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/UF00005173/00013
 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: 1914
Copyright Date: 1905
Frequency: annual
Subject: Agriculture -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
Dates or Sequential Designation: 1905-1930.
Statement of Responsibility: Florida Agricultural Experiment Station.
 Record Information
Bibliographic ID: UF00005173
Volume ID: VID00013
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 i
        Page ii
    Table of Contents
        Page iii
        Page iv
        Page v
        Page vi
    Letter of transmittal
        Page vii
    Board of control and station staff
        Page viii
        Page ix
        Page x
        Page xi
        Page xii
        Page xiii
        Page xiv
        Page xv
        Page xvi
        Page xvii
        Page xviii
        Page xix
        Page xx
        Page xxi
        Page xxii
        Page xxiii
        Page xxiv
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        Page xxvii
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        Page xxx
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        Page lxxxv
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        Page xc
        Page xci
        Page xcii
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        Page xcv
        Page xcvi
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        Page xcix
        Page c
        Page ci
        Page cii
        Page ciii
        Page civ
        Page cv
        Page cvi
        Page cvii
        Page cviii
        Index 1
        Index 2
        Index 3
        Index 4
        Index 5
        Index 6
        Index 7
        Index 8
        Index 9
        Index 10
Full Text





APRIL, 1915.


BOARD OF CONTROL ---------------- ------------------------------- iii
EXPERIMENT STATION STAFF -------------.------.....----------.----. Viii
Introduction -_------.------....-------- xi
Lines of Work ------ _. ...._---- ---------------------- xii
Publications ----..-------------------------------------- xvi
REPORT OF AUDITOR ---..--....... ..---- ------------- _------_--_- XVii
REPORT OF ANIMAL INDUSTRIALIST ----- ------------------------ xviii
Dairy Herd -------.........---- -------------------- xviii
Hogs ------------------- ----------------------------- xix
Pig-feeding Experiments --------------------------------------- xix
Soudan Grass --------------------------------- ----- ----- xxii
Teff ------ --_ ----------------------- xxiii
Japanese Cane -------------------------------------- xxiii
Comparative Yield Test of New Beans ------- -------- xxvi
Soybeans and Cowpeas ----- ------------------- ----- xxvii
Sweet Potatoes ------ ------- ------------------ -- xxviii
Chinese Velvet Beans ------------ ------------ -----xxviii
Kudzu _. ...-------------------------------------- xxix
REPORT OF PLANT PHYSIOLOGIST -------------------_--------------_ xxx
Water-table Experiment .-- ---------_---------------------_ xxx
Pot Experiments with Citrus Seedlings -- ----------------xxxv
Sand Cultures with Citrus Seedlings ----- ------ -------- xxxviii
REPORT OF ENTOMOLOGIST ------------------------------------------ xlvi
The Wooly Whitefly ---.--------.... --------------- ------ xlvi
Entomogenous Fungi ..---------- ------------------------__ xlvi
The Use of Sprays Against the Caterpillar of Velvet Beans --- 1
Heliothis obsoleta on Tomatoes ---------------- -------- liii
Spread of the Cottony-cushion Scale -------------------------- lv
Miscellaneous Insects ------------------------------------- Iv
REPORT OF PLANT PATHOLOGIST ----- -----------_ -------_ Ivii
Gummosis --... -------_ --------------------------- lvii
Melanose ..-----------x----------------------------_ lxi
Citrus Canker --- ------------- ----------------------- lxxiii
REPORT OF CHEMIST ___------------ ---------------------- __ ---- Ixxv
Citrus Experimental Grove ---------------------------------- Ixxv
Soil Tank Experiments .---.__------_-------------------__ Ixxvii
Miscellaneous Work ----.----.-- -----------------__ ---__-- lxxx
REPORT OF ASSISTANT BOTANIST -------------------------------------_ Ilxxxi
Breeding Work of the Year ------ --------------------- I_ xxxi
Increase of Growth on Crossing --------------------------------_ lxxxiv
Inheritance of- Pubescence of Pods and Plants ---- ----- lxxxv
Inheritance of Partial Sterility ---- ------------------ xcvi
Corn Crosses ------------------ ---------------------------- cvi

iv Contents

Introduction _--_------- ---------------------------------- 3
Navel 6----------------------------------- 6
Parson Brown ------------------------------------- ---- 6
Pineapple ---------------------------------------- 8
Valencia --- -- -------------- ---------------------- 9
Miscellaneous named oranges -------------------------------------- 9
Seedlings .---------- --------------------------- --- Ii
Tangerine and Satsuma -------------------------------------- -- 18
Silver Cluster ------------- -------------------------- 18
Marsh --------------------------------------------- ---- 20
Triumph -- ----------------------------------------------- 21
Miscellaneous named grapefruit ----------------------------------- 21
Budded -------------------------------------------------- 21
Common ---------------------------------------- 22

Introduction ---------------------------------------- 27
Description ---------------------------------- 27
History ---------------------------------------- 27
Infection in the Seed Beds ------------------ ---------- ----- 28
The Fungus ---------------------------------------- 28
Growth of Fungus --------------------------------- ---- --- 29
Development of Apothecia ------------------------------------- -- 30
Infection Experiments ----------------------------------- -- --- 31
Other Plants Affected --------------------------------------- 32
Treatment ------------------------------------------------ 32

Rust ------------------------------------------------ 37
Fungus Blight ---------------------------------------- 38
Sclerotium Blight ------------------------------- --- ---- 40
Bacterial Blight, Wilts -------------------------------------- -- 42
Dropping of Bloom Buds --------------------------------------- 44
Leaf Curl, or Roll Leaf ------------------------------------ --- 45
Damping Off --------------------------------- ------- 45
Hollow Stem ---------------------------------------- 47
Scab, Black Spot -------------------------------------- 47
Blossom-End Rot --------------------------------------- 48

Introduction -------------------------------------------- 51
Soil ------------------------------------- 51
Soil Preparation ---- ----------------------------------------- 52
Rotation --------------------------------------- --- ------ 53
Fertilizers ----------------- -------------------------- 53
Planting ------------------------------------------------ 54
Cultivation ------------------------------------------------------- 55
Harvesting ------------------------------------ ------ 55
Seed-Cane ------------------- ------ ------------------ 56

Contents v
Time to Save Seed-Cane -------------------------------------- 56
Laying Down the Bed ------------------------------------- -- 57
Stubble or Ratoon Cane ------------------------------------- -- 58
Varieties ------- -------------- ------------------------58
Japanese Cane ------------------------------------- --- 59
Cane Grinding -------------------------------------------------------59
Evaporation of Juice ------------------------------- -60
Fermentation in Syrup ------------------------------------- 64
Diseases of Sugar Cane --------------------------------------- 65
Red Rot --------------------------------------- 65
Insect Enemies of Sugar-Cane ------------------------------------ 66
The Cane Borer ------------------------------------ --66
The Army Worm --------- ------------------------------ 67
Danger in Imported Canes ---------------- -------------------- 67

Favorable Conditions in Florida ----------------------------------- 71
These Fungi Do Not Attack Trees --- --------------------------------71
Care Necessary for Success -------------------------------------- 72
Time Necessary to Secure Infection ------------------------------- 73
The Experiment Station Cannot Supply Fungi ------------------------73
Where Fungi May Be Bought ---------------------------------73
The Red-Headed Fungus ---------------------------------------- 74
Species of Scale Insects Infected --------------------------------74
How to Apply the Fungus ----------------------------------- 75
The White-Headed Fungus ----------------------------------------- 75
How to Apply the Fungus ------------------------------------ 76
Species of Insects Infected ---------------- ------------------- 77
The Black Fungus ----------------------------------------- 78
Scale Insects Attacked -------------------- --------------- -- 78
How to Apply the Fungus ---------------- ------------------ -79
The Red Fungus of the Whitefly ------------- ------------------ 79
How to Apply the Fungus ----------------- ----------------- -- 80
The Yellow Fungus of the Whitefly ------------------------------- 81
How to Apply the Fungus -- ---------------------------------- 81
The Brown Fungus of the Whitefly --------------- -----------------81
How to Apply the Fungus ------------------------------------- 82
The Cinnamon Fungus --------------------------------------- 82
How to Apply the Fungus ----------------- ------------------- 82

Introduction -------- ------------------------------ -------- 85
Soils ------- ----------------------------------------------------- 85
Preparation of the Soil --------------------------------- ------- 86
Fertilization ----------------- -------------------------- -- 86
Planting --------------------------------------------------------- 88
Winter Planting .--------------------------------------- 89
Fall Planting ----------- -------- ------------------------ 89
Seed Potatoes ------------------------------------------ 90
Varieties ------------------ -------------------------- 90
Causes of Imperfect Stands ------------------------------------ -- 90
Cultivation -------------- ------------------------------------ 91
Harvesting -------...... ------------------------------- -- 92

vi Contents
Marketing -------------------------------------------------------- 92
Rotation ------------------------------------------------- ------- 92
Irrigation ------------------- -------------------------------- 93

Introduction ------------------ ----------------------------- ---- 97
Character of the Disease --------------------------------------- 98
Fruit Infection ---------------------------------------- 98
Cause of the Disease --------------------- ------------------- 0I
Isolation of Bacteria ------------------------------------- --- o
Preliminary Tests ---------------------------------------- 102
Inoculations ---------------------------------------- 102
The Bacillus ---------------------------------------- 104
Spraying Experiments ----------- --------------------- ---- 105
Irrigation ----------------------------------------- 1o6
Nitrate of Soda ------------------------------------- ---- o6
Picking and Packing the Fruit ---------------------------------- 107
Control ----------------------------------------------- o8
Bordeaux Mixture ----------------------------------------- o8

Introduction ------------------- ---------------- 113
Nature of the Disease ---------------------------------------- 113
Appearance ------------- ---------------------- 114
Distinction from Other Diseases ---------- ------------ --------- 115
Cause of the Disease ---------------------------- ---- --------- 117
Control ------- -- ----------- -- ------------------------117


215.-Harvesting Corn.
Fodder pulling.
Starting the shock.
Feeding value of corn stover.
216.-Spraying for the Velvet Bean
Natural enemies.
217.-Preserving Fungus Parasites of
218.-Bulletins and Reports on Hand.
219.-Sorghum for Hog Pasture.
Pasturing the crop.

220.-Cowpeas for Hog Pasture.
221.-Cucumber and Cantaloupe Blight.
Symptoms of the disease.
Preventive measures.
Spraying for blight.
Cause of the disease.
Control measures.
Great loss possible this year.
223.-Bulletins and Reports on Hand.
224.-Cottony Cushion Scale.


Hon. Park Trammell,
Governor of Florida,
Tallahassee, Fla.
SIR: I have the honor to transmit herewith the annual report
of the Director of the Florida Experiment Station,-for the fiscal
year end4ig June 30, 1914.
Chairman of the Board of Control.

P. K. YONGE, Chairman, Pensacola, Fla.
T. B. KING, Arcadia, Fla.
E. L. WARTMANN, Citra, Fla.
F. E. JENNINGS, Jacksonville, Fla.
W. D. FINLAYSON, Old Town, Fla.

P. H. ROLFS, M.S., Director.
J. M. SCOTT, B.S., Animal Industrialist, and Assistant Director.
B. F. FLOYD, A.M., Plant Physiologist.
J. R. WATSON, A.M., Entomologist.
H:.E. STEVENS, M.S., Plant Pathologist.
S. E. COLLISION, MS., Chemist.
JOHN BELLING, B.Sc., Assistant Botanist, and Editor.
S. S. WALKER, M.S., Assistant Chemist.
JOHN SCHNABEL, Assistant Horticulturist.
EDGAR NELSON, A.B., Assistant Plant Physiologist.*
A. C. MASON, B.S., Laboratory Assistant in Entomology.
JULIUS MATZ, B.S., Laboratory Assistant in Plant Pathology.
H. G. CLAYTON, B.S.A., Laboratory Assistant in Animal In-
T. VAN HYNING, Librarian.
K. H. GRAHAM, Auditor and Bookkeeper.
E. G. SHAW, Secretary.
ML CREWS, Farm Foreman.
*Temporarily employed.


FIG. I.-Chinese velvet bean.

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L~ I~;iC~

j~ ~I.

.-., .~4

FIG, 2.-New varieties of Japanese cane.

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* ;r6


Report For Fiscal Year Ending

June 30, 1914

Hon. P. K. Yonge,
Chairman, Board of Control,
SIR: I have the honor to submit herewith my report on the
work and condition of the Agricultural Experiment Station for
the fiscal year ending June 30, 1914, and I respectfully request
that you transmit the same, in accordance with the law, to the Gov-
ernor of the State of Florida.
The investigational work of the staff has been carried forward
effectively during the year. The good result of cumulative work is
more apparent than before. Many of the problems have now been
under investigation for some years, and these are giving us founda-
tions for the further growth of Florida agriculture. The rapid de-
velopment of the State makes it important to have a large fund of
definite data to present to the agricultural people. The work un-
dertaken is such as will be of immediate value when completed. In
foreign countries, considerable attention has been given to the art
of agriculture in sub-tropical regions, but the amount of work done
on the science of sub-tropical agriculture is small when compared
with that done on the agriculture of temperate regions. The cli-
mate and soils of Florida are different from those of the sub-tropi-
cal regions in which the science of agriculture is being studied. It
is of importance, therefore, for us to foster the technical work that
is being done at the Experiment Station. That our efforts have
been successful is shown by the fact that other Experiment Stations
similarly located have been seeking to employ our workers. Fortu-
nately our men were reluctant to give up the advantages offered by
us in their departments, even for'increased salaries.

xii Florida Agricultural Experiment Station

In the Experiment Station, particular lines of work are taken
up by certain individuals or groups of individuals. These prob-
lems, when properly co-ordinated and studied in a systematic way,
are known as "projects." During the year some of the projects
(such as those of plant diseases and entomology) have been nar-
rowed in their scope, thus allowing the workers to concentrate more
effort on.the principal piece of work, and making it possible to com-
plete certain sections of it in the course of the year.
PLANT INTRODUCTION PROJECT.-The work of introducing
useful plants from other countries has been continued throughout
the year. The number of different kinds that have been brought to
the Experiment Station in the last six years amounts to over thir-
teen hundred (1,324). Special attention has been given to the in-
troduction of field and forage crops. New grasses, new forage
crops, and new legumes have been tested in large numbers. Some
of these varieties were apparently successful for one or two years;
but, on further testing, showed that, owing to certain weaknesses,
they were useless to the farmers of Florida. These were then dis-
carded, and efforts made to improve those that indicated they would
be of greater value to the State. The first introduction of any par-
ticular kind usually consists of a small amount of seed sufficient to
be tried out throughout the year. Different plantings are made
from month to month to ascertain the time of planting which is
most likely to give the best result. When .promising varieties have
been discovered, they are propagated on a large scale to obtain seed
for distribution, if seed cannot be obtained from commercial
sources. Fifty-one kinds of Canavalias (horse bean) have been
tried. The Canavalias seemed to give promise of usefulness as a
cover crop for a large portion of the State. Unfortunately they
are severely attacked by root-knot and, possibly in consequence,
often set no seeds, which seems to preclude their general adoption
as a cover crop. Stock do not relish the forage from the Canavalias
as much as that from other forage plants which can be success-
fully grown in an extensive way. It would thus seem, from the
tests conducted with Canavalias, that they are not likely to make a
profitable .forage or vegetable crop in Florida. Their growth is
sufficiently promising, however, to warrant further tests.
Seven years ago only one variety of the velvet bean family was
known to Florida. It had been introduced from the tropical re-
gion, perhaps by way of the West Indies. When first grown in

Annual Report, 1914 xiii

Florida it was considered useful only as a shade or arbor plant. It
was believed to have poisonous qualities. The value of the Flor-
ida velvet bean for forage was recognized later, and much useful
work was done in the dissemination of information regarding this
variety. The U. S. Department of Agriculture ascertained that in
the tropical regions, especially those of southeastern Asia, many
varieties of velvet beans (Stizolobiums) were found, and efforts
were made to secure seed of as many different kinds as possible to
be tested on'the plant introduction grounds. Through the co-op-
eration of Prof. C. V. Piper, we have been able to introduce and
test eighty-five different numbers at the Florida Experiment Sta-
tion. Some of these varieties, as the Chinese velvet bean and Yo-
kohama- velvet bean, have qualities that make them distinctly valua-
ble to us. Some, however, were so late in flowering and maturing
their pods that no seeds ever ripened at Gainesville. A few were so
late that they did not even bloom before frost. These have been
eliminated, since they probably have no useful place in our agri-
culture. About twelve of the more promising varieties are still
being tested. The Chinese velvet bean (Fig. I), the first seed of
which was grown at the Station in 1910, has proven itself to be of
distinct value to the southeastern United States. Seed of this vari-
ety has been produced as largely as possible, and at the present time
thousands of bushels have made their way into the hands of seeds-
men in the southeastern United States. The particular value of
the Chinese velvet bean is that it ripens two or more weeks earlier
than the Florida velvet bean. It appears also to make as much for-
age as does the Florida velvet bean, or perhaps more: It has the
disadvantage that its pods are likely to burst open and scatter the
seed after ripening.
Among other promising kinds of forage that have been intro-
duced, may be mentioned Japanese cane. TheJapanese cane grown
heretofore in Florida appears to have arrived by way of Louisiana,
having been obtained from Brazil about fifty years ago. This is
the most important forage crop for Florida, since it will produce a
larger yield per acre than anything else that we have tried. It was
thought possible that other varieties growing in Japan might be
even more useful, and the new introductions from Japan show this
to be the case. The introductions of Japanese cane from other
parts of the tropics have not produced so large a yield as those from
Japan (Fig. 2).
DAIRYING PROJECT.-The principal lines of work in dairying

Florida Agricultural Experiment Station

have been carried forward as in the past few years, special atten-
tion having been paid to the amounts of milk produced from cer-
tain amounts of feed consumed. In this way comparisons could be
made with the feeds that are used in other States. Special atten-
tion has also been given to the amount of milk produced by differ-
ent individual cows in the Experiment Station herd.
HOG-FEEDING PROJECT.-Several experiments have been car-
ried out this year to ascertain the amount of velvet beans that can
be profitably fed to hogs for pork production. As a check on this
line of investigation a portion of the herd was fed on corn only,
other lots being fed different mixtures of corn and velvet beans. The
results indicate that the largest increase in weight will be made
when the ration is composed of three parts of corn to one part of
cracked velvet beans by weight.
PLANT PHYSIOLOGY PROJECT.--A considerable amount of data
has been secured as to the effect of different chemicals upon the
growth of citrus trees under exactly controlled conditions. These
trees were planted in a greenhouse to protect them against the va-
riations due to weather conditions. These experiments also avoid
the difficulties encountered in the field from variations in soil. This
work in a large measure complements and supplements that being
done in the citrus experiment grove at Tavares. The data thus
collected give us important fundamental information, especially as
to the effect of different fertilizers in introducing the conditions
known as "frenching" and "mottled leaf" in the grove.
ENTOMOLOGY PROJECT.-Throughout the year most attention
has been given to studies of the woolly whitefly. This is a newly
introduced pest which came to us from Cuba by way of Tampa. It
is capable of doing a great deal of damage in the citrus groves. It
is therefore necessary to have the most complete and accurate data
as to its life-history and its behavior in the State. It is steadily
spreading into uninfested territory, and inflicting varying degrees
of damage upon the citrus groves. Under proper State supervision,
this pest would have been confined to the territory around Tampa
in which it was originally discovered, or would be completely erad-
icated. This would have been particularly easy to accomplish in the
case of the woolly whitefly.
A considerable amount of attention has also been given to a study
of the life-history of the velvet-bean caterpillar, as well as to the best
method of combating this pest.
PLANT PATHOLOGY PROJECT.-The citrus disease popularly

Florida Agricultural Experiment Station

thology. On February I, 1914, Etta V. Means accepted the posi-
tion as Librarian, and resigned on April 20, 1914. On March 12,
1914, R. Hollingshead, A.B. (Cornell University) began work as
Temporary Assistant in Chemistry, and resigned on May I, 1914.
On April I, 1914, Edgar Nelson, A.B. (Cornell University) began
work as Temporary Assistant in Plant Physiology. On April 15,
1914, T. Van Hyning accepted the position of Librarian. In May,
1914, Owen F. Burger, Assistant in Plant Pathology, severed his
connection with the Experiment Station to continue post-graduate
studies at Harvard University.


No. Title. Date and Author.
215 -Harvesting Corn -----------------------July 5, 1913-A. P. Spencer
216 Spraying for the Velvet Ben Caterpillar ---Sept. 20, I913-J. R. Watson
217 Preserving Fungus Parasites of Whitefly --.- 29; I913-J R. Watson
218 Bulletins and Reports on Hand -------------------JanuarySI-, 11j4
219 Sorghum for Hog Pasture ------------- February 14, 1914-J. M. Scott
220 Cowpeas for Hog Pasture ------------ February 21, I914-J. M. Scott
221 Cucumber and Cantaloupe Blight --------March 7, 1914-0. F. Burger
222 Melanose ------__------------------..April 4, 1914-H. E. Stevens
223 Bulletins and Reports on Hand --------------------May 16, 1914
224 Cottony Cushion Scale ------------------ June 6, 1914-J. R. Watson.

115 Sugar and Acid in Oranges and Grapefruit; 23 pages---
------------ --------- ------July, 1913-S. E. Collison
116 Lettuce Drop; 8 pages ----------------- October, 1913-0. F. Burger
117 Tomato Diseases; 16 pages ------------ November, 1913-P. H. Rolfs
118 Sugar-Cane and Syrup Making; 19 pages-November, 1913-A. P. Spencer
119 Fungus Diseases of Scale Insects and Whitefly; 14 pages
November, 1913-P. H. Rolfs and H. S. Fawcett
120 Irish Potatoes in Florida; II pages------- January, 1914-A. P. Spencer
121 Cucumber Rot; 15 pages -----------------.February, 1914-0. F. Burger
122 Citrus Canker; 8 pages -------------------March, 1914-H. E. Stevens
ANNUAL REPORT for 1913; 131 pages, with index to all
publications of the year.

