra-
chiaria plantaginea, has, at least from the standpoint of yield,
made a satisfactory showing. It seeds very freely here, but
the seed appear to scatter badly upon approaching maturity,
thus suggesting some difficulty in obtaining seed in quantity
for general farm plantings. Seeds collected in the fall of 1917
showed a high percent of germination when planted the following
spring. This grass shows a tendency to reseed the ground and
produce volunteer crops in succeeding seasons, once it has be-
come established and allowed to seed.
Toda grass, Andropogon faveolatus, a perennial grass obtained
during the past year from the Office of Forage Crop Investiga-
tions of the U. S. Dept. of Agr., has made good growth. This
species is said to be especially fitted for use as a hay crop and
it is not claimed to be entirely satisfactory for pasture pur-
poses. As it has been under test for only a single season, its
habits and tendencies under local conditions are not sufficiently
well known to justify any undue hopes in its final success.
In addition to those mentioned above, numerous minor species
have also shown some degree of promise.

COOPERATIVE PLANTINGS
The State of Florida represents a wide range of conditions
with reference to soil type, temperature, and moisture. Where
information is based entirely upon the results of field tests per-
formed at a single point, these variable conditions render the
interpretation of experimental data complex and often contra-
dictory. In testing comparatively unknown species, these facts
were especially obvious; and it seemed evident that our station
work could be profitably supplemented by field work conducted
upon the farms of and in cooperation with growers who are


92R






Annual Report, 1918 93R

personally interested in the work. Moreover, if the best
results were to be expected, it was manifestly essential that
such tests should be made to cover the entire state and to deal
with as wide a range of conditions as possible. Acting upon
this general line of reasoning, work of this nature has been
started in cooperation with some 25 different planters in locali-
ties well dispersed thruout the state. With each of these co-
operators some ten or a dozen of our most promising new grasses
have been planted on a small scale. The chief object is to pro-
vide a means for the study of these grasses under as wide a
range of conditions as is possible. With a view of indicating the
geographical distribution of these plantings, the outline map of
Florida, fig. 16, has been prepared. In this map the position
of each dot indicates the approximate location of a coopera-
tive plot. As a result of this work it is hoped that important
data bearing upon the limitations and requirements of these lit-
tle known grasses may be obtained. To insure maximum results
from this work, however, would necessitate the systematic in-
spection of these plots at comparatively short intervals, a course
that would involve much time and the expenditure of more funds
than are now available for the purpose.
Respectfully,
J. B. THOMPSON,
Forage Crop Specialist.


REPORT OF FORAGE CROP EXPERIMENT FUND
Period Ending June 30, 1918
Appropriation ................................ ............ ...... ........................... $2500.00
EXPENDITURES:*
Salary .----..--... ............. .......... ................. ....... $ 1050.00
Labor ...................................... .. 125.40
Seeds, Plants and Sundry Supplies ............................ 76.19
Postage and Stationery .............................................................. 1.20
Traveling Expenses ...................................... ................. 264.87
Freight and Express .......................... ............ 97.47
Furniture and Fixtures ........................................ 40.00
$ 1655.13
Balance July 1, 1918..................... .............. ... $ 844.87
L. R. HUNTER,
Assistant to the Auditor.

*These items of expense are included in the Auditor's report.









INDEX
TO ANNUAL REPORT, BULLETINS, AND PRESS BULLETINS


Acanthocephala femorata, 235
Acid phosphate, as fertilizer for po-
tatoes, 35R
Acrobasis Hebeseella, 152
nubella, 150
Adelphocoris rapidus, 60R
Agronomy, 12R
Aleurocanthus woglumi, 185
Aleurodes nubifera, 178
Aleurothrizus floccosus, 184
howardii, 181, 60R
Allies of the citrus grower, 259
Analysis of silage, 278 PB
Animal Industry, 8R
Anthracnose, pecan, 137
Anticarsia gemmatilis, 56R
Ants, 251
control, 252
Aphis gossypii, 254
Aphis, melon, 254
control, 257
Armored scales, 187
Assistant Agronomist, report of,
84R
Assistant Plant Physiologist, report
of, 54R
Associate Plant Pathologist, 68R
Associations, cow testing, 75
Auditor, report of, 15R
Australian lady-beetle, 218
Avocado diseases, 62R
fruit spotting, 65R
scab, 63R
Avocado scab, 289 PB, 63R

