3 tt F
1 1 it Oj
University of Florida
Report for the Fiscal Year
Ending June 30,
E. 0. PAINTER PRINTING CO.
LETTER OF TRANSMITTAL TO GOVERNOR OF FLORIDA ....................... vii
BOARD OF CONTROL ..................................................... viii
EXPERIMENT STATION STAFF .............. ........................... viii
LETTER OF TRANSMITTAL TO CHAIRMAN OF BOARD OF CONTROL ............. ix
Lines of W ork ..................................................... ix
Bulletins ............................................................ xiii
REPORT OF AUDITOR..................................................... xiv
REPORT OF ANIMAL INDUSTRIALIST ...................................... xiv
Dairy Herd ..................................................... xiv
Beef Herd ....................................................... xv
H ogs ....................... .... .......... ..................... xv
M ilk Record ..................................................... xv
Pig-Feeding Experiments ........................................ xvi
Cattle-Breeding ................................................. xix
Distribution of Seed ............................................. xix
Cowpeas ........................................................ xx
Soy Beans ...................................................... xxi
Yokohama Bean ................................................ xxi
Japanese Cane .................................................. xxi
Lyon Bean ...................................................... xxiv
Kudzu Vine ..................................................... xxiv
Velvet Beans .................................................... xxiv
Corn ........................................................... xxv
Guinea Grass ................................................... xxv
Para Grass ..................................................... xxvi
REPORT OF CHEMIST .................................................. xxvii
Citrus Experiments .............................................. xxvii
Soil Tank Investigations......................................... xxxn
O range Soils ................................... ................ xxxvii
New Equipment ................................................ xxxix
REPORT OF ENTOMOLOGIST .............................................. xl
Fungus Diseases of Whitefly ........................................ xl
Soap and Spraying Mixtures .................................... xlix
W eight of W hitefly Pupae ..................................... Iv
The W oolly W hitefly ............................................. vi
Migration of Whitefly............................................ Ivii
Scale-Insects .................................................... Ivii
REPORT OF PLANT PATHOLOGIST ......................................... lviii
Stem -End Rot................ ................................... Iviii
Black Rot ........................... ............................. Ix
'>Blue Mold Rot.................................................... xi
Diplodia Rot ...................................................... Ixi
Diplodia Natalensis as a Gum-Inducing and Fruit-Rotting Fungus.. Ixi
Scab ................................ ........................... Ixv
W ithertip ........................................................ Tkvi
Peach Diseases...................... ......................... Ixvi
Brown Fungus of W hitefly................ ........ ............. lxvi
REPORT OF PLANT PHYSIOLOGIST........................................ Ixviii
Problems in Citrus Nutrition...................................... Ixviii
Studies in Maximum Fertilization ................................. Ilxix
Dieback in Citrus Experimental Grove ............................. Ilxxii
M elanose ......................................................... lxxiii
REPORT OF ASSISTANT BOTANIST ....................................... IXXxii
Second Generation of the Cross between Velvet and Lyon Beans.. lxxxii
Corn Crosses ............................................. ....... civ
Sugar Canes..................................... ................. civ
Mailing and Editorial.............................................. cv
REPORT OF LIBRARIAN ................................................ ..... cv
List of Periodicals ................ .... ..................... .... cvi
BuuTrn.r 103- WmHTFLY CONTRoL PAGES T-28
How the Whitefly Injures Trees...................................... S
Summary of Life History ...............................................****.**** .