Annual Report, 1914

called Gummosis has been known for a considerable number of
years to be present in Florida. Various explanations as to the cause
of this phenomenon have been given. Continued and careful study
had not heretofore been applied to this particular disease. A con-
siderable amount of time was devoted to it by the plant pathologist
this year, with a view of securing remedies that would prove uni-
formly successful, and also to ascertain the causative agent for this
Citrus Canker, a disease which has but recently made its ap-
pearance in the State, has been given a large amount of attention.
The causative organism of this disease has been isolated, and in-
fections from pure cultures have been made in healthy citrus tissue.
Since this disease had not been studied before, it required much
careful and exact work. A bulletin on the subject has been pub-
lished, setting forth the principal observations made in the labora-
tory and in the field.
SOILS AND FERTILIZERS PROJECT.-This line of work has been
carried-forward essentially on the same basis as last year. Addi-
tional data have been secured from the leaching tanks and also from
the citrus grove at Tavares. The mass of exact data that is being
accumulated from these leaching tanks and from the results of fer-
tilizer experiments carried on in the grove, gives us the best fofinda-
tion for further work in this line with the citrus grove.
PLANT BREEDING PROJECT.-The work of this project has been
carried forward as outlined in last year's report. The selections
from crosses of the Florida velvet bean that gave evidence of be-
ing most promising for crop production in Florida have been grown
on a large scale with a view of further ascertaining their power
of crop production. As the work progresses, earlier varieties and
varieties that produce larger and better crops in the field than those
already known, will be multiplied for seed production in considera-
ble quantity for general distribution in the State. The study of
these crosses has also made clear additions to our knowledge- of the
inheritance of crop production, earliness and lateness, fertility and
sterility, and several other important characters of agricultural
CHANGES IN STATION STAFF.-From July I, 1913, to July I,
1914, the following changes took place.
On July I, 1913, A. C. Mason, B.S. (Michigan Agricultural
College) accepted a position as Laboratory Assistant in Ento-
mology. 'On August I, 1913, J. Matz, B.S. (Mass. Agricultural
College) accepted a position as Laboratory Assistant in Plant Pa-

Annual Report, 1914 xvii


P. H. Rolfs, Director, Florida Agricultural Experiment Station,
SIR: I respectfully submit the following report of the credits
received and expenditures vouchered out of the funds as specified.


Hatch. Adams. Sales.
By balance on hand, July 1, 1913 --------- ----------------- $ 24.09
By appropriation from U. S. Treasury .-- $15,000.00 $15,000.00------
By receipts, Sales Fund ---------------------------------- 1,565.69

Total ----------------- --- $15,000.00 $15,000.00 $ 1,589.78

To salaries -------------- --------- $ 7,291.65 $11,061.50 $ 50.00
Labor ------------------ -------------- 3,257,83 1,045.18 267.54
Publications ----------------------- 687.60 ----- 110.75
Postage and Stationery --------------- 436.02 21.67 53.74
Freight and Express ------------------- 125.58 169.96 5.17
Heat, Light, Water and Power --------- 155.20 54.37 15.88
Chemicals and Laboratory Supplies ----- 18.00 699.95 20.15
Seeds, Plants and Sundry Supplies ------- 154.33 380.16 3.23
Fertilizer ---------------------------------- 228.83 27.60 --
Feeding Stuffs ---------------------------- 1,409.97 ------ )--------
Library -------------- --------- 196.89 6075 58.52
Tools, Machinery and Appliances -------- 208.42 50.57 8.15
Furniture and Fixtures ------------------- 136.75 39.79 10.00
Scientific Apparatus and Specimens ---------------- 400.70----
Live Stock ------------------------------- 273.25 --------- 200.00
Traveling Expenses ------------------------ 150.87 532.47 37.58
Contingent Expenses ------------------- 20.00 1.90
Buildings and Land ----------------------- 248.81 455.33 52.69
Balance ------------------------------------ ----------------- 694.48

Total -------------- -------------- $15,000.00 $15,000.00 $ 1,589.78

Respectfully submitted,


Florida Agricultural Experiment Station

P. H. Rolfs, Director,
SIR: I submit the following report of the Department of Ani-
mal Industry for the year ending June 30, 1914.
During the year, two pure-bred Jersey heifers were added to
the herd: Lady Lu Heiress No. 304099 by Shy Fox's Heir No.
66906 out of Laughing Lady No. 182002, and Queen's Heiress No.
303214 by Shy Fox's Heir out of Golden Queen of Millbrook
181757. These two heifers were purchased from Mr. James Laugh-
lin, Jr., Zellwood, Florida. During the year a Jersey bull was sold
to Jones and Goodwin, of Winter Haven, Fla. Three grade Jersey
cows were added to the herd during the year.
The entire herd numbers 35 cows and heifers, and 2 bulls. Of
this number, ten are pure-bred Jerseys: eight cows and heifers,
and two bulls.
Tables I and 2 give in detail the results obtained with the dairy
herd during the year.


Z CS 'o- 'M

4 2680.7 5.0 134.0 62.53 311.7 99.74
5 834.9 5.7 47.6 21.96 97.0 31.04
6 668.8 4.0 26.7 12.45 77.5 24.88
7 3121.4 4.9 152.9 64.35 362.9 116.13
9 3329.3 4.7 163.0 76.06 387.1 123.87
10 2041.6 4.7 95.9 44.75 237.3 75.93
11 2594.7 5.0 129.7 60.52 301.7 96.54
14 987.9 4.8 47.4 22.12 114.8 36.74
15 2443.3 i 4.7 114.8 53.57 284.1 90.91
16 1914.9 4.4 84.2 39.29 222.6 71.23
17 1624.6 5.3 86.1 40.18 188.9 60.45
18 3192.0 5.2 165.9 77.42 371.6 118.75
19 1476.4 4.4 64.9 30.28 171.6 54.91
21 2282.9 4.0 91.7 42.79 265.4 84.93
37 825.0 5.3 43.7 20.39 95.9 30.69
40 235.6 3.2 7.5 3.50 27.8 8.90
41 408.6 3.2 13.0 6.06 47.5 15.20

*To reduce butter fat to butter, add one-sixth.


Annual Report, 1914


SBreed Date when
Z Breed dried up
0 W Cd 0

1 6 Grade Jersey ------------Jan. 20, '13 365 ...........
2 15 Jersey _------- ------- Jan. 23,'14 169 July 13,'13
4 6 Grade Jersey ---- --- Sept. 25,'13 286 July 27,'13
SJune 15,'14
5 14 Grade Jersey ---------- Oct. 21, '12 .132 Nov. 10,'13
6 13 Grade Jersey ---------- Sept. 10,'12 108 Oct. 17,'13
7 6 Grade Jersey ------- Nov. 3, '13 300 Aug. 30, '13
9 6 Grade Jersey -------------Nov. 13, '13 240 July 13, '13
10 13 Grade Jersey --------- Oct. 8, '13 268 Sept. 6,'13
Apr. 27, '14
11 14 Grade Jersey --------- Aug. 30, '13 348 Aug. 14,'13
14 6 Half Shorthorn and native- Oct. 29,'13 152 Apr. 1,'14
15 5 Grade Jersey ------------ Oct. 30,'13 244 .
16 5 Grade Jersey ------------ Nov. 24, '13 286 Sept. 26,'13
(Died June 19, '14)
17 3 Jersey -------------------- Oct. 14,'13 257
18 3 Tersey ------------------- June 22,'13 359 June 25, '14
19 3 Jersey ------- --------- Tune 24,'13 188 (Dead)
21 2 Grade Jersey ---------- Nov. 21, '13' 215 June 25,'14
37 2 Jersey ---------------- Tan. 13,'14 162
40 2 Grade Jersey ---- ------- Purchased 39 -- ___
41 2 Grade Jersey -------- Purchased 39


Since the last report, the Berkshire boar, Arcadia's Orphan Boy
128584, has been sold. The Berkshire boar, Master's Royal Rival
182203, by Master's Rival 8th 155242 out of Royal Lady 5ist
129284, bred by Magnolia Farm, Muscogee, Fla., was purchased.
The Berkshire sow, Bonnie Lass K 181708, by Columbus Lee 3rd
92309 out of Predominant's Eminence 123734, bred by T. S. White,
Lexington, Va., was also purchased. Master's Royal.Rival 182203
has proven himself to be a good breeder, as has also Bonnie Lass
K 181708. A number of boar pigs were sold during the year to
farmers in the State.


During the year, two feeding experiments have been conducted,
in which thirty-five head of hogs were used. In both of these ex-
periments corn and ground velvet beans were the grains used.

Florida Agricultural Experiment Station

The first test began January 9, 1914, and closed February Io,
1914, lasting 31 days. In this experiment, fifteen head of pigs
were used. They were divided into three lots of five pigs each, as
nearly equal in size and quality as it was possible to divide them.
Lot I, consisting of five pigs, was fed shelled corn and dwarf Essex
rape. Lot II, consisting of five pigs, was fed shelled corn, ground
velvet beans and dwarf Essex rape. The ground velvet beans were
fed in the proportion of one part ground velvet beans to three parts
of corn by weight. Lot III, consisting of five pigs, was fed shelled
corn and ground velvet beans equal parts by weight. All of the
lots received the same amount of dwarf Essex rape.
Tables 3, 4, and 5 give the results in detail.


Lot I Lot II Lot III

Weights at beginning of test, Jan. 9, 1914--------- 439.0 446.3 430.6
Weights on Feb. 10, 1914, after 31 days ---------- 486.3 481.6 461.6
Total gain per lot in 31 days --------------------- 47.3 35.3 31.0
Average daily gain per head .--------------------- 0.31 0.23 0.20
Average weight at beginning ----------------- 87.8 89.3 86.1
Average daily gain per 1000 pounds live weight..-- 3.47 2.52 2.32
Pounds of feed to make 100 pounds gain ----------- 1835.1 2458.9 2800.0
Cost per pound of gain ------------------------- $ 0.111 $ 0.134 0.126


Lot I Lot II Lot III

Corn --------------------------------------------- 8 6 4
Velvet beans, ground ----------------------- -- 2 4
Dwarf Essex rape ----- ------------------ 20 20 20


Lot I Lot II Lot III

Corn ----------------------------------------- 248 186 124
Velvet beans, ground ----------------------------- -------- 62 124
Dwarf Essex rape ---------------------------- 620 620 620
Totals------------------------------------ 868 868 868

Annual Report, 1914

The second pig-feeding experiment was conducted from June
2, 1914, to July I, 1914. In this test twenty pigs were used. These
twenty pigs were divided into five lots of four pigs each, and were
fed as follows.

Lot I. Corn only.
Lot II. Corn three parts, and cracked velvet beans one part by weight.
Lot III. Corn and cracked velvet beans, equal parts by weight.
Lot IV. Corn and cracked velvet beans, equal parts by weight, plus iron
Lot V. Corn three parts, cracked velvet bean meal one part by weight,
plus iron sulphate.

In this test, Lot I, fed on corn only, made the smallest gain, and
the cost per pound of gain was a great deal more than for any of the
other lots of pigs. The pigs in Lot II made the largest gain of
any. However, the cheapest gains were made by Lot III. Lot II
required less feed to make ioo pounds of gain than did any of the
other lots.
Tables 6 and 7 show in detail the results of the test.


Lot Lot Lot Lot Lot
Weight of pigs at beginning, June 2, 1914-- 252.3 253.3 255.6 254.6 |250.0
Weight of pigs at end, July 1, 1914----------- 307.3 328.3 322.6 317.3 314.0
Gain per lot in 30 days --------------------- 55.0 75.0 67.0 62.7 64.0
Daily gain per head ------------------- 0.46 0.63 0.56 0.52 0.53
Daily gain per 1000 pounds, live weight ------ 7.26 9.70 8.73 8.20 8.53
Cost per pound of gain --------------------- 0.11$0.067 0:0570.0610.079
Pounds of feed to make 100 pounds of gain- 654.5 480.0 37.3 574.2 562.5

Price of Feeds: Corn, $1.75 per Ioo pounds; Bean meal, $040 per Ioo pounds.


*Lots IV and V were given iron sulphate at each feed.

xxii Florida Agricultural Experiment Station

It is evident from the tables that the pigs in the first experi-
ment did not make as good daily gains as did the pigs in the second
test. This accounts in a large measure for the high cost per pound
of gain.
In the second test the daily gain was nearly double that made
by the pigs in the first test.
The best results were obtained from lot I in the first test, fed
shelled corn and dwarf Essex rape.
In the second test the best daily gain was produced by lot II,
fed shelled corn three parts and cracked velvet beans one part by
weight. The cheapest pork was produced by lot III in the second
test. In this test it cost 5.7 cents to produce one pound of gain. In
the first test the cost per pound of gain was II.I cents. When we
compare the cost per pound of gain of the various lots in the second
test, it is very evident that corn alone is an expensive feed when
compared with corn and velvet beans.

SOUDAN GRASS (S.. P. I. No. 25017.)
Six plots were seeded to Soudan grass. These plots were run
in duplicates, hence the results obtained ought to be a fair indica-
tion as to what Soudan grass will do in Florida. The object of
the experiment was to obtain information as to the probable yield
of hay at different dates of seeding, also as to the best time for
sowing Soudan grass seed. The seed on all plots was sown broad-
cast at the rate of 24 pounds per acre. All plots were treated alike,
but had different dates of planting. Tables 8 and 9 give the results
in detail.

Mar. 133800 12 80 j
a) Q 75-

0. 1 6000 3 0 S 2 400 1220 84 00 C50
o) > d'-. : !. .. :1 z. ::I d PO a: a

I Mar. 7Jun. 13 3800 1280
II Mar. 17 Jun. 13 4000 1400 ---------------1--------
IIIiApr. 1 Jun. 28 6400 2300 Sept. 23 2500 1200 8900 3500
IV;Apr. 17 Tul. 18 6000 3230 Sept. 23 2400 1220 8400 4450
V May 1 Jul. 28 6100 2580 Sept. 23 1840 1000 7940 3580
VI May 15 Jul. 29 7600 3660 Sept. 23 2400 1300 10000 4960

Annual Report, 1914

Duplicates of the above plots were planted, the results of which
are given in table 9.
It will be seen from tables 8 and 9 that the largest yield of hay
per acre for the season was obtained from plot VI. The sowings
made in Mlarch produced only one cutting during the year, while
the later sowings gave two cuttings.

TEFF (Eragrostis abyssinica)
Teff is an annual grass introduced from Africa, which is sup-
posed to be its native home. In Africa there are two varieties cul-
tivated, a white and a red. The white variety is considered the best.
In Africa the grain is used for the manufacture of flour from which
bread is made. The bread is said to possess a slight but agreeable
acid taste.
Several plots of Teff were tried, but all proved a failure. The
plots were planted at different dates. The first planting was made
on April 17 and the last planting on June 16. In all, eight plots
were planted. On four of these the seed was sown broadcast, and
on four it was planted in rows. None of the plots produced a suf-
ficent growth to justify harvesting the crop.

A test of the comparative yield of green material from four
varieties of Japanese cane was made during the year. These four
varieties were all planted at the same time (November 12). They
were also planted as nearly alike as it was possible, that is, the same
number of seed canes was used, and the canes were cut to the same
length. They were all fertilized the same, and the cultivation was
the same for all four varieties.
Table o1 gives the yield per acre of each variety.


The fertilizing experiment on Japanese cane has been under ob-
servation for five years, having been started in the spring of 1909.
The only remarkable yield obtained was the yield from plot VIII
in 1909. Plots VII and VIII were fertilized and treated the same
in all respects, except that plot VIII was given an application of
ground limestone at the rate of 2000 pounds per acre. For the
year 1909, plot VIII gave a yield of 10.4 tons more green material


Florida Agricultural Experiment Station.



--4 t" ,- "

r. Co) o 0 ,C Id 0
Z R. 0 ( > ", EM a) ,
Q c C i ci I, n C a) '4.2ocai
*Sb, *- O^ R, e
o. ^g gg ^ g'^ 3g-gg

I Mar. 7Jun. 13 3660
II Mar. 17iJun. 14' 3900
III Apr. 1 Jun. 28 4900
IV Apr. 17Jul. 19: 5800
V May 1 Jul. 28 5700
VI May 15Jul. 29 6700
15 6700

-- ----- -------
- --- ------
-- -- -- ------
Sept. 23 600
Sept. 23 700
Sept. 23 1160

per acre than did plot VII. Lime was also applied to plot VIII
at the rate of 2000 pounds per acre in 1911 and 1913, but the
ground limestone applied in 1911 and 1913 seemed to have had no
influence in increasing the yield. The average yield for five years
for plot VII is 12.94 tons, and for plot VIII 15.26 of green
material per acre, with a difference in favor of ground limestone
of 2.32 tons of green material per acre.
In studying over table II which gives the results of five years
work, it might be well to call attention to the following: (i)
Potash gave a decided increase in yield. (2) Ammonia gave an
increased yield. (3) Sulphate of ammonia produced a little bet-
ter yield on the average than did dried blood. (4) Acid phosphate
apparently gave no increase in yield. (5) Sulphate of potash pro-
duced a little better yield than did muriate of potash.


S. P. I. No. Yield of green material in tons per acre
30464 ------------40.38
29106 -----------38.25
29109 ---------------------34.47
28193 -------------34.32

In the spring of 1914 a more extended fertilizer experiment
with Japanese cane was begun. It consists of twenty-three plots.
Each plot contains 4770 square feet. The various plots are to be
fertilized as shown in Table 12.






Annual Report, 1914



Plot Plot Plot Plot Plot Plot Plot Plot

Dried blood, pounds -- 112 -- 112 -- 112 --- 112 112
Sulphate ammonia ---- ------- ----- 72 ------ 72----
Muriate potash .------. 84 84 ------ 84 84 --
Sulphate potash -------------- ------ ---------------- 84 84 84
Acid phosphate --- ------ 224 224 224 224 224 224 224
Ground limestone* ----------- --- ----------------------- 2000

Total per acre .--- 196 308 336 380 420 380 420 420

Yield, tons, 1909-------- 24.2 17.7 16.1 19.1 19.5 18.9 16.6 27.0*
Yield, tons, 1910--- ---- 14.6 12.4 10.0 14.4 11.8 16.7 14.1 16.0
Yield, tons, 1911 ------- 7.08 9.0 9.63 14.36 13.56 15.48 14.02 14.10*
Yield, tons, 1912----- 6.38 6.84 3.68 7.92 7.26 9.62 10.68 10.28
Yield, tons, 1913------ 8.16 6.93 3.83 8.51 8.09 7.86 9.33 8.92*

Average per acre ... 12.08 10.57 8.64 12.85 12.04 13.71 12.94 15.26

*Ground limestone was applied in 1909, 1911 and 1913.


o o i

ro 13
0 41 0c 0 t

1 -84 150 -- -- 60 2000
2 123.5 -- 150 ----- 60 2000
3 Barnyard manure 30 loads per acre
4 -------- 123.5 ----------------_ 75 --------. 60
5 -------- -----------.. 84 150 -------_-------- 60
6 --_.._.__.---...... 84 --------.... 75 ---.. 60
7 ---------- -----. 84 ----____---_-----. --- --- 60 2000
8 -------------------- 84 --------------- 133 60
9 Check
10 ----------------- 84 _____-------- -------__-------- 2000
11 ------------------- 84 -------- 75 .
12 ------ 123.5 -------- --..-- 75 _
13 116.6 ------------------- -..----- ------- -- 60
14 .----- 123.5 ----------------__------___-_ ----. 60
15 -------- 84 ---------.--- 60
16 -------------------------------------------_ 133 60
17 --_-----------_---- --- ----- ----- - -
18 ------ -- ----- .--- -----_ 75 ----- -- : ----
19 ---- ----------- 150 ..
20 Check
21 -- 123.5
22 116.6 ---- -. ..- .....
23 ------ --------------- 84 ------- ------- _


Florida Agricultural Experiment Station


On May 20, 1913, four families of Wakulla, two of Florida
Velvet, and two of Alachua, were grown in adjacent plots of I,ooo
square feet, together with two plots of Yokohama. There were 3
rows in each plot, 3 feet apart, and the seeds were sown from I1
to 2 feet apart. Six feet separated the rows of adjacent plots.
In such tests, on a small area, the stand is of the first impor-
tance, and this depended here mainly on the quality of the seed,
which was not selected in any way. Three plots of Wakulla, and
the two plots of Florida Velvet showed a good stand. One plot of
Wakulla had a poorish stand. The two plots of Alachua,. and one
plot of Yokohama had a poor stand. The other plot of Yokohama
had a very poor stand. Hence, so far as stand goes, the compari-
son of yield can only be made between the Wakulla and the Florida
On August 18, the Wakulla had nearly finished flowering, and
growth of vines had ended. Alachua was beginning to flower. The
Florida Velvet had no flowers.
The pods were picked in and after September. Weighed when
quite dry, they gave the amounts shown in Table 13.

216-1-17 ---------------------------------------- 94%
216-1-28 ----------------- ------------ --- 124%
216-1-35 --------------------------------------------------119%
216-1-27 ---------------------- --------- ----- 1094
1 -- -- ----------------------------- 19
2 _------------------------ 56
515-27-35 -------------------------- ----------29%
515-27-14a ---------------- ------------------51
1 --------- 27%
2 ----------------------------------- 23

An early drought, an attack of caterpillars (for which they
were sprayed) and a comparatively early frost, diminished the yield
of all late plants in 1913.
The average yield of Wakulla was: 112 pounds of dry pods to
Iooo square feet, or 4879 pounds per acre.

Annual Report, 1914

Now 4734 lbs. of dry pods were carefully shelled by hand, and
gave 324 lbs. of clean seed. This is 68 per cent of seed, and one
bushel of this seed weighed 67 lbs. Hence the average yield of
Wakulla was at the rate of 4912 bushels of clean seed per acre.
But there was a space of 6 feet between the plots, while only 3 feet
was between the rows. Hence the outer rows of the three in each
plot had more space. If we count in all this space, the area of each
plot is increased by one-third, and the yield is 49y2 bushels to I 1-3
acre, or 37 bushels per acre. Hence, the true yield was between
37 and 49y2 bushels per acre of clean seed, 67 pounds to a bushel.