Back, E. A., 181
Bacterial blight, tomato, 120
Bacterium solanacearum, 71R
Bagworms, 238
Barnacle scale, 211
Bay whitefly, 184
Bemesia inconspicua, 184
Berger, E. W., 178
Big-thighed plant-bug, 235
Bird grasshopper, 248
Birds, 260
Blackfly, spiny, 185
Black fungus, 193
Black scale, 209
Black spot, tomato, 126
Blood-red lady-beetle, 194
Blue Couch grass, 89R
Board of Control, 6R
Boll weevil in Sea Island cotton,
286 PB
Borers, pin-head, 241
shot-hole, 241
trunk and limbs, 241


Botryodphaeria berengeriana, 141
Broad-winged katydid, 249
Brown leaf spot, pecan, 145
Brown rot, 71R
tomato, 129
Buckeye rot, tomato, 127, 74R
Bulletins, press, 14R
summary, 13R

California red scale, 203
California yellow scale, 203
Cane, Japanese, 89
Carib grass, 88R
Caterpillar, sweet potato, 280 PB
Celery, blackheart, 77R
Cephalothecium sp., 144
Ceratitis capitata, 239
Cercospora fusca, 145
Cercospora leaf spot, pepper, 76R,
78R
Ceroplastes, 209
C. Ceriferus, 211
C. cirrippediformis, 211
C. floridensis, 209
Chaff scale, 204
Chalcids, 197
Changes in Station staff, 12R
Chemist, report of, 79R
Chemistry, 11R
Chionaspis citri, 206
Chloridea obsoleta, 61R
Chrysobothris femorata, 157
Chrysopogon montanus, 92R
Chrysomphalus aonidum, 200
C. aurantii, 203
C. Citrinus, 203
C. dictyospermum, 203
Citrus, development of fruit buds,
54R
structure of fruit buds, 54R
Citrus diseases, 10R, 62R
dieback, 3
foot rot, 279 PB
melanose, 101
Citrus fertilizer experiments, 39R,
79R
Chrysopa, 194
Citrus mealy-bug, 214
Citrus root-weevil, 240
Cladosporium citri, 64R, 289 PB
Cloudy-winged whitefly, 178
control, 180
Coccidae, 186
Coccinae, 186, 206
Coccus hesperidum, 207
Coleophora caryaefoliella, 154
Collison, S. E., report of Chemist,
79R





Indes


Common citrus whitefly, 172
control, 175
Control of Citrus foot rot, 279 PB
Control of sweet potato caterpillar,
280 -PB
Controlling poultry lice, 287 PB
Convergent lady-beetle, 194
Corecoria confluentis, 60R
Corn, fertilizer experiment, 25R
Corn silage, analysis of, 278 PB
Cossula magnifica, 160
Cotton boll weevil, 286 PB
Cotton stainer, 235
Cotton, variety test, 84R
Cottony cushion scale, 216
Cow testing associations, 75
Cryptophyllus concavus, 249
Cucumber-beetle, striped, 258
Cylas formicarius, 284 PB
Cycloneda munda, 258

Dactylopinae, 186, 213
Dairy herd, Station, 16R
changes in, 16R
record of, 17R
register of merit, 17R
Dairying, 57
Dairy pointers, 75
Dairy rations, balanced, 67
Dairy, record sheet, 61
Damping off, 75R
Datana integerrima, 155
Delphastus catalinae, 174, 59R
Derolomus basalis, 61R
D. pusillus, 174
Diabrotica vittata, 258
Dialeorodes citri, 172
D. citrifolii, 178
Diaspinae, 186
Dictyophorus reticulatus, 248
Dictyospermum scale, 203
Dieback, 3
causal factors, 3, 12, 18
control, 19
curative methods, 26
development, 10
distribution, 4
of pecan, 141
preventive methods, 19
primary symptoms, 5
secondary symptoms, 10
trees susceptible, 4
Digitaria didactyla, 89R
Director, report of, 7R
Diseases of Citrus, 62R
Diseases and insect pests of pecan,
133
Diseases of the tomato, 117
Downy darkling beetle, 194
Dozier, H. L., 169
Dysdercus suturellus, 235