Methods of Control.................. .................... ........... 6
The Fungus Diseases.......................... ...................... 6
The Red Fungus ..... .......................... ................. 7
Experiments in Spreading Fungus................................ 7
Introducing Red Fungus .......................................... To
Other Fungi ................................................... II
Pinning Leaves ..................... ................ ........... ... 12
Artificial Culture of Fungus....................................... 12
Treatment with Insecticides ........... ................ ............. 14
Experiments in Spraying... ..... .................. .-- .......... 14
Fumigation .................................. ... .................. 17
W inter Treatment .................................................... 17
Localities Just Becoming Infested............................... 18
Badly Infested Localities ....................................... 18
Spring, Summer, and Fall Spraying.................................. 19
Spring Treatment ................................................. 19
Summer Treatment .............................................. 20
Fall Treatment ................................................... 20
Spraying Solutions .................................................. 21
Three Species of Whitelly.......................................... 22
W hitefly and Freezing................................................. 22
Q uarantine ............. ............................................... 23
Food Plants ....................................................... 24
Plainwi to be Condemned ............................................. 25
\\hiit ly and Increase of Scdal ....................................... 26
Whel.to Spray for Scales........... ....... ...................... 27
BULLETIN I04-PINEAPPLE CI.TL'RE. VII. NITRATES IN THE Son.. PAGES 29-51
Introduction ......................................................... 33
Plan of the Experiment.............................................. 35
The Samples ...................................................... 37
Effects of Different Kinds of Fertilizers on the Formation of Nitrates... 41
Effects of Increased Amounts of Fertilizer on the Formation of Nitrates. 43
Effects of Moisture, Temperature, and Growth of Plants on Formation
of N itrates ....................................................... 45
Nitrates at Different Depths ........................................... 49
Summary of Pineapple Investigations................................. 50
BULLETIN 105-JAPANESE CANE FOR FORAGE. PAGES 53-68
Introduction ...................................................... 57
History ............................................................ 58
Uses ........................................................ 58
Pasture .......................................................... 59
Silage ........ ................................................... 59
D ry Forage ..................................................... 59
Soil ......... ........................................................ 6o
Saving Seed-Cane.................................................... 60
Cane for Planting ................................................... 61
Preparation of Seed-bed............................................... 62
Planting ...................... ....................................... 64
F ertilizing ............. .................................... ......... 64
Cultivation .......................................................... 66
H arvesting ............................................... : ........... 66
Japanese Cane and Velvet Beans .......................... ............ 67
Analysis ................................................. ........... 67
BULLETIN 106-SCALY BARK, OR NAIL-HEAD RUST OF CITRUS. PAGES 1-41
Cause of Scaly Bark .... ................. .............
W here Scaly Bark is present......................... ..............
How to Identify Scaly Bark ...........................................
Control of Scaly Bark .............................................
Effects of Bordeaux Mixture...........................
Distribution and History..............................................
Development of the Disease ............................................ 1
Development of Diseased Spots... s...............................
Time of Infection ..............................................
Age of Tissue infected ..... ..............................
Investigations of the Cause ........................................... .
Cladosporium herharum, var. citricolum............................
Comparison with C. herbarum..................................... I
Experiments for the Control of the Disease...................... .... a
Spraying with Bordeaux..........................................
Spraying with Carbolineum.........................................
Copper Sulphate on the Soil........................................ 1
Top-working to Immune Varieties................................
"Summary ....................... ........ ..............................
PRESS BU LLETINS
151.-Summer Pruning for Withertip.
How to Prune.
When to Prune.
Other Effects of Withertip.
152.-Bulletins and Reports on Hand.
154.-Stem-End Rot of Citrus Fruits
Suggestions as to Treatment.
Information and Specimens
155.-Plant-Bugs in Orange Groves.
Kinds of Bugs.
z56.-The Citrus Whitefly in the Fall.
Groves Treated with Fungus.
157.-Stem-End Rot of Citrus Fruits
Observations in Citrus Groves.
Symptoms of Stem-End Rot.
Uses of Green Feed.
159.-Velvet Beans for Milk Produc-
Experiments with Velvet
Prices of Feeds.
Daily Rations per Head.
Dairy Conditions in Florida.
16o.-Hog Raising in Florida.
161.-Bulletins and Reports on Hand.
162.-Whitefly Fungus in Cold Stor-
Experiments with Cold Stor-
Results of the Experiments.
Symptoms of Hog Cholera.
Need of Legislation.
164.-Pruning for Stem-End Rot of
How to Prune.
When to Prune.
Symptoms of Stem-End Rot.
165.-Treatment of Melanose.
Cause of Melanose.
Symptoms of Melanose
i66.-Velvet Bean Seed.
How to Test Seed.
Advantages of Testing.
167.-Japanese Cane-Fertilizer Expe-
Complete Fertilizers and
168.-Improving Acid Soils.
Causes of Acidity.
Crops Benefited by Lime.
Preparation of Soil.
Yields of Hay.
Time to Plant.
How to Plant.
171.-Preparing for the jiay Crop.
Cowpea, Sorghum, and Millet
Ilsr..' To REPoitr, BULLETINS. AN'D PRrSs BtilLrrzNs
lion. A. IV'. Gilchrist, Governor of Florida, Tallahassee, Fla.