Yield of
Plot Variety green forage
Tons per acre

1 Brabham Cowpeas --- 14 ---- 3.85
2 Soy bean S. P. I. No. 1495 inoculated 1.28
3 Soy bean S. P. I. No. 25118 Not inoculated 1.75
4 Soy bean S. P. I. No. 25135 Not inoculated 1.98
5 Soy bean S. P. I. No. 14953 Inoculated_--. 0.82
6 Soy bean S. P. I. No. 251181Inoculated..__ 2.22
7 Soy bean S. P. I. No. 25135 Inoculated.--- 1.75

Yield of
dry hay*
Tons per acre

Yield of Seed Per Acre.

Plot Variety Pounds Bushels
per acre per acre

1 Brabham
2 Soy bean
3 Soy bean
4 Soy bean
5 Soy bean
6 Soy bean
7 Soy bean

Cowpeas --- ---- ------
S. P. I. No. 14953 Not inoculated
S. P. I. No. 25118 Not inoculated
S. P. I. No. 25135 Not inoculated
S. P. I. No. 14953 Inoculated_ .--
S. P. I. No. 25118 Inoculated--
S. P. I. No. 25135 Inoculated_-..



*Estimated that the green forage lost 70 per cent in drying.

A comparison was made of the yield of green hay and seed from
three varieties of soy beans and Brabham compeas. For the soy
beans, three plots were inoculated with soil from a soy-bean field,
while three plots were not inoculated. The Brabham cowpeas were
not inoculated. The soy beans and cowpeas were planted on July


Florida Agricultural Experiment Station

12, 1913. They received the same cultivation during the summer.
No fertilizer was applied to the plots.. They were harvested Octo-
ber 3, 1913, eighty-three days after planting. The plots from which
seed was saved were not harvested until later.
From the results obtained, it is quite evident that Brabham cow-
peas will produce a much heavier yield per acre of forage than will
soy beans. The results of this year's work do not indicate that soil
inoculation is of much importance. There is little difference in
the average yield of the three inoculated plots and the three plots
not inoculated. There is, however, considerable difference between
the plot giving the heaviest yield and the one giving the smallest
yield. Table 14 gives the results in detail.


In April, 1912, a small quantity of sweet potato seeds was ob-
tained from Barbados. These seeds came from varieties that pro-
duced the largest yield per acre in Barbados.
In 1912 we only had a few plants of each, so no attempt was
made to make a yield test. In 1913 we still did not have enough
plants of each to make a yield test, but there was a sufficient num-
ber of plants of each to make some comparison. Out of some fif-
teen or sixteen seedlings there are some three or four that give
promise of being of some value.


The spring of 1913 a large area was planted to Chinese velvet
beans. This gave a good opportunity to study the yield per acre
that they would produce. On three acres the yield varied from 20.9
bushels to 27.1 bushels per acre, with an average of 23.2 bushels
of cleaned seed.
These beans were all planted in rows four feet apart and from
one and a half to two feet apart in the row.
For comparison, another acre was planted with sorghum and
Chinese beans in alternate rows. This made the rows of beans 8
feet apart. Planted in this way they gave a yield of 26.9 bushels
of cleaned seed per acre. This shows a difference in favor of plant-
ing in alternate rows with sorghum or some other crop.
It was intended to make a comparison in yield of Florida, Chi-
nese and Lyon velvet beans, but the caterpillar injured the Florida


Annual Report, 1914 xxix

and Lyon beans to such an extent that it was not possible to make
a comparison.

The kudzu was cut only once during the year, on August 14,
1913. At this time it produced a yield of 2520 pounds per acre of
cured hay.
Animal Industrialist.

Florida Agricultural Experiment Station

P. H. Rolfs, Director,
SIR: I herewith submit the report of the Plant Physiologist
for the fiscal year ending June 30, 1914-
The work of this year has been a continuation of that of the
previous year. In addition to the work on Dieback, series of ex-
periments have been carried out to determine the effects of fertili-
zer combinations, sources, and quantities upon the growth of citrus.
This report contains a description of some of these series. The
work done on this problem can only be considered as preliminary.

This experiment was started for the purpose of inducing the
physiological disturbance in citrus trees known as Dieback, by caus-
ing a condition similar to that known in the grove as lack of drain-
age. Although this disturbance did not develop, certain types of
vegetative growth were produced which appear to be characteristic
for the treatment given. These types are so distinct that they are
worthy of report.
The types of growth produced were not at all the same that
characterize trees which are developing the physiological disturb-
ance Dieback, namely, a luxuriant vegetative growth of a deep
green color. Hence, it is to be concluded, that the experiment did
not exactly reproduce the field condition known as lack of drainage
which can bring on the Dieback.
EXPERIMENT.-This experiment was started in October, 1912.
The material consisted of 30 pineapple orange trees budded on
sweet stock. The trees were one-year buds on two-year stocks,
and were of uniform size, appearance, and thrift. They were
planted in 30 galvanized iron tanks which were painted inside and
outside with a waterproof paint. The tanks were 35 inches in depth
and 12 inches in diameter, and were closed at the bottom. They
were filled with soil to within 6 inches of the top. The soil used
was from the first nine inches of a sandy loam field soil of good
tilth, which has been under cultivation several years. It had grown,
during the past two years, a luxuriant growth of velvet beans that
was plowed under in the spring. After collection, the soil was well
mixed so as to insure uniformity.
The tanks were arranged in the greenhouse in three rows run-
ning the length of the house. Each tank was partially embedded in
the ground floor of the house. The experiment was divided into


Annual Report, 1914

three series of ten plants each. In the tanks of Series I, sufficient
water was kept so that the water table stood about 7 inches from the
soil surface; and in Series II, 14 inches. In Series III, the attempt
was made to keep the soil moist to the bottom of the tank without
allowing any saturation. This attempt was not successful, as from
time to time it was found that the lower soil layers had become
almost air dry. Each time that this was found, water was added so
as to overcome this condition. Thus the moisture conditions for
Series III may be described as alternately moist and dry, with no
During the experiment no mineral fertilizer was given the trees,
so that the food supply in the soil was uniform for the experiment,
with the exception that from 'October 23, 1913, four trees of Series
I, and three trees of each of Series II and III were each given about
500 cc. of a manure extract once a week. No differences have de-
veloped between the fed and the unfed trees, hence the feeding has
not been taken into consideration.
RESULTs.-When planted, the trees were pruned back to a single
stem. The first flush of growth put out within three weeks after the
trees were planted. About ten days elapsed between the appear-
ance of the first stems and the last. At maturity, no differences were
evident to the eye. There was an apparent uniformity of size and
color throughout the different series. No measurements were made.
The second flush of growth appeared in February, 1913. The
third flush was made from June to September, 1913. No marked
differences were evident to the eye between the different series at
the maturity of the second flush. The foliage of the trees in Series
I showed a yellowish tint. The foliage of Series II showed a nor-
mal green, whereas that of Series III was a shade lighter in color.
There was a suggestion of a ranker growth in Series II. In Series
I, the stems were somewhat shorter than in the other series.
In October, 1913, the differences between the different series
were marked. The stems and the foliage of Series I were sparse
and very yellow. There had been some dropping of leaves, par-
ticularly in trees Nos. I, 4, 6, 9 and o1. The stems were neither
long nor slender, nor were they markedly angular. The bark of
the trunks had a hide-bound appearance. The general look of the
trees was open and sickly.
The trees of Series II had made a good growth. The general
color was a normal green. The leaves appeared normal to above
in size. The stems were long, and somewhat angular. The bark


Florida Agricultural Experiment Station

of the trunk and stems had a healthy green look. The general
growth was luxuriant.
The trees of Series III had also made a good growth, but the
stems were shorter, more plentiful, more slender and less angular
than those of the trees in Series III. The leaves appeared normal
to below normal in size. Their color was a lighter green than
that of Series III. The bark of the trunk had a healthy green
Measurements made of the leaves on the trees of the different
series showed the average size of leaf for each series to be as fol-

Series Leaf Length Leaf Breadth
I 84 mm.* 49 mm.
II 101 mm. 61 mm.
III 90 mm. 52 mm.

*1 mm. is nearly one-twenty-fifth of an inch.

In February, 1914, the fourth flush of growth was made. At
this time there were marked differences between the different se-
ries. In Series I, the amount of new growth that had been made
was rather small and scattered. The new stems were comparatively
short and thick. The leaves were undersized, sparse and yellow.
The trees in general had a starved, diseased appearance.
In Series II, the number of new stems was not large, but they
were lengthy, angular, somewhat upright and with rather large-
sized leaves. The color was normal green. The general character
of the growth was rank like watersprouts, but not so succulent.
In Series III, when the growth was first put out, the stems were
very slender and short. The leaves were small, linear and mouse-
ear-like in shape and position. *The color was light green. The
growth appeared starved. At this time, examination showed the
lower layers of the soil in the tanks of this series to have become
quite dry. The soil was then moistened. At this time the growth
was slow and had not reached maturity. With the better moisture
conditions in the soil, growth was quickened and the stems and
leaves increased in size. At maturity, the stems were still short,
slender, and somewhat angular. The leaves were undersized and
had the mouse-ear-like appearance in shape and position. They
showed a crinkling in the centers along the mid-ribs. The number


Annual Report, 1914

of stems formed at this flush of growth was large, and being short,
they gave a rounded bushy appearance to the heads of the trees.
In June, 1913, the experiment was closed, and final measure-
ments were made. The averages of these measurements are given
in the following table. The measurements were confined for the
most part to the fourth flush of growth, which at this time formed
the terminal growth. The diameters of the trunks just above the
unions of scion and bud were determined


4d a) z.

I 25 64 mm.* 2.8 mm. 59 mm. 27 mm. 20.7 mm
II 29 126 mm. 2.83 mm. 82 mm. 40 mm. 2425 mm
III 75 75 mm. 2.13 mm. 61 mm. 29 mm. 24.4 mm.

*1 mm. is nearly one-twenty-fifth of an inch.

In closing the experiment, the roots were removed intact from
the soil, by washing. The roots of the trees in Series I had grown
down to the water-table and there stopped. A few of the trees
showed a small amount of sloughing of the roots where they had
dipped into the water. Fig. 3, No. I, shows a typical tree of this
The roots of the trees of Series II completely filled the soil down
to the water table. A small amount of sloughing of the roots oc-
curred where they dipped into the water. Fig. 3, No. 2, shows a
typical root system of this series.
In the tanks of Series III, the mat of roots extended entirely
to the bottom. Fig 3, No. 3, shows a root system from this series.
Large main roots extended downward from the crown, which was
not the case in the other series. No other differences in the branch-
ing of the roots was noted. They were of good color and had a
plentiful supply of fibrous roots.
A comparison of the extent of the root systems and the amount
of top developed in the different series suggests a correlation of
root and branch development within certain limits. Series I sug-
gests the type of growth that is likely to be obtained when young




Fr T- 1 Hart, from ceris T IT swl III of t .

~`~"""^' ~~" """' "'"`' '' """ -~~ `~~ ~"- ~~~~ ~~~~-~ '

Annual Report, 1914 xxxv

trees are planted on lands in which the water-table reaches too near
the surface of the soil during any considerable period of time.
Series II is the type of growth that will obtain where there is room
for root development in the soil, along with a constant supply of
moisture during the growth periods. This type of growth is met
with more commonly in the hammocks where the supply of moist-
ure in the soil is more constant. Series III is the type of growth in-
dicative of irregular moisture conditions in the soil, particularly
at the periods of year when the flushes of growth are being made.
This type of growth is frequently met with in trees planted on the
high pine lands, where moisture conditions are irregular. How-
ever, on these same lands, if the distribution of the rainfall is good
during several successive seasons, a type of growth varying towards
that of Series II will probably occur.
Since the food contained in the soil was constant for the dif-
ferent series, with the exceptions noted, the uniformity of growth
in the individual series suggests that the supply of moisture availa-
ble for the tree is a controlling factor in the determination of the
growth type; and conversely, the type of growth in the tree is indi-
cative of the moisture conditions prevailing in the grove, within
certain limits.


This experiment is a continuation of that reported upon for
1913 (Fla. Agr. Exp. Sta. Report 1913, p. xliv). It differs in
that the soil used was a field soil with a good humus content, and in
the duration of the experiment having been longer. The purpose
of the experiment was to determine the differences in growth in-
duced by the fertilizer applications when the citrus seedlings were
grown in a field soil. The results are compared with those obtained
in the 1913 experiment in which the seedlings were grown in pure
sand. A system of measurements similar to those made of the seed-
lings in the 1913 experiment has been carried out. This experiment
is a preliminary one of a series of experiments to be conducted to
determine the effect of quantities, sources, and combinations of
fertilizers upon the growth of the citrus tree. Since the experiment
is only preliminary, the results should not be looked upon as con-
EXPERIMENT.-This experiment was conducted upon the east
bench of the greenhouse in the same location as the 1913 experi-
ment. It consisted of 18 series of five pots each. The pots were six

Florida Agricultural Experiment Station

inches in diameter, and their walls had been soaked in melted paraf-
fin. The pots were embedded in a soil which was obtained from a
depth of about four feet in the field outside the house. The soil
used in the pots for a growth medium was from the first six inches
in the same field. The soil was a sandy loam of good tilth. Its
humus content was about 1.7 per cent. The field was one that had
been under cultivation for several years, but no fertilizer was ap-
plied. Velvet beans had been grown in the field and turned under
in the spring. The soil produced a good growth of the beans.
The experiment was started in July, 1913. The fertilizer was
applied on July I. The amounts and kinds applied are shown in
Table 17. The complete fertilizer for each pot was well mixed be-
fore application. It was then stirred into the dry soil, and the soil
wetted. The lime was not applied at this time, but was added on
July 21.
On July 25, the seeds were planted. They were grape-fruit
seeds of uniform size that had been freshly removed from the fruit.
They were planted to a depth of iY2 inches. The soil was then par-
tially covered by a circular paraffined filter-paper, and mulched with
sphagnum moss, to avoid a too rapid drying out. The paper and
mulch were allowed to remain until the plants began to break
through the soil surface. The first plants appeared on August I.
Most of them were through by August 19, and nearly all by August
23. The experiment was allowed to run until June, 1914. In the
meantime no other fertilizers were applied. The moisture condi-
tions of the soil were kept uniform. As there was no heating sys-
tem in the greenhouse, the plants were exposed to nearly the same
variations in temperature as prevailed outside the greenhouse.
Results.-Measurements were made of the stem lengths and the
length and breadth of the leaves in December, 1913. In June, at
the time the experiment closed, these measurements were repeated,
additional measurements were made of the stem diameters, and the
green weights determined. Tables 18 and 19 show the measure-
ments as determined at these times. They also show the position of
each series in reference to the one making the best growth as shown
by the measurements of the particular plant parts. This position
is spoken of as the relative position. The last column (D) of each
table shows the average of all of the relative positions which each
series occupies.
Tables 20 and 21 are arranged for the comparison of the results
of this experiment with such data from the sand cultures with cit-
rus seedlings (1913, 1. c.) as are comparable. Since the two expe-


Annual Report, 1914

riments differ in their duration, only the measurements of the
second experiment taken in December, 1913, are comparable. In
determining the average relative positions, such combinations as
were not common to the two experiments were omitted.
Table 20 shows the different sources and combinations of fer-
tilizers that were used, and the average relative positions occupied
by each series in reference to the source or combination giving the
greatest amount of growth, based on the measurements of this ex-
periment in December, 1913. (See Table 18). The last column
and the lowest line of figures in Table 20 show the general average
of the average positions occupied by the different combinations
containing a particular fertilizer. In determining the relative posi-
tions, the combination of nitrate of soda and basic slag has been
omitted, so that the data may be comparable with those shown in
Table 21.
Table 21 shows the same as Table 20, but is based on the
measurements of June Io, 1913, of the plants of the sand cultures
with citrus seedlings (Rept. for 1913). In order to make this table
comparable with Table 20, the average positions are calculated from
the stem lengths, leaf lengths and leaf breadths only, with the omis-
sion of the combination of dried blood, acid phosphate and lime,
which is not common to the two experiments.
A survey of the tables shows a very complete readjustment of
the positions which the different series occupy in this experiment,
as compared with those of the 1913 experiment. In the experiment
sulphate of ammonia shows the highest average among the ammo-
niates, while results from different sources of phosphoric acid aver-
age the same. In the 1913 experiment, dried blood shows the high-
est average of the ammoniates, and basic slag of the sources of
phosphoric acid.
Fig. 4 shows the variations in stem length of the plants, (I)
when grown in soil (see Table 18); and (2) when grown in pure
sand (see table XV, Fla. Agr. Exp. Sta. Report for 1913, p. lii).
The measurements of the series not common to the two experiments
have been omitted. The serial numbers are the same as shown in
Table 20. The curve representing the stem lengths of the plants
grown in the field soil approaches much nearer a straight line than
does that representing the plants grown in pure sand, indicating
much less variation from the use of the different fertilizers when
used on a good soil than when used on a soil poor in humus and or-
ganic matter.
In November, 1913, the plants, irrespective of series, showed a


xxxviii Florida Agricultural Experiment Station

yellowish color of the foliage, which was not at all characteristic
of the foliage of orange trees in their winter condition. The gen-
eral color suggested nitrogen hunger. This color was most promi-
nent during the winter months. In the spring, the plants partially
recovered the green color. The recovery was probably due to the
nitrogen supply being renewed through bacterial activity in the soil.


During 1913, a pot experiment with the growth of grape-fruit
seedlings in pure sand was carried out in connection with different
fertilizer combinations. (Fla. Agr. Exp. Sta. Report for 1913,
p. xliv). As quite marked variations in growth were obtained, it
was thought best to make this experiment again. It was conducted
on the west bench of the greenhouse, on the opposite side of the
house from where the 1913 experiment was conducted. It con-
sisted of 19 series, and included the combination of nitrate of soda
and basic slag which was omitted from the 1913 experiment.

3 \ I ; ;

FIG. 4.-Diagram showing stem-lengths of plants in field soil (A), and plants
in pure sand (B). The plants in soil were measured in December, 1913 (see
table 18). The plants in sand were measured in June, 1913 (see table XV,
of the Report for 1913). The numbers of the series are those given in
tables 20 and 21.

The pots were filled with sand and the fertilizer applied on Feb.
21, 1914. The lime was applied on March 2. Table 17 shows the
amounts and sources of the different fertilizers used at this time.
The grape-fruit seeds were planted on March 7, and the soil was
covered with a circular paraffined filter-paper and mulched with
sphagnum moss. The paper and moss were removed when the
first plants began to break through the soil surface. Nearly all of
the plants were above ground by April 18.

Annual Report, 1914

RESULTS.-On June 5 the different series showed considerable
variation in reference to color. The dried blood plus dissolved
bone-black and the dried blood plus basic slag series showed the
deepest green color. The dried blood, acid phosphate and lime
series showed the next deepest green. The series fertilized with
lime alone showed the most yellow in the foliage. The sulphate of
ammonia, acid phosphate and lime series showed the greatest
amount of and most distinct frenching. The following series showed
more or less frenching.

Sulphate of ammonia and acid phosphate.
Sulphate of ammonia and dissolved bone-black
Nitrate of soda and acid phosphate.
Nitrate of soda and dissolved bone-black.
Nitrate of potash and acid phosphate.
Nitrate of potash and dissolved bone-black.
Dried blood, acid phosphate, and -lime.
No fertilizer.
Nitrate of soda, alone.

The experiment was closed on June 21, 1914. At this time the
same measurements were made as in the 1913 experiment, with the
exception that the dry weights were not determined. Table 22
shows the measurements made at this time. It also shows the rela-
tive position of each series in reference to the best growth made
by the particular plant part, and the average of the relative positions
occupied by each series.
Table 23 shows the different combinations of fertilizer sources
used and the average position of each arranged for easy inspection.
The last column and the lowest line show the general averages of
the different average positions occupied by the fertilizer combina-
tions with a particular source.
Table 24 is similar to Table 23, and shows the data from the
1913 experiment which was taken as a standard. A comparison of
the tables shows that the individual series were not entirely dupli-
cated, but a comparison of the general averages shows a nearly
complete duplication of the groups of series containing a common
source of ammonia or phosphoric acid. Of the sources of am-
monia, dried blood gave the highest average, whereas sulphate of
ammonia gave the lowest in one table, and nitrate of soda in the
other. Of the sources of phosphoric acid, basic slag gave the
highest average, while acid phosphate gave the lowest. However,
when lime was used in connection with the acid phosphate, fully
as good growth was obtained as from basic slag.


Florida Agricultural Experiment Station


Series Fertilizers Amend- nd Ceso.
Nos. ments 1913u

I Sulph. Ammonia- Acid Phosph._. H. G. Sulph. Potash ------- 1
5 grams 7.5 grams 2.5 grams
II Sulph. Ammonia- D. Bone B.-- H.G. Sulph. Potash -------. II
5 grams 7.0 grams ; 2.5 grams
III Sulph. Ammonia- Basic Slag--.. H.G. Sulph. Potash ---- III
5 grams 6.6 grams 2.5 grams
IV Nitrate Soda.-- Acid Phosph.-- H.G. Sulph. Potash ------ IV
6 grams 7.5 grams 2.5 grams
V Nitrate Soda---- D. Bone B..... H.G. Sulph. Potash _------_ V
6 grams 7.0 grams 2.5 grams
VI Nitrate Soda-- Basic Slag--. H. G. Sulph. Potash----- t
6 grams 6.6 grams 2.5 grams
VII Dried Blood --. Acid Phosph.-- H.G. Sulph. Potash ------ VI
5.5 grams 7.5 grams 2.5 grams
VIII Dried Blood --- D. Bone B ..-- H.G. Sulph. Potash----- VII
5.5 grams 7.0 grams 2.5 grams
IX Dried Blood--- Basic Slag-.- H.G. Sulph. Potash----- VII1
5.5 grams 6.6 grams 2.5 grams
X Nitrate Potash-- Acid Phosph..- None --------- IX
7.5 grams 7.5 grams
XI Nitrate Potash.- D. Bone B.---. None ---------- X
7.5 grams 7.0 grams
XII Nitrate Potash-- Basic Slag--. None- ........ XI
7.5 grams 6.6 grams
XIII Sulph. Ammonia- Acid Phosph... H. G. Sulph. Potash Lime-_ XII
5 grams 7.5 grams 2.5 grams 9 grams
t Dried Blood -- Acid Phosph.- H. G. Sulph. Potash Lime_ XIII
5.5 grams 7.5 grams 2.5 grams 9 grams
XIV None ------__ None ---- None -------.. Lime XIV
9 grams
XV Sulph. Ammonia- None ---- None ------- ----- XV
5 grams
XVI Nitrate Soda.. None ---- None ...---- .... XVI
6 grams
XVII None ---____ None H.G. Sulph. Potash ..... XVII
2.5 grams
XVIII No fertilizer---- (Check Series) XVIII
*See Fla. Agr. Exp. Sta. Report for 1913, p. xlvi.
MNot included in sand cultures with citrus seedlings, 1913.
tNot included in pot experiments with citrus seedlings, 1914.

