Front Cover
 Table of Contents
 Letter of transmittal
 Board of control and station...

Group Title: Florida Agricultural Experiment station, report for the fiscal year ending June 30th.
Title: Report for the fiscal year ending June 30th
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00005173/00022
 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: 1923
Copyright Date: 1905
Frequency: annual
Subject: Agriculture -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
Statement of Responsibility: Florida Agricultural Experiment Station.
Dates or Sequential Designation: 1905-1930.
 Record Information
Bibliographic ID: UF00005173
Volume ID: VID00022
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
    Front Cover
        Page 1
        Page 2
    Table of Contents
        Page 3
        Page 4
    Letter of transmittal
        Page 5
    Board of control and station staff
        Page 6
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        Index 1
        Index 2
        Index 3
        Index 4
        Index 5
        Index 6
        Index 7
Full Text





ENDING JUNE 30, 1923

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Fig. .-Building of the Tobacco Experiment Station at Quincy.
Fig. '1.--Building of the Tobacco Experiment Station at Quincy.

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LETTER OF TRANSMITTAL TO GOVERNOR OF FLORIDA.................................. 5R
BOARD OF CONTROL AND STATION STAFF................................ .............. 6R
REPORT OF DIRECTOR............. ...................................-............. 7R
Introduction, 7R; Comparative Resources, 7R; Animal Industry
'and Dairying, 8R; Grass and Forage Crop Investigations, 8R;
Chemistry, 10R; Plant Pathology, 11R; Entomology, 12R; Hor-
ticulture, 13R; Library, 14R; Editor, 14R; Citrus Experiment
Station, 14R; Tobacco Experiment Station, 15R; Everglades
Experiment Station, 16R; Changes in Staff, 17R; Publications,
17R; Bulletins and Summary of Bulletins, 17R; Press Bulletins,
REPORT OF AUDITOR............. ............... ...... .. ..................... 20R
REPORT OF ANIMAL INDUSTRIALIST..................................... 21R
Soft Pork Studies, 21R; Pig Feeding Experiment, 25R; Experi-
ment with Dairy Herd, 26R; Live Stock Exhibits, 28R.
Outline of Projects, 31R; Progress of Year's Work, 31R; Variety
Test of Velvet Beans, 35R; Oat Variety Test, 36R; Plant Breed-
ing, 36R; Peanut Fertilizer Test, 38R; Sweet Potato Fertilizer
Test, 38R; Pasture and Lawn Grass Studies, 39R; Kudzu, 43R;
Winter Legumes, 43R.
REPORT OF CHEMIST........................................ ............................. 46R
Dieback of Citrus, 46R; Nutrition Studies, 48R; Sugar Cane In-
vestigations, 50R; Pecan Investigations, 50R; Soft-Pork Inves-
tigations, 50R; Tobacco Experiment, 50R.
REPORT OF PLANT PATHOLOGIST.................................... ...... 52R
Citrus Diseases Studied, 52R; Diseases of Tobacco, 58R; Dis-
eases of Truck Crops, 58R; Pre-Soak Method of Seed Treat-
ment in Relation to Germination, 59R; Mosaic Disease of Sweet
Potatoes, 59R; Irish Potato Seed Troubles in Florida, 1923, 60R;
Experiments with Seed Pieces of Irish Potato, 61R; Results
from Introduced Seed, 62R; Oertified Seed Increases the Yield,
63R; Late Blight Control by Spraying and Dusting with Copper-
Lime Dust, 63R; Dtseases of Plants Reported, 65R.
REPORT OF ENTOMOLOGIST.................... .......................... 103R
Insects of Citrus and Other Sub-tropical Fruits, 103R; Insects
of Truck Crops, 108R; Insects of Farm Crops, 110R.
REPORT OF ASSISTANT HORTICULTURIST............... ......................... 114R
Citrus, 114R; Grapes, 115R; Pecans, 115R; Tung-Oil Project,
116R; Miscellaneous, 116R.
Fertilizer Experiments, 119R; Dieback Experiments, 119R;
Variety Grove, 120R; Citrus in Quarantine, 120R; Nursery,
122R; Transplanting Citrus Seedlings, 123R; Solar Propagating
Bed, 123R; Improvements, 123R; Budget, 124R.
DISEASES ....................... ................. ....... ............... 125R
Improvements, 125R; Fertilizer Experiments with Tobacco,
126R; Tobacco Disease Investigations, 128R; Budget, 139R.

Hon. Cary A. Hardee,
Governor of Florida,
Tallahassee, Florida.
SIR: I have the honor to transmit herewith the annual report
of the director of the University of Florida Agricultural Exper-
iment Stations for the fiscal year ending June 30, 1923.
Chairman, Board of Control.

P. K. YONGE, Chairman-....-........------------ ----.------..Pensacola
E. L. WARTMANN---.......--....--.....--------------------Citra
J. B. SUTTON ......-...... --------..--........------------------..... Tampa
W. L. WEAVER ..-..................------- ..--------..... ..Perry
J. C. COOPER, JR...............--- ....------- ...-----.----.Jacksonville
J. T. DIAMOND, Secretary -.-------------------------..Tallahassee
J. G. KELLUM, Auditor...-------............----------Tallahassee

WILMON NEWELL, D.Sc., Director
JOHN M. SCOTT, B.S., Vice Director and Animal Industrialisi
J. R. WATSON, A.M., Entomologist
R. W. RUPRECHT, Ph.D., Chemist
0. F. BURGER, D.Sc., Plant Pathologist
W. E. STOKES, M.S., Assistant Grass and Forage Crop Spe.
A. H. BEYER, M.S., Assistant Entomologist
C. E. BELL, B.S., Assistant Chemist
J. M. COLEMAN, B.S., Assistant Chemist
G. F. WEBER, Ph.D., Assistant Plant Pathologist
HAROLD MOWRY, Assistant Horticulturist
T. VAN HYNING, Librarian
MARY E. ROUX, Mailing Clerk
A. W. LELAND, Farm Foreman
K. H. GRAHAM, Auditor
RETTA MCQUARRIE, Assistant Auditor
W. B. TISDALE, Ph.D., Assistant Plant Pathologist, Tobacco Ex
periment Station (Quincy)
JESSE REEVES, Foreman, Tobacco Experiment Station (Quincy:
J. H. JEFFERIES, Superintendent, Citrus Experiment Statiol
(Lake Alfred)

Report for the Fiscal Year

Ending June 30, 1923

Hon. P. K. Yonge,
Chairman, Board of Control.
SIR: I have the honor to transmit herewith my report on the
work and investigations of the University of Florida Agricultu-
ral Experiment Stations, together with the reports of the heads
of the several departments, for the fiscal year ending June 30,
1923; and I request that you transmit the same, in accordance
with law, to His Excellency, the Governor of Florida.


The fiscal year just closed has been the second year of the
biennium and the resources of the Station have been practically
the same as during the preceding year. Any considerable expan-
sion of the work under way has, accordingly, been impossible'
but the results of the increased appropriation made by the last
legislature are becoming evident. The lines of investigation are
now better provided for than formerly and work on the various
projects is proceeding in a highly satisfactory manner.
The financial resources of the main station at Gainesville, for
the fiscal year just closed, have been as follows:

Year ending
June 30, 1923
Adams Fund................................... ............................... $15,000.00
Hatch Fund.-................... .......................... ...15,000.00
State Appropriation....................... ..................... ........30,000.001
Proceeds from sales.................................................... 6,617.51
Less amount expended account Citrus
Experiment Station at Lake Alfred........................ 5,330.00
Total .................................. ................. $61,287.51

Florida Agricultural Experiment Station


The soft-pork investigations which have been carried on for a
number of years were continued. There now seems to be sufficient
evidence to show that feed is not the only factor that may change
the melting point of fat. Breeding experiments had been begun
which were intended to show whether or not heredity affected the
melting point. Because of disease among the pigs which were
being used there was no conclusive data along this line. There was
marked difference in the melting point and degree of hardening
of pigs out of the same litter which had been given the same
feed and treatment. It had been stated often that pigs stunted
in growth showed a lower melting point, but this was not the
case, as some of the smallest pigs had the highest melting points.
Another point which had been argued was that hogs making the
most rapid growth showed a low melting point. This, likewise,
did not seem to be true. As pigs grow older the melting point of
the fat is increased and there seemed to be no definite rate of in-
crease or no correlation of rapidity of gain to the melting point.
The original sow from which the breeding experiments were
started will be used in producing other litters and in carrying this
work forward.
In some pig feeding experiments carried on it was found that
rations of shelled corn, tankage and peanut meal, containing pro-
tein from both animal and vegetable sources, made the best gain.
Those fed shelled corn and tankage with the protein from animal
sources gave the second best gain. The animals fed shelled corn
and peanut meal, with'the protein from vegetable sources, gave
less than half the gain of either of the others. And finally, hogs
fed shelled corn only gave virtually no gain.
In experiments on feeding the dairy herd it was found that
corn silage in connection with a well-balanced grain mixture
showed a larger milk yield than did sorghum silage, and that
Japanese cane silage in connection with the grain ration gave
a decidedly better milk yield than did Napier grass silage.


The work of introducing and testing grasses and forage crops
is carried on in cooperation with the Bureau of Plant Industry, of

Annual Report, 1923

the United States Department of Agriculture, and many of the
plants tried out were introduced by that department.
Probably the most outstanding results, referring to the intro-
duction and trial of forage plants was shown by Bahia grass
(Paspalum notatum). It has been tested in nearly every county
in the state with good results. Dallis grass (Paspalum
dilatatum) and Vasey grass (Paspalum larranagai) seem
to be two of the best all-the-year, wet-heavy-land pasture
grasses, since they are seldom killed by Florida's mild winters.
Several species of Crotalaria have been under observation for
a number of seasons and are now giving promise of being valu-
able additions to the state's list of green-manure and grove-cover
crops, particularly for orange and pecan groves. At least one
has been tried in a number of orange groves on the east coast
with good results. Stock do not seem to relish Crotalaria, hence
there is no temptation to feed it rather than use it as a cover
crop or green manure.
The breeding work on Spanish peanuts continued to give
gratifying results. No high-yielding strains are yet ready for
distribution, but 20 are now in the midst of the final stage of
testing and one or more high-yielding strains should soon be
available for distribution.
Of the various plants being tested for pasture purposes, Ber-
muda grass (Capriola dactylon), Carpet grass (Axonopus com-
pressus), Dallis grass (Paspalum dilatatum), Bahia grass (Pas-
palum notatum), Vasey grass (Paspalum larranagai), Para grass
(Panicum barbinode) and Centipede grass (Eremochloa ophiur-
oides) appear most promising. Lespedeza or Japanese clover
(Lespedeza striata) still is the best permanent-pasture legume.
The work on lawn grasses has thus far been to study the
various varieties and to determine the effect of sowing northern
grasses on these varieties in fall to give green lawns in winter.
Of the grasses thus far showing special promise for lawn pur-
poses, St. Augustine (Stenotaphrum secundalum), Centipede
(Eremochloa ophiuorides), St. Lucie (Capriola dactylon, var.
St. Lucie) and Bermuda (Capriola dactylon) stand out promi-
nently in the order named. Ordinary Carpet grass sodded over
(Lolium italicum), Red Top (Agrostis alba), and White clover
slowly but once sodded made a satisfactory lawn. Italian rye

Florida Agricultural Experiment Station

(Trifolium repens), fall sown on various lawn grasses made sat-
isfactory fall, winter and spring growth, but showed a tendency
to retard the spring growth of the southern grasses. This ten-
dency is less pronounced with St. Augustine grass (Stenota-
phrum secundatum), Centipede grass (Eremochloa ophiuroides),
the Bermudas (Capriola dactylon) and Bahia grass (Paspalum
notatum), than with some of the others.


The study of dieback of citrus trees was continued thru the
year. In the young grove at Lake Alfred some dieback developed
early in the season, apparently due to over feeding. The amount
of nitrogen was reduced and the trees quickly recovered. An
analysis of the soil under the affected trees, as well as those that
appeared perfectly healthy, was made, but no material differences
were noticed.
In a study of the drainage water from the tanks which have
been used at Gainesville the following definite observations were
made: (1) Trees receiving their ammonia from manure,
showed the smallest amount of drainage. (2) The study of
total solids and fixed solids removed, showed that the mineral
sources of ammonia cause greater loss of salts than do organic
sources. (3) Sulphate of ammonia causes increased loss of cal-
cium or lime and potash, as well as aluminum, while the nitrates
caused increased loss of sulphates, and manure exerted a strong
protective action on all soluble soil salts, as was shown by the
small amount of fixed salts removed from these two tanks. While
the results cannot be considered as final, they show the benefit to
be derived from increased amounts of humus and organic matter
in a soil in retaining soil fertility.
Studies as to the effect of high- versus low-potash fertiliza-
tion were carried on and analyses of fruit were made from trees
with high- and low-potash fertilization, but this experiment has
been running too short a time to state definite conclusions.
In a summary of the work done on the various forms of phos-
phoric acid during the, last five years, it was found that no one
source of phosphoric acid would give a higher yield or better
quality of fruit.


Annual Report, 1923

Studies of melanose and stem-end rot were continued. Eleven
experiments which were carried on during the spring of 1922
to test the effectiveness of 3-3-50 bordeaux mixture plus
1-percent oil emulsion were made on a total of 1,255 acres, in
practically every important citrus-producing area of the state.
One application of the spray was made, ranging from 10 to 20
days after the blossoms had fallen, and no more sprayings were
given except in some instances where oil emulsion was used later
against scale insects and whitefly and where sulphur dust was
used for the rust mite. The average acre cost of this spraying
ranged from 8 to 13 cents, depending on the nearness to the
water supply. A careful check of results indicated a profit gain
of 50 cents a box, estimates being based on the relative prices
of bright, golden and russet grades of oranges.
In the investigations of citrus canker, which were begun in
the preceding year, the following important observations were
(1) Citrus seed infected with the citrus canker organism did
not produce canker-infected plants.
(2) The longest time the organism was observed to live in
unsterilized soil was one week.
(3) The organism lived and remained viable for many months
on sterilized pine shavings.
(4) It was observed to live for some time in both sterilized
distilled water and tap water.
In vegetable-seed treatment it was shown that corrosive subli-
mate (1 to 1000) is better as a disinfectant when applied to the
dry seed for five or ten minutes than when applied after the seed
have been soaked in water four or five hours.
The following results were obtained from experiments to
control late blight on Irish potatoes: Copper-lime dust, con-
taining 6 percent of metallic copper, resulted in an increase in
yield of 25 percent over untreated plots. Bordeaux paste gave
approximately the same results, but was more expensive than
the copper-lime dust. Homemade bordeaux mixture gave approx-
imately the same control and cost $10 an acre less than the
copper-lime dust.

Florida Agricultural Experiment Station

Probably the most noteworthy result of last year's work of
this Department was the outstanding success in the control of
nematodes by the use of bunch velvet beans with constant cul-
tivation including one or two hoeings. By this method in a single
summer the number of nematodes in the soil was reduced as
thoroly as usually is obtained by growing resistant crops on
the land for two or three years. The land being treated by
this method during the summer after the crop has been harvested
is available for cropping another year, and, hence, the land
may be kept in use during each trucking season. 'While the
preliminary work was done the previous year, the work of last
year demonstrated it as a striking success.
Last year's experiments on citrus thrips (Frankliniella tritici
bispinosa) were continued, and, corroborating last year's results,
it was found that 25 thrips to the bloom are dangerous for
oranges, that the dangerous number of thrips for grapefruit
would be higher and for tangerines lower. In groves where the
Spanish needle (Bidens leucantha (L.) Willd.) was allowed to
grow it was useless to spray for thrips, because the citrus blos-
soms were reinfested from the Spanish needle blossoms, which
averaged as many thrips as the former. Extensive dusting ex-
periments were carried on for the control of these pests but they
proved unsuccessful except on satsumas. On round oranges and
grapefruit in southern Florida the fog of nicotine dust in the
trees did not penetrate the blossoms sufficiently to kill the thrips,
while in the satsuma belt the trees were small 'and a person could
use a hand duster and apply the dust more directly to the blos-
Last season recorded the most serious infestation of mealy
bugs in citrus trees for a decade. Ordinary oil emulsions, such
as are used against scale and other insects, proved only 50
percent efficient in the control of this pest. The oil did not pen-
etrate the mass of mealy bugs between the fruit and cluster with
sufficient thoroness to do effective work. Lime-sulphur solution
(1 to 65), a 1 percent solution of carbolic acid and kerosene emul-
sion at the rate of 1 gallon to 15 of water, applied with at least
250 lbs. pressure, all gave better results than did the oil emulsion.
Probably the most satisfactory solution of all was one of nicotine
sulphate and soap, 1 quart of the former and 6 or 8 pounds of soap
to 200 gallons of water.


Annual Report, 1923

Continuation was made of previous studies of thrips; one of
the new developments of the season was the heavy damage done
to snap beans. The thrips fed on the leaves causing them to wrin-
kle and curl up and they were often injured so heavily that they
would drop to the ground.
Harold Mowry commenced work as assistant horticulturist
on October 2, 1922, succeeding Gustav Umlauf, deceased.
From experiments carried on during the year in connection
with Aleurites fordi, Hemsl., tung-oil trees, it was determined
that the seed should be planted late in January or February to
avoid frost injury to the young plants the following autumn;
that ordinary methods of propagation by cutting have proved
almost a complete failure; that both patch and sprig buds made
good unions and subsequent growth; and that it is infested with
cottony cushion scale and nematode. Propagation by means of
budding is considered important because of the tree's inconsis-
tency in bearing.
The test vineyard of bunch grapes, comprising largely var-
ieties or hybrids of the Vitis aestivalis group were increased to
44 varieties and a material beginning was made in the planting
of a variety pecan orchard of the following varieties: Alley,
Bradley, Curtis, Moneymaker, Moore, President, Schley, Stuart
and Success.
Other fruits which were introduced during the year included
pears, blueberries and several types of Nessberry (which was
originated by Professor H. Ness, of the Texas Agricultural Ex-
periment Station).
A number of blocks were set aside for trial test of ornamental
plants and a small beginning of plants were introduced to begin
this planting. This planting is to be made up largely of plants
suitable for hedges, borders and for general ornamental planting
in Florida.
The equipment of the grounds had run down and a great deal
was needed in the line of new greenhouses, slathouses, propa-
gating beds, etc. Slight improvements which were made during
the year consisted of another line of overhead irrigation, a com-
plete system of underground water mains for spraying and
irrigating purposes thruout the citrus grove and nursery, and
other minor supplies and equipment. This equipment, however,
falls far short of the needs of the horticultural grounds.


Florida Agricultural Experiment Station

The Station's library, due to inadequate funds, made prac-
tically no acquisitions, during the year, other than such govern-
ment and state publications as are distributed free of charge.
Despite the fact that the library is extensively used, it has not
been possible to employ a librarian for more than half time.
This has greatly delayed the proper cataloging and indexing of
literature and it has not, therefore, been as accessible as desired.
By rigid economy it has been possible to bind a small portion
of the literature accumulated, and there are now 3,977 bound
volumes of government and state publications, journals and
periodicals in the library. There still remain many volumes to
be bound, but until shelves and space can be had it will be diffi-
cult to make accessible many of these publications.
In addition to editing all of the bulletins, press bulletins and
other publications of the Experiment Station during the year,
the editor edited 160 articles, covering a total of 15,060 words
and prepared 104 articles covering a total of 27,360 words, on
the various phases of agricultural work in the Station. Most
of these articles were distributed widespread to the press of
the state thru the Agricultural News Service which is maintained
by the Agricultural Extension Division. He is a part time em-
ployee of the Station.
During previous years the fundamental equipment for this
station had been obtained and 21 acres of land put under culti-
vation. Four and a half acres had been used to test the high
and low potash content of fertilizers. This grove was well
cared for during the year and it made splendid growth in spite
of the severe drought in the spring. This drought caused a
wilting of leaves almost to the dropping point, but after the
summer rains began late in May, a June bloom appeared and
a good crop of fruit was harvested.
A ten-acre grove was devoted to experiments to determine the
cause and control methods for dieback. This grove also made
splendid growth and received good care thruout the season.
This work is being carried on by R. W. Ruprecht, chemist, and
the nature of the experiment is such that results cannot be ex-
pected for a number of years.