SIR: I have the honor to herewith transmit the Annual Report
of the Director of the Florida Agricultural Experiment Station, for
the fiscal year ending June 30, 1911. Respectfully,
P. K. YONGE,
Chairman of the Board of Control
BOARD OF CONTROL
P. K. YONGE, Chairman, Pensacola, Fla.
T. B. KING, Arcadia, Fla.
E. L. WARTMANN, Citra, Fla.
F. P. FLEMING, JR., Jacksonville, Fla.
W. D. FINLAYSON, Old Town, Fla.
P. H. ROLFS, M.S., Director
J. M. ScoT'i, B.S., Animal Industrialist and Assistant Director
A. W. BLAIR, A.M., Chemist
E. W. BERGER, Ph.D., Entomologist
H. S. FAWCETr, M.S.. Plant Pathologist
B. F. FLOYD, A.M., Plant Physiologist
JOHN BELLING. B.Sc., Assistant Botanist, and Editor
S. E. COLLISON, M.S., Assistant Chemist
JOHN SCHNABEL, Assistant Horticulturist
0. F. BURGER, M.S., Laboratory Assistant to Plant Pathologist
U. C. LOFTIN, B.S., Laboratory Assistant to Entomologist
*MRS. E. W. BERGER, Librarian
W. VOORHEES, Librarian
**BERTHA EVEs, Secretary
JESSIE URNER, Stenographer
K. H. GRAHAM, Auditor and Bookkeeper
M. CREWS, Farm Foreman
*Resigned, June I, 191t.
**Resigned, January 15, o9ti.
Report for Fiscal Year Ending
June 30, 1911
Hon. P. K. Yonge, Chairman Board of Control
SJi: I have the honor to submit herewith my report on the
work and condition of the Florida Agricultural Experiment Sta-
tion for the fiscal year ending June 30, 1911, and I respectfully
request you to transmit the same, in accordance with the law, to
the Governor of the State of Florida. Respectfully,
P. H. ROLFS,
LINES OF WORK
During this year our work has continued along the main lines
laid down by the projects of the previous years. Some of these
projects have been slightly broadened in their scope, while others
have been somewhat narrowed. Some have been carried on until
certain subdivisions of the project have been completed. The
projects group themselves under the following heads: (i) Horti-
culture, (2) Animal Industry, (3) Agronomy, (4) Chemistry, (5)
Entomology, (6) Plant Pathology, (7) Plant Physiology, (8) Co-
HORTICULTURE.-The work in horticulture is much the same
as that of the previous year. Nothing essentially new has been
Vegetables.-The growing of many varieties of different well-
known vegetables has been continued in order to determine their
merits and adaptability under Florida conditions, especially as to
their disease resistance and tolerance to the climatic conditions of
the central part of the State. Among the vegetables of which
varieties have been grown are egg-plants, peppers, tomatoes, and
Deciduous Fruits.-New varieties of these have been planted,
but only in a small way, and mainly from foreign introductions.
No attempt has been made to grow any of the deciduous fruits
for the mere sake of an orchard. Their adaptabilities to climatic
conditions are being tested, and also the possibility of these new
varieties being more useful than those that are already known to
do fairly well.
x Florida Agricultural Experiment Station
Citrus Orchard.-This orchard has been slightly extended, there
being no special incentive to attempt to grow citrus fruits so far
north in the State, except the more hardy varieties. The testing
of hew varieties is being continued to some extent. Such varieties
as seem likely to succeed in this region are being introduced from
time to time. The larger number of citrus trees are devoted to the
study of pathology and physiology, while a smaller number are
used for technical work in chemistry.
Miscellaneous.-A considerable portion of the horticultural
grounds is set aside for miscellaneous plant introductions, most
of which are received from sub-tropical and tropical countries.
Several hundred numbers have been tested this year, including one
hundred and twenty varieties of cowpeas. Other legumes that
show some likelihood of succeeding in our latitude are also being
tested. The alfalfa plot, from seed sown four years ago, is being
continued. This. however, shows no signs of ultimate success,
owing doubtless. to our peculiar climatic conditions. Among the
grasses that h:li been introduced and are giving promise of suc-
cess are, Rhlodes Grass (Chloris Gayana), Chaetochloa aurea
(S.P.I. No. 13880 o. and Molasses grass (Melinis minutiflora).