Sulph. Ammonia ----------------------------Sulphate of Ammonia
Acid Phosph. ....--------------.---------------Acid Phosphate
H. G. Sulph. Potash ___.-------High-Grade Sulphate of Potash
D. Bone B. __.------ ------------------ Dissolved Bone-Black

Annual Report, 1914

Measurements made December, I913.

Series Stem Length Leaf Length Leaf Breadth D

I 51.2 78 16 34.5 100 8 16.5 94 10 11
II 51.7 79 15 32.9 96 12 16.9 96 7 12
III 58.5 89 6 38.2 111 1 18.5 105 2 2
IV 61.4 94 4 35.6 103 7 15.6 89 13 7
V 56.1 86 8 31.4 91. 14 15.0 85 15 13
VI 64.1 94 5 31.3 91 15 13.0 74 17 14
VII 49.7 76 17 33.8 98 11 16.4 93 11 15
VIII 56.0 85 9 36.5 106 4 18.6 106 1 3
IX 53.7 82 12 34.2 99 10 16.7 95 8 9
X 63.9 98 3 35.7 104 6 17.2 98 6 4
XI 55.8 85 10 37.0 108 3 16.2 92 12 8
XII 55.3 84 11 24.6 72 18 10.7 61 18 17
XIII 68.5 105 1 37.1 108 2 18.4 105 3 1
XIV 53.0 81 13 31.9 93 13 15.6 89 14 16
XV 56.6 86 7 31.2 91 16 16.6 94 9 10
XVI 47.4 72 18 25.2 73 17 13.7 78 16 18
XVII 52.5 80 14 35.9 104 5 18.4 105 4 6
XVIII 65.5 100 2 34.4 100 9 17.6 100 5 5

A-Average measurements in millimeters. (1 mm. is nearly one-
twenty-fifth of an inch.)
B.-Relative measurements (check series, 100).
C.-Relative positions.
D.-Average positions.

Florida Agricultural Experiment Station

Measurements made June, 1914.

Series Stem
No. Length


I 80 67
II 81 68
III 138 116
IV 187 157
V 114 96
VI 100 84
VII 126 106
VIII 153 129
IX 1154 ,130
X 172 !145
XI 159 134
XII 127 107
XIII 180 151
XIV 120 101
XV 106 89
XVI 90 76
XVII 105 88
XVIII 119 100

Stem Leaf Leaf
SDiameter Length Breadth


18 3.0 77 15 37.2 89 17 18.7 88 18
17 2.2 56 18 39.4 95 15 20.5 96 14
7 3.7 95 8 42.8 103 11 22.1 104 9
1 3.9 100 5 47.6 114 4 24.2 114 3
12 3.6 92 10 43.7 105 8 22.0 103 10
15 3.0 77 16 43.5 105 10 22.6 106 7
9 3.5 90 11 46.3 11 5 21.6 101 11
6 4.0 103 4 43.8 105 9 23.6 111 4
5 3.7 95 9 39.9 96 14 20.4 95 15
3 4.4 113 1 49.5 119 2 25.5 120 1
4 4.3 110 2 50.6 122 1 25.1 118 2
8 3.4 87 13 41.5 100 13 20.9 98 13
2 4.2 108 3 48.3 116 3 23.3 109 5
10 3.9 100 7 46.2 111 6 23.0 108 6
13 3.5 90 12 J44.3 106 7 22.4 105 8
16 3.0 77 17 36.5 88 18 19.5 92 17
14 3.3 85 14 37.9 91 16 120.3 95 16
11 3.9 100 6 41.6 100 12 21.3 100 12



4.0 51 16
4.9 63 14
7.5 96 9
8.8 113 4
6.1 78 12
3.3 42 17
6.6 85 11
7.7 99 6
7.5 96 8
9.0 115 2
8.8 113 3
4.4 56 15
10.1 130 1
7.7 99 7
6.7 86 10
2.1 27 18
4.9 63 13
7.8 100 5

A.-Average measurements in millimeters.
B.-Relative measurements (check series, 100).
C.-Relative positions (greatest measurement, 1).
D.-Average positions.
Measurements December, 1913*.

Average positions based on stem length and leaf length and breadth, ar-
ranged for comparison with similar measurements from sand cultures with
citrus seedlings (1913, 1. c.). (Compare Tables 18 and 21.)

Acid B one
Phosphate Black

Sulphate of
Ammonia -- 11 12
Nitrate of Soda__ 7 13
Dried Blood --- 14 3
Nitrate of Potash 4* 8*
None ---------------- ---------
H. G. Sulphate
of Potash ------------------------

General Average- 9.0 9.0

Basic Phosphate Lime None General
Slag plus Lime Average

2 1 10 6.5
t ------ ---- 17 10.0
9 --------------------- 8.7
16* ----------------9.3
-- --------15 5 ---
------------ 6 --......

9.0---------- ----- ----

*All combinations include H. G. sulphate of potash except those marked
with an asterisk.
tIn numbering the positions noted here, the nitrate of soda-basic slag
combination has been omitted as it is not common to the two experiments.

Annual Report, 1914 xliii

Measurements June o1, 1913.

Average positions based on stem length and leaf length and breadth, ar-
ranged for comparison with similar measurements from pot experiments with
citrus seedlings 1914; measurements, December, 1913. (Compare Table 20).


Sulphate of
Ammonia --- 14
Nitrate of Soda- 9
Dried Blood -- 1
Nitrate of Potash 10*
None ----- ----
H. G. Sulphate
of Potash ------------

General Average- 8.5




Phosphate Lime None
plus Lime

3 7


5 .0 -- - --

11 17

...... 16



*All combinations include H. G. sulphate of potash, except those marked
with an asterisk.
tFla. Agr. Exp. Sta. Report, 1913, p. lii. In numbering the positions
noted here, the dried blood, acid phosphate and lime combination has been
omitted, as it is not common to the two experiments.


Florida Agricultural Experiment Station

Measurements made June, 1914.

Series Stem
No. Length


I 48.3 113 14
II 44.1 103 16
III 59.7 140 11
IV 38.0 89 18
V 69.0 162 7
*VI 67.0 1157 *
VII 92.6 '217 1
VIII 83.6 196 3
IX 89.3 '209 2
X 62.0 145 9
XI 60.0 141 10
XII 76.6 179 4
XIII 72.5 170 6
XIV 75.4 177 5
XV 66.7 156 8
XVI 59.3 139 12
XVII 52.5 122 13
XVIII 45.0 105 15
XIX 42.7 100 17



1.9 100
1.9 100
2.1 111
1.8 94
2.3 121
2.3 121
2.3 121
2.5 132
2.6 137
2.1 111
2.2 116
2.5 132
2.5 132
2.5 132
2.4 126
2.1 111
1.5 79
1.9 100
1.9 100

er Length

13 29.2 137 :
15 28.7 135
11 35.4 166
17 24.0 113 :
8 37.5 176
* 37.1 175
7 45.0 211
2 47.0 221
1 48.5 228
10 38.3 180
9 31.0 146
3 36.0 169
5 32.6 153
4 35.6 167
6 32.4 152 :
12 30.9 145
18 27.4 129
16 24.5 115
14 21.3 100



3.6 120 14
1.2 116 15
3.4 144 11
1.6 102 17
7.1 150 9
.8 147 *
1.0 184 3
L.4 188 2
2.1 194 1
7.2 151 7
3.0 140 12
3.8 165 5
7.7 155 6
).2 177 4
7.2 151 8
3.6 146 10
L.6 128 13
3.0 114 16
1.4 100 18



.68 110 16
.77 124 15
1.17 189 12
.48 77 18
1.52 245 7
1.60 258 *
1.98 319 4
2.04 329 2
2.40 387 1
1.40 226 10
1.25 202 11
1.90 306 5
1.51 244 8
2.02 323 3
1.60 258 6
1.49 240 9
.82 132 14
.88 142 13
.62 100 17

*This series was not taken into consideration when determining posi-
tions in order to make them comparable with those of the 1913 experiment
A.-Average measurements in millimeters.
B.--Relative measurements (check series, 100).
C.-Relative positions (greatest measurement, 1).
D.-Average positions.

Average Positions of Series.
(Compare Tables 22 and 24.)

Dissolved Acid
Acid Bone Basic Phosphate Lime None General
Phosphate Black Slag plus Limei Average

Sulphate of
Ammonia -- 13 15 11 6 12 11.2
Nitrate of Soda- 18 7 ----------- ------ 14 12.5
Dried Blood -- 3 2 1 4 ...... 2.5
Nitrate of Potash 9* 10* 5* ----------- ------------ 8 0
None ------------ ----------- ------------------------- 8 17 ---
II. G. Sulphate
of Potash -- -- -------------- -------------- ------ 16 ---

General Average- 10.7 8.5 5.6 _. -----...
*All combinations include H. G. sulphate of potash except those marked
with an asterisk.



Annual Report, 1914 xlv

Measurements, June, 1913.
Average positions based on stem length, stem diameter, leaf length, leaf
breadth and fresh weight arranged for comparison with similar measurements
from sand cultures with Citrus seedlings, 1914. (Compare Table 23.)

Dissolved Acid
Acid Bone Basi Phosphate Lime NoneGeneral
Phosphate Black Slag plus Lime lAverage

Sulphate of
Ammonia --- 16 14 7 8 13 11.3
Nitrate of Soda__ 10 9 ------ -- 15 9.5
Dried Blood -- 1 3 4 2 -- 2.5
Nitrate of Potash 11* 6* 5* ------- ------ --- 7.3
None ------------------- --- ---------------- 12 18 ---
H. G. Sulphate
of Potash --------------------- --------------- ----- 17 .-- --
General Average- 9.5 8.0 4.0 ----------- --------

*All combinations include H. G. sulphate of potash except those marked
with an asterisk.
tFla. Agr. Exp. Sta. Report, 1913, p. lii. In numbering the positions
noted here, the dried blood, acid phosphate and lime combination has been
omitted, as it is not common to the two experiments.
Plant Phys .iol-,.t.

Florida Agricultural Experiment Station

P. H. Rolfs, Director.
SIR: I hereby submit my annual report for the fiscal year end-
ing June 30, 1914.
THE WOOLLY WHITEFLY-Aleurothrixus howardi.
The major project of this department for the past year, has
been a study of this insect. As the results of this work will shortly
appear in a bulletin, extended reference to it here is unnecessary.

THE PINK FUNGUS.-In December, 1912, Prof. Rolfs found, in
a grove in Winter Haven, some Florida red scales (Chrysomphalus
aonidum) which were infected with a fungus. Although this fun-
gus was enough like the red-headed scale fungus (Sphaerostilbe
coccophila) in appearance to pass for that species to the eye of an
uncritical observer, to Prof. Rolfs, who has had long experience with
the entomogenous fungi of Florida, it presented an unusual look
which arrested his attention. Accordingly he brought it to the
station and turned it over to me for investigation.
Since our attention has been called to it, we have found it at-
tacking scale-insects on fruit and leaves from many places in Flor-
ida, ranging from Waldo in the north to Fort Myers in the south.
Such wide distribution in the State would indicate that the fungus
has been here for some time, but has been overlooked, and doubt-
less confused with Sphaerostilbe coccophila. .Nevertheless it is not
found in the majority of groves, and its introduction there would
seem to be well worth while, as our experiments indicate that it is
a very effective parasite of the troublesome red scale, at least during
the rainy season.
In April, 1913, some leaves showing this fungus were placed in
a basin of water, and into this were dipped the branches of some
small trees which were badly infested with the red scale. No par-
asitized scales were noticed until July, when the scales on one tree
were found to be well infected with the fungus. The infection con-
tinued to.spread over the station grove wherever the red scale was
to be found until checked by dry weather in November. This
fungus did much more thorough work in controlling the red scale
than Sphaerostilbe coccophila usually does against the purple scale.
If not checked by unfavorable weather it will kill all of the scales
on a leaf. This thoroughness is doubtless due to the character of


Annual Report, 1914 xlvii

the mycelium which spreads out radially in all directions and will
reach other scales at a distance of a half-inch or more. In this re-
spect this fungus resembles, though in a less degree, Aegerita web-
beri on whitefly larvae.
In appearance, this fungus differs from Sphaerostilbe coccophila,
to which it is evidently closely related, in its pinkish color, its more
widely spreading mycelium, and its choice of host.
Under a lens the pink color of the fruiting body is seen to be
due to the obscuring of the deep red color of the sporophore by
light-colored hairs which densely clothe it. In Sphaerostilbe coc-
cophila these hairs are absent or scanty, so that the deep red color
of the sporophore is unmasked.
The mycelium when well developed spreads out from the in-
fected scale and forms about the host a light-colored corona which
is absent or less developed in Sphaerostilbe coccophila.
While this fungus has been repeatedly observed growing on
the purple scale (Lepidosaphes beckii), especially when the latter
occurs mixed with Chrysomphalus aonidum, it does efficient work
against the latter only. With Sphaerostilbe coccophila the reverse
is true; it sometimes infects the red scale, but not nearly as readily
as it does the purple scale.
While we were engaged in making cultures and studying this
fungus, there came to us Vol. V, Pt. 3 of the Journal of the Agri-
cultural College of Tohoku Imperial University at Sapporo, Japan,
in which two Japanese botanists, Miyabe and Sawada, describe
what is apparently this species. Their fungus was collected in For-
mosa, on Chrysomphalus aonidum. Their reason for naming it
Microcera fujikuroi, instead of Sphaerostilbe doubtless was that
the imperfect stage only had been found. We have had no better
success in finding the perfect stage.
A number of packages of this pink fungus were sent out over
the State in November; but dry weather following put an end to
its multiplication on the station grounds, and doubtless prevented
an infection in at least a majority of the cases.
MICROCERA.-No further extensive work has been done with
this fungus, but a more or less close watch has been kept on its
progress out of doors. A marked epidemic of it was noted in Sep-
tember, thus adding additional weight to the opinion expressed in
the last Report, that it does its best work at that time and during
damp and rather warm weather in the winter.
DRY STORAGE OF FUNGI.-In the early part of December, 1912,
citrus leaves bearing abundant pustules of the red Aschersonia were

Florida Agricultural Experiment Station

collected from trees on the station grounds. These were carefully
dried for a week, and spread out on a table in the laboratory, in a
good airy place but out of the direct sunshine. They were then
piled in a box and kept in a dry closet until July, a period of seven
months. At the same time other leaves, collected from the same
trees, were put in a tight tin box which was placed in cold storage.
In July, both the dried leaves and the cold storage material were
stirred up in water in pans in which the twigs of whitefly-infested
citrus trees were dipped. In about three weeks we had secured an
equally good "catch" of red Aschersonia from the dried material
and from the cold storage leaves.
This experiment proves that, under favorable circumstances at
least, fungus material may be dried and the spores remain alive for
at least seven months. This is a matter of considerable importance
to the citrus grower, as fresh fungus material is liable to be scarce
in June at the time he most needs it for his trees. It is apt to die
out during the dry spells of winter and spring. Dr. Berger demon-
strated some years ago that it may be gathered in the fall when it
is abundant, and kept over in cold storage to be used at the begin-
ning of the rainy season. But few growers have cold storage fa-
cilities, and the discovery that it may be preserved dry will be of
considerable value to them.
Station Grounds.-The fungi kept the whitefly down fairly
well during the summer of 1913. No insecticides were used.
There was a light coating of sooty mold to be seen on some of the
trees, but the September brood was decidedly smaller than in 1912.
This partial control was due mostly to the brown fungus, although
there was considerably more of the red Aschersonia in September
than at the same date in 1912 The cinnamon fungus was less in
evidence. The growth of these fungi was stopped by a dry spell
in October, and another drought in May and early June reduced the
fungi to a minimum. The June brood of whitefly, however, was
not excessively large, on account of the rather thorough control.of
the fall brood. In late September the brown fungus set an exceed-
ingly heavy crop of spores, by far the heaviest I have seen. The


Annual Report, 1914

while the fall brood was still on the wing. Although there was con-
siderable new growth, it showed few adult whiteflies or eggs. This
was true even of the Satsuma trees, on which the growth of the
fungus is usually least satisfactory. In this grove, as in the sta-
tion grounds, there was more red fungus than during the previous
year, and the brown fungus set an abundance of spores. The grove
was well cultivated throughout the season, except in the summer,
but the very dry weather of the fall and especially spring caused
the trees to suffer greatly and throw off almost all the young fruit
resulting from a very heavy bloom. The drought also caused the
fungus to.almost disappear. By November 15 there was little fresh
fungus to be seen. There was, however, little whitefly left. But
the April brood of whiteflies, being nearly uninfested by fungi, was
able to increase, so that there is now much whitefly in the grove,
considerably more than a year ago. No insecticide was used.
Graves' Grove.-During the summer of 1913, the fungus, on
account of the scarcity of whitefly and the dry weather in the spring,
got a very late start. The grove, reinfested in the late summer
from chinaberry trees, became very black in September. The scanty
new growth was heavily infested. At that time there was much
red fungus, but less brown fungus than was the case the year be-
fore. Later, the brown fungus made good growth and so thor-
oughly cleaned up the fall brood that there was only a very light
infestation by June, 1914. There was hardly any live fungus at
this date.
Munroe and Stevens' Grove, Daytona.-This remained in quite
a satisfactory condition all of the year. As in the other cases, it
was chiefly the brown fungus that did the work. No insecticide
was used.
SUMMARY.-On the whole the summer of 1913 seemed more
favorable to the development of the red Aschersonia than that of
1912. There was also a good development of the brown fungus,
which set an exceptionally heavy crop of spores in late October.
The fall and spring were even more unfavorable than usual to the
development of the entomogenous. fungi. There was a prolonged
drought in October and November, and another (of nine weeks'
duration at Gainesville), from the middle of April to the middle
of June. As a consequence there is less fungus to be seen at this
date (July I) than at any time since the writer has been in the



Florida Agricultural Experiment Station

The experiments commenced in 1912 (see Fla. Rept. for 1913)
were continued during the summer of 1913. The difficulty of us-
ing the plain arsenicals on account of serious burning was indicated
in that Report.
The success of other stations in preventing burning with ar-
senicals by the use of lime-sulphur in the solution, led us to experi-
ment along this line. After many trials of different strengths of
each ingredient, we found that the following was about as strong as
could be safely used for August and September spraying on velvet

Commercial lime-sulphur solution --------------- I quart.
Lead arsenate paste ------------------- -8 ounces.
Water -------------------------------- --- 50 gallons.

By the use of the lime-sulphur in the solution we were able to
double the amount of the arsenical previously used without burn-
ing the plants. The lime-sulphur itself has been shown to be ef-
fective as a stomach poison for caterpillars.
By the use of this solution we were able to satisfactorily control
the caterpillars. As a result of the chemical action between the
lime sulphur and the arsenate, a black precipitate of polysulphides
is formed, which, if allowed to settle in the bottom of the tank, will
seriously burn the plants receiving the last portion from the tank.
To prevent this burning, and also the clogging of the nozzle and
pump, it is necessary to constantly agitate the liquid or else to strain
it before using.
Contrary to what one would expect, the older mature leaves are
much more easily burned than the younger ones. The leaves re-
main light green in color for some time after having reached full
size. They then gradually turn to a dark green and become stiffer.
It is these dark green leaves we mean when we speak of mature
leaves. Fortunately the caterpillars prefer the younger leaves so
that it is usually not necessary to spray the plants that are approach-
ing maturity. The formula given above did not seriously burn
even the mature leaves. This must be our aim in spraying, as there
will be some mature leaves on nearly all plants at the time the An-
ticarsia is at its worst, that is, in the latter part of August and the
first part of September.
Early Maturing Varieties of Beans.-Where early-maturing
and late-maturing varieties are planted near to each other, the early

.Annual Report, 1914

ones largely escape the ravages of the pest. Some notes were made
on September 9, 1913, at the station farm on a variety plot where
different varieties, or species, of Stizolobium were planted side by
side. There were three rows of each kind, and they stood in the
field in the order given in the table. Wakulla is a very early variety
originated by Mr. Belling, and matures at the same time as the
Yokohama, the earliest of the genus. Alachua, another selection
from a cross, matures one or two weeks earlier than the Florida vel-
vet, the latest of them all. The China bean matures about a month
earlier than the Florida.

Damaged by
Variety. Maturing. the Caterpillar.
Wakulla ------------Very early ----------Little.
Alachua ------------Late ----------------Considerably.
Yokohama ----------Very early ----------Very little.
Wakulla ----------Very early ----------Little.
Florida Velvet --------Very late -----------Heavily.
Wakulla ------------Very early ----------Little.
Alachua -------------Late ---------------Badly.
Wakulla ------------Early ------------Slightly.
Florida Velvet -------Very late ------------Very heavily.
Wakulla ------------Very early ----------Little.
Alachua ------------ Late ---------------Badly.
Yokohama .---.---- Early ---------------Slightly.
Wakulla ------------Early -------------Hardly touched.