Annual Report, 1923

Two acres are devoted to a variety grove, the primary object
of which is to show the difference in growth and bearing quan-
tity and quality of the standard varieties of citrus fruit when
budded on rough lemon, sour orange, grapefruit and other stock.
This grove is in good condition but as yet is young.
The bud-supply progeny grove is made up of trees from buds
taken from the best trees of the standard citrus varieties. This
grove is growing nicely and should be of unusual value to growers
in the future as a source of supply for choice budwood.
In addition to the above lines of work, a number of citrus
varieties and other varieties have been introduced from all parts
of the world. They are held in quarantine for a certain period
of time. It is possible that some of them have particular merit
for rootstock or other purposes. A small nursery is maintained
to meet the needs of the station grounds, and probably the
most interesting work of the year was the propagation of nur-
sery stock from cuttings. This method appears to have some ad-
vantage over the seed method and allows careful culling at the
time of transplanting. This propagation is carried on in a
solar propagating bed, which is so constructed as to give bottom
heat by utilizing the sun's rays to advance the rooting of the
During the year 1922-23 two and a half acres of shade were
completed, under which two and one-fifteenth acres are devoted
to fertilizer experiments to determine the effect upon cigar leaf
tobacco of different amounts of potash and phosphorus from
different sources used in combination with different amounts of
manure. The remaining is included in turn rows and spaces
between these plots. This shade is modern and was built at
a total cost of $1,172.81.
A tobacco barn, adequate to store and cure the tobacco pro-
duced under the shade described above, was built. The total
cost of this barn, inclusive of 15,000 tobacco sticks for curing,
was $1,614.19.
Other improvements during the year consisted of the build-
ing of a negro laborer's cabin at a cost of $313.17, the building
of a garage and the purchase of various tools and equipment
necessary for the proper operation of the station. Near the
close of the year materials were purchased for the construction
of a greenhouse at a cost of $841, this greenhouse being necessary

Florida Agricultural Experiment Station

for space to carry on work in connection with plant disease work.
It is to be used immediately in an effort to seed, during the winter
months, some of the strains of tobacco resistant to black shank
so as to have it available for distribution in the spring.
In addition to the fertilizer experiments mentioned above,
the chief work of this station has been to investigate tobacco
diseases. It appeared from observations in the field that certain
plants, embracing many strains of Big Cuba, are resistant to
black shank. These plants were selected carefully for seed to
be used in propagating strains of tobacco which are resistant
to black shank, and at the same time to retain high yield, tex-
ture, aroma and burn. This work apparently is meeting with
much preliminary success, and attention is called to the detailed
account given in the report of the assistant plant pathologist who
has charge of the station.
As stated in the last report, this branch station was provided
for by Act of the Legislature (Chapter 8442) approved June
24, 1921, and consists of 160 acres of Everglades land located
in Section 3, Township 44 South, Range 37 East, in Palm Beach
During 1921, main ditches were made thru the property under
the direction of F. C. Elliott, chief engineer of the Everglades
Drainage District.
There are now under construction on the property two frame
buildings, each two-story in height, one of which will be used as
a residence by the foreman and the other as an office and labora-
tory building. With the completion of these buildings and the
completion of a hard-surfaced road to the property from West
Palm Beach, actual experimental work can be prepared for,
something practically impossible prior to this time, owing to the
inaccessibility of the tract and the absence of shelters or living
quarters of any description.
No expenditures have been made, since July 1, 1922, out of
the general revenue appropriation, the status of this fund on June
30, 1923, being as follows:
Appropriation for year ending June 30, 1922..............$10,000.00
Appropriation for year ending June 30, 1923.............. 10,000.00
Expenditures, 1921-22, previously reported.................. 34.49
Balance, June 30, 1923..............................................$19,965.51


Annual Report, 1923

G. F. Weber was appointed assistant plant pathologist on July
1, 1922. Harold Mowry commenced work as assistant horticul-
turist on October 2, 1922, succeeding Gustav Umlauf, assistant
horticulturist, who died on June 10, 1922.

Following is a list of the publications issued by the Experi-
ment Station during the fiscal year ending June 30, 1923:
No. Title Pages Edition
165 A Preliminary Report upon an Improved
Method of Controlling the Boll Weevil....72 20,000
166 Tobacco Diseases in Gadsden County in
1922, with Suggestions for Their Pre-
vention and Control--.........................-...........48 3,097
167 Preliminary Report on Controlling Melan-
ose and Preparing Bordeaux-Oil.--...................20 20,603

Totals -...-------.------............-.....-..... ...--.--- .140 43,700
No. 165, A Preliminary Report Upon an Improved Method of
Controlling the Boll Weevil: (Geo. D. Smith), pp. 72, figs. 13. An
improved method of boll weevil control is described, consisting
of clearing the fields early in June of all adult weevils and at
the same time destroying their eggs and larvae, thus leaving
the cotton plants free to develop squares and bolls without weevil
interference for the succeeding seven or eight weeks.
There are two distinct operations included in this method.
The first is stripping the squares from the plants about June 5,
by which date practically all weevils are out of hibernation. The
squares are destroyed, together with any fallen squares, insuring
the.destruction of all immature weevils.
The second operation consists in applying the poison, prefer-
ably calcium arsenate, to the buds of the plants. The few adult
weevils that were missed when the squares were stripped, are
killed within approximately three days. By the time reinfesta-
tion occurs the treated field will have normally set practically
a full crop of cotton. By the time of the annual summer migra-


Florida Agricultural Experiment Station

tion, July 25 to August 1, upland cotton bolls which are more
than half grown at the time of migration will have succeeded
in maturing and opening, as the migrating weevils which arrive
late in July, turn to the squares and do not attack the green bolls
to any extent.
No. 166, Tobacco Diseases in Gadsden County in 1922, with
Suggestions for their Prevention and Control: (W. B. Tisdale),
pp. 48, figs. 15. A summary of the available information on
diseases affecting tobacco in Florida, with certain observations
on black shank, caused by the organism Phytophthora nicotianae
de Haan, which was isolated and described by the author. Rem-
edies suggested are the avoiding of introducing infected plants,
prohibiting the use of tools and material from infested fields,
prohibiting the passage of laborers or animals from one field to
another, avoiding drainage water from infested fields, and the
development of resistant varieties of tobacco.
Among other diseases which were described is mosaic. No
causal agent for this disease has yet been found. Control meas-
ures recommended are the use of beds which are free from the
disease, destroying certain weeds from around the shade, and
pulling out of infected plants as soon as discovered.
Root-knot, caused by Heterodera radicicola, Atkinson: This
can be controlled by cultivating constantly and by introducing
only plants from the seedbed free of the disease, by growing
crops on the land when not in tobacco which are resistant to its
attacks, such as velvet beans, Iron and Brabham cowpeas, etc.
Wildfire, caused by Bacterium tabacum Wolf & Foster: The
control recommended for this disease was production of healthy
seedlings by, first, disinfecting the seed before planting, second,
not using cloth over the seedbeds from infected areas, third,
watching the plants in the bed and if doubtful spraying or dusting
once a week until set in field. If the disease appears in the field
on only a few plants they should be pulled out when dry and re-
placed with healthy ones. If the whole field shows early infec-
tion, destroy entirely and start in with healthy plants a week
or ten days later.
Granville wilt, caused by Bacterium solanacearum E. F. S.:
For the treatment of this disease shallow cultivation and the
cutting of as few roots as possible were suggested, because one
may reduce the wounded portions of the roots.
Leaf spot, caused by Phyllosticta nicotianae E. & E., frog-eye


Annual Report, 1923

or speakingg," caused by Cercospora nicotianae E. & E., and
root-rot were also discussed and certain recommendations made
as to avoiding the obtaining of infected plants.
No. 167, Preliminary Report on Controlling Melanose and
Preparing Bordeaux-Oil: (0. F. Burger, E. F. DeBusk and W.
R. Briggs), pp. 20, figs. 5. A detailed discussion of melanose and
stem-end rot of citrus caused by a fungus Phomopsis citiri Faw.
Numerous experiments were carried on in cooperation with
county agents and growers in various counties, and splendid
results were obtained by spraying with 3-3-50 bordeaux mixture
to which 1 percent'of oil emulsion had been added. Application
was made from 10 to 20 days after the blossoms had fallen. Fruit
from all groves under experimentation were graded carefully.
Great improvement in the grade over the check plots was noted.
Various methods of making bordeaux mixture were stressed and
particular emphasis placed on mixing dilute solutions of copper
sulphate and lime.

No. Title Author
341. List of Reports and Bulletins on Hand--.......Sept. 15, 1922
342. Green Spotting of Citrus Fruit.-......----O. F. Burger and
E. F. DeBusk
343. Black Rot of Oranges............---...........-....0. F. Burger and
Wm. Gomme
344. Cottony Cushion Scale---................................J. R. Watson
345. Controlling Poultry Lice-...--......-..--...--...-.....- J. R. Watson
346. Entomogenous Fungi on Citrus---...................J. R. Watson
347. The Control of Rust Mites....---.......................--J. R. Watson


20R Florida Agricultural Experiment Station


Wilmon Newell, Director.

SIR: I respectfully submit the following report of the credits
received and expenditures vouchered out of funds as specified
during the fiscal year ending June 30, 1923:


Adams ..........................................-.... ..........-....
Hatch ......................... J ........... ...... ................
State Appropriation,
Main Station ..............................-... $7,478.27
Substations .......-...... ..::.-........--..... 15,799.25
Sales Fund ............................................... 593.72


Labor ..
Freight a
Heat, lig
Seed, pla
Tools, mT
Live stock

................................................... 991.341
ons ............................................ 28.00
and Stationery ................-....... 84.16
nd Express .............................. 19.77
ht, water, and power............ 21.05
s and laboratory supplies .... 237.40
nts and sundry supplies ........ 197.27.
rs ....................... --................. 349.93
stuffs ....--....................-.............--------------.....--- 499.95
................................................... 243.24
machinery and appliances ........ 92.45
e and fixtures .......................... 175.11
apparatus and specimens.... 31.32
-k ........................................ ... ............
g expenses .............................. 363.00
at expenses .......-----.................... .58
Sand land ................................ 291.76
............................. .......... .01
















Annual Report, 1923

Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Animal Industry for the fiscal year ending June 30, 1923.
Animal Industrialist.
Study of the soft-pork problem and feeding experiments with
swine and the dairy herd have constituted the major work of
this department this year.

The soft-pork studies carried on this year were a continua-
tion of the breeding experiment mentioned in the last annual re-
port. Twelve sows and three boars were used in the experiment.

Fig. 2.-Majesty's Noble Lassie 492336, Grand Champion Jersey cow at
the Florida State Fair (Jacksonville), 1922; also Grand Champion Jer-
sey cow at the South Florida Fair (Tampa), 1923.
These animals are pigs from the original three sows and one
boar used at the beginning of the breeding experiment. During
the year these hogs were all fed alike, the ration being made up of
corn and shorts, equal parts by weight, plus a little whole milk.
For detailed results as to pig number, weight, melting point



Date, June 28, 1922 Date December 6, 1922

1 ..................... Female 73.3 29.5 75.79 185.0 111.7 35.4 +5.9 77.88
h .s I

S F 1.3 3.0 7.
10...................... Female 5573.3 29.9 66.7 185.0 70.0 35.4 +5.9 77.88
11...................... Female 3.3 30.3 75.20 135.0 76.7 39.0 +7.1 71.94
312............. Male 48.3 28.9 70.00 170.0 121.7 38.0 +9.1 73.92

413............... Female 50.0 28.6 70.15 120.0 70.0 34.5 +5.9 77.48
514...................... Female 53.3 28.0 75.50 115.0 9361.7 35.4 +7.4 77.08

8............-... Female 18.3 32.0 71.75 died

15............. Female 51.6 31.8 70.50 130.0 78.4 37.4 +5.6 75.50
10.................... Female 55.0 33.9 66.75 125.0' 70.0 35.7 +1.8 77.88
11...................... Female 43.3 30.3 75.20 120.0 76.7 33.3 +3.0 76.70
12...................... Male 48.3 29.6 74.38 130.0 81.7 35.8 +6.2 77.00
13...................... Female 58.3 35.3 66.87 165.0 106.7 37.5 +2.2 73.92
14...................... Female 46.6 31.0 72.50 140.0 93.4 36.3 +5.3 75.90
15...................... Male 55.0 30.7 74.58 190.0 135.0 36.6 +5.9 75.60
16.... .........Male 53.3 29.5 73.34 160.0 106.7 34.8 +5.3 75.45
17...................... Female 55.0 29.6 78.40 165.0 110.0 37.5 +7.9 74.32
18.................. Female 36.6 32.0 70.00 135.0 98.4 35.4 +3.4 76.00

Annual Report, 1923

of fat, iodine number, and the difference in the melting point of
fat at different dates, see Table 1.
In some respects these figures are interesting. In the first
place, they show a marked difference in the melting point of
fat of pigs in the same litter when they are all fed and cared
for alike. They show that as the pigs grow older the melting
point of the fat is higher. They also show that there is a marked
difference in the degree of hardening of fat of pigs in the same
litter when fed on the same feeds. For example compare the
change in melting point of fat of pigs No. 3 and No. 6 from
June 28, 1922, to December 6, 1922. Orr compare No. 1 and No.
6. The melting point of fat of No. 3 was.raised 9.1 degrees C.
During the same time and under exactly the same conditions the
melting point of fat of No. 6 was raised only 1.9 degrees C.
In the case of No. 1 the melting point of fat was raised 5.9 de-
grees C. Many more comparisons might be made. There
seems to be sufficient evidence to show that feed is not the only
factor that may change the melting point of fat of hogs.
The above records of 17 hogs show that when all were fed on
the same feeds and kept under exactly the same conditions for
five months, there was a difference of as much as 7.2 degrees C.
in the melting point of fat of pigs of the same litter.
Some authorities in the past have said that pigs stunted in
growth would have a low melting point. The records in Table
1 do not bear this out. Some of the smallest hogs have the high-
est melting point of fat. Some have argued that the hog which
makes the most rapid gain will have a tendency to be soft. In
this case there does not seem to be any correlation between
rapidity of gain and the melting point of fat. It does seem true
that as the pigs grow older the melting point of fat is increased.
But there seems no definite rate of increase.
These hogs were mated, as shown below, so that the sows would
farrow during March and April 1923. Sows No. 2, 9, 10, 11, 13,
14, and 18 were mated with boar No. 3. Sows No. 4, 7, and 17
were mated with boar No. 6. Sows No. 1 and 5 were mated
with boar No. 16.
All of the sows farrowed in the spring ,of 1923. During the
latter part of May one litter of pigs became stunted and did
not do well. Since it was thought that the trouble was probably
due to worms all hogs on the farm were given oil of chenopodium


Florida Agricultural Experiment Station

as a vermifuge. A few days later one or two of the pigs in this
particular litter died. On post-mortem examination no lesions
typical of any particular disease were found. About June 1
a litter of older pigs became sick and died and upon post-mortem
examination lesions typical of necrobacillosis, or necrotic enteri-
tis, were very pronounced. All of the infected pigs were treated
with sodium hyposulphite, a drug supposed to be useful in treat-
ing this disease. Losses continued, and all the animals were
vaccinated June 22-28 for hog cholera, swine plague, and necrotic
As a result of this infection all pigs from the sows in the experi-
ment, one boar, and two sows were lost. The work, however, is
being continued, and the remaining sows will be bred to farrow
in the fall of 1923.
Another angle of the soft-pork problem was undertaken. This

Fig. 3.-Florida Lasifaso 181522, winner of first prize Jersey bull over
two years and under three years, South Florida Fair (Tampa), 1923.

was to study to what extent the problem is prevalent in states
farther north. Arrangements were made with Armour & Com-
pany of Chicago to have samples of fat taken from carcasses in
their cooler in Chicago and sent to the laboratory here so that
the melting point of the fat could be determined. The first lot
of 20 samples was received June 14, 1922, and the second lot of
19 samples was received November 25, 1922. The following
figures give the melting point of fat of each sample, June 14,


Annual Report, 1923

Sample Melting point,
No. degrees C.
1 .......................................35.9
2 ....... ....... .... ................29.8
3 ..................................30.0
4 ..............................- .... 27.2
5 ....................................38.0
6 ...............................----.... 36.2
7 .......................- ...... 36.3
8 ..-........................ 37.7
9 ....... .............. ............ 29.6
10 ............... ................ 37.9

Sample Melting point,
No. degrees C.
11 .............. ..........................37.0
12 ................. ...........- 38.8
13 ..................... ............. 32.5
14 .........--------........................ 34.0
15 .......................---....... 32.5
16 ............ -.... ..-........--- 37.4
17 .........................-... ....... 39.6
18 ................................... 39.8
19 ............--.------.............39.2
20 .... -----........................-- ---39.2

The following figures give the melting point of fat of each
sample, November 25, 1922:

Sample Melting point,
No. degrees C.
1 .................. ..................35.9
2 -.... ............................ 35.6
3 .........---....................... 38
4 ................. ...-............. 31.7
5 ............................. 35.0
6 ......---............................ 31.7
7 .... .......................... 36.1
8 ....................................-37.2
9 ................ .................. 37.7
10 .............. ..-................ 34.9

Sample Melting point,
No. degrees C.
11 ..................... ........ 38.7
12 .............. ...----------.. 39.0
13 ...................-.....------- .32.8
14 ........................................
14 ------.-----------.--.-- .......---- ----- 34.9
15 ------..................................----37.3
16 .... .............. -----......--- 37.5
17 -----................... ---........... 28.8
18 ........................-----...3-- 0.7
191 ...............--..................-- -29.3

It will be seen from these figures that softness of fat of these
hogs is indicated.
This experiment was conducted with 40 pigs. They were
divided into four lots of ten pigs each. The pigs were not all
of the same size, but the bunch was divided into four lots as
nearly equal in size and weight as possible.
Each lot was weighed on three consecutive days and the average
of the three weighing was taken as the weight at the beginning
and close of the experiment. The feeding experiment began
December 8, 1922, and continued until March 9, 1923.
The four lots of pigs were fed as follows:
Lot I, shelled corn only.
Lot II, shelled corn, tankage and peanut meal as follows: to
each 20 pounds of shelled corn, 1 pound of peanut meal and 1
pound of tankage were added.
Lot III, shelled corn and tankage as follows: to each 10
pounds of shelled corn 1 pound of tankage was added.
Lot IV, shelled corn and peanut meal as follows: to each 10
pounds of shelled corn 11-3 pounds of peanut meal were added.
Weighings were made every 30 days and the gains recorded.
Table 2 gives the weights at beginning, weights at close, gains
made during the test and the average daily gains to the animal:


Florida Agricultural Experiment Station

Lot I, Lot II, Lot III, Lot IV,
pounds pounds pounds pounds
Weight at beginning of
experiment, Dec. 8, 1922........ 986.6 1013.3 1000.0 995.0
Weight at close of
experiment, Mar. 9, 1923........ 1070.0 1813.0 1786.6 1338.0
Gain in 90 days........................ 83.4 799.7 786.6 343.0
Average daily gain...................... .090 .888- .874 .381

Lot I made no gain at all, while Lot II and Lot III made fairly
satisfactory gains. Lot IV made very little gain.

The object of these feeding tests was to secure reliable data
as to the value of the different feeds for milk production. The

Fig. 4.-Florida's Majesty Jewel 443862, winner of second prize Jersey
cow over three and under five years, South Florida Fair (Tampa), 1923.
first test was a comparison of corn silage and sorghum silage
for milk production.
On September 15, 1922, eight cows were selected for the test
and divided into two lots of four cows each. Due consideration
was given in the selection of each lot so that the lactation periods
of all were as nearly equal as possible.