Early Blight, tomato, 125
Eggplant seed, contamination of
with Phomopais, 69R
Eggplant, Phomopsis fruit rot, 78R
alternaria fruit spot, 78R
Elaphidion insre, 241
Entomogenous fungi, 192
black fungus, 193
gray-headed scale-fungus, 193
red-headed scale-fungus, 192
Entomologist, report of, 58R
Entomological studies, 10R
Epicaerus formidulosus, 60R
Epitragus tomentosus, 194
Eretmocerus haldemani, 182, 183
Erica carosa, 56R
Erichlan subglabra, 88R
Eriophes oleivorus, 220
Euchistus variolaris, 235
Euthrynchus floridensis, 232
Experiment Station, dairy herd, 16R
dairy herd record, 17R
publications, 13R
staff, 6R
staff changes, 12R
Experiments
beef cattle feeding, 18R, 20R
citrus fertilizer, 39R, 79R
control of gummosis, 62R
control of melanose, 62R
control of root-knot nematodes,
56R
corn fertilizer, 23R
cotton, 84R
dairy cattle feeding, 77
eggplant seed, contamination of,
with phomopsis, 69R
forage crops, 86R
hog feeding, 21R, 22R, 44, 53
Japanese cane fertilizer, 23R
peanuts, 85R
potato fertilizer, 28R
sweet potato, 85R
sweet potato fertilizer, 23R
tomato bacterial blight, 72R

Fall webworm, pecan, 155
Feeding for milk production, 77
Fertilizers, for Japanese cane, 89
Fertilizer experiments, 28R
with potatoes, 28R
with citrus trees, 39R
Field experiments with fertilizers,
28R
Flat-headed apple-tree borer, 157
Flies, parasitic, 261
Flocculent whitefly, 184
Florida flower thrips, 226
spraying for, 230
Florida red scale, 200
control, 202
Florida wax scale, 209






Index


Floyd, B. F., dieback or exanthema
of citrus trees, 1
report of Plant Physiologist, 27R
Formulas-
Kansas bait, 280 PB
lime-sulphur, 285 PB
Frankliniella bispiosus projects,
226
Fruit fly, Mediterranean, 239
Morelas, 240
Fruit spotting, avocado, 63R
Fungi, beneficial, 285 PB
Fusarial wilt, tomato, 123
Fusicladium efusum, 135
Glomerella cingulata, 137
Gnomonia sp., 146
Golden-eyed lace-wing, 195
Graham, K. H., report of auditor,
15R
Grasses, cooperative plantings, 92R
Grasses, Blue Couch, 89R
Carib, 88R
Kikuyu, 90R
Manila, 89R
Merker, 87R
Napier, 86R
Paspalum Notatum, 91R
Toda, 92R
Chrysopogon montanus, 92R
Grasshoppers, 237, 247
bird, 248
lubberly locust, 248
yellow-lined, 248
Gray-headed scale-fungus, 193
Green soldier bug, 231
Guava whitefly, 184
Gummosis, 62R
Hag moth, 247
Hemerobius, 196, 258
Hemispherical scale, 208
Hickory twig-girdler, pecan, 159
Hippodamia convergens, 258
Hogs, 20R
care of herd, 38
choosing a breed, 36
fattening feeds for, 281 PB
feeding experiments, 44, 54
improving quality, 281 PB
peanut meal feeding test, 291 PB
principles of feeding, 39
Hog raising in Florida, 281 PB
Hymenorus obscurus, 243
Hyphantria cunea, 155
Icerya purchase, 216
Inconspicuous whitefly, 184
Influence of fertilizer on coloration
of grapefruit, 50R
Injurious insects, 169
Insect pests and diseases of pecan,
133
Insects, troublesome, 60R