Further observations were taken on the same day on adjoining
acre plots. The diagram shows the relative location, variety, and
amount of damage inflicted on some of these plots. With the ex-
ception of the one in the upper left-hand corner which was planted
later, these plots were planted on nearly the same day.
From these and other observations, we found that the severity
of the damage was directly proportional to the lateness of the va-
riety. We can safely say that if Chinese or other earlier varieties
are planted near Florida velvet or other late varieties, the former
will largely escape the ravages of the Anticarsia. That this would
be the case where an isolated patch is planted entirely to China
beans I am not so sure, but I am inclined to believe that the sever-
ity of the infestation would be less than if the same field was to be
planted to Florida velvet beans. A farmer could concentrate most
of the Anticarsia caterpillar on his farm by planting around the
edge of his field some Florida velvet beans, while the main crop
was the China or other early bean. The Florida Velvet could then
be readily sprayed.

Florida Agricultural Experiment Station









Osceola Volusia

On Sorghum





Diagram. Position of plots, and degrees of damage.
The Osceola is a month earlier than the Florida. The Volusia is probably
slightly later than the Florida and Lyon.
I. Damage scarcely noticeable.
II. Damage very slight.
III. Damage slight.
IV. Damage medium.
V. Damage considerable.
VI. Damage severe.

Birds are a very important check to the increase of this insect.
They collect on the infested fields in large flocks. The rice-bird is
one of the most important. We saw no evidence of the birds being
poisoned by eating the dead caterpillars. Where only a part of the
field was sprayed, the birds collected on the unsprayed portion even
when there were still numbers of live caterpillars to be seen on the
sprayed portion. A flock of turkeys should be a very important
check to the increase of Anticarsia.







Annual Report, 1914

Some observations and experiments were undertaken looking
towards the control of the tomato fruit worm, the worst insect pest
of the tomato in Florida. The control measures were along two
lines: the use of corn (especially sweet corn) as a catch crop, and
spraying with arsenicals.
Corn as a Catch Crop.-This idea was suggested by the ob-
servation that Heliothis was seldom observed to be injurious on to-
matoes when grown in gardens where sweet corn was also grown,
whereas it was always present as a serious pest where tomatoes
were grown on a commercial scale. Sweet corn was always severe-
ly infested.
In June, 1913, two days were spent about Webster, investigat-
ing the amount of infestation in fields and parts of fields next to
corn as compared with those removed from corn. These observa-
tions were continued about Rocky Point and Gainesville, in July,
1913, and June, 1914. Some representative results are given in
Table 26. They point, strongly to the conclusion that corn, partic-
ularly sweet corn, if planted near a tomato field, will protect the
adjacent tomatoes to a considerable extent provided that it is in
silk when the tomatoes are setting fruit. But when the silk be-
comes dry and the kernels hard, the insect prefers the tomatoes;
and, if left standing, this ripening corn becomes a center of infesta-
tion for adjacent tomato fields. To protect tomatoes from the to-
mato fruit worm, the corn must be planted at such a time as to be
coming into silk when the first tomatoes are forming. To secure
protection for the entire crop, one must have a succession of corn.
Spraying.-Some rather limited experiments were tried as to
the practicability of killing this insect by the use of arsenicals.
These have given promise of being quite successful. A priori one
would be inclined to the opinion that arsenicals would be of little
use, as the insects feed so largely inside the fruit. But some hab-
its of the larvae largely counterbalance this consideration. One
is their restlessness. They eat into one tomato, only to leave it soon
for another. This is more particularly true when the tomatoes are
small. In the field, injured tomatoes are apt to occur in groups
Observation has shown that in most cases where three or four ad-
jacent small tomatoes have been eaten into, it is the work of a sin-
gle caterpillar. As the tomatoes become larger, the worms are
apt to remain longer in a fruit.



Of Tomatoes

Webster--- June 10,'131About gone -----------
Webster--- June 10,'13,Full bearing --_- ----
Webster-_. June 10,'13 Full bearing ------
Webster--- June 10,'131About over --------
Webster--- June 10,'13 Too immature to pick-_
Webster--- June 10, '13 Just beginning to pick-_
Webster--- June 10, '13 Full bearing --------
Gainesville May 28, '14 Nearly ready for first pick_
Gainesville June 6, '14 Nearly ready for first pick-
Gainesville June 17, '14 Ripening ---------

Of Corn

Roasting ears --------
Full silk --------------
New silk to hard kernels
Roasting ears --------
Roasting ears -----------
Full silk ------------
New silk to hard kernels
Nicely in silk --------
Mature ---------------

Variety Crop on ground Distance to of
of corn previous year nearest corn Infestation

Field ------ Not known_-- Adjacent 7
Field ---. Watermelons __ Adjacent 5
Field ------ Not known---- Adjacent 3
Field ----- Not known--. 40 rods ----- 5
Field .-- Cotton ------- 40 rods---- 2
Field ---- Watermelons -- 80 rods------ 4
Field ---- Not known-- 40 rods----- 2
Field ------Watermelons --. 80 rods ------. 20
Sweet corn- New land-- 5 rods-- 0
Sweet corn, New land---- 5 rods-- 19
in same field

Locality Date

State of Maturity

Annual Report, 1914

Another habit that favors the control of this pest by means of
an arsenical spray is that of entering the tomato near the 'stem end,
the part of the fruit that is uppermost as it hangs on the vine and
therefore most apt to be covered with the poison.
It would probably be objectionable to spray tomatoes with an
arsenical during the picking season. Although the danger to the
consumer would be negligible, the presence of the insecticide would
doubtless hurt the sale of the fruit, and washing would be imprac-
ticable. However, on young vines, whose earliest fruits are no
larger than walnuts, there would be no objection, as the rains and
the rapid growth of the tomato would free it of the insecticide by
picking time. As the vines often need to be sprayed with Bordeaux
at this time, the arsenate could be mixed with this. In the home
garden there would be no objection to its continued use.

Icerya purchase has continued to spread with even greater rapid-
ity. The new infestations which have been reported during the
past year are given in Table 27.

Locality Date when first reported
St. Cloud ----------------------------------------August, 1913
Key West ----------------------------------------October, 1913
Odessa (Pasco County) -----------------------------January, 1914
Terra Ceia Island -------------------------------------January, 1914
Palmetto ----------------------------------------February, 1914
Leesburg -----------------------------------------February, 1914
Tavares -----------------------------------------March, 1914
Ashton -------------------- ---------------------March, 1914
Narcoossee ---------------------------------------- April, 1914

The infestation at Key West is a severe one. One correspond-
ent speaks of the scale as "devastating the vegetation." One of its
favorite host plants there is the "gumbo-limbo" (Bursera simaruba).
This is a new host plant.
The Station has been to considerable pains to facilitate the spread
of Vedalia to all localities infested with Icerya. The Vedalia
reached Leesburg apparently with, or very soon after, the Icerya,
as the first package of scales received from there contained the Ve-
dalia also.
Cylas formicarius, the sweet-potato root-borer, was sent in from
Larkin in March, 1913. It was long ago found in Florida (see

Ivi, Florida Agricultural Experiment Station

Insect Life, III, p. 334) but does not seem to be increasing at a rate
to cause alarm.
Hemichionaspis minor was found on the Station grounds infest-
ing Asparagus plumosus, apparently a new host plant.
Trirhabda brevicollis, a common chrysomelid beetle that fre-
quently defoliates prickly-ash and occasionally feeds on citrus, was
sent in in April, 1914, from Tallahassee, where it was "doing dam-
age" to pecans. The pecan seems to be a new host plant. This in-.
sect is unlikely to develop into a serious pest of pecans. It doubt-
less took to the pecans only after having defoliated the prickly ash.
Prickly ash should be cut down around all citrus groves and pecan
Aleurodes mori was found on March 3, 1914, at Gainesville,
infesting Euonymus americanus, a new host plant.

Annual Report, 1914


P. H. Rolfs, Director.
SIR: I submit the following report of the Plant Pathologist for
the year ending June 30, 1914.
During the year the work on citrus diseases has been carried
forward in accordance with the general outline, as far as practica-
ble. Chief attention has been given to Gummosis, Melanose and
Citrus Canker. Other diseases have been given such attention as
time and opportunity permitted.


Investigations along this line have been in the nature of field
studies, infection experiments and experiments for control. Ob-
servations on Gummosis have been made in a number of groves
throughout the State. A more critical study of the disease has been
made in a badly infected grove at Weirsdale, Fla., where a num-
ber of diseased areas were selected and have been kept under ob-
servation for more than a year to note the progress of their devel-
opment. Control and inoculation experiments have been inaugu-
rated in this same grove, and similar inoculation and control experi-
ments are in progress in another grove at Crescent City, Fla.
FIELD OBSERVATIONs.-Gumming of citrus trees is frequently
noticed in many of the groves throughout the State, and several
forms may be distinguished. A certain amount of gumming usu-
ally accompanies Foot Rot, and occasionally there is a slight gum
formation associated with Scaly Bark and Withertip. Small drops
of gum are often found oozing from minute cracks in twigs, from
cuts, wounds or other injuries in the tree; and this gum formation
is probably due to one or several species of fungi that are commonly
found in any citrus grove. Diplodia natalensis and Phomopsis citri
are known to cause gum to flow when introduced into cuts or
wounds made in healthy citrus bark (H. S. Fawcett, Fla. Agr. Exp.
Sta. Rept. for 1912, p. lxxviii).
Aside from the above forms of gumming, there is a typical dis-
ease known as Gummosis which occurs on the trunks and larger
branches of the citrus tree. Webber and Swingle mentioned the
disease in 1896 (U. S. Dep. Agr., Div. Veg. Phys. and Path., Bul.
8, p. 30) and Fawcett gave a brief description of it in 1907 (Fla.
Agr. Exp. Sta. Rept. for 1907, p. xlvi) and later called attention
to its increasing prevalence in the groves. It is not confined to any

Iviii Florida Agricultural Experiment Station

particular locality, but may be found in any citrus-growing section
in the State. In the northern portion of the citrus belt, the disease
is much more prevalent, and apparently increasing each year. Only
scattered cases of the disease have been found in groves in the south-
ern part of the State thus far visited.
Gummosis probably attacks all varieties of citrus. However,
no case has yet been observed on the sour orange (Citrus aurantium
amara). In some localities the grapefruit seems to be more sus-
ceptible, while in others the sweet orange varieties are more read-
ily attacked. The tangerine and Satsuma are sometimes severely
APPEARANCE OF THE DISEASE.-Gummosis occurs mainly on
the trunk and-larger branches of the tree. In some cases small twigs
are attacked. It is a bark disease, and is easily recognized by the
scaly, ulcerated areas formed in the bark, which are accompanied
with more or less gum flow. These diseased areas result from the
killing of the bark tissue in certain localized spots. This dead tis-
sue soon becomes infiltrated with gum, and hardens. As new tis-
sue is formed by the cambium, the dead tissue is pushed up in flakes
or narrow strips. These finally fall away, and the area apparently
heals, leaving a brownish resinous scar with a pitted irregular sur-
face. A copious flow of gum may be associated with the areas, or
the flow may be reduced to droplets oozing from small cracks at
the edges. The oozing of gum usually marks an active stage in
the development or spread of the diseased areas. As the progress of
the disease is arrested and the area begins to heal, the flow of gum
There are apparently two types or phases of Gummosis that
are frequently met with in the groves. Both are very similar in
general characters; but on comparing the two, certain differences
are noted that readily separate the two types.
Psorosis type.-One type may be referred to as Psorosis, the
name given to the disease by Webber and Swingle. No description
by which it might be recognized now is given of the disease they
had under observation at the time; but it is probable that this type
is the disease they had reference to. It is the same disease known
as Scaly Bark in California. It must not, however, be confused
with the Scaly Bark disease of citrus in Florida (Fla. Agr. Exp.
Sta. Bul. 106).
Psorosis attacks the trunks, larger branches, and even the small-
er twigs. It usually girdles the affected member, forming a zone

Annual Report, 1914

or band from a few inches to two or three feet in width. The sur-
face of the diseased area scales off in thin flakes, and the gum flow
is not so copious as in the other type. The gum occurs in drops
scattered over the surface, or oozes from cracks at the edges of the
infected band. The progress of the disease is up and down the af-
fected branch or trunk. New bark formed in the infected area is
much thickened, rough, and brownish. This gives the affected part
a swollen and ulcerated appearance. There is a continual breaking
out of new infections, and a subsequent healing, within the affected
This type is less common and apparently more severe than the
other type. So far it has not yielded to any of the methods of
treatment generally employed. The sweet orange varieties are ap-
parently more susceptible to this type, and the Navel and Valencia
seem particularly so. Only a very few cases of this type have been
observed on the grapefruit.
Gummosis type.-This type will be referred to simply as Gum-
mosis, for the present. It only occurs on the trunks and larger
branches, and is not found on the smaller twigs. A small spot or
definite area is formed, which.is a characteristic feature of the dis-
ease. In this type the bark is killed down to, and sometimes into,
the wood. Irregular patches of tissue, from one-half inch to several
inches in extent, may be killed. At first these are water-soaked, and
there is a copious flow of gum. Later, the dead tissue becomes in-
filtrated with gum, hardens, cracks, and the surface scales up in
large flakes or strips, as new tissue is formed from beneath. The
areas apparently heal, the scales or flakes of dead tissue falling away
and leaving a brownish scar with roughened surface. Usually the
disease at some future time breaks out again at the edge of the old
area. Spots from one-half inch to six or eight inches in diameter
many be found, and in many cases a number of infections coalesce,
forming an apparent girdling of the affected part. This type does
not form the distinct band or zone that is characteristic of the
Psorosis type.
Gummosis seems to attack all the varieties of citrus, except the
sour orange, with about the same degree of virulency. It is more
common than Psorosis, and is bceoming more prevalent and trouble-
some each year.
CAUSE.-The cause of Gummosis is not definitely known, and
probably several factors influence the development of the disease.
It is suspected of being caused by some fungus parasite, but investi-

Florida Agricultural Experiment Station

gations up to the present time have failed to reveal the cause or
throw much light on the nature of the disease. Several species of
fungi are found associated with active Gummosis infections. Some
have been isolated and inoculated into healthy citrus bark, but the
results obtained have not been conclusive. Gumming has been in-
duced in a number of cases, but the wounds soon heal with little
killing of the tissue. This may be due to the fact that the inocula-
tions, in a majority of the cases, were made in young citrus. trees
which seem to be, under normal conditions, more resistant to the
disease than older bearing trees.
Fawcett isolated Diplodia natalensis from a number of gum-
ming areas, and in the past season Phomopsis citri has been repeat-
edly isolated from infected areas. Many saprophytic fungi are
found to have invaded the infected areas, especially in the more
advanced stages of the disease. An examination of the diseased
areas throws little light on their cause.
ber of Gummosis areas have been kept under observation for the
past thirteen months, and notes have been made on the development
and changes that have taken place in these during that period.
Eighteen areas on orange and grapefruit trees were selected so as
to represent as nearly as possible the various stages in the develop-
ment of the disease. In size these varied from less than an inch to six
or eight inches in diameter, representing small incipient infections
with little gum flow, more advanced stages with scaly surfaces and
a copious gum flow, and older areas that had apparently healed leav-
ing a rough, brownish scar. The first notes were made in May,
1913, and subsequent notes were taken at intervals of three, ten and
thirteen months from that date. In the accompanying table the
condition of each area at the time of observation is indicated by the
following words: active, in which case there was recent killing of
tissue and more or less gum flow; healing, in which new tissue was
being formed, and there was little or no gum present; healed, in
which there was no gum present and the diseased tissue had sloughed
off leaving a brownish scar. The table merely illustrates the dif-
ferent phases that developed during the period of observation.
Of the ten active areas selected, five remained active throughout
the period, three had apparently healed at the end of thirteen
months, and two showed indications of healing, but became active
later. Of the eight areas that were apparently healed when select-
ed, four showed no change throughout the period, two became

Annual Report, 1914

active and remained so, and two became active for a time and then
showed indications of healing.


Area observation After 3 months After 10 months After 13 months
1 active active healing active
2 active active healing healed
3 healed healed active healing
4 healed healed healed healed
5 active active active active
6 active healing healed healed
7 healed healed healed healed
8 active active active active
9 active healing active active
10 healed active active active
11 active active healing healed
12 active active active active
13 healed healed healed healed
14 healed active active healing
15 active active active active
16 active active active active
17 healed active healing active
18 healed healed healed healed

Conclusions.-The behavior of the above areas indicates that
the disease is slow to develop, and that there are active and passive
phases associated with this development. These phases are, per-
haps, closely related to-variations in the resisting power of the tree
attacked. The citrus tree exhibits a certain resistance to Gummosis
as shown by the apparent or temporary healing of the infected
areas. The infection is apparently not entirely eliminated from the
tissues of the host, but invasion is checked, and the disease remains
quiescent for a time, perhaps encysted in a measure by the newly-
formed tissue. This probably marks the period of maximum re-
sistance on the part of the tree. When this resistance is lowered
by over-bearing, over-stimulation or other factors, these quiescent
areas again become active, and the new tissue is rapidly invaded,
usually at the edge or within the limits of the former area. Thus
the progress of the disease may extend over a period of years mark-
ing a contending struggle between the tree and the disease.
No doubt certain external factors are concerned in the develop-
ment of Gummosis, and when these are fully understood the prob-
lem of controlling the disease will be much easier of solution.
INOCULATION EXPERIMENTS.-Several attempts have been made
to transfer the disease to healthy citrus trees by inoculations. In

lxii Florida Agricultural Experiment Station

these experiments, diseased tissue from active Gummosis areas,
spores from pure cultures of Diplodia natalensis, and spores from
pure cultures of Phomopsis citri, were inoculated into healthy citrus
bark. Aseptic conditions were observed as far as possible in all
the inoculations, and checks were made in each series.
At first, inoculations were made in small potted trees under
greenhouse conditions; later, larger trees on the Experiment Sta-
tion grounds were inoculated; and finally inoculations were made
in large bearing trees in the grove. No definite conclusions can be
drawn from the results obtained in any of the following series of
inoculations, since in none of these were the characteristic areas of
the disease produced. In the young and non-bearing trees the re-
sults have been entirely negative in this respect. Gumming has been
frequently induced in them, but usually little or no killing of the
tissue has resulted, and no scaling or flaking off of the bark has
accompanied the slight infections produced. It may be that the
young trees are more resistant to the' disease than older bearing
trees. This is substantiated by observations in the field, Gummosis
rarely occurring on trees under seven or eight years old.
The results from inoculations into older bearing trees have been
a little more encouraging. Infections have gummed more freely
and much larger areas of tissue have been killed in most cases.
Typical Gummosis areas, however, have not yet developed from any
of the infections produced.
Other inoculations have since been made in bearing trees, but
sufficient time has not elapsed to report results.
The details of five series of inoculations made during the past
season follow.
Series I. Young Trees in Pots.-Inoculations were made in the
bark of young citrus trees grown in pots in the greenhouse. The
trees were small, the stems ranging from one-half to five-eighths
inch in diameter. The stems were thoroughly washed, wiped dry,
and again washed in a solution of mercuric chloride (I to o1oo)
previous to inoculation. Small incisions were made in the bark,
and a thin section of diseased tissue taken from an active Gum-
mosis area was inserted in each. The incisions were then closed,
and the stem wrapped with grafting tape, covering the inoculated
portion. Checks were made and treated in the same manner, ex-
cept that no tissue was introduced. Six trees were thus inoculated
on January 28, 1913, and the results of these inoculations are sum-
marized in the following table.

Annual Report, 1914 lxiii


Number of Results
Tree inoculations
A 4 Healed without gumming.
B 3 Healed without gumming.
C 3 Slight gumming in one cut, no killing of the tissue
Others healed without gum.
D 3 Healed without gumming.
E 3 cuts Check. Healed without gumming.
F 3 cuts Check. Healed without gumming.

The wounds had completely healed in one month after inocula-
Series II. Larger Trees in the Field.-In this series, inocula-
tions w-ere made in larger trees growing on the Station grounds.
The trees were from six to seven years old, with trunks three to
four inches in diameter. Two varieties of orange trees, sweet and
sour, were inoculated with thin sections of diseased tissue from an
active Gummosis infection. The same methods of making the in-
oculations were followed in this Series as were used in Series I. In.
oculations were made on March 7,. 1913, and the results are shown
in Table 30.


Number of Results
Tree inoculations
A Sweet 4 Healed without gumming.
B Sweet 2 Healed without gumming.
C Sour 2 Healed without gumming.
D Sweet 2 cuts Check. Healed without gumming.
E Sour 2 cuts Check. Healed without gumming.

The incisions were all healed in one month after inoculation.
Series III. Larger Trees in the Field.-This series is a repeti-
tion of Series II, except that the diseased tissue inoculated into the
trees was taken from the Psorosis type. Sweet varieties were inoc-
ulated, and checks were made on the same tree with the inoculations.
The trees were inoculated on April 2, with the results given in Ta-
ble 31.

lxiv Florida Agricultural Experiment Station


Number of Number of Results
Tree inoculations checks
A 2 2 All healed without gumming.
B 2 1 All healed without gumming.
C 2 2 All healed without gumming.
D 2 1 All healed without gumming.
E 2 1 All healed without gumming.

Series IV. Young Trees in Pots.-Spores from a pure culture
of Diplodia natalensis, and spores from a Diplodia isolated from a
decaying lime fruit were used in this series. The inoculations were
made in small potted trees in the greenhouse. Eleven trees with
stems about one inch in diameter were selected, and inoculated about
four inches above the crown. After introducing the spores into the
incisions, the stems were wrapped with oiled paper, covering the in-
oculated areas. These inoculations were made on September 6,
1914, and the results are summarized in Table 32.


No. of Number of Inoculated Remarks
trees inoculations with
4 4 Diplodia Gummed freely. No killing of the tis-
natalensis sue.
4 4 Diplodia Two gummed slightly. Two healed
from lime without gumming.
3 3 Checks Healed without gumming.