Annual Report, 1923

Lot I was made up of cows No. 20, 81, 83, and 120. Lot II
was made up of cows No. 85, 113, 141, and 159.
All cows were fed the same grain mixture thruout the feeding
test, the grain mixture being as follows:
W heat bran............................................. ..................100 pounds
Cornmeal .................................... ..---.....---. ----100 pounds
Ground oats.................................. ............... 75 pounds
Bright cottonseed meal.................................. 100 pounds
Alfalfa meal..................... ...... ............. 50 pounds
Each of the cows was fed about twelve pounds a day of the
above grain mixture. The only difference in the feeding of Lot I
and Lot II was that during the first period, September 15 to
October 24, the cows in Lot I were fed corn silage and the cows
in Lot II were fed sorghum silage. During the second period,
October 26 to November 29, cows in Lot I were fed sorghum
silage and those in Lot II were fed corn silage.
The following figures show the pounds of milk produced during
each period by both corn silage and sorghum silage:
First period, September 15 to October 24, 1922,-
Corn silage, milk produced, pounds................. ..... 3,484.2
Sorghum silage, milk produced, pounds ............... ....2,677.9
Second period, October 26 to November 29, 1922,-
Corn silage, milk produced, pounds ............ ...........1,963.9
Sorghum silage, milk produced, pounds............. .....2,325.4
When corn silage was fed the total milk produced was 5,448.1
pounds. When sorghum silage was fed the total milk produced
was 5,003.3 pounds, or a difference of 444.8 pounds in favor of
the corn silage.
The second feeding test was a comparison of the feeding value
of Napier grass silage and Japanese cane silage for milk produc-
On January 1, 1923, eight cows in the dairy herd were selected
and divided into two lots of four each. Due consideration was
given in the selection of each lot that the lactation periods of all
were as nearly equal as possible.
Lot I was made up of cows No. 20, 81, 83, and 120. Dot II
was made up of cows No. 59, 98, 113 and 149.
All cows were fed the same grain mixture thruout the feeding
test, the grain mixture being as follows:
Wheat bran ..................................................100 pounds
Cornmeal .-------------------..................................... 100 pounds
Ground oats....................................................... ........ 75 pounds
Bright cottonseed meal.......................................100 pounds
Alfalfa meal............ ......................................... ...... 50 pounds


Florida Agricultural Experiment Station

Each cow was fed about 12 pounds a day of this mixture.
The only difference in the feeding of Lots I and II was that
during the first period of the test, January 1 to 30, the cows in
Lot I were fed Napier grass silage and cows in Lot II were fed
Japanese cane silage. During the second period, February 3 to
March 4, cows in Lot I were fed Japanese cane silage and cows
in Lot II were fed Napier grass silage. During the third period,
March 8 to April 6, the cows in Lot I were fed Napier grass silage
and the cows in Lot II were fed Japanese cane silage.
During the progress of the experiment it was noted that the
cows fed Napier grass silage did not eat the silage as well as they
did Japanese cane silage. One silage looked as good as the other,
but there was a marked difference in taste and smell. Napier
grass silage has quite a different odor and different acid flavor.
The acid odor and flavor of Napier grass silage is not so pro-
nounced as in Japanese cane silage.
The following figures give the pounds of milk produced during
each period and the total amounts of milk produced by Japanese
cane silage and Napier grass silage.
First period, January 1 to 30, 1923,-
Napier grass silage, milk produced, pounds......................1,396.2
Japanese cane silage, milk produced, pounds...................1,758.3
Second period, February 3 to March 4, 1923,--
SNapier grass silage, milk produced, pounds,..................1,790.8
Japanese cane silage, milk produced, pounds----......................1,658.0
Third period, March 8 to April 6, 1923,-
Napier grass silage, milk produced, pounds.........................1,565.5
Japanese cane silage, milk produced, pounds................1,671.0
When Napier grass silage was fed the total of the milk pro-
duced in the three periods was 4,752.5 pounds. When Japanese
cane silage was fed the total of the milk produced in the three
periods was 5,087.3 pounds, or a difference of 334.8 pounds in
favor of the Japanese cane silage. The difference is so small
that from the results of this one test it seemed that there is
little difference in the value of these two silage crops for milk
The dairy and beef herds owned by the Florida Agricultural
Experiment Station were exhibited at the State Fair at Jackson-
ville, November 17-25, 1922.
The following prizes were won:
Jersey bull, 3 years and under 4..........................:.......First prize


Arnual Report, 1923'

Jersey senior bull calf.......----..............------------Second
Jersey cow, 4 years and over-.......-......---...--...--....First and third
Jersey cow, 3 years and under 4.................... ....-------------.. First
Jersey heifer, 2 years and under 3-..-..--..-....First and second
Jersey junior yearling heifer--..-....-...-..-.... ------.............Third
Jersey senior champion bull....-...... ........-....------------...--First
Jersey senior champion cow-.........---.... ........-----............First
Jersey grand champion cow......--......-----Grand champion ribbon
Jersey herd----... ---...................--......... ---- -------....... First
Jersey calf herd ................----...............--- -------..... Second
Jersey get of sire-..........------...................-..-.------. Second
Jersey production of cow.............-----------............. Second and third
Holstein junior yearling bull--------.............................-------First
Guernsey senior bull calf .......................------------------..Third
Hereford junior yearling bull..------------.........................Second
Hereford junior yearling heifer............----------....................Third
Angus bull----------..................-.....-........-------------. Second
Steer, special, best 1 year and under 2--...--...-.......First and third
The herd was exhibited at the South Florida Fair, Tampa,
in February, 1923, and the following prizes were won.
Bull, junior yearling.....------ ---........-........... ----..First prize
Heifer, junior yearling ........................------------------.First
Junior champion bull ---.......--........................... -------First
Junior champion cow--..---.......................-----.... ---.. .....First
Grand champion cow---..............Medal and grand champion ribbon
Grand champion bull---......--..Medal and grand champion ribbon
Bull, 2 years and under 3---..........--.........--..............---.. First
Bull calf, 6 months and under 12.......-.........-.......---..........First
Cow, 5 years and over.---...-----......-.........--...-...- ----.. Second
Cow 3 years and under 5---.............................------------Second
Cow 2 years and under 3--------...................... --....... .--. --.. -First
Heifer calf, 6 months and under 12---.......-....-....Second and third
Senior champion cow...............................-----------------First
Grand champion cow-----...........Medal and grand champion ribbon
Aged herd .................................-----------------------..Second
Young herd ...........................----------- --------....... Second
Calf herd ....-....-- ........... ....-........................ Second
Get of sire ......--------...----- ------------------............ Second
Produce of cow -........-.......----........----.........---..---- Third
Four females over 1 year, get of sire -------........................... First
Junior yearling bull.......- ..............-...---------------First
Junior champion bull.............................-------------- ---First


30R Florida Agricultural Experiment Station

Grand champion bull....................-...........Grand champion ribbon
Bull senior calf...................................................................... First
Junior champion bull-... .---------...................---- .---....-- First
Cow, 5 years and over...............--..... .. ..------....---.....--- First
Heifer calf under 6 months-----................ .-----.........----First
Steer under 1 year -----------........................-----... .... First
Champion steer -................. -------------...................-. First
Best purebred steer ...- .......-----------.........................---First

Annual Report, 1923


Wilmon Newell, Director.
SIR: I submit the following report of the Office of Grass and
Forage Crops Investigations for the fiscal year ending June 30,
Assistant Grass and Forage Crops Specialist.

The investigational work of the department has been carried
on in cooperation with the Bureau of Plant Industry of the
United States Department of Agriculture, just as it was last
All of the investigational work is being carried out on the
Station's farm at Gainesville and for convenience in handling the
work it is projected as follows: Experiment Station Project
XIII, Grass and Forage Crop Investigations. The work is then
subdivided into department projects as follows:
(A) Introduction and trial of forage plants.
(B) Plant Breeding.
(C) Fertilizer and rotation experiments with corn, sweet
potatoes, peanuts, and fertilizer tests with Napier grass.
(D) Pasture and lawn grass studies.
Under the foregoing project headings come the various sub-
divisions of each project as it necessarily relates itself to the
main project in question.
During the year about two hundred species of plants were
received from the Bureau of Plant Industry, Department of
Agriculture, Washington, D. C., for trial as forage plants. These
were set in the experimental grass garden in order to study their
possible value as forage crops.
In addition to the vegetative material already mentioned, seed
of many other plants were received from the same source and
planted either in the greenhouse or directly in the experimental
grass garden for study.
The test of bush velvet beans, Mung beans, soybeans and cow-


Florida Agricultural Experiment Station

peas as hay crops revealed the fact that these crops, where
planted on Norfolk sand of poor fertility, give but a light yield
of hay, the cowpea being the best yielder if a wilt and nematode
resistant variety, as Brabham or Iron, is planted.
The test from the standpoint of uniformity was so unsatisfac-
tory that no yield records were taken, but it was clearly evident
that in this test on the class of soil mentioned Brabham cowpeas
for hay outyielded Mung beans, soybeans and bush velvet beans.
In the test of Napier grass as a grazing and silage crop, it was
not possible to do more than start testing the grass as a grazing
crop, owing to the poor arrangement of fields for grazing pur-
In March a field of approximately three-fourths of an acre
adjacent to the University Dairy barn was prepared and set to
Napier grass, the rows being six feet apart and the plants three
feet apart in the rows. The plantings were by root-clump
This field has been divided into two sections, one of which is
being grazed continuously, while the other one is being grazed
intermittently. In addition, a portion of each of these sections
is being cultivated often enough to be kept free of weeds. The
other portions have not been cultivated since the cattle were first
turned in on June 13, 1923, and will not be cultivated any more.
During the period covered by this report two crops'of silage
were cut from a field of Napier grass planted in February, 1922,
for the purpose of obtaining silage yield records. The grass was
planted in six-foot rows using a continuous line of canes. These
cuttings were made in July and November, 1922. Cultivation,
the same as for a corn crop, was given and no fertilizer has been
applied. The average yield of two cuttings from four twelfth-
acre plots was 15.79 tons. The cutting in July averaged for the
four twelfth-acre plots 8.54 tons to the acre while the November
cutting from the same set of plots averaged 7.25 tons to the acre.
The Napier grass from these plots, along with enough from
other fields, was used to fill a 25-ton silo. In tests with other
forms this silage was later fed to dairy cattle by the animal in-
dustrialist who will report this feeding experiment in detail.
From this year's results, in comparing the yields of corn, sorghum
and Napier grass as silage crops, the data indicate that unfer-
tilized Napier grass gave 58 percent better results than the high-
est-yielding, liberally fertilized sorghum tested, and 200. percent


Annual Report, 1923

better than the highest-yielding, liberally fertilized corn tested
for silage purposes.
The test with Napier grass and Japanese cane irrigated and
not irrigated, using overflow from the University septic tanks, is
a joint project carried out in cooperation with the office of public
roads, United States Department of Agriculture.

;:~ ..

Fig. 5.-Napier grass, first cutting, July, 1922.
The yields of the season of 1922 of both irrigated and non-
irrigated Napier grass and Japanese cane are now known. The
Napier grass was cut twice during the year for silage, once in


34R Florida Agricultural Experiment Station

July and again in November, whereas the Japanese cane was cut
for silage only once, this being in November. The photograph
gives some idea of the height and thickness of Napier grass as
cut in July.


Yield to the acre, tons
S Irrigated Not irrigated

Japanese Cane.................................... 29.45 19.02
Napier grass........................................ 28.25 15.79
Difference in favor of Japanese cane.. 1.17 3.23

It is planned to enlarge this experiment by irrigating at least
one one-twelfth-acre plot of Napier grass with city water as a
further check against the sewage water.
In the variety test of millets, Brown Top millet (Panicum
fasciculatum) gave the highest yield of green feed and cured
hay to the acre the first cutting, compared with Pearl millet
(Pennisetum glaucum) and German millet (Setaria italica).
Further data could not be gotten because excessive rains drowned
out the plots.
The results of the test of sorghums, both saccharine and non-
saccharine and Russian sunflower as forage, are shown by the
following figures. As shown by these yield records, the large,
medium-to-late-maturing varieties of saccharine sorghums, like
Texas seeded ribbon cane, Japanese Honey and Orange, can be
expected to give the best results for soiling and silage, whereas
the smaller-stemmed, earlier-maturing varieties, like Early
Amber, make more satisfactory hay plants in combination with
cowpeas. The figures follow:
Acre yield, tons
Variety (Two cuttings)
2541 Darso sorghum........................... . ........... ...7.01
2540 Black amber............... .... ......... .... ......-- ..... 8.03
2544 Honey sorghum........... .............. .. .............. 9.63
2534 Freed sorghum.....--------.....................-. .. .------3.12
2538 Sumac sorghum-....................... ... ....--.......4.481
2532 Dwarf Ashburn.............. ............... ............4.211
2548 Schrock .....................-----..----.---.-- ....7 .26
2552 Dwarf Java........................ ................... .. ........
2549 Orange ................................ .. ................ 7.94
2528 Early Am ber................................................. .............4.30
2525 Japanese Honey Drip................................................. 9.46

Annual Report, 1923


2527 Early Orange....................................................................3.45
2519 Texas seeded ribbon cane..................................................9.55
2521 Red top or sumac................................................................ 6.23
2551 Java ....................................................................................3.21
2535 Feterita .............................................................................2.99
2550 Spur feterita ........................................................................3.86
2522 Feterita- Steckler .......................................................3.21
2543 Pink kafir..........................................................................4.30
2539 Dawn kafir......................................................... ............3.62
2542 Sunrise kafir ..................................................................... 5.06
2545 Black hull kafir...................................................................5.39
2536 Red kafir..............................................................................4.66
2524 W hite kafir..........................................................................5.58
2523 Yellow milo......................................................... ........ 5.52
2531 Dwarf yellow milo.............................................................. 6.09
2547 Manchu brown kaoliang....................................................1.52
2537 W hite kaoliang ................................. ......... ....................1.94
2578 Egyptian wheat...................... ....................
2533 Shallu ......................------ ------................. ----...................... 4.92
2546 Dwarf hegaria................................................. ........... 3.87
2553 Evergreen broom corn........................................................ 2.70
2517 Russian sunflower.............................................................. 4.07
1 First cutting lost.
2 Only one cutting made.
Thru the courtesy of J. H. Beattie of the United States De-
partment of Agriculture, seed of a number of varieties of
peanuts were secured for use in the 1922 variety test of peanuts.
These seed were planted in three-foot rows and the Virginia
bunch, Virginia runner or Jumbo, and the African were planted
12 inches apart in the rows, while all Spanish and Valencias
were planted from 6 to 8 inches apart in the rows. No fertil-
izers were used. The following figures show varieties tested
and yield ,of nuts and hay:
Yield to the acre
Variety Nuts in bushels' Vines in pounds
Virginia bunch (Hawthorne)......12.4 374
Virginia bunch ..............................44.8 986
Jumbo .............................................. 41.7 1190
African ............................................29.5 1020
Valencia ..........................................18.5 850
Improved Spanish ..............-.........29.5 1190
Improved Spanish (S. C.) ..........36.3 1394
Spanish (Madison) ........................19.3 782
Spanish ............................................ 26.1 918
' Virginia Bunch, Jumbo and Valencia figured 22 pounds to the busheL
African and Spanish 30 pounds to the bushel.
Seventeen varieties and strains of velvet beans were included
in the variety test. Quite a variation in the date of maturity,
amount of vine growth, tendency to shatter seed, and yield of
shelled beans was noted.
The bush velvet bean gave the lowest acre yield of shelled

Florida Agricultural Experiment Station

beans (5.4 bushels), while an early-maturing, medium-vining
variety received from Biloxi, Miss., several years ago under the
name of "Tiger," gave the highest acre yield of shelled beans
(25.4 bushels).
To the 1923 velvet bean variety test has been added two new
strains received from the Bureau of Plant Industry; namely,
Early Arlington and Tracy's Early Black.
Thru the courtesy of the Office of Cereal Investigations of
the Federal Bureau of Plant Industry, a small quantity of the
planting material of 28 varieties, strains and selections of oats
were secured. In addition to these, five strains were bought of
seed dealers. All were planted in November. No yield records
were taken but from time to time observation notes were made;
similar plantings will be made on a larger scale this fall. The
question of yield of oats, either for winter grazing, hay or grain,
hinges largely on the ability of the oat to resist rust. Some of
the varieties in the test possessed rust resistance to a consid-
erable degree as the accompanying illustration shows.
Strains standing out prominently as rust-resistant were Red
Rustproof (selection) C. I. No. 518-5, Algerian C. I. No. 1571,
Red Rustproof (Hastings) C. I. No. 884, (Ferguson), Red
Rustproof C. I. No. 844 and Red Rustproof C. I. No. 1815.
Since disease resistance is such a factor in this study of
high-yielding strains of oats, it is deemed best to carry all fu-
ture work with oat varieties along in cooperation with the De-
partment of Plant Pathology. Seed were saved of the rust-re-
sistant strains mentioned.

The breeding work with Spanish peanuts continues to give
gratifying results. The 20 high-yielding selections mentioned
in the 1922 annual report on an average outyielded the check
plots planted to a high-yielding strain of Spanish peanuts devel-
oped by the United States Department of Agriculture at its
plant breeding stations at Florence, S. C. Several of the selec-
tions outyielded the checks by several bushels.
Last fall 500 plant selections were made in a field of Spanish
peanuts growing on the Experiment Station farm, and .from
this number 100 of the highest-yielding selections have been
planted in separate rows for further study.


Fig. 6.-Rust-resistant strains of oats show up prominently here

Florida Agricultural Experiment Station

The Merker and Napier grass improvement work has brought
out the fact that there is a great difference in the yielding power
on individual plants grown from seed. The yield of green forage
of individual plants from the seedling nursery ranged from half
a pound to 46 pounds. Increased plantings propagated by
single-eye cuttings, clonal division and bagged and unbagged
seed will be made this fall for further study.
The most striking thing brought out in this work so far is
the fact that where Spanish peanuts have been grown in rotation
with corn and velvet beans for five years and the peanuts var-
iously fertilized and then half of each plot treated with a ton of
ground limestone to the acre, the five-year average shows con-
clusively that lime has decreased the yield of nuts and hay.
In the case of the check plots the same is true. Figure 7 shows
limed and unlimed parts of the field.

Fig. 7.-Showing limed and unlimed portions of a peanut-fertilizer experi-
ment; limed area is in foreground.
This test is in the nature 'of a rotation experiment, sweet
potatoes being fertilized one year with acid phosphate, soft
and hard phosphate, dried blood and potash, singly and in
combination, and the next year followed by a peanut crop to get
the residual effect of the fertilizer on the peanut crop. Results
to date indicate that nitrogen and potash are limiting elements
in the production of a profitable crop of sweet potatoes on Nor-
folk sand of from poor to medium productive power. Best re-
sults have been secured from the use of a complete fertilizer.


Annual Report, 1923

In the case of the residual effect of the fertilizer on the yield
of peanuts, none of the fertilizer treatments showed any marked
This work, as outlined in the last annual report, has been
pursued with some enlargements, both as to pasture and lawn
Additions to the 11 pasture grasses that.were set last year
were made this year. These new plants are: Vasey grass
(Paspalum larranagai) (Panicum repens), Para grass (Pani-
cum barbinode), Napier grass (Pennisetum purpureum) and
Maiden cane (Panicum hemitomon). The grasses set last year
are: Carpet grass (Axonopus compressus), Giant Carpet grass
(Axonopus furcatus), Bermuda grass (Capriola dactylon), Giant
Bermuda grass (Capriola dactylon var. maritimus), St. Lucie
grass (Capriola dactylon var. St. Lucie), Bahia grass (Paspa-
lum notatum), Dallis grass (Paspalum dilatatum), St. Augus-
tine grass (Stenotaphrum secundatum), Golden Plume grass
(Chrysopogon monticola), Blue Couch grass (Digitaria didac-
tyla), and Centipede grass (Eremochloa ophiuroides).
All of both years' plantings have been grazed constantly and
closely observed at regular intervals to determine their value
as permanent pasture plants. So far, of the newer grasses in
the' lot Bahia, Dallis, Carpet, Vasey and Centipede are promis-
In March of this year an experiment was started which has
for its object the determining of the best time, rate of seeding
and method of planting of five of the most important permanent
pasture plants; namely, Carpet grass (Axonopus compressus),
Dallis grass (Paspalum dilatatum), Bermuda grass (Capriola
dactylon), Bahia grass (Paspalum notatum), and Japan clover
or Lespedeza (Lespedeza striata).
Each grass is being seeded with lespedeza and one plot is
being seeded to a mixture of all the grasses and lespedeza. The
plots are one-one-hundred-seventy-fifth (1-175) of an acre each
in size, each plot is being run in triplicate and seedings are
being made every month. It is planned to run this experiment
long enough to give accurate data on the time, rate and method
of planting.
Plans are being made for further enlarging the pasture inves-


Florida Agricultural Experiment Station

tigations by clearing additional land and planting out at least
five of the most important permanent pasture plants. This will
be done on an area of sufficient size to get data on the cost of
producing permanent pastures, the carrying capacity of the
various grasses and some information as to the fertilizing and
management of pastures.
The planting of Molasses grass (Melinis minutiflora) S. P. I.
54448 was about completely killed out on the lower lands by a
temperature of 25 F., whereas plantings on the higher lands
with better air drainage withstood the cold, being killed to the
ground but coming back in the spring.
Jaragua grass (Andropogen rufus) S. P. I. 54679 was prac-
tically killed out last winter by a temperature of 25 F. even
on the higher lands. The only plots which survived were the
ones which had a full season's growth standing when the freeze
came. These were killed to the ground but, owing to the pro-
tection offered by the heavy growth, the basal buds were not
killed, and a good crop was made this spring on which cattle
have grazed freely.
Dallis grass (Paspalum dilatatum) and Vasey grass (paspa-
lum larranagai) continue to look promising as wet heavy land
pasture grasses, and especially so since they withstood success-
fully the temperature of 250 F. of February 19 and continued to
furnish some grazing all thru the winter.
During the year a total of approximately five acres has been
seeded to Bahia grass, using Florida, Cuba and Costa Rica seed.
On an average the Costa Rican and Cuban seed gave better
germination than the Florida seed. Better germination was
gotten during June, July and August than from either spring
or fall seedings. On the average, seed sowed on prepared land
germinated better than seed sowed on unprepared land. And
seed lightly covered germinated better than seed not covered,
both on prepared land and unprepared land, with one exception.
The original planting of Bahia grass in the pasture among a
Bermuda grass sod is now nine years old. It consisted at first
of two rows 100 feet long and 3 feet apart. It was fenced for six
months after the grass was first set. Then the fence was removed
and cattle have grazed it continuously ever since. The sodded
area is now 150 feet long by 25 feet wide and is crowding the
Bermuda grass back on all sides.
Owing to the thick scaly root stalks and dense, deep, fibrous


Annual Report, 1923

root system of Bahia grass it seems well adapted to a variety
of soils.
A portion of the Bahia grass was burned off this spring with
no apparent bad effects even where some of the grass had a whole
season's dead growth on it. This practice is not to be recom-
mended, however.

Fig. 8.-Bahia grass (right) crowding out Bermuda.


The lawn grass plots set out last year were closely observed
during the year. St. Augustine grass (Stenotaphrum secunda-
tunm), Centipede grass (Eremochloa ophiuroides), St. Lucie
grass (Capriola dactylon, var. St. Lucie), and Bermuda (Capriola
dactylon) gave most satisfactory results as lawn grasses.- Accord-
ing to the results so far these grasses should take rank in the
order named.
Ordinary Carpet grass has sodded over rather slowly, but
once sodded it appears to make a satisfactory lawn.
Last fall (1922) Italian rye grass (Lolium italicum), Red top
(Agrostis alba) and White clover (Trifolium repens) were


Florida Agricultural Experiment Station

sowed across a section of each of the 11 lawn grass plots. A study
was made this spring and summer of the effect of the growing
of these plants on the spring and early summer growth of the
lawn grasses as originally set out. All of these fall-sown grasses
grew well during the fall, winter and early spring, affording
green lawns in the winter when some of the southern grasses
were browned by frost. All had a tendency to retard the spring
growth of the southern grasses, this tendency being less pro-
nounced with St. Augustine, Centipede, the Bermudas and
Bahia grasses than with some of the others.