Soudan grass (S.l'.I. No. 25017) has made a rather vigorous
growth but does not seem to be better than several other grasses
that would fill the same need and are already well acclimatized. New
plantings of Yokohama bean (Sticolobium hassjoo), Lyon bean
(Stizolobium niz'eum), and other closely related species are being
continued. In the case of Stizolobium niveum, the first introductions
are doing unusually well. One new strain which originated from
a single seed (and probably forms a pure line) seems to be earlier
in fruiting and more productive than the earlier introductions.
Should this continue to be as early and productive when planted on
a field scale, it will doubtless largely supplant the original intro-
ANIMAL INDUSTRY.-The line of work laid down in former
years has been continued. The work of hog-feeding has been
given more attention during the present year than heretofore.
A considerable amount of valuable information has been secured,
and exact data as to the possibilities of using Florida-grown feed
stuffs have been determined. Feeds and forage crops have been
tested as to their usefulness for hog-raising and stock-raising.
Thev have also been tested to ascertain the quantity that can be
produced per acre.
CHEMISTRY.-The work has been continued as outlined in the
last Annual Report. The project for determining the effects of
certain fertilizers on the soil, together with their effects on citrus
Annual Report, I911
trees, has been carried out in the proposed manner. Records of
soil temperature, air temperature, and rainfall have been kept to
supplement the analyses of the soils.
The first set of four soil tanks has been installed. The amount
of water draining off from these, which approximates to the amount
of water that would ordinarily be lost by leaching in a citrus grove,
has been determined. Chemical analyses of this water will show
what fertilizer constituents have been lost by drainage. The amount
of moisture retained by the soil in the tanks has also to be de-
termined. A record of the rainfall is kept. The amount of rainfall,
less the amount of moisture retained in the tanks and the amount
of drainage water, gives the amount of evaporation that occurs
from this area at the particular point where the tanks arc located
ENTo.Mot.oGY.-The work in entomology has been continued t,
the study of the whiteflies attacking citrus trees. Three ~picies
of whitefly are now known to occur in the State: the clear-winged
species (Aleyrodes citri), the cloudy-winged species (.Allcyrodes
nubifera). and the woolly whitefly (Alevrodcs hoi'ardii). The
work of treating the first two species by their fungus diseases has
been continued, and definite data have been secured as to the value
and practicability of using these fungi as agents for an economic
reduction of the number of whiteflies. Some work has been done
on securing contact insecticides which will prove effective in com-
bating these pests.
PLANT P'ATHOLOGy.-The work on Scaly Bark, which was
begun in 1905. has been brought to a completion, and a final bulle-
tin on the subject has been issued. It is thought that this portion
of the project is now complete so far as the investigational side
of the subject is concerned. The most active work in the citrus dis-
ease project has been done on the Stem-End Rot. This was found
to cause serious loss to matured fruit in the grove, as well as to
fruit in transit. The nature of the fungus has been worked out
more or less definitely, and experiments in the field with a view of
discovering a remedy for this serious trouble have been inaugurated.
Much work has also been done on the disease of citrus known as
Gummosis. The causative agent for this citrus malady has not
been definitely determined.
During the year, the parasitic organism responsible for the pro-
duction of the disease on peach trees known as "Gumming" was
discovered. Certain remedial measures have been suggested, and
some have been put into practice. The discovery of the cause will
aid materially in finding a practical method of combating this rather
prevalent and serious peach disease in the State.
PLANT PHYSIOLOGY.-The lines of work as heretofore carried
Florida Agricultural Experiment Station
out have been continued. Many data have been secured as to the
effects of certain chemicals and their relation to the proper function-
ing of citrus trees. In the studies of malnutrition much information
has been secured as to the exact nature of dieback. These
data have heretofore been wanting, and the lack of such has im-
peded the progress toward securing remedial treatment for this
common malady. The construction of a greenhouse, 21 feet by
42 feet in extent, has added materially to the equipment for this
work. This house has no facilities for heating, but is especially
useful in getting plants under exact control conditions so far as
rainfall, wind, and other such conditions are concerned, and to a
large extent protects the citrus trees used in the tests against freez-
ing in winter.
PLANT BREDING.-The work of plant breeding has been con-
tinued, and statistical data have been secured, especially in regard
to the second generation of the Lyon bean and the velvet bean
crosses. In this case we have segregations resulting from the cross-
ing of presumably two botanical species. With the progress of
this work it is probable that some interesting factors will be dis-
covered in connection with segregation after hybridization, es-
pecially in regard tu size, yield, and earliness.