Irish potato diseases-
bacterial blight, 71R, 76R
early blight, 76R
late blight, 76R
Japanese cane, fertilizer experiment,
24R, 25R
Japanese cane, fertilizers, 89
Japanese wax scale, 211
Jassid, orange, 250
Katydids, 237, 249
broad-winged, 249
angular-winged, 250
Kernel spot, pecan, 144
Kikuyu grass, 90R
Lace-winged flies, 194, 257
Lady-beetles
Australian, 218
blood-red, 194
convergent, 194
twice-stabbed, 174, 193
Laetilia coccidivora, 211, 215
Large plant-bugs, 231
Laspeyresia caryana, 153
Leaf blotch, pecan, 146
Leaf case-borer, pecan, 150
Leaf-footed plant-bugs, 235
Leaf mould, tomato, 126
Legumes, as fertilizer, 52R
Lepidosophes, 187
Leptinotarsa 10-lineata, 60R
L. gloverii, 199
Leptoglossus phyllopus, 235
Locust, lubberly, 248
Loftin, U. C., 169
Long scale, 199
Long-tailed mealy-bug, 216
Lubberly locust, 248
Manila grass, 89R
Mason, A. C., 169
Matz, J., diseases and insect pests
of the pecan, 133
Mealy-bug, citrus, 214
long-tailed, 216
Mealy-bugs, 213
Mealy shield scale, 212
Mediterranean fruit fly, 239
Megalopyge opercularis, 245
Melanose, 62R
Melanose II, 101
appearance, 104
cause, 107
control, 113
Melon aphis, 254
Merker grass, 87R
Mexican wax scale, 211
Microcentrum retinerve, 250
Microsphaera alni, 138
Mildew, pecan, 138
Milk, feeding for milk production,
77






Index


Milk, cost of production, 60
Miner, tineid, 241
Minor pests-of fruit, 236
Minor pests of trees, 243
Morelas fruit fly, 240
Moth, hag, 247
puss, 245
Mulberry whitefly, 185
Nail-head scale, 200
Napier grass, 86R
Natural enemies of caterpillars,
280 PB
Nezara hilaris, 235
N. Viridula, 231, 58R
Nitidulidae, 240
Nothnagel, Mildred, report of
Assistant Plant Physiologist,
55R
Novius cardimUs, 218
Nursery blight, pecan, 146
Oncideres cinglatus, 159
Oneometopia wndata, 250
Onion thrips, 290 PB
control of, 290 PB
Ophionectra coccicola, 193
Orange dog, 243
control, 245
Orange Jassid, 250
Orange sawyer, 241
Orange tortricids, 236
Osterdamia matrella, 89R
Pachnaeus opalus, 240
Papilio cresphontes, 243
Paraleurodes perseae, 184
Parasites-
importation of, 59R
of common citrus whitefly, 174
of Florida wax scale, 211
of plant-bugs, 232
of purple scale, 196
of wooly whitefly, 182
Parasitic flies, 261
Parlatoria pergandii, 204
Paspalum dilatatum, 90R
Paspalum notatum, 90R
Peanut meal feed, 22R, 291 PB
Pebble phosphate, 35R, 45R, 47R
Pecan bud-moth, 157
Pecan cigar case-bearer, 154
Pecan, diseases and insect pests, 133
Pecan diseases--
anthracnose, 137
brown leaf spot, 145
dieback, 141
kernel spot, 144
leaf blotch, 146
mildew, 138
nursery blight, 146
pecan rosette, 139
pink mold, 144
scab, 135