Fig. 9.-Bahia grass. Note the thick, short-jointed surface runners and
dense, deep, fibrous root system.
This work has been enlarged by the addition of Dallis grass
(Paspalum dilatatum), Lovy Lovy grass (Andropogon acicu-
latus), three species of Osterdamia or Zoysia, a grass known as
Japanese or Korean lawn grass, one known as Manila grass, one


Annual Report, 1923

known as Mascarene grass, and a plant of the Vervain family,
Lippia repens, which is notably drought-resistant and is used for
lawn and street park plantings in the west, particularly in
Some plots on the University campus have been disced thoroly
and seeded to Carpet grass, Dallis grass, Bahia grass and les-
pedeza, respectively and in combination. These seedings were
at rates heavier than commonly recommended for pasture pur-
poses but otherwise they serve also as pasture grass experiments.

Fig. 10.-General view of lawn-grass experimental plots, Florida Experi-
ment Station, 1922.

Three and a half acres were set to rooted kudzu plants in
January, 1922. The plants were set in rows six feet apart, and
the plants every four feet apart in the rows. Corn was planted
in the middles of the kudzu rows and cultivated up to about June
1, thereby keeping the kudzu worked. If kudzu will grow suc-
cessfully on Norfolk sand of medium productive power, it will
be used for hay and pasture experiments.
Hubam clover (Melilotus alba var.) gave good results again
this year when inoculated and planted in November on the
heavier types of soil, but again gave unsatisfactory results on


Florida Agricultural Experiment Station

high pine land, even where inoculated and when the land was
treated with lime and phosphate. This clover apparently re-
seeds itself satisfactorily. Sour clover or annual yellow Sweet
clover (Melilotus indica) was unsatisfactory on all soils, its
growth being not nearly as good as that of Hubam, clover.
Subterranean clover (Trifolium subterraneum) S. P. I. 55707,
a native of Asia and a plant that sets its seed under ground as
.-peanuts, was planted again this year and, as last year, it gave
promising results on the heavier more moist soils, but was
unsatisfactory on high pine land. It is susceptible to root-knot
and to a root disease known as rhizoctonia.
Serradella, a legume that holds some promise as a sandy land
winter cover and green manure crop and forage plant, was tried
this year for the first time. Trouble was experienced in getting
the plants thoroly inoculated. On the whole the growth made
was not satisfactory, tho where the best growth was obtained
the plants were better inoculated than where the poorest growth
was made, which indicates that once the ground is thoroly inocu-
lated the plant may be valuable.
Two species of Crotalaria that have been under observation
several seasons have shown their ability to make good growth
on high pine land. The plants are erect growers, making a
growth 3 to 7 feet tall, are fairly leafy, have yellow blossoms, and
form seed pods similar to the ordinary rattle-box to which they
are closely related. The roots are abundantly supplied with
nodules, indicating good nitrogen gatherers. Bees have been
observed working this plant for nectar. Cattle do not eat these
Crotalarias readily either in the green or dry stage. Crotalaria
looks promising as a cover and green manure crop.
The chemical analyses, growth and habits of the Crotalarias
indicate a cover and green manure crop of possible value.


s 'B

Crotalaria usaramoensis ............ 9.15 4.73 4.02 21.38 41.87 18.85
Crotalaria sericea ...................... 9.70 6.40 3.48 15.00 49.62 15.80
(Note-Plants about two feet high when cut for analysis.)


Annual Report, 1923

Figure 11 gives some idea of the most promising species of
Crotalaria under observation.
Considerable time has been spent in replying to inquiries
relative to pasture and forage crops. Planting material of new
forage plants was distributed upon request to numerous farmers
in nearly every county in the state and at the suggestion of the
animal industrialist several county agents were supplied with
enough material for putting on pasture demonstrations with
one or two farmers in their counties.

Fig. 11.-Crotalaria usaramoensis S. P. I. No. 51841, planted March 24,
photographed August 11; plants 5 feet high and in full bloom.

A large number of specimens of grasses and other plants were
received and identified.
The helpful advice and suggestions of the animal industrialist,
together with his willingness to cooperate in the matter of labor
and teams under his control, rendered the enlargement of the
work possible.



Florida Agricultural Experiment Station


Wilmon Newell, Director.
SIR: I submit the following report of the Department of
Chemistry for the fiscal year ending June 30, 1923.

The work of the department during the year was devoted to
citrus problems, sugar cane, pecan and soft-pork investigations.

The work on this project was carried on along the same lines
as outlined in the last annual report. The experimental grove at
Lake Alfred has made good growth and will bear its first crop
next season. A light case of dieback developed on the check
plot, apparently due to over-fertilization as the entire grove
showed indications of over-feeding. The amount of ammonia,
accordingly, was reduced materially in the fall application of
fertilizer and all signs of dieback have disappeared. An analysis
of soil from the dieback-affected trees, compared with an analysis
of soil from normal trees, showed no differences which would
indicate the cause of the disease.
The trees at Gainesville, with one exception, have made a
normal growth and borne a good crop of fruit. The tree in
tank number 4 is in an unhealthy condition but shows no symp-
toms of dieback nor could the plant pathologist find any evi-
dences of disease. It may be that the tree is root-bound, as the
tanks are rather small for trees of its age.
Table 5 gives the results of last year's study of the drainage
water from the eight soil tanks. A total of six samples were
collected during the year. A study of this table reveals several
interesting points. It will be noted that the amount of drainage
collected from the various tanks varies greatly. This is partly
explained by the differences in the sizes of the trees growing in
the tanks. Tank 5, which had the largest amount of drainage,
contains the smallest tree. The larger trees with branches
hanging over the outer rim of the tank caused considerable rain-
fall to be shed outside the tank. Furthermore, the larger trees
used more water, hence left the soil drier than the smaller one.





Total drainage in liters ........ 961.74
Total solids in grams.......... 3,957.61
Non-volatile solids................ 2,980.65
Ammonia ............................. 99.46
Nitrites .................................. .18
Nitrates ............................... 563.67
Phosphoric acid ................. 9.14
Sulphur trioxide ............. 1,987.00
Chlorine ............................. 38.70
Calcium oxide ....................... 638.66
Sodium oxide .................... 34.77
Potassium oxide .................. 277.55
Aluminum oxide .................. 327.69
Ferric oxide .......................... .45






Cd 0





o C

749.65 502.15 336.73
1,850.33 1,390.85 293.59
1,256.35 944.15 204.67
34.14 .24 .08
.18 .10 .03
467.37 467.21 58.86
.61 .40 .28
631.89 382.51 88.03
37.38 42.58 19.21
186.10 179.81 29.08
45.69 65.22 18.00
240.39 257.04 46.78
116.79 5.14 3.44
.14 .06 .04

Florida Agricultural Experiment Station

Despite the differences in the sizes of the trees, it should be noted
that the trees receiving ammonia from manure, which adds con-
siderable organic matter to the soil, had the smallest amount of
drainage. A study of the total solids and fixed solids removed
shows that the mineral sources of ammonia cause a larger amount
of salts to be removed from the soil than do the organic sources.
The sulphate of ammonia causes increased loss of calcium or
lime and potash, as well as aluminum, while the nitrates caused
increased loss of sulphates. The manure exerted a strong pro-
tective action on all of the soluble soil salts, as is shown by the
small amount of fixed solids removed from these two tanks.
While the above results cannot be taken as final conclusions they
should show every farmer the benefit to be derived from increased
amounts of humus or organic matter in the soil in retaining
soil fertility.
The study of the effect of copper sulphate on nitrification and
ammonification in soils was further studied with negative re-
sults. No stimulation of either nitrification or ammonification
was found.
Further tank studies were begun during the year, using
galvanized iron tanks two feet in diameter and three feet deep,
equipped with outlets at the bottom to collect drainage. Ten such
tanks were filled with soil in which budded citrus trees were
planted. Two tanks were then fertilized with a complete fer-
tilizer containing a double quantity of ammonia from blood, two
with a double amount of phosphoric acid from superphosphate,
two with a triple amount of potash from sulphate of potash,
while two were given a normal fertilization. The object is to
determine whether over-fertilization with any of the three fer-
tilizer constituents will bring on dieback. All the trees made a
normal growth and were in a healthy condition at the close of the
year. Ten more tanks have been purchased and it is planned to
extend the study of the action of bluestone in the soil and the
citrus tree. Samples of soil from the experimental grove at Lake
Alfred were analyzed to determine whether any changes had
taken place due to the difference in fertilizer treatment. How-
ever, no differences of note were found.
The experiment on the effect of high versus low potash fertili-
zation had to be curtailed because the owners of the grove at
Agricola decided not to continue their cooperation. This left only


Annual Report, 1923

the grove at the Citrus Experiment Station in the experiment.
Fruit from both the Agricola and the Station groves were
analyzed. Three samples of grapefruit and two of oranges,
collected at different times from the Station grove, and one
sample from the Agricola grove were analyzed. The experiment
has not run long enough to warrant any conclusions.
The study of the availability of various forms of. phosphoric
acid for citrus trees was continued (see 1918 Annual Report, p.
39R, and 1922 Annual Report for description of experiment).
A report of five years' results was presented before the Florida
State Horticultural Society in Orlando and is here summarized.
1919 | 1920 1 1921 1922 1923 | Av. 5 Yrs.
Acid phosphate.... 12. 33.3 75 266 154 108
Steamed bone........ 4.6 33.3 42 307 159 109
Soft phosphate...... 7.1 33.3 82 267 65 91
Pebble phosphate 12.9 22.2 78 214 98 85
Commercial ....... 8.1 28.9 37 295 101 94

Table 6 gives the yields for each of the last five years with
the five-year average of the grapefruit trees in the older grove.
The young grove has only borne two crops, so was not tabulated.
The oranges in the old grove are on sour stock and have only borne
three crops. Due to a misunderstanding it was possible to obtain
weights on only two of these crops, both of which were light.
A study of Table 6 shows no marked difference due to the
various forms of phosphoric acid. No one source of phosphoric
acid has uniformly given better yields than another. One draw-
back to the experiment mentioned above is the absence of a no-
phosphate plot. It may be that the soil contains a sufficient
amount of this element for maximum development of the citrus
trees. Owing to the fact that the grove was 'privately owned,
it was not possible to include a no-phosphate plot in the experi-
ment, as it might have caused a stunting of the trees which
would have caused the owner to discontinue the experiment.
The only conclusion warranted by these yields is, it is believed,
that no one source of phosphoric acid will give a higher yield or a
better quality of grapefruit.
Future weights of oranges may show a difference due to the
different sources of phosphoric acid, as the orange trees are the
only ones which have at any time shown any differences in ap-
pearance. Last spring the trees on the bone plots seemed to have
a slightly deeper-colored foliage than the other trees.


Florida Agricultural Experiment Station

A new citrus experiment was begun in March with satsuma
oranges at Round Lake, in Jackson County, in cooperation with
the Dekle Land Company. The object of the experiment is to
determine the best method of fertilizing the satsumas, both as
to time of application and composition of the fertilizer.
The sugar cane investigations have continued to meet with
misfortune. The experiment on the east shore of Lake Okee-
chobee was twice flooded out, due to high water. With the
improved drainage facilities, similar floods in the future should
not occur, and it is planned to start the experiment again this
The experiment at Gainesville with Japanese cane was planted
on more suitable ground and is making good growth.
The pecan experiments in cooperation with the Bureau of
Plant Industry, United States Department of Agriculture, were
continued. A crop of nuts was harvested from the grove at
Baldwin but showed no differences due to the fertilizers used.
The grove at Jacksonville will probably bear a light crop this
The chemical side of the soft-pork investigations, directed by
the animal industrialist, were carried out along the same lines
as previously. The results obtained will be found in the report
of the animal industrialist.
A new project was begun to study the mineral content of
Florida-grown cattle feeds in order to determine whether or not
these feeds contain sufficient minerals for normal growth and
development of livestock. About thirty samples of grasses were
analyzed, together with some grains.
A tobacco experiment was also begun at the Tobacco Experi-
ment Station at Quincy. The objects of the experiment are
three-fold: First, to determine the best source of phosphoric
acid for shade-grown wrapper tobacco. In this experiment
superphosphate, basic slag, steamed bone, precipitated bone and
non-acid phosphates are used as sources of phosphoric acid.
Second, to determine whether sulphate of potash or carbonate of


Annual Report, 1923

potash is the best source of potash. Both materials are being
used in two different amounts. Third, to determine if it is pos-
sible to raise tobacco without the use of stable manure.
In order to test out various new fertilizers that appear on the
market from time to time a series of ten plots of a thousandth
(1-1000) acre each were constructed with a four-inch concrete
wall three and a half feet deep, dividing the plots to prevent any
leaching of fertilizers from neighboring plots. These were com-
pleted at the close of the fiscal year. Due to the disturbed condi-
tion of the soil no tests were begun but all of the plots were
planted to cowpeas. These will be plowed under this fall and a
test begun.
In addition to the work of the above problems, samples of
peanuts, grasses and forage crops were analyzed for the forage
crop specialist in connection with experiments in that depart-
The usual number of rocks and miscellaneous materials were
tested qualitatively for persons thruout the state.
The successful carrying on of the work on the various problems
of the department was due in a large measure to the hearty co-
operation of Assistant Chemists C. E. Bell and J. M. Coleman.


Florida Agricultural Experiment Station


Wilmon Newell, Director.
SIR: I submit the following report of the plant pathologist for
the fiscal year ending June 30, 1923.
Plant Pathologist.

On July 1, 1922, G. F. Weber began his work as assistant plant
C. T. Link, a State Plant Board employee, was detailed to this
laboratory to assist in citrus canker investigations. Mr. Link
assumed his duties on Jan. 1, 1923.
During the year several new books were added to the depart-
ment's library. Some periodicals were bound. Subscriptions to
certain publications, which were discontinued during the war,
were renewed.
The correspondence concerning plant diseases was rather
heavy during the year, especially concerning citrus and truck
Two bulletins were published by this department: Bulletin
166, "Tobacco Diseases in Gadsden County in 1922," by W. B.
Tisdale, and Bulletin 167, "Preliminary Report on Controlling
Melanose," by O. F. Burger, E. F. DeBusk and W. R. Briggs.
There were also two press bulletins published: Press Bulletin
342, "Green Spotting of Citrus Fruit," by O. F. Burger and
E. F. DeBusk, and Press Bulletin 343, "Black Rot of Oranges,"
by O. F. Burger and Wm. Gomme.
Two papers were read by 0. F. Burger at the American Phy-
topathological Society, which met at Boston, on melanose and
citrus canker. A paper was also read at the Florida Horticul-
tural Society on the "Control of Melanose." Assistance was
given to the Agricultural Extension Division by holding meet-
ings in various counties discussing citrus diseases and their
The work on melanose control was pushed forward during
the year. This work was greatly facilitated by County Agents
E. F. DeBusk and W. R. Briggs, who assisted in the spraying


Annual Report, 1923

Eleven experiments were conducted in which 3-3-50 bordeaux
mixture plus 1 percent of oil emulsion was used for the control
of melanose. Eight experiments were in Lake, two in Manatee,
and one in Brevard Counties. Approximately, 1,255 acres were
under experimentation. The largest single acreage was in
Manatee County, where approximately fifteen thousand trees
were sprayed.


Kind of

Oranges .........
Oranges ..........
Oranges ..........
Oranges ..........
Oranges ..........
Grapefruit ....
Grapefruit ...
Grapefruit ....
Grapefruit ....
Grapefruit ....
Grapefruit ....
Grapefruit ....

Sprayed with Bordeaux
CL> C) C
Number of Time
grove and of C 8
county Spraying U .

1. Lake ...... Mar. 27... 61.1 26.9 12.0
2. Lake ...... Mar. 24.... 80.0 17.0 3.0
3. Broward Mar. 21.... 37.0 60.0 3.0
4. Lake ..... Apr. 9.... 88.0 10.0 2.0
Average ...-... 66.5 28.5 5.0
5. Lake ...... Mar. 28.... 63.4 26.9 9.7
6. Lake ..... Mar. 29.... 63.0 30.0 7.0
7. Lake ...... Apr. 26.... 84.0' 13.0 3.0
8. Lake ...... May 5.... 82.0 15.0 3.0
9. Manatee May 12.... 50.0 38.0 12.0
10. Lake ...... 76.0 21.0 3.0
Average ...... 69.0 24.0 7.0

Not Sprayed with Bordeaux

Kind of Number of Time r m
grove and of 8 .8 S t
Fruit county Spraying 4

Oranges ...----. 1. Lake ...... Mar. 27... 13.9 30.0 56.1
Oranges .-----.... 2. Lake...... Mar. 24 43.6 23.3 33.1
Oranges .......... 3. Broward Mar. 21.- 0.0 45.0 55.0
Oranges ------- 4. Lake ...... Apr. 9.... 43.6 23.3 33.1
Oranges .......... Average ...... | 25.5 30.4 44.1
Grapefruit 5. Lake ...... Mar. 28-... 33.5 32.5 34.0
Grapefruit ...I 6. Lake ...... Mar. 29.-- 18.0 23.0 59.0
Grapefruit .... 7. Lake ...... Apr. 26.... 36.0 45.0 19.0
Grapefruit 8. Lake ...... May 5- 33.5 32.5 34.0
Grapefruit 9. Manatee May 12.... 9.0 33.0 58.0
Grapefruit 10. Lake ...... 19.0 34.0 47.0
Grapefruit .... Average ... 24.6 33.3 42.1

The data were gathered in two ways. In most of the groves
the fruit on the trees was counted and classified as brights,


54R Florida Agricultural Experiment Station

golden and russets. In the largest experiment the fruit was
classified in the packing house. In the field, only those fruits
were counted which could be reached easily and inspected from
the ground.
All growers know that melanose is worse at the base of a tree
than at the top. This is because there is generally less dead wood
near the top of the tree than lower down. In all experimental
groves oil spray was used in 1921 for scale and whitefly; and
in 1922, sometime between July and September, depending upon
the need of the grove and the convenience of the grower, another
spraying was made for the same purpose. Rust mites also were
kept in check by either the lime-sulphur spray or sulphur dust. In
all the experiments the check plots were treated in the same
manner as the plots sprayed with bordeaux-oil. All groves were
pruned, that is, as much.of the dead wood was pruned out as was
commercially practical. As stated previously, only groves badly
affected with melanose were selected, but in these the growers
were doing all they could to produce bright fruit.
In Experiment 1, carried out in 1921, the cost of spraying
was 13 cents a tree. That was an ordinary grove. In Experi-
ment 9, running water was secured in the grove and the item of
hauling eliminated, the cost was reduced to 8 cents a tree. Cost
figures are given below for spraying a grove of 15,000 trees.
Labor ................. ................... ........................................$436
Lime ..................................... ...................... 85
Bluestone ................... ..... .. .................................. 160
Oil em ulsion .................................... ....................................... 442
Overhead ................................................................................. .... 100
T total ........................................... ................................ $1,223
Cost to the tree ....... .....................................$ .0816
Cost to the box ...................................... .016
This was a grapefruit grove and the trees averaged five boxes
each. This grove was so large it took approximately thirty
working days to spray it.