Six days after inoculation, three of the incisions into which
spores of Diplodia natalensis were introduced were gumming freely.
The other incision gummed slightly two weeks after inoculation.
There was no significant killing of the tissue around the point of in-
oculation, and in one month the gum had ceased and the wounds
were healed.
Of the four incisions inoculated with spores from the Diplodia
isolated from lime, two showed a slight gumming six days after in-
oculation, and two failed to gum. The incisions were completely
healed in one month from inoculation.
Incisions made in the check trees healed rapidly without gum-
Series V. Large Bearing Trees.-The inoculations of this
series were made in a bearing grove at Crescent City, Florida. A

Annual Report, 1914

number of trees in this grove were affected with Gummosis, and
this was very evident on a small block of grapefruit trees extending
through the center of the grove, which were badly attacked.
Four trees were selected for inoculation: three orange, and one
grapefruit. The orange trees were vigorous, healthy, and bore a
fair crop of fruit during the season. These trees were probably fif-
teen to eighteen years old, and they were entirely free from Gum-
mosis infection. The grapefruit tree was about the same size and
age as the orange trees. The main body of this tree had branched
near the ground forming three trunks, and on one of these several
active Gummosis areas were found. The inoculations were made
in the two healthy trunks.
Previous to inoculation, the trunk of each tree was washed thor-
oughly, wiped dry and then sprayed with a solution of mercuric
chloride and allowed to dry. Oblong cells of "Plasticene" were
then built up around the area of inoculation, leaving a small space
of bark surface exposed about a quarter of an inch wide and one
inch in length. The cells were about one-fourth of an inch in depth.
The interior of each cell was then sprayed with mercuric chloride
and wiped dry with sterilized absorbent cotton. A small deep inci-
sion was made through the exposed surface of the bark inclosed by
the cell, and the infecting material introduced into this under as
aseptic conditions as it was possible to obtain in the field. After
inoculation, the cells were sealed by pressing an ordinary glass slide
firmly against the exposed outer edge. These cells prevented the
rains or dews from washing outside contamination into the inci-
sions, a condition that can not always be avoided in the use of graft-
ing tape or oiled paper.
Tree No. I was inoculated with spores from a pure culture of
Phomopsis citri; tree No. 2 with mycelium from a pure culture of
Diplodia natalensis; tree No. 3 with thin sections of diseased tissue
from an active Gummosis area, and tree No. 4, the grapefruit tree,
was inoculated with the same material as No. 3. Checks were made
on each of the inoculated trees, and these received identically the
same treatment, except that no infectious material was introduced.
The inoculations were made on December 3, 1914. The trees
were banked a few days after the inoculations, and some of the cells
on the lower part of the trunks were covered with soil for a period
of three months. When the soil was removed, the cells were found
to be in good condition, and not to have been disturbed by the bank-


Florida Agricultural Experiment Station

The first notes were taken six weeks after the inoculations were
made. All the inoculations were not observed at this date, as the
banks had not yet been removed from the trees. The second notes
were made four and one-half months after inoculation, and all the
inoculations and checks were carefully examined at this time. The
results of these inoculations are given in Tables 33, 34, 35 and 36.


Six weeks. Not observed. Covered with soil.
Cell No. I. 41 months. Tissue killed for an inch around the point of
inoculation down to the wood; water-soaked, no gum.
Six weeks. Gumming; tissue killed an inch around point of
Cell No. 2. 41 months. Area spread somewhat; tissue killed to wood:
slight gumming, indications of scaling.
Cell No. 3. Six months. Healing, no gum
Check. 4% months. Completely healed.
Cell .No. 4. Six weeks. Not observed. Covered with soil.
Check. 4 months. Healed. No gum.
Six weeks. Gumming; tissue killed an inch or more around
N. the point of inoculation.
Cell No. 5. 44% months. Area has not increased in size; tissue dry, hard,
cracked; no gum, apparently healing.
Six weeks. Gumming; tissue killed an inch or more around
Cell No. 6. the point of inoculation.
ll No. 6. 4 months. No increase in size, inactive; tissue dry, hard,
cracked; no gum, apparently healing
Cell No. 7. Six weeks. Healing, no gum.
Check. 4% months. Slight infection has set in.


Annual Report, 1914



Six weeks. Not observed. Covered with soil.
41/2 months. Small area, less than an inch in extent. Slight
Cell No. I. gumming; tissue killed, surface bulging; beginning to
Cell No. 2. Six weeks. Healing, no gum.
Check. 41/ months. Healed.
Six weeks. Slight gumming; very small area of tissue
Cell No. 3. 4% months. Small area killed, less than an inch; no gum;
surface dry and hard, bulged, apparently healing.
Six weeks. Not observed. Covered with soil.
S 4% months. Small area of tissue killed about one-half inch
Cell No. 4. in diameter, not deep; slight gumming; surface bulged
and cracking.
Cell No. 5. Six weeks. Healing, no gum.
Check. 4/2 months. Completely healed.
Six weeks. Gumming, little killing of tissue.
Cell No. 6. 4% months. Small area killed; no gum; surface dry, hard.
slightly cracked, apparently healing.
Cell No. 7. Six weeks. Healing, no gum.
Check. 4% months. Slight infection has set in.
Six weeks. Slight killing of tissue around point of inocu-
lation, slight gumming.
Cell No. 8. 41/ months. Small area half inch in diameter killed, not
deep; no gum; surface dry, hard, apparently beginning to
scale off, healing.


Florida Agricultural Experiment Station


Six weeks. Not observed. Covered with soil.
Cell No. I. 412 months. Small infected area (less than an inch) at point
Gummosis tissue. of inoculation; tissue killed, water-soaked; no gum.

Cell No. 2. Six weeks. Healing, no indications of infection.
Gummosis tissue. 4% months. Healed. No gum.
Cell No. 3. Six weeks. Healing, no gum.
Check. 4% months. Healed, no gum.
Six weeks. Not observed. Covered with soil.
Cell No. 4. 41/ months. Small area about one inch around point of in-
Gummosis tissue, oculation; tissue killed down to the wood, brownish,
spongy, water-soaked; no gumming.
l N Six weeks. Slight gumming, apparently infected.
Cell No. 5i. 4% months. Slight killing of epidermal cells around point
soross tissue of inoculation; no gumming; healing.

Cell No. 6. Six weeks. Infection apparently beginning. No gumming.
CellPsorosis issue. 4% months. Slight killing of epidermal cells around point
of inoculation, healing; no gum.

Cel Six weeks. Apparently infected, slight gumming.
Cell No. 7. 4% months. Slight killing of epidermal cells, slight gum-
Psorosis tissue, ing; healing.
ming; healing.
Cell No. 8. Six weeks. Healing, no gum.
Check. 4% months. Completely healed.



Cell No. I. Six weeks. Infected, gumming
Check. 4% months. Gumming, little killing of tissue.
Six weeks. Gumming freely.
4%2 months. Slight killing of the tissue around point of in-
Cell No. 2. oculation; area about one inch, soft, water-soaked; gum-
ming freely.
Six weeks. Gumming freely
4%2 months. Tissue killed for more than an inch around
Cell No. 3. point of inoculation, down to the wood, water-soaked,
soft; gumming freely.
Six weeks. Gumming copiously.
4%/ months. Small area killed around point of inoculation,
Cell No. 4. less than one inch in extent, surface bulged; gumming
Cell No. 5. Six weeks. Healing, no gum.
Check. 4% months. Slight infection has set in.

Annual Report, 1914 lxix

CONTROL EXPERIMENTS.-Some preliminary experiments for
the control of Gummosis, conducted in a grove at Weirsdale, Fla.,
have been concluded during the year. These have brought out quite
clearly the importance of cutting out all diseased tissue from in-
fected areas before treating them with an antiseptic. The usual
practice among the growers throughout the State in treating this
disease, has been to merely scrape away the scales or flakes of dead
bark from the infected area and then apply some antiseptic.. Such
treatment has usually proved a failure in controlling the disease.
In cases where the diseased areas have been carefully cut away, and
all infected tissue removed, and some good antiseptic has then been
applied to the wound, good results have been obtained.
In this experiment, 76 trees were selected, with a total of 157
diseased areas in various stages. The experiment was divided into
6 series corresponding to the number of different preparations used
as antiseptics. Only one application of the antiseptic was made,
and the experiment extended through a period of ten months.
In one part of each Series the diseased areas were carefully cut,
all infected tissue being removed, and the wounds were then painted
over with the antiseptic. In the other part of each Series, only the
surfaces of the areas were scraped, all scale and flakes of dead bark
being removed. The antiseptic was then applied.
Table 37 shows the results obtained in this experiment.


Series Number of Method of Number
areas treated treatment healed
Bordeaux paste I -------------- 14 Cut out 9
24 Scraped 2
Bordeaux paste II -------------- 10 Cut out 0
14 Scraped 2
Lime and sulphur paste I ------ 11 Cut out 5
14 Scraped 0
Bordeaux paste II -------------- 9 Cut out 4
10 Scraped 0
Carbolineum; half strength --- 10 Cut out 6
11 Scraped 2
Liquid grafting wax ---------- 15 Cut out 2
15 Scraped 0

Florida Agricultural Experiment Station

The following preparations were used as antiseptics:
Bordeaux paste I.
Bordeaux paste II.
Lime and sulphur paste I.
Lime and sulphur paste II.
Avenarius' carbolineum (half strength).
Liquid grafting wax.

These results show that Bordeaux paste I was fairly effective.
Where the areas were carefully cut out before treating, 64 per cent
of the treated areas healed with one application of the paste. Bor-
deaux paste II was ineffective. Carbolineum (half strength) was
nearly as effective as Bordeaux paste I, in this case 60 per cent of
the treated areas healed with one application. The other prepara-
rations proved of little value as antiseptics with any promise for
treating Gummosis.
Bordeaux paste I. This was prepared by mixing equal parts of
a stock solution of copper sulphate and milk of lime. The stock
solutions were made up to contain one pound of the chemical to
one gallon of water in both cases. Freshly slaked lime was used in
preparing the milk of lime stock solution. After thoroughly mixing
equal parts of the above stock solutions, sufficient air-slaked lime
was added to the mixture to make a thin paste about the consistency
of whitewash. The mixture was applied with a brush.
Bordeaux paste II. This was prepared by mixing a dry Bor-
deaux powder (a proprietary brand sold under the name of Lig-
gett's Dry Bordeaux Mixture) with sufficient water to form a
Lime and sulphur paste I. Prepared by mixing three parts of
air-slaked lime with one part of flowers of sulphur in sufficient
water to make a thin paste.
Lime and sulphur paste II. The same as Lime and sulphur
paste I, only equal parts of lime and sulphur were used.
Carbolineum (Avenarius,). Diluted to one-half with water in
which soap had been dissolved at the rate of one pound to one
Liquid grafting wax. This was prepared according to the fol-
lowing formula:
6 ounces of alcohol (95 per cent)
I pound of rosin
2 ounces of tallow
I ounce of spirits of turpentine.

Annual Report, 1914

The tallow and rosin were melted together and then allowed to
cool. The alcohol was slowly added while stirring. The spirits of
turpentine were then added. This formed a thick viscid substance
resembling molasses in consistency.
Other experiments for control of Gummosis that are now in
progress are not sufficiently advanced to justify reporting at this
The work on Melanose during the year has been mainly a con-
tinuation of pruning experiments for control that were begun in
1913. In addition, Phomopsis citri has been isolated and grown
in pure cultures from citrus fruits affected with Stem-End Rot re-
ceived from twenty localities in the State. The results obtained
from infection experiments with these cultures are given in a fol-
lowing table.
An unusual development of this fungus in dead citrus twigs
occurred during the past season. Twigs and branches thickly stud-
ded with the pycnidia of this fungus were collected in several groves
early in December. In other groves visited later in the season a
similar condition was found to exist. This explains, in a measure,
the several severe outbreaks of Stem-End Rot that occurred in dif-
ferent localities during the season.
A press bulletin (No. 222) on Melanose was issued in April of
the present year calling the growers' attention to the importance of
pruning out the dead branches from citrus trees as an effective
means of controlling the disease.
PRUNING EXPERIMENTS.-These experiments were begun in
January, 1913, in a grove at Eastlake, Fla., which has suffered se-
verely from attacks of Melanose for several seasons past. The
object of the work has been to discover whether or not it was pos-
sible to successfully control the disease by carefully pruning out
all dead twigs and branches from the citrus trees attacked by Mela-
nose. The results of the experiment have been so encouraging that
the work will be continued through another season. Fifty-six
grapefruit trees were included in the experiment, and these were
divided into blocks of twelve and sixteen trees each. Block No. I,
of twelve trees, was not pruned but left as a check. Block No. 2
was pruned in January and again in June. Block No. 3 was pruned
in January. Block No. 4 was pruned in June. With the exception
of six trees in Block No. 3 the pruning was all done by ordinary
day laborers under careful supervision, and an effort was made to

Florida Agricultural Experiment Station

have them remove every visible dead twig and branch. Some dead
twigs were missed, but on the whole the pruning was thorough.
All prunings were removed from the grove and burned.
When the fruits were picked, the product from each block was
carefully examined and classed under four grades as follows:
Brights, seconds, russets and culls. With the exception of the culls,
these grades applied to Melanose spotting only, and no account was
taken of any russeting or staining produced by the rust mite or
other agencies. Under "Brights" were classed all fruits that were
entirely free from Melanose or showed less than I per cent of
the surface spotted. The "Seconds" included all fruits showing
from I to 25 per cent of the surface spotted. All fruits showing
from 25 to 75 per cent of the surface spotted were classed as "Rus-
sets." Under "Culls" were classed all unmarketable fruits and
those with surfaces entirely spotted.
Table 38 gives the percentages of the different grades from each

Block No. of When pruned Percentages of
trees Brights Seconds Russets Culls
No. 1 12 Check ------- 22 74 3 1
No. 2 16 January and June 46 49 1 4
No. 3 10 January --------- 39 50 2 9
No. 3* 6 January --------- 58 36 1 5
No. 4 12 June ----------- 33 59 3 5

*Pruned by the writer. Care was taken to remove even the smallest
dead twigs.

INFECTION EXPERIMENTS.-Citrus fruits showing typical cases
of Stem-end Rot were collected from twenty locations in the State
and pure cultures of Phomopsis citri were obtained from all of these.
Spores from these cultures were used in a series of infection ex-
periments in which Melanose spotting was produced on young suc-
culent citrus foliage. These infections supplement those reported
in the last Annual Report of the Station, and further substantiate
that Phomopsis citri is the cause of both Stem-end Rot and Melan-
ose. The spores from pure cultures were sprayed on the foliage, and
eighteen of the cultures caused Melanose spotting with the first ap-
plication. One failed to produce spotting after three trials, and
another did not produce sufficient spores to permit a trial.
Table 39 gives the locality and source of the cultures and the re-
sults of the infection experiments.


Annual Report, 1914


c a)
u 5 .


Aug. 8, 1913 St. Leo ------
Sept. 13, 1913 Blanton ---
Nov. 3,1913 Crescent City
Nov. 3, 1913 Maitland ---
Nov. 7,1913 East Lake-__
Nov. 7,1913 Weirsdale ---
Dec. 1,1913 Terra Ceia --
Dec. 7,1913 Palmetto ---
Dec. 12, 1913 Melrose ---
Dec. 28, 1913 Ft. Myers -_-
Dec. 31, 1913 Micanopy ---
Jan. 20, 1914 Tavares -
Jan. 22,1914 Palatka ----
Feb. 3,1914 DeLand ------
Feb. 7,1914 Lakeland --.
Feb. 10, 1914 Sutherland -
Feb. 10, 1914 Clearwater -
Mar. 12,1914 Bradentown -
Mar. 23,1914 Sarasota --.-
Mar. 23,1914 Manatee --


Sweet seedling
Sour orange
Rough lemon




*Weak culture.

This is a new disease that was called to our attention within the
past year. In April of the present year, a preliminary report was
issued describing the disease and giving such information as was
then available regarding its nature and distribution, and methods
for control (Fla. Agr. Exp. Sta. Bul. 122). Since the publication
of the above report the specific cause has been isolated, and more in-
formation has been obtained regarding its distribution, not only in
Florida, but in adjoining States. The disease was evidently intro-
duced into Florida on nursery stock. E. W. Berger, State Nursery
Inspector, states that as far as he can learn the disease was first
brought into the State in 1912 on a shipment of young Citrus tri-
foliata seedlings from Texas. Infections developed in this same
nursery in the following season. The disease was first recognized
by the writer in 1913, coming from a nursery near Miami. Later,
specimens were received from two nurseries near Monticello. In-


Florida Agricultural Experiment Station

spections during May and June in the southern part of the State
showed that the disease existed in 8 nurseries and Io groves in 6
Specimens of Citrus Canker have been collected by Dr. Berger
in Alabama, Mississippi, Louisiana and Texas. A specimen of the
same disease was received by B. F. Floyd from Japan, on peel and
leaves of citrus fruit. It was labelled "Scab" with which it was
evidently confused.
The disease has since been reported from Alabama by F. A.
Wolf and A. B. Massey, in Cir. 27, Ala. Agr. Exp. Sta., May, 1914.
Citrus Canker is caused by a species of Phyllosticta. (This is
evidently the same organism referred to by Wolf and Massey as
Phoma.) This fungus has been isolated from infections on grape-
fruit leaves, grown in pure cultures, and the characteristic infec-
tions of the disease have been produced with spores from these cul-
tures sprayed on young grapefruit foliage. The fungus fruited
readily in the infections thus produced, and it was isolated again
from them and grown in culture. It exhibited the same appearance
and growth characters in culture as the original organism from
which the infection was produced. The work on identification and
growth characters of the fungus has not been completed yet, and
a full report of these investigations will appear at some future date.
HosTS ATTACKED.-The grapefruit (Citrus decumana) and
Trifoliata (Citrus trifoliata) are very susceptible to the disease.
Other citrus varieties are occasionally attacked. Scattering infec-
tions have been noted on the foliage of the following kinds of
Navel orange (Citrus aurantium sinensis).
Satsuma (Citrus nobilis).
Lemon (Citrus ihedica limon).
Lime (Citrus medical acida).
Rough Lemon (Citrus medical hyb.?).
Owing to the absence of the assistant plant pathologist during
the past year, the work on vegetable diseases has received but little
attention. No active investigations were carried on in any of the
vegetable-disease problems. It is planned to take up this work
again this year and push it forward as rapidly as possible. There
is an increasing demand for information regarding the nature and
control of several serious diseases of vegetables common in the
State. Respectfully,
Plant Pathologist.


Annual Report, 1914


P. H. Rolfs, Director,
SIR: I submit herewith the report of the work in chemistry for
the fiscal year ending June 30, 1914.

CONDITION AND TREATMENT.-The improvement in the con-
dition of the trees, noted in last year's report, has continued. They
appear to be free from dieback, and have made a good growth this
The trees were fertilized in the spring and summer, the fall ap-
plication being omitted. The same amount of fertilizer was applied
at these times as has been customary in previous years. Culti-
vation has been followed in accordance with the original plan. A
fair stand of beggarweed was noted over most of the grove this
MEASUREMENT OF TREES.-In Table 40 is shown the increase
in girth of the trees of the different plots from 1909 to 1914, the
trees being calipered six inches above the bud.
Some rather interesting points are brought out on comparing
this table with the one published in the report for 1913. The two
clean-culture plots, 47 and 46, which ranked first and second in
1913, have this year been displaced by plots 2 and I. The most
notable gain in any of the plots was in plot I, which in 1913 ranked
thirtieth in the list, while in 1914 it ranks second. It is also of
interest to note that of the ten plots receiving the standard or half
the standard mixture without any added material, nine are to be
found in the first twenty-two plots, and six of these nine are in the
first ten plots.
It is also apparent that the plots receiving floats have not held
their own in the last two or three years. In 1912, the third and
seventh best plots were floats plots, in 1913 the third and eleventh,
and in 1914 the fifth and eighteenth. In this connection it will be
noted that of the sixteen best plots, fifteen received their phosphoric
acid in the form of acid phosphate. Whether this is due to any
superiority of the acid phosphate over other phosphatic materials
as a source of phosphoric acid, or to some peculiarity of the soil
on which the experiment is located, is, however, an open question.


Florida Agricultural Experiment Station



Fertilizer Treatment

2 60.3 Standard.
1 54.9 One-half Standard.
47 52.1 Nitrogen from dried blood. Clean culture.
46 52.0 Standard. Clean culture.
13 50.6 Standard. Mulched.
36 50.1 Phosphoric acid from floats (4 times the amt.). Cottonseed
41 48.9 Standard.
12 48.2 Standard and air-slaked lime.
37 47.4 Potash from low-grade sulphate.
45 47.4 Standard. Mulched.
48 46.5 Nitrogen from nitrate of soda. Clean culture.
22 46.1 Half nitrogen cottonseed meal, half sulphate ammonia.
30 44.8 Acid phosphate, nitrate of soda, hardwood ashes.
44 44.3 Standard.
21 44.0 Nitrogen from cottonseed meal. Ground limestone.
38 43.2 Potash from muriate.
43 42.7 No fertilizer.
35 42.4 Phosphoric acid from floats (four times standard).
8 41.9 Phosphoric acid and potash decreased by one-half.
9 41.9 Phosphoric acid and nitrogen decreased by one-half.
29 41.7 71/2 potash in June, 71/2 in October, 3 in February.
31 41.3 Standard.
23 39.9 Half nitrogen cottonseed meal, half nitrate of soda.
16 39.8 Half nitrogen nitrate of soda, half sulphate of ammonia.
32 39.7 Phosphoric acid from dissolved bone black.
42 38.5 Potash from nitrate of potash. Balance nitrogen nitrate of
25 38.1 Phosphoric acid from steamed bone.
24 37.8 Phosphoric acid from dissolved bone-black.
20 37.6 Nitrogen from cottonseed meal.
11 37.5 Standard and ground limestone.
6 36.9 Phosphoric acid and potash increased by one-half.
39 36.7 Standard and ground limestone.
34 36.3 Phosphoric acid from floats (twice standard).
33 35.4 Phosphoric acid from floats.
26 35.3 Phosphoric acid from steamed bone (twice standard).
15 35.2 Nitrogen from nitrate of soda.
7 34.1 Nitrogen and potash increased by one-half.
3 33.8 Twice standard.
19 33.0 Half nitrogen from nitrate of soda, half from dried blood.
10 32.7 Nitrogen and potash decreased by one-half.
14 31.8 Standard.
40 27.9 Potash from kainit.
17 27.8 Nitrogen from dried blood.
27 27.4 Phosphoric acid from Thomas slag. Nitrogen, nitrate of soda.
18 25.7 Half nitrogen from sulphate ammonia, half dried blood.
28 23.5 Phosphoric acid, Thomas slag (double amt.). Nitrate of soda.
5 21.6 Phosphoric acid and nitrogen increased by one-half.
4 15.8 Four times standard.