Pecan, injurious insects, 150
cigar case-bearer, 154
fall web-worm, 155
flat-headed apple-tree borer, 157
hickory phylloxera, 161
hickory twig-girdler, 159
leaf case-bearer, 150
oak or hickory cossid, 160
pecan bud-moth, 157
shuckworm, 153
walnut caterpillar, 155
Pennisetum longistylum, 90R
P. Merkeri, 87R
P. purpureum, 96R
Pepper, Cercospora leaf spot, 76R,
7811
Phomopsis citri, 107
Phomopsis vexans, of eggplant, 68R,
69R
Phoradendron flavescene, 149
Phosphate rock, as fertilizer for cit-
rus, 52R
Phosphoric acid, as fertilizer for cit-
rus, 51R
Phyllosticta caryae, 146
Phylloera caryaecaulis, 161
Phytophthora blight, tomato, 123
P. parasitica, 75R
P. terrestria, 74R, 279 PB
Pin-head borers, 241
Pink mold, pecan, 144
Plant bugs, 58R, 235
large, 231
Plant nutrition, 9R
Plant pathological studies, 10R
Plant Pathologist, report of, 62R
Plant Physiologist, report of, 27R
Platycorus 4-vittata, 61R
Pomace flies, 240
Pork production in Fla., 33
Potash, as fertilizer for citrus, 51R
Potato fertilizer experiment, 28R
Poultry lice, remedies for control,
287 PB
Predaceous bugs, 261
Predaceous insects-
on cottony cushion scale, 218
on mealy-bugs, 215
on purple scale, 193
Predaceous mites, 196
Press bulletins, 14R
Prickly-ash beetle, 254
Principles of feeding pork, 39
Proteopteryx bolliana, 157
Pseudococcus citri, 214
P. longispinus, 216
Psocids, 242
Psocus citricola, 243
P. venosus, 242
Publications, 13R
bulletins, summary, 13R
press bulletins, 14R






Index


Publications concerning citrus in-
sects, 263
Pulvinaria psidii, 212
P. pyriformis, 212
Pumpkin bug, 213
control, 232
prevention, 234
Pumpkin bugs in citrus groves,
283 PB
Purple mite, 226
Purple scale, 187
control, 197
Puss moth, 245
Pyriform scale, 212
Pythium debaryanum, 68R
Quaintance, A. L., 181
Raw phosphate, 35R, 42R, 48R
Red-headed scale-fungus, 192, 202,
203
Red spiders, 225
Rhizoctonia solani, 68R, 129
Rodents, 238
Rolfs, P. H., 202, 203
report of Director, 7R
Root-knot, tomato, 130
Root-weevil, citrus, 240
sweet-potato, 284 PB
Rosette, pecan, 139
Round scale, 200
Rufous scale, 203
Rust mite, 220
control, 222
Saddle-back, 246
Saissetia hemispheric, 208
San Jose scale, 285 PB
Sap beetles, 240
Sawyer, orange, 241
Scab, avocado, 63R, 289 PB
pecan, 135
Scale, armored, 185
barnacle, 211
black, 209
California red, 203
chaff, 204
cottony cushion, 216
dictyospermum, 203
Florida red, 200
Florida wax, 209
hemispherical, 208
Japanese, 211
long, 199
mealy-bugs, 213
mealy shield, 212
Mexican wax, 211
purple, 187
pyriform, 212
Rufous, 203
San Jose, 204
snow, 206