The major part of the Pathologist's time during the year
was devoted to the study of citrus canker.
Inoculation experiments necessitated the purchase of a suit-
able greenhouse. This greenhouse is 171/2 feet wide and 40 feet
long. A place was excavated so that cages 10 feet high could
be placed on the inside. The cages are 8 feet long, 7 feet wide,
and 10 feet high. They are placed firmly on a concrete base,

Annual Report, 1923

around the inside and outside of this base are small moats.
These moats are kept filled with water so that no crawling in-
sects can enter. The cages are made of copper wire, 24 meshes
to the inch. The entire greenhouse is ventilated from the inside.
It is equipped with a hot water system for heating in winter.
Surrounding the greenhouse is a strong, eight-foot, cyclone fence.
The major portion of the time has been devoted to the study
of the life history of the organism and the conditions under
which it remains viable and causes citrus canker.
It was found that potato agar is one of the best media for the
growth of the organism. It has been living more than a year
on this medium.
Wet pine shavings were sterilized and inoculated. The or-
ganism reproduced and lived on this wood for several months.
When citrus seedlings were inoculated with organisms from
one of these cultures they became infected. The organism lived
on sterilized filter paper for several months. Sterilized tap water
was a good medium for its growth. Unsterilized muck soil was
unfavorable for the development of the organism. Pots of soil
were inoculated with cultures of the organism and grapefruit
seed planted; when the seed sprouted the young plants were
free from the disease.
Sterilized muck soil was treated in the same manner and no
infection was obtained on the young seedlings.
Shavings were cut from a citrus limb, put in test tubes with
some distilled water and sterilized. The shavings were inocu-
lated but the organism soon died on this medium.
During the fall and winter inoculations made on young citrus
leaves, by brushing the organism onto the leaf with a camel's
hair brush, did not show infections for 30 days. If the leaf was
wounded the infection showed up in from seven to ten days.
During the summer, however, the inoculations produced infec-
tions much quicker. The upper and lower surfaces of young
leaves were painted with water suspension of the bacterium.
Those leaves painted on the lower side developed more spots of
infection than those leaves painted on the upper side.
In no case has the organism been found to lose its virility on
potato medium. The organism in old cultures infect as readily
as do the freshly isolated organisms.
Black rot is a disease caused by a fungus known as
(Alternaria citri Pierce). This fungus was first described by


Florida Agricultural Experiment Station

N. B. Pierce in 1902 on California Navel oranges. Later this
was described as causing a dropping of fruit in Arizona.
At the blossom end of citrus fruit there is a small opening
which gives a ready entrance to the fungus. Weather condi-
tions also influence this disease. Since so much of the disease
was present this year, it might be assumed that last summer
was favorable for the development of black rot.
DISTRIBUTION: Letters and specimens have been received
from all areas of the state, complaining of this disease, which
this year was general. Each year there has been a small amount
of the disease present, 'but so little that the grower has not
noticed its existence. For some unexplained reason this disease
makes its appearance and causes considerable damage at
different times. In 1911 H. S. Fawcett recorded black rot as
doing considerable damage. Since then the disease has caused
no alarm until this season.
It was formerly thought that the Navel orange was the only
variety attacked. In 1911 it was found on Pineapple and Ruby
Blood. This year (1922-23) it has been reported as occurring
on Ruby Blood, Parson Brown, Pineapple, Jaffa, Tangerine, and
Valencia. These investigations were made during the middle
of November, 1922. The infection varied from 5 to 25 percent.
One grove of Jaffa oranges was visited where a drop of 25 per-
cent of the fruit was caused by black rot. A considerable
number of oranges, no doubt, go thru the packing houses with-
out the disease's appearance until thb fruit arrives on the
In the fall of 1922 the plant pathologist's attention was called
to the fact that many of the early oranges were not coloring up
properly in the coloring rooms. This complaint had become so
general over the state that it became necessary to determine
the cause.
Two lots of fruit were used in. experiments for this purpose.
The first lot was "commercially" picked and the second lot
carefully picked. Twelve individual fruits from each lot were
treated in the following manner:
Experiment 1: Twenty-four fruits were bruised with the
blunt end of a lead pencil so as to break the oil sacs.
Experiment 2: Some of the green oranges were peeled and
the oil squeezed out of the peel and dropped onto 24 oranges.


Annual Report, 1923

Experiment 3: Oil of lemon was bought at the drug store
and dropped on to 24 oranges.
Experiment 4: Twenty-four oranges were used as a check.
They were not treated in any manner.
All the oranges were placed in the coloring room of a com-
mercial packing house, with a carload of fruit which was being
colored. They were left in the room for 36 hours. At the end
of this time they were taken out and examined.
It was found that in Experiment 1, where the fruit was
bruised, the area so injured did not turn yellow but was of a
brownish-green color. In Experiment 2, where oil was squeezed
out of a green rind and placed on the fruit, the area so treated
remained green. In Experiment 3, where the oil of lemon was
dropped on the oranges, the treated area was of a brownish-
green color. Those used as a check-Experiment 4-were not
spotted but were colored uniformly.
Some of the oranges from the commercial picking had a few
spots other than where they were treated. The carefully picked
and handled oranges-when untreated-had no spots.
The above experiments, therefore, show that it is the liberated
oil which causes this peculiar spotting.
There has been considerable complaint that the oranges with
these spots, decayed on the way to market. It has been shown
repeatedly that an injured orange is potentially a decayed
orange. Injuries, such as clipper cuts and bruises, break the
rind and make an opening for the blue mold fungus. This
fungus cannot penetrate an unbroken rind.
An orange picked in the fall is tender and its rind is easily
injured; hence, much decay may be expected at this season.
Spraying experiments were continued to control citrus scab
in the nursery. These results will be reported in detail later
in the form of a bulletin.
An experiment was carried on to see if the scab organism is
carried on the seed. Sour oranges which were badly affected
with scab were taken and the seed removed. Also sour oranges
were taken which had no scab..iofection and the seed were
removed. : '.: '
These seed were planted in a seedbed half a'.mile from any cit-
rus trees and separated'froi:i.tlhe neaie~i'.sour orange by native
woods. Both .lots -of seed Nver 'planted in alter*iate rows and
no scab showed [p. .: ; -.* .
' "':'* ''.*


Florida Agricultural Experiment Station

As a check, however, sour orange and grapefruit seed were
planted near the sour orange trees and they became badly
scabbed. It is believed that scab is blown by wind from near-by
infected trees rather than carried by the seed.
The experiment begun by C. D. Sherbakoff in 1919 to control
pineapple wilt was carried on during the year. It was shown
that slips selected from healthy plants give best results. Such
plants grew larger, were healthier and produced better fruit.
This spring, however, the disease began to show up in those
plants. The experiments must be discontinued on account of a
lack of funds.
Tobacco diseases and their control are reported on by W. B.
Tisdale, assistant plant pathologist, (see page 128R) in con-
nection with his report on the work of the Tobacco Experiment
Station at Quincy.

The work of the Department concerning the investigations
and control of the diseases of truck crops is reported below by
G. F. Weber, assistant plant pathologist.
From a third to a half of the time of the assistant plant
pathologist was spent culturing and identifying various organ-
isms which cause plant disease. These diseased specimens were
received from growers from all parts of the state and on a large
number of different hosts. He also acted in this capacity for the
nursery and quarantine inspectors of the State Plant Board.
Approximately 1,000 identifications of organisms causing dis-
eases of plants were made. A heavy correspondence was carried
on, answering inquiries concerning the prevention and control
of plant diseases.
About a month was devoted to answering emergency calls of
the Agricultural Extension Division.
A plant disease survey, wae.made of the. tomato and Irish po-
tato areas of the state.: :. -. \ .* '
A paper entitledl"MVosaic Disease of Sweet Potatoes" was sent
to the phytopathological sectioin:f 'fh6. American Association
for the Adda'ncement of Scieint' Wvhich '.mne during the year
in Boston. "'.' : : '


Annual Report, 1923

A series of experiments were conducted, the object of which
was to determine the amount of reduction in germination result-
ing from the pre-soak treatment, in which nine different kinds
of seed; namely, beet, cabbage, cucumber, eggplant, okra, water-
melon, squash, beans and cantaloupe, were treated with corro-
sive-sublimate solution (strength 1:1000). This disinfectant
was used because the poison is easy to handle and the time of
disinfection is relatively short. Tap water was used in making
up the disinfectant and in every case the seed were planted in
seed beds out of doors. They were watered well but were not
shaded. The percentage of germination was calculated direct
since 100 seed were planted in each row; the percentage of seed-
lings coming up were determined and designated as percentage.
The counts were made usually from 10 to 14 days after planting.
The seed were soaked in water for ten minutes then placed on
wet filter paper in a moist chamber for different periods of
time up to eight hours. They were then soaked in corrosive
sublimate for ten minutes, then placed on filter papers wet with
this disinfectant in moist chambers for an hour. They were then
The results are as fallows: All seed except those of eggplant
that were soaked from one to three hours in water before disin-
fection showed from 1 to 5 percent increase in germination over
the dry checks. After three hours of soaking the germination
gradually dropped, those soaked eight hours showing from 20 to
25 percent decrease in germination. When considering the extra
amount of time and labor required to treat seed by this method
and the small increase gained in germination, it was concluded
unadvisable to recommend such treatment.

A disease of sweet potatoes was observed in a ten-acre field
on the campus of the University of Florida. The actual number of
diseased and healthy plants in every row was counted and re-
vealed the fact that six percent of the plants were diseased. Close
examinations showed symptoms similar to mosaic diseases com-
mon on other plants. The internodes of the runners were de-
cidedly shortened, thus the nodes from which the leaves devel-
oped were closer together than in normal plants, giving the
diseased plants a decided rosette appearance. The petioles were


Florida Agricultural Experiment Station

somewhat shorter and thicker than those of normal plants. The
petiole was often flattened at the point of union with the blade.
The larger veins branched out from the petiole into the blade in
an abnormal manner, suggesting fasciation; they appeared
much wider and more prominent than the veins in normal leaves.
The tissue between the veins was of a uniform green color,
decidedly raised or sunken, forming pouch-like areas. There
was no mottling in the sense that leaves of cucumber and tobacco
plants are mottled when affected with mosaic. The blades were
crinkled along the edges, curling backward and in severe cases
On August 31 inoculations were made in the growing tips of
healthy vines. The incisions were made with a sterile scalpel
at the nodes, one internode from the growing portion of the end of
the runner. A small amount of crushed leaf tissue taken from
the diseased plants was used as the inoculum. Observations were
made continuously until November 20 when the field was dug,
and at no time on any of the inoculated plants were any symptoms
of mosaic detected.

A general inspection was made at Hastings of the potato seed
obtained from sources outside the state during the latter part
of December. The seed to be planted on 28 farms were exam-
ined and, in every instance, were found irregular, sunken, dark-
brown areas, varying in size from minute spots to the area of
the tuber. This peculiar spotting was found on all varieties of
seed. Certified stock was always found less spotted than common
Seed potatoes arrived at their Florida destination in such
bruised and cracked conditions that in many instances 50 per-
cent of the tubers necessarily had to be discarded as totally
unfit for seed. Most of the growers, however, discarded only
those tubers showing serious decay, throwing out these decayed
parts when the seed pieces were cut. Practically all potatoes
shipped to Florida for seed are shipped in 150-pound burlap bags
and upon arrival at their destination are stored in the open in
this condition. These bruised seed potatoes were subjected to the
attacks of the fungus organisms. More than half of the seed
that had to be discarded were thrown out because of infections
of the various Fusarium species.
During the third week of February the northern half of the


Annual Report, 1923

state was subjected to freezing temperature on two nights.
Observations were made in the potato fields following these
freezes. Previous to this time about 96 percent of the fields
showed the green plants in the different stages of development.
Many of the fields planted in December were in bloom and the
vines had almost hidden the ground. These suffered severely.
The vines were frozen back until only a few inches of the main
stalk remained. Most of the fields, however, were less severely
A large number of the fields were visited and when places
were found where the plants failed to come back, the seed piece
was dug out. Two distinct conditions were noted: First, the
seed piece for some reason had not sufficient vitality to send out
another sprout, the eye of the seed piece was too close to the cut
edge or, as in many instances the seed piece was from the stem
end of the original tuber. These conditions prevailed in almost
all of the fields mentioned above in which the seed piece was hard
and sound, apparently uneffected by any disease. Second, almost
the same conditions as given above were noted in which the
seed piece was unsound, either partly or wholly decayed. A
safe estimate would be that from 30 to 40 percent of the seed
pieces that failed to develop new sprouts were found to be de-
cayed. The percentage of seed pieces that failed to develop new
sprouts ranged from 5 to 50 percent, averaging about 15 percent.
Counts were made in 15 fields. It was noted that the stand in
fields planted with certified seed stock was reduced less by the
freeze than the stand in other fields.

After making observations in the potato fields near Hastings
during February, it was observed that the weak plants grew
most often from the stem-end pieces of the old tubers.
A quantity of Spaulding Rose No. 4 seed were secured and
taken to Gainesville where they were cut and planted in five rows
of forty-five hills each on the Experiment Station grounds.
The seed were planted February 24 and dug May 25.
The first of the five rows was planted with blossom-end seed
pieces, the second row with stem-end seed pieces, the third row
with alternate stem- and blossom-end pieces and the fourth and
fifth rows with middle pieces. The yields were as follows:
Row No. 1.....................-.......--...--..... ...------- 44 pounds
Row No. 2......--....... ..... ...........-----------29 pounds


Florida Agricultural Experiment Station

Row No. 3......................... ........................... .........41 pounds
Row No. 4......................... .... ............. .. ....... ....42 pounds
Row No. 5........................ ..................40 pounds
It will be seen that the blossom-end seed pieces in the first row
yielded 35 percent better than the stem-end seed pieces in the
second. The yield of row No. 3, which was planted alternately
with blossom-end and stem-end seed pieces, is the same as the
average for the fourth and fifth rows which were planted with
the middle seed pieces. The average yield of the third, fourth
and fifth rows is the same, their yields averaging 7 percent less
than row No. 1, planted with blossom-end seed pieces, and 29
percent better than row No. 2, planted with stem-end pieces.

A barrel each of Irrigated, Spaulding Rose No. 4 from Wyom-
ing, Bliss Triumphs from Nebraska, and Russet Rurals from
Michigan certified seed potatoes were planted in the vicinity of
Hastings and compared with Spaulding Rose No. 4 seed from
Maine and New York, as to adaptability to this state and cli-
mate, and as to yield.
The Wyoming seed were planted by J. L. Middleton, of Elkton,
and compared favorably with New York certified Spaulding
Rose No. 4 in yield and freeness from disease.
The Bliss Triumphs were planted by Frank Johns, of Hastings,
and in comparison with the Spaulding Rose No. 4 from Maine
were a little darker green in color, less branched and slightly
more subject to attacks of late blight. There was less of other
common diseases in the Bliss Triumph than in the Spaulding
Rose No. 4. The former yielded 54 barrels and the latter 50
barrels to the acre, resulting in a 7 percent increase in yield in
favor of the Bliss Triumph.
The Russet Rurals were planted by H. O. Hamm, of Palatka.
In comparison with the Spaulding Rose No. 4 from Maine, they
came thru the ground a little later, developed a less branched
and more erect top, and showed less late blight. They also pro-
duced a 10 per cent better yield of which approximately 98
percent were graded U. S. No. 1, while the Spaulding Rose No. 4
graded from 80 to 85 percent U. S. No. 1. Mr. Hamim states, "We
think enough of them to plant several acres another year so that
we can get a better test."


Annual Report, 1923

Certain potato fields in which certified and uncertified seed
were planted side by side were observed during the growing sea-
son and the yields determined.
The results obtained in a 32-acre field owned by Win. Scoville
showed that there was 59 percent more disease in the uncertified
than in the certified plots. In this field the yield of the certified
plots was 18 per cent more than the yield of the uncertified plots
on the acre basis. The certified stock produced 54 barrels and
the common stock 44 barrels to the acre. Ten barrels sold at
$5.50 each, netting $55. The certified seed cost $1.35 more to
the bag than uncertified seed. Since five bags plant an acre it
is necessary to deduct this extra cost (5 bags @ $1.35 equal
$6.75) from $55, the amount secured from the sale of ten barrels
of potatoes, thus resulting in a profit of $48.25 an acre secured
by planting certified seed.
Another field owned by G. W. Atkinson, of Federal Point,
showed that uncertified seed produced 55 barrels to the acre while
the certified seed produced 63 barrels, or an increase of 13 per-
cent. The uncertified seed cost $3.65 and the certified cost $5 a
bag. The extra acre dost of certified seed was $6.75. At $5 a
barrel the certified stock was sold for $315 an acre from which
the extra cost of $6.75 an acre for certified seed was deducted,
leaving a total of $308.25.
At $5 a barrel the uncertified stock sold for $275. From
$308.25 subtract $275.00; this leaves $33.25 which was the acre
profit realized by planting certified rather than uncertified seed,
other conditions being the same.

A series of dusting experiments conducted in co-operation
with Wm. Scoville, of Elkton, in which he used commercial cop-
per-lime dust to control blight diseases were of special interest,
since the fields dusted contained several brands of common seed.
Two applications of dust were used, averaging about 20 pounds
to the acre for each application. The dust was applied efficiently
with a tractor power machine. The yield of the dusted plots
which together consisted of 28 acres averaged 45 barrels to the
acre, while the check plots of four acres produced 40 barrels to
the acre. Thus the dusted plots produced a 11.2 percent better
yield than the check plots.


Florida Agricultural Experiment Station

When the yield for 10,000 check and dusted plants was com-
pared, rather than the acreage, it was found that 10,000 check
plants yielded 47.7 barrels while 10,000 dusted plants yielded
58.3 barrels, showing an 18 percent increase in yield of the dusted
An experiment similar to the one noted above was conducted
by Walter Proctor, of Hastings. He used copper-lime dust,
applied with a motorized dusting machine. Four applications
were made in which a total of 64 pounds of dust was applied to
the acre. Twenty acres were dusted in the daytime, nine acres
were dusted at night and one acre was left as a check.
* The check .plot yielded 40 sacks of potatoes to the acre. The
plot dusted in the daytime yielded 53 sacks to the acre. The
plot dusted at night yielded 70 sacks to the acre. Thus the dusted
plots averaged 35 per cent better in yield than the check plots.
The plots dusted in the daytime averaged 25 percent better in
yield than the check plot. The plots dusted at night averaged 43
percent better in yield than the check plot. The plot dusted at
night averaged 24 percent better in yield than the plot dusted
in the daytime.
"Bodo" Paste vs. Copper-Lime Dust
A series of experiments were conducted by G. W. Atkinson
at Federal Point. The plot sprayed was divided into two parts.
One half was sprayed with bordeaux mixture made from Bodo
paste, by the 4-4-50 formula, and the other half was dusted with
copper-lime dust. The yields of the two plots were practically
the same. Blight attacked the sprayed plots first. The cost of
the Bodo paste was $1.59 to the acre more than the dust and the
cost of the application was twice as much.
Copper-Lime Dust vs. Homemade Bordeaux Mixture
C. W. Smith, of Hastings, sprayed five acres with homemade
bordeaux mixture and dusted five acres with copper-lime dust.
The bordeaux mixture was applied with a tank pressure of 175-
pounds. The dust was applied with a traction power duster. A
small check plot was left untreated.
The dusted plot yielded 75.5 barrels to the acre. The sprayed
plot yielded 75 barrels to the acre. The check plot yielded 60
barrels to the acre. Thus the sprayed and dusted plots yielded
almost the same and each treated plot averaged 20 percent better
than the untreated plot. The.acre cost for applying the dust
was $3.10 more than for that of the bordeaux mixture.


Annual Report, 1923

A list of the diseases found in Florida during the year is
given below. These diseases were reported by various members
of the Experiment Station staff.

RUST (Uropyxis amorphae (Curt.) Schrot.) was collected dur-
ing May and June on this host plant and was severely attacking
the leaflets and defoliating the whole plant. Both uredinial and'
telial stages were present.

Specimens of fern have been received in diseased conditions
which have, upon examination, revealed in a majority of cases
Phoma sp. It is reported occasionally as being very severe in
ASTER YELLOWS (Fusarium sp.) was received for identifica-
tion. It has been severe in isolated places in the state.
ANTHRACNOSE (Colletotrichum sp.) was recorded from Tampa,
the only instance in the state.

ALGAE AND LICHENS: These organisms are common on the
leaves of the avocado, especially on the lower shaded leaves. The
injury consists in a reduction of the leaf area which in certain
instances amounts to 5 percent. Their occurrence was general
where avocados are grown.
ANTHRACNOSE (Colletotrichum gloeosporioides Penz.) was re-
ported scatteringly from the areas where the host plant grows.
It caused considerable damage to the younger twigs and seed-
lings which included most of the specimens received. The fruits,
were also attacked but the seriousness of the fruit disease was
not obvious.
BACTERIAL DISEASE. The organism causing this disease was
not cultured. Specimens were sent in from the lower west coast.
BLOTCH (Cercospora sp.) : The spots caused by this fungus
were rare on leaves and twigs of trees but were occasionally
found on the fruit. It did not prove serious during the year.
FUSARIUM sp.: This fungus was apparently the.cause of the


Florida Agricultural Experiment Station

excessive premature drops of fruit. It was isolated from prac-
tically all specimens sent in to this laboratory. The vascular
systems of the stems and the vascular systems of the fruit were
in each case badly discolored by this fungus.
LEAF BLOTCH (Pestalozzia guepini Desm. var. vaccinii Sh.):
This fungus appears to be of a weak parasitic nature, in as much
as its occurrence was noted on leaves of the host plant previously
injured by sunscald, sprayburn, or mechanical means. It was
prevalent and persistently attacked' leaves under conditions
mentioned above.
LEAF SPOT (Phyllosticta sp.) : Specimens of this disease were
sent in twice during the year. It appeared to be of minor impor-
SCAB (Cladosporium citri (pro. tem.) Massee) was the most
common and probably caused more loss than all the other known
avocado diseases in Florida. It was reported from every area
of the state where the avocado is grown and in certain instances
caused considerable damage. The disease on the foliage was the
most serious during March, and on the first fruit during May
and June.
(EXOBASIDIUM AZALEAE Pk.) : Specimens from but one place
in the state have been sent in during the year. The fungus at-
tacked the leaves in this instance.
RUST (Dieacoma melancepholum (Sydow) Arth. and Fromme)
was reported from three different localities in the state, exclus-
ive of Jacksonville where it was collected last year. Wherever
found its infection was quite general.
LEAF SFOT (Bacteria sp.), caused by a bacterial organism, was
common on bamboo leaves. Plants become partially defoliated
from the results of the disease.

A bacterial disease was reported on banana from St. Cloud.
No serious damage resulted, however.
PINK MOLD (Cephalothecium roseum Cda.) was found on
banana leaves, but from the nature of the infections it appeared
to be a weak parasite and no serious damage resulted.
LEAF SPOT AND FRUIT SPOT (Gloeosporium musarum C. & M.)