CO-OPERATIVE WORK.-A large amount of co-operative work
has been carried on with officers of the United States Department
of Agriculture. This work is being continued with the offices of
Seed and Plant Introduction and Distribution, with the Bureau of
Chemistry, and with several other offices of the Department.
Co-operative work was also carried on with the Extension Di.
vision of the University, a large amount of seed of the Lyon bean,
Yokohama bean, Brabham cowpea, and Iron cowpea being furnished
to this Division for co-operative work with farmers in various
parts of the State.
NEW BUILDING.-During the fiscal year the Experiment Station
Building was completed and turned over to the officers of the Ex-
periment Station for occupation, the Legislature having appro-
priated $4o,ooo for a building to contain the laboratories and
offices of the Experiment Station. In addition, $7,500 was allotted
for the equipment of the laboratories and offices. The building is
of brick, three stories high, io8 feet long, and 65 feet broad.
This commodious building gives ample accommodation for all
of the Experiment Station work. It also houses the Farmers' In-
stitute workers. It is especially well equipped as an Experiment
Station building, every room having been designed especially for
that particular line of work for which it is to be used.
STATION STAFF.-During the present fiscal year no changes of
importance in the personnel of the staff have occurred. Changes
Annual Report. 1911 xiii
in minor offices have occurred from time to time. These have
not affected the working of the institution. A. B. Massey re-
signed his position as laboratory assistant in Entomology on July
31, 1910; U. C. Loftin accepted the position, and began work on
December i, 1910. B. B. Ezeli resigned the position of laboratory
assistant in Plant Physiology on July 31. 1910o, and the work was
carried on for the remainder of the year by temporary assistants.
On January 1, 1911, Miss Jessie Urner accepted the position of
stenographer, and on the fifteenth of the same month, Miss Bertha
Eves resigned the position of secretary. On June 1, 1911. Mrs.
E. W. Berger resigned the position of librarian, which was accepted
by W. Voorhees on the same date.
The following press bulletins and bulletins, with the annual
report, were published during the year.
No. Title Date Author
151. Summer Pruning for Withertip... July 2, 191o ......... H. S. Fawcett
152. Bulletins and rep,,rt on hand ........July 9, 191o .........
t53. Hay ........................... Sept. o10, 19o 10....... P. H. R'.Ifs
154. Stem-end Rot of Citrus Fruits, Ill Sept. 13, 1910o ....... H. S. Fawcett
155. Plant Bugs in Orange Groves..... Sept. 24, 1910o ....... P. H. Rolfs
156. The Citrus Whitefly in the Fall.... Oct. I, 1910o ......... E. W. Berger
157. Stem-end Rot of Citrus Fruits, IV Oct. 29, 91o 0....... H. S. Fawcett
18. Feeding Hogs .................... Nov. 5, 19io........ J. M. Scott
159. Velvet Beans for Milk Production. Dec. 10o, 1910....... J. M. Scott
. Hog raising in Florida .......... Jan. 7, 1911 ......... A. P. Spencer
161. Bulletins and Reports on Hand... Jan. 7, 1911.........
162. Whitefly Fungus in Cold Storage.. Jan. 14, 1911........ E. W. Berger
:63. Hog Cholera ..................... Jan. 21, 1911 ........ A. P. Spencer
164. Pruning for Stem-end Rot of Citrus Feb. 4, 1911 ........ H. S. Fawcett
165. Treatment of Melanose .......... Feb. 1, 191i.....B. F. Floyd
166. Velvet-Bean Seed ................ Mar. 4, 1911 ....... J. M. Scott
167. Japanese Cane.-Fertilizer Experi-
ments .......................... Apr . 1911 ........ P. H. Rolfs
168. Improving Acid Soils............ May 13. 1911........ A. W. Blair
169. Sweet Potatoes.......... ...... May 27. 1911... .... C. K. McQuarrie
170. Cowpeas ................ .... June to. 1911 ........ J. M. Scott
171. Preparing for the llay Crop....... June 24. 1911....... C. K. McQuarrie
103. Whitefly Control; 28 pages....... Sept.. t19o ......... E. W. Berger
10o4. Pineapple Culture. VII. Nitrates
in the Soil: 23 pages........... Oct., 190o ......A.. .\. W. Blair and
105. Japanese Cane for Forage: 16pages Feb.. 1911 .......... J. M. Scott
io6. Scaly Bark or Nail-Head Rust of
Citrus; 41 pages................. June. 191 ......... H. S. Fawcett
ANNUAL REPORT for 1910; 96 pp.. with index to all bulletins.