Annual Report, 1914

Below is given the average diameter of the 480 trees of the
grove for every year since they were set out:
The average diameter in 1909 was 22.5 thirty-seconds of an inch.
" 1910 26.9 " "
." 1911 36.6 "
.. 1912 46.7 .
S 1913 56.7 "
S1914 62.1 '
FERTILIZATION.-The trees in battery I have been fertilized
three times a year as usual, and with two pounds at each appli-
Those in battery 2 received one pound at each application, the
trees being young and of small size. (The character of the ma-
terials used may be ascertained by consulting previous reports.)
RAINFALL AND DRAINAGE.-The rainfall for the period from
April I, 1913, to April I, 1914, was 49.14 inches. Of this amount
12.7, inches, or 25.9 per cent, was collected as drainage water from
the tanks in battery I, and 24.53 inches, or 49.1 per cent, from the
tanks in battery 2. The trees in battery 2 have not made sufficient
growth yet to influence the amount of water leaching through the
are given the data representing the composition of the drainage
water collected during the last year.
By referring to" Table 41 it will be noted that the losses of
potash have continued to increase, being considerably larger than
for the same period the year before. Just the opposite is noted with
reference to nitrogen. Here the losses are decreasing. Tank 2
shows the largest losses of this constituent. This is probably ex-
plained by the fact that the tree in this tank did not make as vigor-
ous a growth as did the others, and consequently used up less of the
nitrogen present. The losses of lime continue large. The fact
should be noted, as has been already pointed out in a previous re-
port, that in tank 3 the losses of lime are considerably under those
from the other three tanks. The explanation, that the presence of
another alkaline material, namely, soda, serves to prevent loss of
lime to some extent, seems to agree with the facts.
The presence of comparatively large amounts of ammonia as
such, in the water from tanks I and 2 collected on March 6, is of
interest, and indicates that a portion of the sulphate of ammonia ap-
plied leached through without being nitrified.



Florida Agricultural Experiment Station

In Table 42 the data given do not vary in any great degree
from the results reported last year for this battery. It is only in
the last two collections of water that the presence of a portion of the
fertilizer in the water is noted.


April I, 1913, to April I, 1914.

C7 02
Z E3
%fS iz "
Fl S ^- c

July 14 ----- 116.5
Oct. 31 ----- 112.2
Jan. 3 --------- 112.2
Jan. 24 --- 112.0
Feb. 11 -----------106.2
March 6 ------113.2


.10 .0 60.7
.13 .01 99.6
.16 .04 67.4
.10 22.5
.10 .01 24.2
.93 .01 30.9

16.9150.8 21.6 56.0 15.41 28.7
15.1216.0 28.2 90.0 46.8 23.3
13.02150 32.6143.0 55.4 29.0
9.2172.5 39.4 66.6 29.2 14.8
12.5 183.5 25.9 65.8 25.7 21.2
16.7222.5 25. 73.0 27.5 16.6
I I 1_______


July 14 ------------582 .19
Aug. 9 ---------102.0 .31
Oct. 31 --------- 106.3 .24
Jan. 3 109.8 .3
Jan. 24 ------ 110.0 .17
Feb. 11 -------104.5 .10
March 6 --------11242.2

.04 74.2 246.0
* 149.9 586.5
.04 2542 841.9
* 30.4739.5
.01 12.9511.8
* 25.7471.7
.02 22.3411.7


32.2316.7 27.6102. 32.9
26.9452.5 34.6260.0 65.2
12.3257.0 28.9250.8 68.9
8.3 196.0 24.2 129.1 29.3
8.8225.0 18.4 83.3 21.4
13.203.5 17. 56.8 39.9
,1 1.29 56.


July 14 ------92.5
Oct. 31 -- -- 107.2
Jan. 3 ------- 108.4
Jan. 24 ------109.01
Feb. 11 -- -------107.2
Mar. 6 ------111.8

.1 .04113.25264 289 94.6
.08 90.0 681.4 160.3 164.5
.17 17.3515.1 39.9119.0
.0 .01 12.1432.6 39.2112.5
.0 .01 34.1249.0 19.6 68.0
.06 .03 36.9243.6 23.2 79.0
Ik1 I

20.4 71.4217.4 43.9
30.4158.8343.3 34.9
23.5207.5144.0 34.0
35.3134.51108.0 22.3
16.4104.3 55.2 21.8
264 91.4 73.3 21.4

July 14 -------- 88.5.22
Oct. 31 ------------ 37.9 .14
Jan. 3 ------- 42.0 .28
Jan. 24 ------ 113.5 .15
Feb. 11 --- --- 117.4 .14
Mar. 6 -------- -116.2 .10


.01 13.365.0 26.0180.2 44.4 77.6 34.3 41.4
* 25.7420.6 22.4 156.0 38.0 83.3 71.7, 41.3
* 16.1 80.0 63.5240.0 93.8158.6 120.9 33.2
.01 10.6556.7 25.6198.0 72.71 96.5 64.2 18.8
* 12.3583.0 17.4218.5 72.5115.5 38.6 24.0
* 12.686.7 19.9205.0 49. 87.6 30.9 29.2



- U



Date g S z


July 8 ------
July 21 ----------
Aug. 7 --------
Aug. 26 ----------
Sept. 22 -------
Nov. 28 ------
Jan. 3
Jan. 24 ------------
Feb. 11 -------------
Mar. 6 -----
Apr. 1

July 8 --- -------
July 21 -------------
Aug. 7 ----------
Aug. 26 ----------
Sept. 22 ----------
Nov. 28 -------------
Jan. 3 -
Jan. 24 --------
Feb. 11 -
Mar. 6 -------------
Aur. 1

.02 18.6 7.0
.0 53.0 4.5
.02 40.0 5.1
.03 32.4 5.4
.02 12.7 6.7
.01 6.5 8.8
* 15.8 5.5
* 24.2 5.3
.01 10.9 7.4
* 7.7 7.1
.01 2.0 6.3

.01 25.4 6.1
.02 37.9 4.4
.02 36.2 5.0
.02 46.3 4.0
.04 37.7 4.3
* 9.9 5.9
.01 20.7 5.1
* 31.9 4.8
* 15.1 6.7
* 17.3 5.8
.01 72.5 33.4

5.2 10.9
6.1 17.9
4.6 14.3
3.2 12.9
2.6 8.7
3.7 6.0
3.2 8.2
3.6 7.0
1.8 5.9
2.4 7.0
2.1 6.9

5.5 9.0
5.9 11.3
4.1 10.0
3.9 10.8
5.3 11.2
2.6 6.3
3.4 8.4
3.3 7.9
1.7 5.1
8.7 10.3
7.8 43.7

3.0 14.2
3.2 15.9
2.9 15.4
3.7 18.1
3.4 17.1
2.9 9.2
3.9 17.5
3.0 10.7
2.2 7.8
3.9 9.5
15.3 21.7

5.2, 31.5
5.0 19.7
5.8 23.3
5.9 23.2
6.1 25.8
5.9 34.6
5.4 18.7
3.2 12.5
3.5 13.3
5.3 14.5
7.1 22.7


July 8 --------------116.0 .07 .02 31.1 5.2 6.1 14.5 5.7 2.7 3.7 13.4
July 21 -------------138.6 .10 40.8 4.1 6.0 16.6 6.0 3.4 5.8 10.9
Aug. 7 --------- 116.1 .04 39.1 4.3 4.5 14.5 5.4 3.4 4.8 15.7
Aug. 26 -------------123.4 .06 .03 36.6 6.0 3.4 14.8 6.7 3.5 5.4 13.2
Sept. 22 -------------118.9 .06 22.2 5.2 2.8 11.1 4.6 2.7 5.0 15.0
Nov. 28 ------------ 83.1 .03 12.6 7.4 1.7 8.1 4.4 2.5 6.6 23.0
Jan. 3 ------126.0 .11 19.5 5.6 3.4 8.7 3.7 6.8 4.7 11.5
Jan. 24 -------- 116.0 .12 15.3 6.8 1.8 6.9 3.4 2.0 2.7 9.8

Mar. 6 -------- 121. .08 03110.8 14.1 27.5 46.3 19.4 3.2 19.4 9.3
Apr. 1 97.2 .18 37.8 33.2 15.4 30.1 12.1 3.8 21.6 21.7

July 8 -------123.0
July 21 ----------- 1213
Aug. 7 116.3
Aug. 26 104.
Sept. 22 -------123.4
Nov. 28 ----- 84.2
Jan. 3 ----------- 126.4
Jan. 24 -------- 120.
Feb. 11 ------------123.4
Mar. 6 --------1123.
Apr. 1 ---- 101.3

.02 28.6 5.6
.02 43.1 4.4
.03 33.8 4.8
.01 39.8 4.6
.04 22.6 6.0'
.01 8.7 9.6
.01 14.2 6.9
.01 25.2 6.0
.02 15.1 7.2
.0224.7 6.5
.02 71.3 28.4

5.2 10.8 7.2
6.0 13.3 9.9
3.7 10.8 7.7
2.0 113 8.5
2.1 9.0 6.6
1.6 3.8 4.6
3.2 73 5.0
3.0 6.9 5.7
2.3 5.1 4.3
7. 11.3' 7.7
7.4 34.7 27.1

4.2 16.9
4. 13.6
4.3 20.0
4.9 18.9
4.8 19.4
5.6 23.5
5.4 12.7
2.5 7.9
2.8 9.1
4.1 10.6
6.9 18.4

lxxx Florida Agricultural Experiment Station

During the year a number of samples of Japanese-cane juice
have been tested for sucrose content, for the department of animal
industry and horticulture.
The analyses of a number of samples of Japanese cane, taken
from the fertilizer plots of the department of animal industry, have
been nearly completed.

Annual Report, 1914

P. H. Rolfs, Director,
SIR: The following is the report of the assistant botanist for
the year ending June 30, 1914.

About an acre was planted in 1913 with 21 families of the third
generation of the Lyon by Florida Velvet cross. These were more
or less early plants, and had long pods covered with fine' down or
with velvety tomentum. Most of these downy second-generation
plants gave in the next generation about one-quarter of black plants
which were later than the downy plants of the same family. Many
of the families also had about one quarter with short pods. Nine-
teen of these third-generation plants have been selected, and 25
seeds of each sown for the fourth generation. One very early
plant, LV-92, has some descendants which are especially promising,
having larger vines than other early plants. -
Ten plants of the first generation of the Florida-by China cross
were grown in 1913. An acre has been planted with 600 seeds from
Nearly an acre was planted in 1913 with 480 seeds of the second
generation of the Florida by Yokohama cross. On account ,of
drought, about half had to be resown. All the seeds came from one
first-generation plant. There were many early plants, but few
were promising. Five were selected, and 25 seeds of each planted
in the spring of 1914. The coarse pubescence, thick hull, and
small seeds of the Yokohama are undesirable characters, and have
to be avoided in these selections.
Seeds of an upright Stizolobium (S. stands) have been received
from Africa through the U. S. Department of Agriculture. The
young plants have been set out, and attempts will be made to cross
them with the Florida, and with some of the constant early strains
from the crosses.
In 1912, a single healthy small dwarf plant appeared in a second
generation family of nearly 600 plants. The progeny of this dwarf
plant grown in 1913 showed however that its dwarfness was not
inherited. (A few dwarf plants with yellowish rounded leaflets ap-
peared in the second generation of all the crosses, but these set no
Several families of the so-called "white" Florida Velvet bean,
and of VL-Ic, which resembles it in seed mottling, were grown in


Florida Agricultural Experiment Station

;C '
.. ~

FIG. 5.-Osceola bean with full-sized pods and falling leaves,
on September 19. Scale in feet.


.. .. I



Annual Report, 1914 lxxxiii

FIG. 6.-Florida velvet bean in flower, on September 19. Scale in feet.


Florida Agricultural Experiment Station

1910, 1912, and 1913. The results showed (as Tschermak, 7, and
Fruwirth, 3, have found in peas) that white-seeded plants may
throw mottled ones. A further investigation of this is being made.
A large tract of land was planted with different families of the
fifth and sixth generations of VL-515-27. An examination showed
that no black plants appeared. This new bean has been named
"Alachua." It is regarded as suitable for South-central and South
Families of the fifth generation of VL-216-I, VL-515-27, and
VL-297-II, were grown on the Station farm, together with Flo-
rida Velvet and Yokohama, in plots of Iooo square feet. An ac-
count of these is given in the report of the animal industrialist.
The highest yield was given by the families of VL-216, which aver-
aged between 37 and 49 bushels of clean seed to the acre, 67 pounds
to the bushel. This new bean has been named "Wakulla." It has
matured well in North Carolina.
'Different strains of VL-297 grew well in 1914. (In 1913 they
were cut down by caterpillars.) When planted as early as possible,
they may escape the caterpillars. This new bean is a month earlier
than the Florida, and has been named "Osceola." It is regarded by
Prof. S. M. Tracy, who has grown it for two years at Biloxi, Mis-
sissippi, as suitable for Mississippi. I consider it a promising bean
for North and Central Florida. Figs. 5 and 6 show typical plants
of Osceola and Florida Velvet respectively on September 19.
An increase in size of internodes or leaves, and increased
rapidity of growth in first-generation hybrid plants has been as-
cribed; (a) in peas, to the combination of definite growth factors
[Keeble and Pellew (4), Relander (5)], and (b) in maize especial-
ly, to the heterozygous state of genetic factors [Shull (6), East and
Hayes (2)]. When the parents are of nearly the same size, as is
the case with the Florida and Lyon, the first hypothesis accounts
for the presence in the second generation of plants larger than or
equal to the parents, and also of several grades of plants smaller
than the parents, some of which sizes can be bred to constancy in
further generations. Since this happens in the Florida by Lyon
cross, it may be assumed that the increase of internode and leaf size
and of rapidity of growth in the first generation hybrids is chiefly
due to the combination of different growth factors. For, purely
on the second hypothesis, none of the different sizes could be bred
to constancy.


Annual Report, 1914

Thus in the crosses of the Florida and Lyon, the plants of the
first generation grew off so much more quickly than either parent,
and had such large leaves, that the effect was striking to all ob-
servers. In the second generation, nearly 600 seeds were started
in pots, and, when their first leaves had expanded, were planted out
in the field in order from north to south. The plants on the north,
though here and there they included small early plants, made on
the average a stronger growth than those on the south, and often
had very large leaves. Some of these rapid growers equalled or
exceeded the first-generation hybrids. The largest plants were
late in flowering. Only one of these late strong growers was raised
in the third generation, and most of the 12 plants of the progeny
apparently equalled their parent. Several of the smaller second-
generation plants were grown, and constant lines bred, which (i)
would only climb to the top of a ten-foot pole, or (2) grew to
about half the size of the Florida or (3) equalled the Florida.
In the cross of the Florida by Yokohama, a large plant, with
vines 30 feet or more long, is crossed with a small plant which will
barely climb 8 feet. The 1 first-generation plants could not be dis-
tinguished in growth from adjacent plants of the Florida. The
second generation gave a majority of large and intermediate plants,
and a minority of small ones; but, on account of the effects of
drought, no accurate count could be made.
The plants of the first generation of Florida by China (Fig. 7)
exceeded the Florida in i cpidity of growth. They did not appear to
grow so rapidly as the first generation of Florida by Lyon.
It was shown, in the Report for 1913, that size of plant de-
pends in great part (but not wholly) on time of flowering; for when
a plant has set a full crop of pods, further growth stops. Hence
the main factors for size of plant are the same as (or are linked
with) those for late flowering. At least five main genetic differ-
ences appear to affect the size and lateness in the cross of Florida
Velvet and Lyon, two of which (B and D) are also known to af-
fect the pubescence (see below).


The Florida Velvet bean has a pubescence of whitish stiff hairs
on its leaf-buds and young shoots. This can also be readily seen on
the surface of the full-grown leaves. Sometimes, especially in cool
weather in the fall, the pubescence is in part brownish. A similar
stiff pubescence occurs on the calyx, except for a patch of brownish-


Florida Agricultural Experiment Station

black tomentum on the back.- The ovaries and young pods are
covered with long silky soft hairs, which soon turn black and re-
semble black velvet. The ripe pods are covered with a brownish-
black tomentum of twisted flattened hairs mixed with a few stiff
hairs. These hairs average one millimeter or more in length.
Plants resembling the Florida Velvet bean in all these particulars
are here said to have "velvet" pubescence.
The Lyon bean has a whitish stiff pubescence on its young
shoots, leaves, and calyx. The pods are covered with a fine ap-
pressed down of whitish hairs, averaging up to half a millimeter
long, and giving a grayish appearance to the ripe pod.
The hybrid plants of the first generation have whitish or yel-
lowish pubescence on their shoots, leaves, and calyxes, with some-
times also long yellow bristles on the calyx. Their pods are thickly
covered with sharp stiff appressed bristles, averaging about one
and a half millimeter long. These contain a gummy substance in
the hollow points, and readily pierce the human skin, causing an ir-
ritation which may last a few minutes. The dry hairs several years
old seem to sting as much as those from the fresh pods. These
stinging bristles are readily detached, and come off in a cloud when
a plant with dry pods is shaken. The hybrid pods are usually yel-
lowish on the side exposed to light, and gray on the reverse.
In the second generation, about nine-sixteenths of the plants
have stinging pods. Many of these pods have stripes of red bris-
tles, such as only occur at the bases of the pods of the first-genera-
tion hybrids. Some have brownish-yellow or straw-yellow bris-
tles, and some gray; in some the bristles are more erect; and a few
sting more strongly than the first-generation plants. Thus there
are several classes of stinging pods, but no enumeration of them has
been attempted. About three-sixteenths of the second-generation
plants have black tomentum on their shoots, leaves, bracts, and
calyxes, as well as on their pods. These are divided into two classes;
one with long tomentum, averaging about a millimeter, on the pods;
and the other with pods which appear nearly glabrous, but which
have, at least when young, a fine black tomentum, the separate hairs
of which may measure up to half a millimeter. In both these classes
there are some plants in which the tomentum is lighter in color or
more or less mixed with whitish stiff hairs. About 'one-sixteenth
of the second generation are "velvet" plants; that is they have stiff
whitish pubescence on shoots, leaves and calyx; except for-a patch
.of-black tomentum on the calyx; and have long brownish-black
tomentum-on their pods. In most of these, stiff whitish hairs' are

. xxxvi

Annual Report, 1914



Stinging Downy Velvet Black Reces've

P V ------------------ ------------------ X ... -
L ------------------ -- -------- X ----------

F1 V by L -------------- -- 7--- --- -

P VL ---------------- -- 161 40 15 62 ?

VL-515 downy --------
VL-467 downy -------
VL-509 downy --------
VL-216 downy -------
VL-480 velvet --------
VL-297 black ---------
VL-437 black ---------

VL-515-27 downy -----
VL-515-1 downy ----.
VL-515-21 downy ------
VL-515-22 downy -----
VL-515-23 downy ------
VL-515-31 downy ----.
VL-515-35 downy -----
VL-216-1 downy -----
VL-480-6 velvet
VL-297-19 black
VL-297-12 black -
VL-297-23 black --

VL-515- 1-1 black ---
VL-515-27-1 downy ---
VL-515-27-2 downy ----
VL-515-27-4 downy --.
VL-515-27-8 downy ---
VL-515-27-35 downy ---
VL-515-27-38 downy ---
VL-515-27-40 downy ---
VL-515-27-49 downy---
VL-515-27-54 downy---
VL-515-27-55 downy ----
VL-515-27-62 downy --..
VL-515-27-64 downy ---
VL-216- 1-17 downy -----
VL-216- 1-27 downy ---.
VL-216- 1-28 downy ---.
VL-216- 1-35 downy ---.
VL-216- 1-26 downy --..
VL-297- 5-21 black ---
VL-297-11-12 velvet ----
VL-297-11-14 velvet ---
VL-297-11-22 velvet --...
VL-297-11-16 velvet --...
VL-297-11-2 velvet ---
VL-480- 6-23 velvet ---
VL-480- 6-11 recessive --



12 -----

--5 -----
15 -----

51 --- ---
10 ----- 4 ----
---- 22 ---------- 14
--- 37 ---------- 11
--- 29 ---------- 11
--- 28 --------- 9
----- 31 ----- 8 ---
28 -- - --
------ 20 -----9--- 9
---- ---- ------- 35
------- 2 10
------- 15 23




-- ----

-- --

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





lxxxviii Florida Agricultural Experiment Station





P L --------------------- ---------
V -------------------- ---------

F1 L by V ---------------. 6

F2 LV --------------------. 320

F3 LV-113 downy-------- -------
LV-91 downy -----------------
LV-311 downy---------------
LV-92 downy ----------------
LV-279 downy --------------
LV-548 downy --------------
LV-569 downy---------- ----
LV-114 downy _------- ---_--
LV-468 downy ------- ------
LV-527 downy-------- -_----
LV-558 downy -----
LV-27 downy -------------
LV-461 downy ---- ___
LV-80 velvet ---
LV-310 velvet
LV475 velvet
LV-392 velvet
LV-486 black
LV436 black
LV-206 black ..

Downy Velvet Black

--------- -- X
- ---------- -- -----
.. .. .. .. -
- - - - - - -


34 102




mixed with the black tomentum on the pods. The remaining three-
sixteenths of the second generation have stiff whitish or yellowish
pubescence all over. This may be as fine as on the Lyon pods and
only half a millimeter long; or may be coarser, up to three-quarters
of a millimeter; and in a few plants the hairs on the pods may be
one millimeter long. These three classes are, "fine downy," "coarse
downy," and "intermediate" (between stinging and downy); but
the boundary between the first two cannot be sharply drawn. (Some
fine downy plants gave a minority of coarse downy in their progeny,
and some fine and coarse downy plants gave an occasional interme-
diate. One second-generation intermediate had constant progeny.
Some -second-generation fine downy plants have been constant to
the sixth generation. No fine downy plants were found among
the progeny of typical coarse downy parents.) In the third gen-
eration, certain plants were- found whose pods had coarsish ap-
pressed hairs, and whose calyx had a patch of black tomentum.