Annual Report, 1923

caused extensive losses both by reducing leaf surface and because
of the disease produced on fruit. The disease was common on the
fruit on the market and often was a limiting factor in its sale.
LEAF SPOT (Rhytisma sp.) was found to be the cause of almost
the complete defoliation of this plant. It was not common.
ANTHRACNOSE (Colletotrichum lindemuthianum (Sacc. &
Magn.) Br. & Cav.) was reported from practically every bean
growing community of the state. It did not prove serious except
in isolated localities where the loss was slight. It was most
serious during October and March.
HOLLOW STEM (Corticum vagum Berk. & Curtis) was of con-
siderable importance in the Florida bean industry. It was re-
ported as being widespread, associated with'wet weather, and
caused extensive damage. A 15-acre field near Hastings was a
total loss and several fields in the vicinity suffered a loss of
from 40 to 80 percent. The plants were killed while having but
from four to six leaves. The fungus weakened the stem so that
the plants fell over while yet green and healthy looking.
LEAF SPOT (Cercospora cruenta Sacc.) was reported from
Quincy as doing some damage but the loss was not reported.
RUST (Uromyces appendiculatus (Pers.) Lev.) was common
on beans, especially in June, and in several instances caused se-
vere defoliation soon after blossoming time. The disease was
localized, however, and no severe losses resulted.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was prevalent and
widely scattered. It proved more serious during May and June
than during other months of the year. The fungus penetrates
the stem at the surface of the soil, girdles it and causes the plant
to die.- The pods are also subjected to the ravages of this dis-
ease whenever they hang so low they come in contact with the
MOSAIc (cause unknown): This disease was not common in
Florida this year. In fact, only scattered reports of its occur-
rence are at hand.
LEAF SPOT (Cercospora beticola Sacc.) was reported as doing
from 40 to 50 percent damage in certain fields near Quincy. It


Florida Agricultural Experiment Station

Was common on beets thruout central and southern counties,
'resulting in certain cases of losses from 5 to 10 percent.
ANTHRACNOSE (Gloeosporium begoniae Magnag.), reported
friom Palatka, resulted in a complete girdling of the stem and
collapse of the plant.
:, BLOTCH (Cercospora rubi Sacc.) was collected in the state but
was not of economic importance.
Ji'ORANGE RUST (Kunkelia nitens (Schw.) Arth.) was collected
'in several places in the state in March and April. In localities
where it was found it had almost killed out wild bushes. It is
generally distributed.
.: LEAF SPOT (Phyllosticta sp.) was collected at Gainesville. Its
[range and importance was not noted.
SLEAF SPOTS: Spots caused by species of Lichens were common
lin moist, shaded places but were not of economic importance.
ANTHRACNOSE (Gloeosporium sp.), reported on this host, was
not common and caused no damage.
LEAF SPOT (Alternaria brassicae (Berk.) Sacc.) was collected
on cabbage in the central part of Florida but did not prove ser-
ious except on late plantings which were not marketable until
after warm weather developed. This disease was common.
BLACKLEG (Phoma lingam (Tode.) Desmaz.) was reported
from scattered areas of the state. In a small field from 15 to
25 percent of loss was reported by W. B. Tisdale.
BLACK ROT (Bacterium campestre (Pam.) E. F. S.) was found
in both the Sanford and Micanopy trucking areas but elsewhere
'it was scarce. The disease caused some damage in the Sanford
district. W. B. Tisdale reported its occurrence as common in
:gardens of western Florida.
BLOTCH (Cercospora bloxami B. and Br.) was found on the
Experiment Station plots at Gainesville. The disease was not
widespread or serious.
DAMPING-OFF (Pythium sp.) was one of the most serious dis-
eases of cabbage in the seedbed. The fungus killed the plants
soon after they were up.


Annual Report, 1923

DOWNY MILDEW (Peronospora parasitica (Pers.) de By.) was
reported in seedbeds by W. B. Tisdale at Quincy and was also
found at Gainesville. The fungus was found widely scattered
in the trucking areas of the state. It was severe on half-grown
The following organisms were collected as parasitic upon the
host plant and did considerable damage: (Colletotrichum sp.,
Gloeosporium sp., Pestalozzia sp., Phoma sp., and Leptotherium
pomi (M. & F.) Sacc.), named in the order of their importance.
The Anthracnose diseases were by far the most important. A
severe outbreak was reported from Perry in which a consider-
able number of trees were killed. It was found that the severity
of the disease was probably due to association with thrip injury.
RUST (Puccinia cannae Hen.) was found in St. Petersburg. It
was well scattered over the plants, killing the older leaves.
ANTHRACNOSE (Colletotrichum lagenarium (Pass.) Ell. &
Hals.) proved one of the-most serious diseases .of the host plant
in Florida last season. It was found early in April and developed
rapidly until June, the end of the cantaloupe's growing season.
In several fields near Jennings and Williston it caused a loss of
from 10 to 20 per cent. Attempts to control the fungus with
copper-lime dust did not prove satisfactory.
DOWNY MILDEW (Pseudoperonospora cubensis (B. & C.) Ros-
tow.) was the worst disease attacking cantaloupes in the state
during the year. The disease was widespread and in practically
every field was the principal factor limiting the yield. Practi-
cally no field escaped the disease, even tho spraying or dusting
was done diligently. The fungicides helped considerably to con-
trol the disease but did not appear efficient.
POWDERY MILDEW (Erysiphe polygoni D. C.) was reported as
quite prevalent over the state but in no case was it the causal
agent of losses.
WILT (Fusarium incarnatum (Desm.) Sacc.) was reported
from various localities by florists. It caused- wilting and final


Florida Agricultural Experiment Station

destruction of the plant. It was of much importance in isolate
RUST (Uromyces caryophyllinus (Schr.) Wint.) was collect
at Gainesville and Jacksonville, the only places in the state r(
porting it.
LEAF BLIGHT (Macrosporium ramulosum Sacc.) reduced th
yield in one field by 50 percent. The disease was noticed firs
when the host plants were almost six inches high. The olde
leaves were attacked first and soon killed. The disease prc
gressed rapidly and in three weeks had killed the entire plants
It was collected during May.
LEAF SPOT (Cercospora ricinella Sacc. & Berl.) was general
widespread over the state and caused partial defoliation in sei
eral instances.
RUST (Puccinia menthae Pers.) was found in abundance i
the woods near Gainesville. An aecial stage was found o
the same plants as the telial stage, showing the cluster cups i
LEAF SPOT (Alternaria brassicae (Berk.) Sacc.) was collect
at Jacksonville and in numerous places in the vicinity of Gainei
ville. It did not prove serious except on plants that were plante
late; it was most serious in April.
EARLY BLIGHT (Cercospora apii Fr.) of celery was found
in every place in the state where celery was grown. It wi
especially destructive in the vicinity of Sanford, Bradentowv
Homestead, Goulds, Vero, Palatka and Oakland. The disea,
was more severe last season than previously, due to the pa:
ticularly warm weather during the early growing season. A
tempts were made to control the disease but no absolute contri
was obtained, except in the seedbeds by spraying with bordeau
mixture. The disease was not controlled effectively in the field
This is one of the most serious celery diseases in the state.
BLACK HEART (cause unknown) was the most serious as we
as the most baffling of the celery, diseases. It was very serious i
Sanford, causing the total loss of several fields of from 5 to 1


Annual Report, 1923

acres. In most cases it showed up rather late. It was reported
also from the vicinity of Bradentown; the damage there, how-
ever, was slight.
DAMPING-OFF (Rhizoctonia sp.) proved a serious factor in
seedbeds. A 10-percent loss was reported from Bradentown;
and in one instance near Sanford the seedbed loss was approxi-
mately 60 percent. Soil moisture and shade appear to be the
most important factors concerned with the control of the
STUNTING (probably poor setting) of celery was reported as
serious in the vicinity of Bradentown. The occurrence of the
condition was noted first in December and during the following
month was found to be quite widespread in that vicinity. The
disease appeared soon after transplanting. The affected plants
remained small, were stunted, and tended to become more or
less rosetted. Their development was slow. Such a field appears
very uneven.
MYXOMYCETE (Physarium gyrosum) was collected from half-
grown celery plants. It was of a dark chocolate-brown color
and sporulated abundantly. Some of the spores were mounted
on a glass slide in distilled water and in 30 minutes they began
to germinate. The spores appeared to swell slightly, then their
walls to crack and part, revealing a naked protoplasm. The
spore wall continued to break until the two halves were nearly
separated. Then the small plasmodium emerged and immediate-
ly began amoeba-like movements. The organism was not par-
DAMPING-OFF (Pythium debaryanum Hesse.) caused losses
ranging from 5 to 40 percent of certain seedbeds in the vicinity
of Sanford. Wherever the fungus was found, it proved serious.
LATE BLIGHT (Septoria apii (Br. & Cav.) Chester) was col-
lected at Sanford only, being scattered over a small field. It was
not of economic importance.
ANTHRACNOSE (Gloeosporium sp.) was collected on the fruit
of this plant; causing a black rot. The host plant is not exten-
sively grown.
LEAF SPOT (Cercospora cerasella Sacc.) was common on the
host plant in the vicinity of Gainesville. Many trees were en-
tirely defoliated by this fungus.


Florida Agricultural Experiment Station

-LEAF BLOTCH (Pestalozzia longiseta Speg.) was found in the
vicinity of Gainesville. It appeared prevalent on sun-scalded
LEAF SPOT (Phyllosticta lamo-cerasi Sacc. & Speg.) was found
near Gainesville and reported from Pensacola as doing consid-
erable damage to hedges of the host plant, causing defoliation.
LEAF SPOT (Cercospora bloxami B. & Br.) was first collceted
near Jacksonville, where it proved disastrous to a ten-acre field;
60 percent loss was reported. The disease was also found at
St. Augustine where it caused the total loss of a small garden
patch. The disease spread rapidly in the field, attacking plants
from the seedling stage to maturity.
BLACK MOLD (Macrosporium brassicae Berk.) was collected
near Gainesville, but appeared to be of no economic importance.
WILT (Fusarium sp.) was a disease of local distribution and
was of no economic importance.
LEAF SPOT (Phyllosticta chrysanthemi Ellis & Deam.) caused
the defoliation of plants in Gainesville just before blossoming
time. It was widely scattered and severe, killing the host plants.
BUD ROT (organism not isolated) was reported as doing con-
siderable damage near Palm Beach. The green color disappears
from the leaves of affected trees. The lower ones droop, follow-
ed by the younger leaves until all hang, except the terminal leaf,
which usually falls out the top. All the foliage withers away,
leaving the bare pole-like trunks standing. A casual examina-
tion of diseased parts revealed numerous organisms ranging
from bacteria to nematodes.
A somewhat similar disease was noted on Cocus plumosa. As
in the above instances the palms were killed. The first symptom
generally noted was the falling from the crown of the newest leaf
before the blade unfolded. It gave off a putrid odor. The trees
from which the buds have fallen linger for a season or two before
dying, but eventually all diseased trees die.

72 I

Annual Report, 1923


DOWNY MILDEW (Peronospora parasitica (Pers.) de By.) was
collected in Gainesville in several different gardens. It did not
appear to do any damage.
DOWNY MILDEW (Peronospora parasitica (Pers.) de By.)
caused only slight injury to this plant in the vicinity of St.

BACTERIAL SPOT (Bacteria sp.) evidently caused some losses
by killing corn leaves. The spots were small, circular, and did
not coalesce; when numerous they killed the leaf.
EAR MOLD (Diplodia macrospora Ea.) was prevalent and de-
structive in the state this year. It was especially destructive
because the corn usually was put in the crib with the husks left
on and the months following were rainy, favoring the develop-
ment of the fungus.
ROOT ROT (Fusarium moniliforme Shel.) was especially de-
structive to field corn. A 30-acre field near Quincy showed from
15 to 30 percent loss from this disease. It was especially de-
structive in the northern part of the state. It also was reported
from the central part.
LEAF SPOT (Helminthosporium turcicum Pass.) was prevalent
on corn leaves, showing up first when the plants were from five
to ten inches tall. It was most common and destructive about
tasseling time. The spots were always lenticular-shaped and
often were from seven to ten inches long. It killed the leaves
rapidly. It was reported wherever corn was grown, being es-
pecially destructive farthest north.
BLACK MOLD (Macrosporium sp.) was recorded as causing
conspicuous spotting on the leaves; it was not prevalent.
LEAF SPOT (Phyllosticta sp.) was found on leaves of corn, but
was of no serious consequence.
RUST (Puccinia sorghi Schw.) was found on corn in various
parts of the state. The first collection was at Vero in February,
when plants were three feet tall. Since then it has been found
widespread but seldom doing damage. During July some speci-
mens were collected and the germination tested twice a month
thereafter. It was found that- all germination had ceased by
December 15. 'The material was not subjected to a temperature


Florida Agricultural Experiment Station

below 500 F. These experiments, supplemented by previous
work of the writer,1 appear to eliminate temperature as the con-
trolling factor in the longevity of urediniospores of puccinia
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was not serious
this year. Losses nowhere exceed 2 percent.
SMUT (Ustilago zeae (Beck) Bug.) was collected in only a few
scattered fields where infection was less than 1 percent; losses
were negligible.
ANGULAR LEAF SPOT (Bacterium malvacearum E. F. S.) dur-
ing the year proved to be one of the most widespread cotton dis-
eases. It was found in all fields seriously cutting down the leaf
area and not infrequently killing individual plants by defolia-
tion. Two percent loss of plants was noted in a small plot near
Gainesville. It was serious in the western part of the state.
ANTHRACNOSE (Glomerella gossypii (Sout) Edg.) caused con-
siderable loss in the state especially from the infections in the
stems and bolls of the plant. It was common wherever cotton
was grown.
LEAF SPOT (Cercospora gossypina Cke.) was collected in a sin-
gle place in western Florida. No losses were noted.
BLACK MOLD (Macrosporium nigricans Atk.) was collected
from cotton but was not prevalent and caused no loss.
DAMPING-OFF (Rhizoctonia sp.) was serious during the early
part of the season, due to considerable moisture. In a large
number of fields in Columbia and Alachua Counties the stand
was reduced from 30 to 60 percent. A 40-acre field in Columbia
County was a total loss. Near Gainesville several fields showed
a loss of 50 percent in killed seedlings. Replanting was carried
on in most fields in the cotton-growing area.
WILT (Fusarium vasinfectum Atk.) still continues as the
worst disease in the state. It was common, widespread and de-
LEAF SPOT (Amerosporium oeconomicum E. & T.) found near
Gainesville, was serious, causing almost the complete defoliation
of plants. It was widespread over the state.
BLOTCH (Cercospora cruenta Sacc.) was the worst disease of
the host plant in the vicinity of Gainesville. It caused complete
"Studies on Corn Rust." Phytopathology 12: 89-97, 1922.


Annual Report, 1923

defoliation and reduced the yield by 3 percent. It was common
and widespread.
WILT (Fusarium vasinfectum var. tracheiphila E. F. S.) was
not found to be common. One seven-acre field at Palma Sola,,
however, was a total loss because of infected seed. The disease
at flowering time was common.
DAMPING-OFF (Rhizoctonia sp.) caused considerable apprehen-
sion among growers, especially when the plants were in the seed-
ling stage. Severe infections were scattered, however.
LEAF SPOT (Pestalozzia guepini Desm.) resulted in the defolia-
tion of severely infected plants. In general the disease was not
serious although it was widespread.
LEAF SPOT (Gloeosporium sp.) was reported quite common
over the state.
ANGULAR LEAF SPOT (Bacterium lachrymans E. F. S. and
Bryan) was not severe last season. The disease was checked
fairly well near Williston by the application of a liquid bordeaux
spray. The sprayed plants yielded well while the check rows
were not picked, being a total loss. The occurrence was local.
ANTHRACNOSE (Colletotrichum lagenarium (Pass.) Ell. and
Hals.) was serious on fall cucumbers during September and
October, being spread apparently from watermelon fields nearby.
A fairly good control was obtained by the application of copper-
lime dust. The disease was not so prevalent during the spring,
causing little damage even tho widely scattered. It was reported
from many points in the central and northern parts of the state.
It caused a loss estimated at from 1 to 2 percent.
DOWNY MILDEW (Pseudoperonospora cubensis (B. & C.) Ros-
tow) was the worst by far of all the cucumber diseases reported
during the year. It was found in December in the southern
part of the state, in January at Ft. Myers, in February at Palm
Beach, in March at Wauchula, in April at points in central parts,
and within a few days later over the northern counties. The
most severe losses observed were in Hardee County where the
loss on a whole averaged 80 percent of the crop. Conditions were
favorable for the fungus at the time and bordeaux spray seemed
to have little effect upon its progress. Thruout the central part


Florida Agricultural Experiment Station

of the state the loss was much less, averaging from 15 to 20 per-
cent. In the vicinity of Gainesville the harvesting period was
reduced a week to ten days, resulting in a loss of 10 percent. The
northern counties were somewhat later in the development, and
their losses were close to 35 percent. In considering the whole
state the losses from the disease were severe, averaging approxi-
mately 30 percent. Spraying experiments in the vicinity of Ocala
and Gainesville showed that liquid bordeaux was more effective
in checking the disease than copper-lime dust, altho the control
in every case was poor, necessitating improved methods. Un-
sprayed fields generally were a total loss.
MOSAIC (cause unknown) was reported from two fields in
Pasco County. No loss was noted.
WILT (Bacillus tracheiphilus E. F. S.) was not common in the
state and no serious losses were attributed to it.
LEAF SPOT (Bremia lactucae Regel.) was common on this host
plant which undoubtedly plays an important role in harboring
this fungus when lettuce is not in cultivation. It was collected
at Gainesville where 100 percent of the plants were infected
BLOSSOM-END ROT (Alternaria citri Pierce) was rather prev-
alent thru the state. It is believed that the extreme rainy
weather of last summer was favorable for its development. The
disease was reported on the following varieties of oranges:
Ruby Blood, Parson. Brown, Pineapple, Jaffa, Tangerines and
Valencia. The later varieties were not as badly affected as those
which ripened early in the fall. The infection in many groves
varied from 5 to 25 percent.
BLIGHT (cause unknown) was serious in certain areas of the
state. In several groves along the east coast a third of the groves
remained unproductive. This resulted from the fact that many
trees were taken out of the grove and reset with young trees.
DIEBACK (cause unknown) remains one of the worst diseases
of the citrus grove. The annual damage done from this disease
is large. It was quite common in all areas of the state. Trees
on light sandy ridges were most severely affected.
WITHERTIP (Colletotrichum gloeosporioides Penz.) was re-
ported from several areas of the state. There was in some places
a rather severe epidemic of this disease. In young nurseries


Annual Report, 1923

where the water had been high and injured the trees the disease,
was severe.
SCAB (Cladosporium citri pro tem Mass.) : Was rather
severe this spring on young fruit and tender twigs and leaves.
There were more inquiries concerning the control of scab this
season than for several years previous. Spring was cool and
rainy which favored the development of scab. Spraying with:
3-3-50 bordeaux-oil was recommended. The time of application is
in spring before growth begins and again ten to twenty days,
after the petals fall.
FOOT ROT (Phytopthora terrestria Sherb.) was reported as do-
ing damage to some nursery trees. It is rather prevalent in old
seedling groves. It is worse on poorly drained land than on any,
other type of soil.
MELANOSE (Phomopsis citri Faw.) was severe this season be-
cause the early rains came before the fruit was immune. Where,
spraying with 3-3-50 bordeaux-oil had been done the disease was:
controlled. The spraying should be done from 10 to 20 days
after the petals fall. It is necessary to spray before the rains.
STEM-END ROT (Phomopsis citri Faw.) was reported from all
citrus areas, being severe in some groves. This disease appears
only on ripe fruit or fruit about ripe.
DAMPING-OFF: There was considerable complaint from all
parts of the state because the young citrus seedlings were damp-
ing-off at the ground line. Examinations were made and a fun-
gus isolated; it proved to be Rhizoctonia sp., and formed abun-
dant micro sclerotia.
SCALY BARK (Cladosporium herbarium (Pers.) L. K. var.
citricolum Faw.) seemed to spread slightly during the year,,
Quarantined areas were increased by the addition of new prop-;
erty which was found infected.
FELTY FUNGUS (Septobasidium pedicillatum (Schev.) Pat.)
was common, being reported from various areas. In one partid.
ular locality it was found associated with a severe infestation of
scale. ..
Cephaleuros virescens Kunze was reported on citrus from-,var-,
ious localities. In one instance the grower claimed that it did
much damage by killing back the young branches. Control was.
reported by spraying with lime-sulphur.
CITRUS CANKER (Bacterium citri (Hasse.) Jeble) -was re,
ported from Davie. No new properties were reported, A ,few:.