soft brown, 207
turtle-back, 207
unarmored or soft, 206
wax, 209
West Indian, 203
Scale-fungus, gray-headed, 193
red-headed, 192
Scavengers, bark and leaf, 242
fruit, 240
Schistocera aleutacea, 248
Sclerotinia libertiana, 68R
Sclerotial blight, tomato, 122
Scott, J. M., comparison of corn si-
lage and sweet potato silage for
milk production, 275 PB
dairying in Florida, 57
feeding for milk production, 77
fertilizers for Japanese cane, 89
peanut meal for hog feeding,
291 PB
pork production in Florida, 33
report of Animal Industrialist,
16R
Scymnus terminatus, 258
Selenaspidus articulatus, 203
Septorial blight, tomato, 121
Sharp-shooter, 250
Sherbakoff, C. D., tomato diseases,
117
report of Associate Plant Patholo-
gist, 68R
Shot-hole borer, 241, 160
Shuckworm, pecan, 153
Sibene stimylea, 246
Silage, 70, 278 PB
analysis of sweet potato silage,
278 PB
analysis of corn silage, 278 PB
Silo, advantages of, 70
Six-spotted mite, 226
Slug caterpillar, 245
Snow scale, 206
Soft brown scale, 207
Soft phosphate, 35R, 45R, 47R
Soft rot, tomato, 129
Soft scales, 206
Solanaceous blight, 71R
S. oleae, 209
Sphaerostilbe coccophila, 192
Spencer, A. P., hog raising in Flor-
ida, 281 PB
Spiny blackfly, 185
S. serialis, 248
Stable manure, 52R
Staff, Experiment Station, 6R
changes in, 12R
Stevens, H. E., citrus foot rot,
279 PB
avocado scab, 289 PB
Melanose II, 101
report of Plant Pathologist, 62R
Striped cucumber-beetle, 258






Index


Sulphur, to control rust mite, 223
Survey of truck diseases, 76R
Sweet potato, fertilizer experiment,
24R
hill selection, 85R
silage, 278 PB
Sweet potato insects-
caterpillar, 280 PB
root-weevils, 284 PB
whitefly, 184
Swine, worms, 54
Syrphus flies, 257
Tachinid fly, 261
Termes flavipes, 253
Termites, 258
as scavengers, 240
Tetraleurodes mori, 185
Tetranychus, 225
T. citri, 226
Thompson, J. B., report of Forage
Crop Specialist, 86R
Thrips, Florida flower, 226
onion, 290 PB
Thrips marks, 228
Tineid miner, 241
Tobacco, extract, 290 PB
Toda grass, 92R
Tomato bacterial blight, 72R
Tomato diseases, 117
bacterial blight, 120, 71R
black spot, 126
brown rot, 129
buckeye rot, 127, 74R
early blight, 125, 76R
fusarial wilt, 123
leaf mould, 126
nailhead rust, 76R
phytopthora blight, 123
root-knot, 130
sclerotial blight, 122
septorial blight, 121
soft rot, 129
Tortricids, orange, 236
Truck crop diseases, 68R
alternaria fruit rot of eggplant,
78R
bacterial blight of Irish potatoes,
76R
blackheart of celery, 77R
buckeye rot of tomato fruit, 71R
cercospora leaf spot of pepper,
78R
damping off, 68R
early blight of Irish potatoes, 76R
late blight of Irish potatoes, 76R
nailhead rust, 76R


phomopals fruit rot of eggplant,
78R
solanaceous blight, 71R
Trash bug, 196
Trees that harbor insects, 262
Trialeurode floridensis, 184
Triohopoda pemnipes, 261
Trirhabda breioollis, 254
T. sezmaculatus; 226
Turlington, J. E., report of Assist-
ant Agronomist, 84R
Turtle-back scale, 207
Twice-stabbed lady-beetle, 174, 193,
258
Unarmored scales, 206
Vagiswus florideneis, 60R
Vedalia, 218
Velvet bean feed, 22R
Vertebrates, 261
Walnut caterpillar, pecan, 155
Wasps, 261
Watson, J. R., bol weevil in Sea
Island cotton, 286 PB
controlling poultry lice, 287
onion thrips, 290 PB
pumpkin bugs in citrus groves,
288 PB
report of Entomologist, 58R
San Jose scale, 285 PB
sweet-potato caterpillars, 280 PB
sweet-potato root-weevils, 284 PB
Wax scales, 209
Weevil, boll, 286 PB
West Indian red scale, 208
Wheel-bug, 261
White ants; 253
Whiteflies, 170
Whitefly, bay, 184
cloudy winged, 178
common citrus, 172
flocculent, 184
guava, 184
inconspicuous, 184
mulberry, 185
sweet-potato, 184
wooly, 181
Wood lice, 253
Wooly whitefly, 181
control, 188
Xylobiops basilaris, 160
Yellow-lined grasshopper, 248
Others, W. W., 175, 191




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