Annual Report, 1914 lxxxix

These are called "recessive downy" plants, because they appeared
as recessives in "velvet" families. None of them were certainly seen
in the second generation (but in some of the downy plants of this
generation the calyx was not observed). One recessive downy
plant was seen however in the second generation of the Florida by
China (see below).
In the second generation, a minority of the downy, as well as
of the stinging plants had erect hairs; and a minority of stinging,
downy, velvet, and black plants had sparse hairs thinly scattered on
the pods. No counts of these were made.
(In table 43 the letter X stands for several hundred or thousand
plants in field culture.) All these plants were grown eight feet
apart, except the third generation of VL-48o and VL-216, and
most of the fifth generation.
In the second generation of the Velvet by Lyon cross there were
38 white plants which set no pods, so that it could not be told
whether they were stinging, downy, or velvet. The total of plants
with white shoots was 254, and those with black shoots numbered
62. The calculated number are 257 and 59. Hence we have, al-
lowing for the 38 white plants with no pods:

Stinging. Downy. Velvet. Black.
VL -------------------- 161 40 15 62
(Calculated -------------- 149 : 50 17 : 59)
In the reciprocal cross we have 469 white to 102 black. The
calculated numbers are 464 and 107. Hence, allowing for 8 white
plants that bore no pods, we have:

Stinging. Downy. Velvet. Black.
LV ------------------ 320 : 7 : 34 : o2
(Calculated--------- 3319 : o6 : 36 : 107)

In the Florida by Lyon cross, the plants were not on poles, and
a few stinging plants were found to have trespassed on their neigh-
bors. Any undetected cases of this would increase the apparent
proportion of stinging plants. In the Lyon by Florida cross, there
were a few cases where intermediate pods were hard to distinguish
from stinging, and a few cases where long black and Velvet were
nearly similar; otherwise the segregation was sharp. The results
of field inspection have, however, been checked by microscopical
examination of the pubescence,
From the figures for the second generations (together with the
results in the third generation), it seems certain that the segregation

Florida Agricultural Experiment Station

is in the proportion of 9:3 : :3. This agrees with a working hy-
pothesis of the inheritance of two genetic differences (factors);
one factor, B, from the Lyon bean, and one factor, C, from the
Velvet bean; which two factors are necessary for the appearance
of stinging bristles. Plants with B and not C are downy like the
Lyon; while plants with C and not B have long black tomentum on
their pods like the Velvet bean. The segregation in the third
generation shows that a third factor D, derived from the Lyon bean,
may be regarded as also present. In the presence of this factor D,
which is quite inhibited by B, black tomentum occurs all over the
plant. Factors C and D show repulsion. Hence the segregation is

Stinging. Downy. Velvet. Black Black Recessive downy.
(Long).- (Short).
9 : 3 : : 2 : I : (rare)

In the Lyon by Velvet cross, 563 plants were observed, and
though no recessive downy plants were noted, this may have been
because the calyx was not examined in every case. With no re-
pulsion, I plant in 64 should be recessive downy; with repulsion
(for example 1:7), only I in 1024. The ratio of long black to
smooth black for the second generation could not be determined, be-
cause so few black plants set pods. Among those that set pods,
there were many more (about three times as many) of the long
black; but the results of F3 and F4 showed that the smooth black
were usually more abnormal than the long black, and in most cases
set few or no pods.
Third generation from stinging parents.-The seeds from sec-
ond-generation stinging parents were planted in the elimination
field (see Florida Report for 1912). Thirty-six stinging families
were grown in competition with sorghum. The majority of the
progeny were, of course, stinging in each case. Black plants were
observed in several families, but these appear to have set no uods.
Only 16 families had 15 or more survivors each. Out of these
(I) 3 were apparently all stinging;
(2) 9 were stinging and downy;
(3) 3 were stinging and velvet;
(4) I was stinging, downy, and velvet.

Annual Report, 1914

On the hypothesis, the calculated numbers are:
(I) 2 constant stinging;
(2) 3 to 4 stinging and downy;
(3) 3 to 4 stinging.and velvet (or long black);
(4) 7 stinging, downy, and velvet (or black).
The elimination of the black plants would cause some of class
3 to appear as class I; and, together with the small size of the
families, would cause most of class 4 to appear as class 2. Hence
what has been observed of the segregation in stinging families
does not disagree with the hypothesis.
Third generation from downy parents.-Certain families from
downy parents were observed when young in the elimination field.
Including these, and adding the families from downy parents in
both crosses, we have 22 families, of which 6 gave no black plants.
If all the parents of the 22 families had the factor D, single or
double, as would probably happen on the hypothesis of repulsion,
then we might expect 7 families to be homozygous for B. If one-
quarter of the parents had no D (as would happen if there were no
repulsion), then I of the 22 families should throw no black plants.
If both D and B were single (,teterozygous) in any family, then the
ratio 13 downy to 3 black should appear (counting recessive downy
as downy). This probably occurred in at least one family. But
if there were no repulsion, it should have occurred in two-thirds
of the families which produced any black plants. In the 14 families
raised on poles, which threw black plants, the totals however were
311 downy to 118 smooth black. For the ratio of 3:1, the calcu-
lated numbers are 322:107. Thus these families show no signs of
the ratio 13:3. Thus the segregation from downy parents in the
third generation agrees with the hypothesis of repulsion, and seems
perhaps to point to a higher ratio than 1:7.
Third generation from velvet parents.-In the second genera-
tion of the Velvet-Lyon cross a few velvet plants had stiffer tomen-
tum than usual, and two of these, in the elimination field yielded
velvet and recessive 'dovny progeny. A' few other second-genera-
tion velvet plants with the ordinary soft tomentum were apparently
constant velvet, though the numbers of their progeny were too
small to be sure. In the reciprocal cross, a random sample of 4
families was grown iri the third generation. The results were:
Velvet. Recessive Downy.
LV-8o------------ 37 :
LV-3IO--------------- 32 :
*LV-475---- ------------ 4
LV-392---------_------ 9 : 5

Florida Agricultural Experiment Station

On the hypothesis of repulsion (for example 1:7), one family
out of 4 or 5 should throw recessive downy; with no repulsion, two
families out of every 3. Thus the third generation from velvet
parents agrees with the hypothesis of repulsion.
Third generation from long black parents.-The three long
black plants whose progenies were grown in this generation were
selected for maximum crop, and were different in this respect from
the other second-generation long black plants. They were thus
not a random sample. Two of them had pod tomentum very like
that of the Florida Velvet bean. Both of these threw velvet plants.
in the third generation, showing that they were heterozygous for
D only.
Long Black. Velvet.
VL-297 ------------------- : 6
LV-486--------------- 29 :

With repulsion (1:7), I out of every 9 long black plants should
throw velvet only; with no repulsion, two out of every nine. The
other second-generation long black plant had soft black tomentum
on its pods. It gave in the third generation:

Long Black. Smooth Black.
VL-437--------------- 35 :15

The 15 recessive smooth black plants showed greater floral and
pod abnormalities than the 35 plants with long tomentum.
On the hypothesis of repulsion, the majority of long black
plants in the second generation should be heterozygous for both
C and D, and these should segregate in the third generation in
small families, into nearly 2 long black to I velvet to I smooth
black. This has not been observed in the only three families which
were grown. But with no repulsion, four out of every 9 long black
second-generation plants should also be heterozygous for C and D.
Hence the results seen in the third generation of the long black
plants do not disagree with the hypothesis of repulsion.
Third generation from smooth black parents.-So few of these
second-generation plants produced a crop that it was difficult to
get enough seed. (The same was the case with the smooth black
plants derived in the third generation from downy parents.) These
plants were grown only to the seedling stage.
Black shoots. White shoots.
LV-436------------------- 49 17
LV-573------------------ 4
LV-584---------------- 7 : o

Annual Report, 1914

On the hypothesis, these plants with white shoots should be re-
cessive downy. Their pods were not seen. These three parents
are not a random sample of the second generation. As with the
long black plants, it appears as if the plants heterozygous for D
usually yield the best crops. With repulsion (1 :7), there should be
I such plant out of every 4 or 5; without repulsion, 2 out of every
3. The results of the second and third generations of smooth black
plants do not, I think, disagree with the hypothesis of repulsion be-
tween the genetic differences C and D.
Fourth and fifth generations, downy famnilies.-From the downy
plants of the third-generation family of VL-515, 7 families were
grown in the fourth generation. Six of these segregated into
downy and smooth black, giving the totals 157 downy to 57 smooth
black; the calculated numbers for the ratio 3:1 being 160.5:53.5,
and the expectation being 2 constant families to 5 segregating.
The constant fourth-generation family had 51 downy plants, and
its progeny were constant downy in many thousands of individuals
in the fifth and sixth generations. One of the fourth-generation
black plants gave only 45 black plants. Hence it seems certain that
the segregation from VL-515 is due to one factor B, the positive
homozygote being usually indistinguishable from the heterozygote.
This segregation is the most marked in the whole of this cross.
The absence of the factor B affects every part of the plant. Of the
white plants 208 were examined in the fourth generation; and of
the black plants 57; all descendants of VL-515. The following dif-
ferences were obvious to inspection, without microscopical study.

I. Stiff whitish hairs on shoots; fine
white appressed hairs, %mm. long, on
the brownish pods.
2. Vigorous growth; all vines stout.

3. Undulate leaf-blades with whitish
4. Long drooping racemes, with 30
to 60 flowers.

5. Flowers opening well; standard
rising, and with the calyx becoming
6. Style growing long, so that stig-
ma reaches pollen at tip of closed keel.
7. Flower opening rarely, and after
fertilization, by the springing of the

I. Short black flaccid hairs on
shoots and leaves; fine black tomen-
tum on the smooth, coal-black pods.
2. Growth somewhat checked; late
vines thin.
3. Smooth leaves, with weak blades
becoming convex.
4. First racemes aborting early; old-
er racemes short, often upright, some-
times reduced to 2 flowers.
5. Calyx splitting, or constricting
standard which remains appressed,
and calyx does not become gibbous.
6. Style usually short, so that stig-
ma does not reach pollen.
7. Flowers usually open at the tip of
the keel.


Florida Ai-"Il:.'.'r! Experiment Station
I lt ,r' 7

8. Many ripe pods to each raceme.

9. Pods with 5 or 6 seeds.

10. Seeds usually uniform and of
medium size (one plant was an excep-
tion to this).

II. Leaves all falling in autumn, as
the pods ripen.

8. Usually only one or two or no
ripe pods to each raceme.
9. Usually only I or 2 seeds to the
io. Pods and seeds larger and more
variable. (Probably a physiological
consequence of few pods on a large
II. Leaves persisting till killed by
frost. (A few plants set enough pods
to produce a slight leaf-fall.)

(Besides the exceptions already noted, it was observed that in
a few of the white plants the calyx constricted the standard more
than was normal. The last four of these differences are doubtless
in part the consequences of lack of pollination.) This is an unus-
ually large list of differences to be caused by the absence of one
genetic factor. The word "unit-character" could not, I think, be
used here; nor could a letter be chosen for the factor B which would
correctly symbolize the effect its presence produces.
Foitrth and fifth generations, velvet families.-Only one family
was grown on a large enough scale in the fourth generation.

Velvet .
VL-48o-6----------- 20

Recessive Downy.

One of'these recessive dowriy plants was tested in the fifth
generation, and gave a constant family. Three families of the
velvet plants were'grown in the fifth generation, and all threw re-
cessive downy. It is probable that this segregation is in the ratio
3:I. The following are all the obvious differences.

I. Unripe pods with black velvety
S2. Dry pods with brownish-black

I. Unripe pods appearing green, with
grayish down.
2. Dry pods with yellowish stiff ap-
pressed hairs.

Fourth and fifth generations, long black families.-Several long
black third-generation plants of VL-297 were propagated; one gave
constant long black; the others threw long black and velvet, probably
in the ratio of 3:1. All fourth-generation velvet plants had con-
stant velvet offspring when grown on a large scale. The following
are thechief differences observed in this particular line.


Annual Report, 1914

I. Shoots covered with blackish tom- I. Shoots covered with whitish
entum. Variable in the heterozygotes. pubescence.
2. Flowers often slightly abnormal, 2. Flowers and racemes normal.
sometimes dropping as buds.
3. Later in setting pods. 3. Earlier in setting pods.

OTHER CROSSES.-In the Florida by Yokohama cross (the Yo-
kohama has coarse down) the first generation had stinging bristles
on the pods (I plants). In the second generation, stinging, downy,
velvet, and black plants were present. The downy plants had coarse
or very coarse down, and there were many intermediates which were
not easy to distinguish from the stinging. The results of inspection
in the field are as follows:

Stinging Downy, coarse Velvet Black (White plants,
and intermediate no pods)
231 72 : 25 : 75 (4)
Calculated-.- 227 : 76 : 25 : 76

In the Florida by China cross (the China has fine down), the io
first-generation plants had stinging bristles. The second-generation
plants could readily be classified by inspection. Most of the downy
pods were fine downy, as in the Florida-and Lyon cross. One re-
cessive downy plant was found, and there may possibly have been
others; as the calyx was not closely examined in every downy plant.
The following-are the totals:

Stinging Downy, fine, coarse Velvet Black (White plants,
and intermediate no pods)
313 : 88* : 28 : 95 (17)
Calculated--. 296 : 99 : -33 101

*One recessive downy.

Thus the results of inspection in the field of the second genera-
tions of these two crosses confirm the ratios obtained in the Florida
by Lyon crosses, where the pubescence of the pods was carefully
examined with a lens or with the compound microscope.
Out of the four crosses, two of the second generations show
a close agreement'with the 9:3:1 :3 ratio; the other two show an
excess of stinging plants. Taking the ratios as 9 stinging to 7 non-
stinging we have'

Florida Agricultural Experiment Station

Stinging Non-stinging White Calcu- Excess
no pods lated of stg.

Florida by Lyon ---
Lyon by Florida ---
Florida by Yokohama
Florida by China ---



In this calculation the white plants which set no pods are omit-
ted, though the black plants which set no pods are included. This
should usually lower the observed proportion of stinging pods below
the true value, if there is no difference in earliness (or viability)
between stinging, downy and velvet. Notwithstanding this, in all
four cases there is an excess of stinging pods. There is some reason
to think that plants with stinging pods average on the whole slight-
ly earlier than those with downy or velvet pods. If this were so,
in the late white plants which set no pods we should expect a larger
proportion of velvet and downy than of stinging.
In the third generation of the Florida by Yokohama cross, a
family was grown from a fairly fruitful second-generation smooth
black plant.
Smooth Black. Recessive Downy.
VY-259--------------- 14 : 9

The chief distinctions in this family were:

I. All the pubescence on shoots and
leaves was black tomentum.
2. Short black tomentum on calyx.

3. Young pods black, with fine to-
4. Ripe pods black and nearly glab-

I. Whitish stiff hairs on shoots and
2. Whitish stiff hairs on calyx, with
a patch of long black tomentum on
3. Young pods green, with whitish
4. Ripe pods covered with stiff ap-
pressed yellowish hairs.

These recessive downy pods resemble those found in the pro-
genies of certain second-generation Velvet plants of the Florida and
Lyon crosses, such as VL-48o.


If when two quite fertile plants belonging to different conven-
tional species are crossed, the first-generation hybrids show partial
sterility, it is of economic importance to know how this partial steri-


Annual Report, 1914

lity is inherited in subsequent generations, and especially in what
way fertile plants may arise from a partial sterile parent.
C. F. Gaertner in an account of his unrivaled series of hybri-
dization experiments published in 1844, noted that first-generation
hybrid plants arising from species crosses, when partially fertile,
had a large amount of shrivelled pollen-grains, and also ovules
which did not produce embryos, though their exterior appeared
normal. In the second generation the fertility varied, but usually
decreased. It is probable, however, that Gaertner did not grow
enough plants of any second filial generation to see the inheritance
of partial sterility, since such ratios as those found by Mendel in
the second generation of varietal crosses escaped him. Subsequent
work has added to our own knowledge of the inheritance of partial
sterility the fact that quite fertile plants may arise in the progeny
of partially sterile parents. Microscopical studies (especially those
of Tischler) have shown that partial sterility is usually due to the
loss of cytoplasm, etc., from some of the pollen grains, and to the
formation of some ovules without embryo-sacs. The coat of the
pollen-grain may, I think, be regarded as a maternal structure; that
is, as predetermined in the pollen-mother-cell. The nucellus and
integuments of the ovule are maternal structures. Hence, in botani-
cal language, this partial sterility is due to abortion of some of
the gametophytes. Now Mendelian work is usually carried on with
regard to the sporophyte generation alone. As soon as I discovered
that I was working with a partially sterile cross, I desired to in-
vestigate whether the partial sterility might not be due to Mendelian
segregation affecting the gametophyte haploidd) generation. I
therefore commenced a numerical examination of (a) the pollen-
grains, and (b) the ovules and seeds of the parent plants, and of
the progenies of their crosses for several generations.
Pollen.-The pollen-grains of the Stizolobiums, like those of
most other fertile plants which I have examined, may be more or
less aborted by adverse circumstances. In the fall of the year, in
central Florida, a cool spell may occur, and the temperature fall
near 40 degrees F. for a few days. This may be succeeded by
some weeks at about 70 degrees F. Buds formed during a cool
spell were cut into sections, and found to have all their pollen-grains
empty. These buds would probably never have opened. Similarly,
flowers which opened soon after a cool spell had sometimes a large
number (up to one fourth) of empty pollen-grains. The flowers
of the Yokohama (and to a less degree of the China) beans, are
subject to some disease which blackens the anthers. (No fungi


Florida Agricultural Experiment Station

or bacteria have yet been found in them, however.) In these
flowers the pollen finally deliquesces to a black mass. If however,
we take flowers of the Florida, Lyon, Yokohama, or China beans
from healthy branches of healthy plants in warm weather, we find
almost all the pollen-grains full. Occasionally an empty grain is
met with in any flower; but the number of these is usually less than
I per cent. In healthy flowers from these four plants, each field of
the microscope shows several hundred good grains, and search is
required to find one or two empty ones. In 95 per cent alcohol
the full grains swell, becoming granular, and can be instantly dis-
tinguished from the small collapsed transparent empty ones. (This
is not the case in some other plants, such as the orange, where a
sharp contrast between full and empty grains can only be had after
careful staining with iron-haematoxylin, etc.)
The first-generation hybrid plants from crosses between the
Lyon and Florida, and between the Florida and Yokohama or
China, all showed in healthy flowers on healthy plants a large
amount, approximately one half, of empty grains. No flower was
found which had a greater amount of full grains, though more
than one hundred were examined at different periods. The most
accurate counts were made of the first generation hybrid plants of
the Florida Velvet by China cross. Counts of the pollen from
healthy flowers in 95 per cent alcohol gave 3917 quite full to 3388
empty and collapsed grains. This is 46 per cent of empty grains.
But this result has two errors. First; if the pollen is made trans-
parent by mounting in strong chloral hydrate solution, some empty
flattened grains may be seen clinging beneath the full ones. Second;
when spread in dilute alcohol under a coverglass, all the full grains
can be seen and counted; but some of the empty ones occur in heaps
which cannot be counted. Since the method employed was to take
random fields of the microscope, it is evident that if fields are omit-
ted which contain heaps of empty grains the resulting percentage
of empty grains is thereby lower than it should be. To obviate
this, dry pollen was spread thinly with the finger on an albumin-
coated slide, and fixed and stained. Counts of consecutive fields
gave ioi6 full to 1097 empty grains, or 52 per cent of empty grains.
During the staining (which was done under the coverglass), a few
grains were detached, and an examination showed that most of
these were full grains. Hence 52 per cent is too high. The true
number of empty grains is then between 46 and 52 per cent.
These first-generation hybrid plants had nothing in their ap-
pearance to indicate that the pollen of all their flowers was half-


Annual Report, 1914


FIG. 7.-Plant of the first generation of the Florida by China cross
beginning to flower at the end of August. Scale in feet.


Florida Agricultural Experiment Station

aborted. They were at least as vigorous as either of their parents
(see Fig. 7). Their half-aborted pollen seemed just as serviceable
for fertilization as pollen all whose grains were good; for they set
as many pods to the bunch as did the Florida Velvet bean. Thus,
in 1912, 38 Florida Velvet had an average of 30 flowers each on
their largest racemes. The eleven first-generation hybrids of the
Florida by Yokohama cross had an average of 33 flowers on their
largest racemes. The average number of pods on the Florida
Velvet (on the largest raceme of each plant) was 14.1 and that of
the hybrids was 14.3.
The pollen of the first-generation plants of Velvet by Yoko-
hama resembled that of the first-generation plants of Velvet by
China, as did also that of the first-generation plants of Lyon by
In the second filial generations there were distinct differences
in the amount of pollen-grains (apart from abortion or non-abor-
tion) in the anthers of different plants. Many of the black plants
especially had but little pollen in some or all of their usually few
flowers. However the majority of the white plants had as much
pollen as their grandparents. Some of them had all the grains
full in every flower examined. Others had about one-half of the
grains in all empty like the first-generation plants. By the repeated
examination of flowers from the black plants with aborted pollen
it was established that there was a slight chance of error by reckon-
ing some black plants which had normally good pollen as half-
aborted. The black plants in question had only a few flowers, and
these flowers were abnormal. Hence the recorded proportion of
black plants with half-aborted pollen is perhaps slightly too high.
Otherwise the segregation was so marked that one glance in the
microscope at the pollen spread in 95 per cent alcohol would usually
determine at once whether it was normal or half-aborted. Thus
the grains were only counted in doubtful cases.
The second generation of the Florida by China cross showed
among the white plants 208 with full pollen-grains, and 209 with
half-aborted pollen; and among the black plants, 14 with normal,
and 21 with apparently half-aborted pollen.
The second generation of the Velvet by Yokohama cross showed
among the white plants 157 with normal, and 164 with half-aborted
pollen-grains; and among the black plants, 23 with normal and 31
with apparently half-aborted pollen-grains.
A few of the plants examined had flowers with three-quarters
or more of the pollen aborted, and some of the plants reckoned as

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