Florida Agricultural Experiment Station

trees on the infected properties reported last year were de-
ANTHRACNOSE (Colletotrichum gloeosporioides Penz.) was re-
ported from 'one area as doing considerable damage to the fruit.
In the northern part of the state, leaves which had been injured
by the frost on February 19 showed considerable infection from
this fungus.
DIPLODIA sp.: Specimens of diseased bark of citrus were re-
ceived where. this fungus was evidently causing stem-end rot
and gummosis.
LIGHTNING INJURY to citrus was reported from all areas of
the state. The fact that the tender branches began dying on
trees surrounding the one that was struck caused many growers
to believe this phenomenon a disease.
SPRAY INJURY: Many specimens of citrus fruit were sent into
the office injured by both oil spray and lime-sulphur sprays.
One specimen showed that the part had been killed when the
fruit was quite young; as the fruit grew the dead part became
depressed and finally broke away from the fruit.
LEAF SPOT (Cercospora cornicola T. & E.) was a conspicuous
disease, in every case severe, often causing complete defoliation
in early summer. It was common on native and cultivated
plants and was widespread.
BACTERIAL WILT (Bacterium solanacerum E. F. S.), a common
disease, was found well distributed wherever the host plant was
grown. It Was observed attacking plants in all stages of devel-
opment but appeared most severe on plants just before blossom-
ing time. Losses in the state due to this disease are from 2 to
4 percent.
FRUIT SPOT (Diplodia sp.) was found in a garden in Gaines-
ville doing considerable damage.
STEM ROT (Nectria ipomoeae Hals.) was sent in from Braden-
town where the Fusarium stage was causing the plants to wilt.
After being placed several days in a moist chamber on filter
paper the perithecia developed, containing mature spores. The
Fusarium also sporulated abundantly in the moist chamber.
FRUIT ROT (Phomopsis vexans (Sacc. & Syd.) Harter) was
common wherever eggplant was grown and caused a loss of
approximately 10 percent. A ten-acre field near Sebastian


Annual Report, 1923

showed a loss of 80 percent, the fungus destroying most of the
fruit and a large number of the plants. No fields were found
that were entirely free of the disease.
LEAF SPOT (Phyllosticta hortorum Speg.) was common and
widespread. The actual damage was slight, however, as the fruit
was seldom attacked and the leaves were never killed.
DAMPING-OFF (Rhizoctonia sp.) caused considerable damage
in seedbeds thruout the state.
FOOT ROT (Sclerotinia libertiana Fckl.) caused some damage in
a field near Sanford in January; the plants fell over and the fun-
gus covered all parts touching the soil. It was not common on
this host.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) on eggplants was
serious in the vicinity of Gainesville. One field of 20 acres suf-
fered seriously, 60 percent of the plants being killed before fruit-
ing time. The fungus attacked the plants at about the surface
of the soil. The stem was girdled and the plant wilted. Some
plants had fallen over but it was not a general symptom of the
disease. The fruiting bodies were usually abundant around the
stem on the soil at the time the wilting was discovered in the
field. This disease was especially destructive during May and
Elephantopsis tomentosus
RUST (Coleosporium elephantopodus) was collected near
Gainesville in October.
ANTHRACNOSE (Colletotrichum carica S. & H.) was more or
less common but not serious last season.
LIMB BLIGHT (Corticium salmonicolor Kanst.) during the year
was reported as serious from several different parts of the state.
The fungus usually was found first on the smaller branches,
gradually working its way down to the larger limbs, causing
extensive injury by killing large limbs. Pruning proved an effi-
cient control method.
LEAF BLIGHT (Rhizoctonia microsclerotia Matz.) was prev-
alent last season on fig trees on the Experiment Station plots.
The disease caused considerable blight of fruit and young growth.
The leaves suffered severely, being completely killed by the fun-
gus which advanced up the petiole and attacked the blade.
Affected trees usually were defoliated entirely. Three trees were
sprayed with 4-4-50 bordeaux mixture on May 16 and on June


Florida Agricultural Experiment Station

:1. Not a single infection was found on these three sprayed
trees, while 20 percent of the twigs of the three check trees (al-
most touching the sprayed trees) showed infection and the
Disease was spreading rapidly. The spray probably could have
,been applied two weeks earlier, controlling the disease as well
and avoiding the discoloring of the small fruit.
, RUST (Physopella fici (Cost.) Arth.) was the most serious of
the fig diseases in Florida. The rust caused complete defolia-
tion of the trees and consequently hindered growth. Usually
it does not develop until after the fruit is picked in July. It
was common and widespread.
WILT (Bacterium sp.) was found to cause the death of the
geranium near. Tampa and Plant City. It was not common but
was severe where found.
ANTHRACNOSE (Sphaceloma ampelinum de By.) was common
wherever grapes were grown in the state. It was collected dur-
ing September, October, December and June. Losses due to this
fungus averaged 2 percent for the state.
BLACK ROT (Giugnardia bidwelli (Ellis) V. & R.) was the
worst grape disease in the state, being reported from all grape-
,growing areas and being found on native vines as well as cul-
tivated plants. It was collected every month of the year, except
February and March. Loss from this disease over the state
will approach from 5 to 8 percent.
,.. DOWNY MILDEW (Plasmpora viticola (B. & C.) Berl. & DeT.)
was collected at Mt. Dora and Gainesville. The collections at
Mt, Dora were on wild plants. No serious losses resulted from
,this disease.
LEAF SPOT (Isariopsis claifspora Sacc.) was found to be ser-
Jous in a vineyard near Gainesville. The fungus had caused al-
_most complete defoliation. It was reported serious at DeLand
also. Economic losses were not calculated.
LEAF AND FRUIT BLIGHT (Pestalozzia unicola Speg.) was more
or less common last season, causing some defoliation and a rot-
ting of fruit. It was of considerable importance on marketable
fruit. ,
, RUST (Physopella vitis (Thum.) Arth.) was collected in No-
.vember and February near Tampa, Orlando and Gainesville. It
,as not -serious and caused only slight defoliation.

, 80R

Annual Report, 1923

Attention was called to certain diseases on grasses, principally
around Gainesville and on the Experiment Station plots. The
following fungi were collected on the hosts as designated.
BERMUDA GRASS was attacked at different places by Rhizoc-
tonia sp. and Sclerotium rolfsii Sacc. Small patches in these
lawns were completely killed.
CRAB GRASS (Syntherisma sanguinalis) was found severely at-
tacked by Piriculania grisea (Cke.) Sacc. which killed practically
all the leaves.
Elerisene sp. was found attacked by Vermicularia sp.
GAMA GRASS was found severely infected with rust, Puccinia
graminis Pers.
JOHNSON GRASS was almost killed out by the leaf spot caused
by Helminthosporium gramineum (Rab.) Erik.
RHODES GRASS (Chloris grueva) occasionally was found ser-
iously attacked by Helminthosporium sp.
Paspalum sp. was collected. It harbored both Claviceps pur-
purea (Fr.) Tul. and Fusarium sp.
SMUT GRASS (Sporobolus indicus) has always been attacked by
Helminthosporium ravenelii, Curt. & Berk. This disease is se-
vere, common and widespread. All the plants and usually every
head were infected. It persists from May to October.
Cenchrus echinatus L. was found to be attacked by Ephelis
mexicana Fr. The fungus developed the sclerotia in the sheath
of the flag leaves, involving the inflorescence. The sclerotia were
at first white, of a mushroom consistency, about the diameter of
a knitting needle and from three to five inches long. Later they
became black-spotted and finally turned completely black, with
a glossy appearance on the outside. These sclerotia were collect-
ed and placed in a moist chamber. After two weeks small
Peziza-like cups developed from the sides of the sclerotia con-
taining conidia which germinated readily and were readily cul-
tured. About two weeks later other bodies became visible. They
grew from the sides of the sclerotia, often from the same place
as the peziza-like cups emerged. A small, round stroma devel-
oped and was pushed up by a long stipe, often three centimeters
in length. The stroma was filled with perithecia, which contains
asci and spores of Balansia hypoxylon (Pk.) Atk. Somewhat
later during the rainy season these two stages were discovered


Florida Agricultural Experiment Station

out of doors buried in the sand where dead plants of cenchrus
were to be found.
LEAF SPOT (Phyllochora sphaerosperma Wint.) was found on
this host killing the older leaves. It is common on poor soil.
RUST (Puccinia cenchri Diet. & Halw.) was common on the
host, but it was of no importance.
St. Augustine grass, extensively used for lawns in Florida,
was attacked by Helminthosporium sp., Rhizoctonia sp., and
Sclerotium sp. The latter, however, proved destructive on lawns
and golf courses. Round, brown, dead spots appear up td three
feet in diameter quickly. It was serious on lawns in Gainesville
during the summer.
LEAF SPOT AND TWIG BLIGHT (Cephaleuros virescens) was
common on certain species during the year. Twig development
was held in check and considerable leaf surface lost because of
this organism.
DIEBACK (Colletotrichum sp.) was not common during the
year. Slight damage was reported from San Antonio.
FRUIT SPOT (Gloeosporium psidii Del.) was reported from St.
Petersburg and Gainesville as causing spots on the fruit. Losses
from it were not important.
LEAF SPOT (Septoria sp.) caused a complete defoliation of the
gum trees situated on the campus of the University of Florida'in
the middle of the season. It was not reported elsewhere.
ANTHRACNOSE (Colletotrichum hisbisci Poll.) was collected at
two places in the state but resulted in no serious damage.
BACTERIA (not determined) caused considerable wilting of the
host plant.
WILT (Fusarium berkeleyi Mont.) caused the loss of a number
of plants at Howey. It appeared to be a soil infection.

POWDERY MILDEW (Oidium sp.) was destructive to the -host
plant, especially when it was grown under more or less moist,
shady conditions.


Annual Report, 1923

IVY (Virginia Creeper)
LEAF SPOT (Pestalozzia sp.) caused the partial defoliation and
stunting of these vines in the vicinity of Gainesville.
LEAF SPOT (Cercospora longipes Buller) caused almost a total
destruction of leaves on the host plant in a field near Gainesville.
All leaves were completely killed soon after blossoming time.
KERNEL ROT (Fusarium sp.) affected 100 percent of the ker-
nels in the heads of almost mature plants.

SOUTHERN WILT (Sclerotium rolfsii Sacc.) caused the loss of
these host plants in St. Augustine by girdling the stem at the soil
ANTHRACNOSE (Marssonia panattoniana (Berl.) Magnus)
was found quite well distributed over the lettuce-growing dis-
tricts of the state. In no case, however, was it found to be of a
destructive nature. Always the older leaves were attacked.
These affected older leaves were discarded when packed.
LEAF SPOT (Bacterium sp.) was well distributed in the San-
ford and Micanopy districts. No losses were reported.
BLACK' ROT (Bacterium sp.) was one of the worst lettuce dis-
eases in the state during the year. It was found causing from
1 to 3 percent. damage near Oakland, 4 percent at Orlando,
and 5 percent in fields near Gainesville. A ten-acre field near
Micanopy was almost a total loss from this disease; 90 percent
of the plants were left in the field and many that were cut were
discarded. The disease was most severe in the latter part of the
season (March).
DOWNY MILDEW (Bremia lactucae Regel) was collected at San-
ford in January and at Gainesville in April. The April infes-
tation resulted in some damage. The disease was not reported
BLACK MOLb (Macrosporium cladosporioides Desm.) was
found causing considerable damage to late lettuce during March
near Micanopy. The spotting was plentiful and found on the
young leaves. A loss of 10 percent was noted in a seven-acre
DROP (Sclerotinia libertiana Fickl.) was by far the most ser-
ious disease of lettuce in the state: It was reported as causing


Florida Agricultural Experiment Station

losses from every lettuce-growing district. At Sanford, 30 percent
losses were noted; at Orlando 20 percent; at Oakland, 35 per-
cent; at Ellentoi, 15 percent; at Gainesville, 15 percent; at Pa-
latka, 20 percent; at Quincy, from 15 to 20 percent. Because of
its severity in transit it is much dreaded by the growers of the
GRAY MOLD (Botrytis cinerea Pers.) was a serious disease of
the flowering parts last season. It was also reported on leaves.
LEAF SPOT (Cercospora unicolor S. & P.) was found widely
scattered and prevalent over the state. Little damage resulted,
WILT (Fusarium sp.) ruined several large beds of lilies. No
other reports of it were received.
MOSAIC (cause unknown) was reported widespread over the
state, causing losses of plants at Tampa, Sebastian and Gaines-
WILT (Sclerotinia libertiana Fckl.) was reported as occurring
in a flower bed in Jacksonville, causing some damage.
LEAF SPOT (Sphaeropsis malorum Pk.), altho well-scattered
where loquats are grown, caused comparatively no damage.
ANTHRACNOSE (Colletotrichum sp.) was found well distrib-
uted on Magnolia but causing little damage to foliage or twigs.
ANTHRACNOSE (Colletotrichum gloeosporiodes Penz.) was re-
ported from all areas of the state where the host plant is grown.
It was especially destructive around St. Petersburg and Palm
ALGAE (Ceptaleuros virescens) was observed killing small
twigs and causing numerous spots on leaves.
LEAF SPOT (Pestalozzia guepini Desm.) was the cause of con-
siderable defoliation at Bradentown.
SCAB (Colletotrichum gloeosporioides Penz.) was collected
near Redlands, causing little damage.
FELTY FUNGUS (Septobasidium pedicillata (Schw.) Pat.)'was
found growing on the twigs of the host plant. It is not believed
to be parasitic on mango twigs.


Annual Report, 1923 .

TAR SPOT (Rhytisma acerinum (Pers.) Tr.) was collected on
soft maple on the University of Florida campus. It affected
about 1 percent of the leaves on several trees.
FELTY FUNGUS (Septobasidium pedicillata (Schw.) Pat.), col-
lected at Gainesville, showed the fungus smothering growing
tips of young twigs.
WHITE FUNGUS (Entomophora fumosa Speare) was collected
controlling the mealy bug at Cocoanut Grove.
MILLET (Chaetachloa magna)
DOWNY MILDEW (Sclerospora graminicola (Sacc.) Schr.) was
collected on this host plant at Sebastian, Vero, Hobe Sound and
Palm Beach. This millet, which is widely scattered in the Ever-
glades, was found on volunteer plants in tomato fields near the
places named. Some plants were completely destroyed by the
fungus, others were of a whitish-streaked appearance and exam-
inations revealed the fungus partially covering the plants. Other
less infected plants showed only elongated brown spots on the
leaves, the under side of which was covered with the white con-
idiospores and conidia. Specimens of this disease were sent.to
W. H. Weston, of Harvard, who verified the classification.
LEAF SPOT (Cercospora moricola Cke.) was found destroying
a row of mulberry trees in Gainesville. The trees apparently
were killed back by the disease which caused complete defolia-
tion early in the season and frequently killed back some of the
young, tender twigs.
WHITE RUST (Albugo candida (Pers.) Roussel) was collected
on mustard during January, February, and March in many dif-
ferent places in the state. The damage was of no consequence,
-BACTERIAL WILT (Bacterium solanacearum E. F. S. & Bryan)
was severe on nasturtiums last season, killing practically all
plantings in the vicinity of Gainesville. The first symptoms be-
came evident when the plants began to blossom. One hundred
percent of the plants were affected and most of them died.


Florida Agricultural Experiment Station

LEAF SPOT (Cercospora atro-marginalis Atk.) was observed
on the host in waste places. It destroyed the leaves, but was of
no economic consequence.
ANTHRACNOSE (Gloeosporium quercinum West.) caused con-
siderable spotting of leaves, some of which were shed, but its
damage was not serious.
LEAF SPOT (Taphrina coerulescens (D. & M.) Tul.) caused
considerable damage to water oaks in Pensacola and St. Augus-
tine. Large trees were almost completely defoliated; the situa-
tion was indeed alarming. It was collected in Gainesville. It
was not of a serious nature.
LEAF SPOT (Helminthosporium avenue Ei.) was serious in the
test plots, killing many plants. Twenty percent of the seedlings
killed were January plantings.
LOOSE SMUT (Ustilago avenue (Pers.) Jens.) was collected
during March and April in central Florida. The disease in no
case included more than 1 percent of the heads.
CROWN RUST (Puccinia coronta Cda.) was the most important
disease of oats in Florida. It was collected first in January and
the infections soon were killing the plants. Distribution was
wide and of a general nature. The disease was destructive until
after May when all oats were harvested. Some species of oats
were affected so badly that they were killed completely before
they could head out; others developed a few scattered heads.
ANTHRACNOSE (Colletotrichum sp.) was reported from Pan-
ama City, causing minor damage.
DAMPING-OFF (Rhizoctonia sp.) caused considerable loss to
truckers and gardeners. These attacks were supplemented by
unusual rains.
WILT (Fusarium vasinfectum Atk.) was reported from the
vicinity of Gainesville as doing considerable. damage to half-
grown plants. Local infections on the leaves were also noted.
LEAF SPOT (Phyllosticta sp.) was collected, causing large,
brown spots on leaves, which caused some defoliation.


Annual Report, 1923

SPECKLED LEAF SPOT (Septoria sp.) caused some defoliation
but not of a serious nature.

LEAF SPOT (Botrytis cinerea Pers.) was found causing consid-
erable damages to half an acre of onions near Gainesville. It
killed practically all foliage in a short time.
BLACK MOLD (Macrosporium sp.) was common wherever on-
ions grew, attacking the upper parts of the leaves before the
seed stalks were fully grown. It caused slight damage altho
100 percent infections were common.

LEAF SPOT (Diplodia sp.) caused considerable loss of foliage at
Palm Beach.

RUST (Uredo oxalidis Lev.) was collected at Micanopy and
Gainesville in February, and at Oneco in May. The fungus
caused 100 percent infection, killing all the foliage in two or
three weeks.
PALM (Phoenix)
LEAF BLIGHT (Exosporium palmivorum Sacc.) caused serious
losses to these plants in Florida. The disease was reported from
the whole state in general. It was especially severe in nurseries
and along the east coast. In many instances total defoliation
and destruction of the plant was reported. It was widespread
but not destructive in the state as a whole.
LEAF SPOT (Ramularia sp.) was found at Gainesville in Sep-
tember, but was of no economic importance.
PALM (Washingtonia)
LEAF SPOT (Pestalozzia palmicola S. & S.) was destructive to
the leaves in Gainesville, beginning at the tips of the leaves, grad-
ually working toward the petiole, killing the tissue and turning
it brown. It was serious on ornamental plants.
BACTERIAL LEAF SPOT (Bacterial sp.) was collected at Tampa,
causing death of leaves on several plants. It was not common.
LEAF SPOT (Graphiola phoenicis (Moreg.) Poit) was common
on the host plant in the state.


Florida Agricultural Experiment Station

BLOTCH (Pestalozzia palmicola S. & S.) was common in the
state, often causing partial defoliation.
LEAF SPOT (Pucciniopsis caricae Earle), collected in numerous
places in Florida, was a serious leaf disease. Defoliation re-
sulted from severe infections. As this plant is not extensively
grown, the economic loss is small.
ROT (Bacillus caratovorous Jones) was found in a garden in
Gainesville, 90 percent of the plants being affected and even-
tually killed. It was not common.
PEA (English)
DAMPING-OFF (Pythium de baryanum Hesse) caused consid-
erable damage near Palm Beach and Interlachen. The loss in
a field near Micanopy amounted to 90 percent of the stand.
DOWNY MILDEW (Peronospora viciae Berk.) was collected
near Micanopy, where it was widespread. Ninety percent of the
plants were infected on the first two leaves when the plants were
six inches high on February 12. The severe freeze of February
19 killed them so that estimates of loss from the fungus were
BLACK MOLD (Alternaria vitis Cav.) was a serious disease near
Gainesville where 60 percent of the pods and from 90 to 100
percent of the vines were attacked. It finally killed the vines,
causing a 20 percent loss in this instance.
POWDERY MILDEW (Erysiphe pologone D. C.) was by far the
worst disease of the host in Florida. Near Micanopy two fields
of 10 and 23 acres, respectively, resulted in a 70 percent loss.
Other smaller scattered fields suffered similar losses. Dusting
experiments with sulphur were started in an attempt to control
the disease in some late-planted fields, but soon after the second
application of sulphur the plants were completely destroyed by
frost on February 19.
FROSTY MILDEW (Cercosporella persicae Sacc.) was collected
near Quincy. No damage was reported.
GUMMOSIS (not known) was collected near Moss Bluff, caus-
ing the destruction' of most of the branches of several three-
and four-year-old trees.


Annual Report, 1923

RUST (Franzschelia punctata (Pers.) Arth.) was collected
during January, February, and March and was found to be
widespread and, at that time, serious, since it caused complete
defoliation. It is probably of little economic importance.
SHOT-HOLE (Cercospora circumscissa Sacc.), collected at
Gainesville, caused little damage since the fruit had already
been picked.

LEAF SPOT (Cercospora personata (B. & C.) E.) was the most
important disease of peanuts in Florida. The infection was
found when the plants were a few inches high. It continued in
severity until the plants were mature, when they were three-
fourths defoliated.
WILT (Fusarium sp.) was found causing some loss in fields
near Gainesville; not serious.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was collected near
Gainesville, causing about 1 percent loss of plants in several
fields. It girdled the stems at the surface of the soil, causing
them to die. It was especially serious following wet weather.

FIRE BLIGHT (Bacillus amylovorus (Burr.) Trev.) was re-
ported from several different points in the state. At Gainesville
several trees were almost killed by it. Numerous older groves
were abandoned. It is considered the controlling factor in
growing pears in the state.
HYPOCHNUS (Corticium stevensii (Noock.) Burt), reported
only from Gainesville, was destructive on a half dozen old trees.
The disease was first noted in May, later it spread rapidly, at-
tacking the twigs and leaves. The leaves were rapidly killed and:
turned black, clinging to the tree as in fire blight. Fifty-percent
defoliation is noted at this time, Mycelial strands and sclerotia
are plentiful.
TWIG BLIGHT (Phoma amligna (Nitz.) Sacc.) was collected at
Bristol evidently killing twigs and small branches; not serious.
FELTY FUNGUS (Septobasidium pedicillata (Schw.) Pat.) was
found on twigs and small branches of the host plant apparently
causing no damage, altho it was plentiful.
Another closely related species, Telephora retaformis, was de-
tected on pear trees at Pensacola; it was plentiful but little dam-
age was evident.


Florida Agricultural Experiment Station

ANTHRACNOSE (Glomerella cingulata (Sto.) S. & S.) was re-
ported from pecan areas during August and September. It was
evidently widespread; however, serious losses were not reported.
BLIGHT (Bacterial sp.) caused some uneasiness because of
twigs killed. It was not serious, however.
LEAF BLOTCH (Cercospora fusca Rand) was found to be com-
mon and widespread, causing partial defoliation in certain in-
COLD INJURY, caused probably by weather conditions, was re-
ported frequently but only scattered trees were affected. It
proved serious rarely.
DIEBACK (Botryosphaeria berengeriana Demot.) was found
somewhat scattered at Green Cove Springs. Nothing serious
was reported.
TWIG BLIGHT (cause unknown) was more or less common and
in several instances species of Fusarium were isolated from the
LEAF SPOT (Lichenes sp.) was common during the year. The
resulting damage was merely a small loss of leaf area, leading to
a slight shedding of leaves.
POWDERY MILDEW (Microsphaera alni (Wallr.) Wint.) was re-
ported common in the vicinity of Pensacola.
SCAB (Fusicladium effusum Wint.) was the most serious dis-
ease of the host plant. It was reported common wherever pecans
were grown and in many instances was of economic importance.
Control methods are not practiced in many groves.
NURSERY BLIGHT (Phyllosticta caryae Pk.) was common and
frequently serious, causing in one nursery almost complete de-
foliation. In general, it was not considered serious as young
trees were most often attacked.
PINK MOLD .(Cephalothecium roseum Cda.) was found,
often being closely associated with scab. In all cases observed it
appeared to be secondary, the principal losses being attributed to
RUST (Puccinia hydrocotyles (Mont.) Cke.) was collected on
this plant in scattered places in the state. It was common.
ANTHRACNOSE (Colletotrichum nigrum Ell. & Hals.), last
season, was a serious disease, occurring wherever peppers


Annual Report, 1923

were grown and causing a 2-percent loss thruout the state. It
was especially serious in the Sanford district.
BACTECIAL LEAF SPOT (Bacterium vesicatorium Doige) was
destructive to pepper plants in Gainesville. One garden of 800
plants was almost entirely defoliated. Most of the plants were
killed. It was not common, however.
LEAF SPOT (Cercospora capsici Heald & Wolf) was reported
from practically all parts of the state and was collected every
month of the year. It was common but only in a few instances
did it prove of serious consequences. It caused a loss of about
3 percent.
DAMPING-OFF (Rhizoctonia solani Kuhn.) proved to be the
worst trouble in growing peppers. Reports were received of
the seriousness of the disease and also its prevalence, A 5-per-
cent reduction of seedbed stands was estimated.
WILT (Fusarium sp.) was not common in the state. It was
reported serious from the vicinity of Wauchula.
FRUIT SPOT (Gloeosporium piperatum Ell. & Ev.) was common
near Gainesville. It caused a 4-percent loss to fruit in that
immediate vicinity.
BLACK MOLD (Macrosporium commune Rab.) proved to be the
worst disease of pepper last season. All fungous attacks injured
fruit, gaining entrance thru mechanical, insect and sunburn
injuries. In many fields 60 percent of the fruit was unmarket-
able.. Estimated losses of 10 percent were attributed to this
DOWNY MILDEW (Peronospora parasitica (Pers.) DeBary)
was collected on this host in Gainesville, the flat bordering on a
cabbage patch badly infected. The disease was plentiful and
disastrous on this host.
ANTHRACNOSE (Colletotrichum sp.) caused considerable twig
blight. It was common but not serious. Caused partial defolia-
tion of several trees near Gainesville.
TWIG BLIGHT (Phoma disopyri Sacc.) was reported from
Jacksonville, causing minor injury.
LEAF SPOT (Pestalozzia guepini Desm.) was found to be the
causal agent of considerable defoliation and some fruit spots.
ROSETTE (cause unknown) was reported from Brooksville,
being found frequently.


92R Florida Agricultural Experiment Station

.. ANTHRACNOSE (Colletotrichum sp.) was found causing canker-
,like lesions on the stems; local and not serious.,
WHITE RUST (Albugo bliti (Biv.) Kze.) was collected at Vero
and at Gainesville. It caused partial defoliation of the host.
RUST (Coleosporium vernoniae B. & C.) was plentiful on young
trees up to eight feet tall, infecting 90 percent of the leaves;
Pittosporum sp.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was collected at
Jacksonville, causing considerable damage to the host plants.
Not common or widespread.

LEAF SPOT (Bacterium pruni E. F. S.) was collected frequently
near Gainesville. The leaves were attacked severely and some
defoliation resulted. It was collected also at Jacksonville.
SHOT HOLE (Cylindrosporium padi Karst.) was destructive to
both wild and cultivated plants in the vicinity of Gainesville.
The leaves were severely shot-holed and 40 percent of them were
TWIG BLIGHT (Diplodia pruni Fckl.) was found commonly on
the host plant and in scattered instances was of a serious na-
ture on young trees.
PLUM POCKET (Exoascus p'runi (Berk.) Fckl.) was collected
on the wild plum in the vicinity of Gainesville. All trees in-
spected were affected 100 percent, no fruit maturing unattacked.
POWDERY MILDEW (Podosphaera oxyacanthae (D. C.) de By.)
was common and destructive, altho not widespread. The new
growth was particularly attacked, including the leaves and green
stems as they developed.
FELTY FUNGUS (Septobasidium pedicillata (Schw.) Pat.) was
collected near Gainesville. It was plentiful in the infested trees
but was apparently doing little damage. Another species, Tele-
phora retaformis, was collected at Green Cove Springs and Pa-
latka. In no instance was it reported of serious consequence,
altho it was prevalent.

Annual Report, 1923

ANTHRACNOSE (Gloeosporium sp.) was reported from Braden-
town as causing slight damage; not common.

TWIG BLIGHT (Bacterium sp.) caused considerable apprehen-
sion last season, killing twigs and new vigorous growth. It was
not serious.
WILT (Fusarium sp.), found quite common near Gainesville,
usually killed the best plant. The leaves turned yellow and
fell. The newest leaves were shed last and the plants usually
MOSAIC (cause unknown) was found on the host plant practi-
cally everywhere in the state. The host is widely scattered and
was found to be 100 percent infected, whether isolated in thick
woods or growing on the border of cultivated fields.
LEAF SPOT (Cercosporella sp.) was collected on the host at
Gainesville, killing the leaves at blossoming time.
ANTHRACNOSE (Vermicularia albo-atrum, Reink. & Berth.)
was collected on two occasions only, in the vicinity of Hastings,
on potato stems. It was not common.
BACTERIAL WILT (Bacillus solanacearum E. F. S.) was prev-
alent in the potato areas of the state. It assumed serious pro-
portions in 50 percent of the fields. A 20-acre field near Fed-
eral Point showed 40 percent infection with a 10 percent reduc-
tion in yield. Another 60-acre field near Hastings showed from
12 to 15 percent reduction in yield. From 3 to 5 percent would
cover the losses in the state.
BLACK LEG (Bacillus phytophthorus Appel) was common in
all potato fields in the state. It was widespread but no fields
suffered seriously. A field near Hastings showed a 50 percent
infection resulting in a 10 percent loss. The losses attributed
to this disease would not exceed 1 percent.
CURLY DWARF (cause unknown) was found in practically
every potato field in the Hastings district. The plants were de-
cidedly dwarfed and the loss in yield paralleled infected plants.


Florida Agricultural Experiment Station

A 60-acre field at Federal Point showed a 10 percent loss fron
this cause. The loss for the district would not exceed 2 percent
EARLY BLIGHT (Alternaria solani (E. & M.) J. & G.) assume(
serious proportions during the latter part of the season (Marcl
and April). As soon as the warm weather began the disease
spread rapidly. Most of the potatoes were approaching matur
ity at the time so that little loss resulted from the disease, ever
tho practically all fields showed the plants were 100 percent in
FUSARIUM WILT (Fusarium sp.) was scarce; losses from ii
were of no consequence.
LATE BLIGHT (Phytophthora infestans (Mont.) de By.) : Th(
first outbreak of late blight was observed at Federal Point or
February 20, at that time the disease had covered two areas
each about fifty feet in diameter, in the same field. It was cal.
culated the disease had been spreading from two original in.
fections for about two weeks. The usual typical symptoms were
evident, but more virulent in every way than generally consid.
ered for this blight. The sporulating areas on the leaves wer<
conspicuous and the infections on the petioles and stems of the
plants were indeed vigorous and destructive. The main stalks
of the plants were all that were left standing in the centers oJ
these infected areas. This field was visited ten days later anc
the whole ten acres was completely dead and brown, only the
main stems were standing. Blight was found in 14 fields
around Federal Point during the next two weeks. On March 1(
a single field near East Palatka was found infected in several:
small areas. The disease was not serious in this field at this
time but later caused serious losses. During the latter part oJ
March and first part of April it spread extensively and by the
middle of April was quite generally distributed. However, the
real damage to the crop was done in the isolated fields before
the disease became so widespread. The temperature increase
considerably after the first of March and the fungus was checked
in its ravages. In fact, after the middle of March the disease
areas on the leaves were in the form of small spots rather thar
large, irregular blotches involving the whole leaf as it did a
month earlier. The white, downy, sporulating areas disappeared
and the fruiting fungus was difficult to find except in the earls
morning before the plants were dry of dew. It was also noted
that the stems and petioles were entirely free from infections
The warmer weather had almost checked the disease as far as


Annual Report, 1923

its doing material damage to the crop was concerned. By the
middle of April most potato fields had been planted for from 90
to 100 days, which is the usual length of the growing season, so
that the disease was not a serious factor.
MOSAIC (cause unknown) was common and well-distributed
in potato fields with one exception. There was not found more
than 15 percent diseased plants in any field. A single field of
Bliss Triumph showed from 90 to 95 percent of infected plants
in which field the yield was naturally reduced. Losses from this
disease averaged from 1 to 2 percent.
STEM BLIGHT (Rhizoctonia solani Kuhn.) was not serious,
altho it was widespread in the potato district. Loss from this
disease was less than 1 percent.
SCAB (Actinomyces scabies (Thax.) Guss.) was collected fre-
quently at ports by quarantine inspectors. The disease also was
found near Hastings in scattered fields. The loss resulting was
SILVER SCURF (Spondylocladium atroviens Hanz.) was col-
lected on seed potatoes shipped to Florida from Maine, New
York and Minnesota. The disease was of little importance in
the state last season.
YELLOW WILT (Sclerotinia libertiana Fckl.) was found in a
few scattered fields where it was not widespread. The losses
resulting were of no economic importance.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was common and
well-scattered over the whole potato area. The disease in no
case assumed the proportions of an epidemic, altho severe losses
were noted in certain fields. This disease was one of the most
important during the growing season and resulted in a loss of
from 5 to 7 percent.
TUBER ROT (Fusarium oxysporum Schelcht.) resulted in ser-
ious losses to growers because of the decay of seed. Most
farmers suffered losses from this cause. The percentage of
seed tubers cast aside because of this disease ranged from none
(a few brands of certified seed) to 35 percent (brands of com-
mon seed).
WEAK SEED (cause unknown) was the cause of a decided re-
duction of stand in fields following the freeze of February 19.
In many fields a 20 percent reduction of stand was attributed to
the failure of the seed piece (due to lack of potential) to send up
a second sprout to replace the one frozen off at the surface of the


Florida Agricultural Experiment Station

ANTHRACNOSE (Gloeosporium venctum Speg.) was common on
wild varieties and reported as somewhat destrutcive on culti-
vated plants near Tallahassee.
SESAME SPOT (Helminthosporium oryzae B. de H.) was col-
lected at Gainesville where 'it showed 100 percent infection on
a small patch. A portion was completely killed before it was
eight inches tall.
SOFT ROT (Sclerotinia libertinia Fckl.) was common and well-
scattered in the trucking districts. This was practically the only
disease attacking the host and which caused a loss of from 5 to
10 percent in the fields.
ANTHRACNOSE (Gloeosprium rosae Hals.) was sent in for in-
quiry as to control methods from several points in the state. It
apparently was well scattered but not of a serious consequence.
BLIGHT (Dicoccum rosae Bon.) was found but once in -the
state, causing slight injury.
LEAF BLOTCH (Pestalozzia compact Sacc.) caused consider-
able defoliation to the host plants in different parts of the state.
It was well scattered but not severe.
POWDERY MILDEW (Sphaerotheca pannosa (Wallr.) Lev.) was
serious because of its persistence and the consequent defoliation
of the host plants. It was state-wide and often caused complete
LEAF SPOT (Cercospora rosicola Pass.) was almost universally
present where roses were grown. It ranked next to powdery
mildew in importance.
ANTHRACNOSE (Colletotrichum sp.) was reported from Vero
as destructive to several plants.
LEAF SPOT (Phyllochora ficunm Niessl.) was found on the
host in the vicinity of Palm Beach where the spots covered two-
thinds of the leaf surface. It was not reported widespread.

96R .

Annual Report, 1923

TWIG BLIGHT (Phoma atro-cincta Sacc.) was found doing
minor injury to trees near Rosedale and Oneco.

POWDERY MILDEW (Oidium balsamii Mont.) was found on the
host wherever grown and in certain instances caused the total
loss of the plants.
DOWNY MILDEW (Peronospora parasitica (Pers.) de By.) was
collected on the host plant at Gainesville.
LEAF RUST (Puccinia disperse Eriks.) was rather common on
rye in the vicinity of Gainesville. All leaves were dead at head-
ing. time.
RUST (Puccinia smilacis Schw.) was collected in February at
several different points in the state. It was common but not
LEAF SPOT (Cercospora longipes Butler) caused considerable
loss of leaf area in a field near Gainesville. The leaves were
three-fourths killed soon after blossoming time.
RUST (Puccinia purpurea C.) was found at Vero and Gaines-
ville on the host plant; no damage resulted.
DOWNY MILDEW (Pseudoperonospora cubensis (Bri. & Cav.)
Humply) was the cause of the premature death of plants in gar-
dens at Gainesville.
MOSAIC (cause unknown) was serious near Gainesville and
cut off production by 50 percent. Its range in the state was not
.WILT (Fusarium sp.) caused some loss of plants early in the
season near Plant City.
PURPLE LEAF SPOT (Mycosphaerella fragariae (Tul.) Lindau)
was rather common in the vicinity of Plant City. No serious re-
sults were noted.
LEAF BLOTCH (Pestalozzia guepini Desm.) was common on
strawberry leaves, killing them from the margins.


Florida Agricultural Experiment Station

LEAF SPOT (Phyllosticta fragaricola D. & Rab.) was reported
frequently from Plant City and Kissimmee. It was important
because of the reduction of foliage it caused.
LEAF BLIGHT (Ramularia tulasnei Sacc.) was collected once at
Plant City where it did slight damage.
RED ROT (Colletotrichum fulcatum Went.) was common on
cane last season, especially in western Florida. It was wide-
spread and losses were large.
RUST (Puccinia helianthi Schw.) was collected at Palm Beach.
It was common but not serious.
WILT (Futsarium vasinfectum Atk.) was reported as causing
the loss of 5 percent of the sweet peas in several gardens.
ANTHRACNOSE (Glomerella rufomaculans (Berk.) S. & V.
Sch.) was reported from Tampa as causing many spots on
leaves. It was also reported from Quincy.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) caused the wilting
and death of the host plant at and near St. Augustine.
BLACK ROT (Sphaeronema fimbriatum (E. & H.) Sacc.) was
found but once in the state. The collection was made near Talla-
hassee. It was not plentiful and was of no economic importance.
SCURF (Monilochaetes infuscans Hals.) was widely scattered
but in no case did it prove of economic importance.
LEAF SPOT (Cercospora batatae Zimm.) was found in scattered
places where the host plant was grown. In no case was the dis-
ease observed to be serious.
WET MOLD (Chaenophora sp.) was observed killing a large
number of leaves. It was found especially active in the morn-
ings; not important.
WILT (Fusarium batatis Woll.) was exceptionally scarce last
season, being collected in only two instances in the state but.
even then it was causing no damage.
SPECKLED LEAF SPOT (Phyllosticta batatas Cke.) was collected
from every sweet potato field inspected. It was common and
widespread but little damage resulted from it.
Pox (Cystospora batata Elliott) was found only in the vicinity


Annual Report, 1923

of Orlando, Eustis and Gainesville. The infections were few
and the economic loss was of no consequence.
DAMPING-OFF (Rhizoctonia sp.) caused considerable damage in
seedbeds, where it destroyed the usefulness of draws.
SOFT ROT (Rhizopus nigricans Ebr.) was one of the worst
storage diseases of Florida. The fungus entered the tubers
wherever injured, and resulted in a loss of 1 percent.
RUST (Albugo ipomoeae-panduranae (Schw.) Swingle) was
common and widespread but of no economic importance.
MOSAIC (cause unknown), was observed in a ten-acre field near
Gainesville where an actual count showed that 6 percent of the
plants were affected, 5 percent of them being lost in the field.
It was not noted elsewhere in the state.
JAVA BLACK ROT (Diplodia tubericola (E. & E.) Taub.) was
a serious storage disease. It was reported as attacking tubers
in all parts of the state. It caused a loss from 5 to 10 percent.
SOUTHERN WILT (Sclerotium rolfsii Sacc.) was collected in the
vicinity of Gainesville. The fungus girdled the stems, causing
some damage. It was not well distributed or of a serious nature.
CHARCOAL ROT (Sclerotium bataticola Taub.) was prevalent
in storage, causing a loss of from 2 to 4 percent. It was one
of the most important diseases of sweet potatoes in storage.

BACTERIAL WILT (Bacillus solanacearum E. F. S.) was serious
wherever tomatoes were grown. Plants were killed in all stages
of growth, most frequently, however, just before blossoming
time. The stand was reduced 2 percent. Few affected plants
developed marketable fruit. It was reported from Tavernier
Florida Keys in January and along the east coast soon after-
ward. It was destructive in the vicinity of Pensacola in May
and June. i
LEAF MOLD (Cladosporium fulvum Cke.) was collected in 5
percent of the tomato fields visited in different parts of the
state. In most fields 100 percent of the plants were affected but
the damage was comparatively light.
ANTHRACNOSE (Colletotrichum phomoides (Sacc.) Chester)
was recorded several times in the state but was not of a serious
nature. Losses were negligible.
EARLY BLIGHT (Macrosporium solani E. & M.) was by far the
most important of the diseases of tomatoes in Florida. This dis-
ease was found in all parts of the state and almost without ex-


Florida Agricultural Experiment Station

ception it proved disastrous to crops. It was first reported from
the Florida Keys in December and early January. It spread up
the state until the end of the tomato season in May. December
infections caused the least loss. The disease was the most ser-
ious along the east coast north of Palm Beach. A field of 120
acres near Hobe Sound was a total loss; the few crates picked
did not pay for the seed planted, to say nothing of cultivation,
rent, and $40 an acre for fertilizer. This was only an example of
the condition of hundreds of other farms in that vicinity. A well-
informed grower estimated that the loss suffered by growers
who shipped from Vero would exceed $100,000. A conservative
estimate for the state would place the loss at about a million
dollars. Nowhere did the crop average 50 percent. There were
scattered fields, some quite extensive, that marketed from 80 to
90 percent of the crop but these were exceptions.
FUSARIUM WILT (Fusarium lycopersici Sacc.) was found ser-
ious only in localities near Bradentown. Several fields were
badly infected, certain spots an acre or two in extent returning
total losses. The disease was generally well scattered and ex-
cept for the instances noted above, no serious losses were found
resulting from this disease. Certain fields near Sebastian showed
an infection of 10 percent.
FRUIT SOFT ROT (Rhizopus nigricans Ehrb.) was well distrib-
uted over the state. It was especially prevalent on the fruit
where insects had not been controlled, gaining entrance thru
wounds made by the ants.
LEAF SPOT (Gloeosporium phyllochoroides Ell. & Ev.) was re-
ported from Tavernier. It was of no importance.
LEAF SPOT (Septoria lycopersici Speg.) developed on tomato
plants after March. Late in the tomato season plants showed a
100 percent infection. However, the losses attributed to this
disease were small.
MOSAIC (cause unknown) was well distributed in tomato fields.
In no place was there recorded a severe epidemic. A 40-acre
field near Vero showed 10 percent of the plants were diseased.
Another 18-acre field near Sanford showed an infection of from
4 to 6 percent. The loss for the state would not exceed .5 percent.
STEM BLIGHT (Phoma destructive Plowr.) was found near
Bradentown doing slight damage.
WATERY SOFT ROT (Sclerotinia libertiana Fckl.) was found at
Sanford doing minor injury to large, spreading vines dense with


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