Florida Agricultural Experiment Station
REPORT OF AUDITOR
P. H. Rolfs, Director
SIR: I submit the following financial report for the year ending
June 30, 1911.
Balance from last year's incidental funds........................... $ 555.85
Adams fund appropriation ....................................... 15,000.00
Hatch fund appropriation ........................................ 15,ooo.00
Proceeds from sale of farm products and fees .................... 798.23
Total ..................................................... $31,354.o8
Hatch Adams sources
Salaries ................................. $ 6,708.51 $o.o3.79 $ .......
Labor ........ ........................... 3.079.93 573.18 152.87
Publications ........................... ....... 1,279.79 ....... 26.80
Postage and stationery .................... 374-92 7.I14 21.24
Freight and express ....................... 123.54 240.30 19.99
Heat, light, water and power................... 6o. 200.99 2.40
Chemical supplies ........................ 5.25 823.92 2.75
Seeds, plants and sundry supplies............. 282.35 420.84 45.92
Fertilizers ...... . .. .................. 219.59 82.70 .......
Feeding-stuffs ... .... .. ...... ........... Io84-45 ....... 35.25
Library .......................... 410.43 56.03 9.62
Tools, implements and machinery............. 205.37 121.17 86.86
Furniture and fixtures ...................... 30.00 ....... 3.50
Scientific apparatus ........................ ....... 1,150.21 .......
Live stock ................................ 5.00 ....... ...
Traveling expenses ........................ 26o.o9 830.25 8.80
Contingent expenses .......... ............. 25.00 ....... .......
Buildings and land ....... ................ 745.67 489.48 587.66
Balance ........... ... .................... ....... 350.42
$15000ooo.00 $15,000.00 $1,354.o8
Total ............... .................................. $31,354.08
K. H. GRAHAM.
REPORT OF ANIMAL INDUSTRIALIST
P. H. Rolfs, Director
SIR: I submit the following report of the Department of
Animal Industry for the year ending June 30, 1911.
The dairy herd remains the same as given in the last Report.
with the exception of the increase in calves. A number of the
cows have had calves during the year, but only three of these have
been selected to remain in the dairy herd, the others having been
sold for veal.
Annual Report, ip9z xv
Since the last report one Shorthorn bull has been sold. The
herd remains the same, consisting of four Shorthorn cows and
The herd of swine consists of four Berkshire sows and one boar.
During July, 1910o, the four sows farrowed, and 26 pigs were
raised. These pigs were all retained, and used in the feeding ex-
periments given in this report. The four sows farrowed again
the latter part of February, and 27 pigs were raised. Of these,
seven (six sows and one boar) have been sold to farmers of the
Table I shows the age; breed; date at which the cows became
fresh; number of days they gave milk from July i. 1910, to June
MII .KINC RECORD
June 18, '10
Sept. 14, '10
June 18, '10
Jan. 2. '10
Feb. 24. '11
Aug. 31. '10
June 18. '10
March 29, '11
Feb. 10. '11
Rept. 6. '09
Aug. 19. '09
Dec. 28, '10
*a S. ~
0 *a.b tt g
s. 4..5 ^=
1^ * s "
la 5 on5 5
1 3 yrs.
2 12 "
4 3 "
5 11 "
0 10 "
8 12 "
9 3 "
10 10 "
11 11 "
13 10 "
14 3 "
July 18. '10
Florida Agricultural Experiment Station
30, 1911; amount of milk produced from July 1, 1910, till June
30, 1911; percentage of butter fat; and date when each cow dried
The best yield of milk for the year was 4683.3 pounds, by Cow
No. o10. The smallest yield was produced by Cow No. 13, namely
938.9 pounds. It will be noticed that Cow No. 13 freshened on
August 19, 1909, and dried up December 12, 1910o, which accounts
for the small yield of milk during the year. Cow No. 8 is a native
Florida cow. Cow. No. 14 is a calf from Cow No. 8 and a pure-
bred Shorthorn bull. This cow was 28 months old when she fresh-
ened. During the 184 days she produced 1876.3 pounds of milk.
This is not a big yield; but, when we take her ancestry into consider-
ation, it makes a fairly good showing.
The object of these experiments was to test the value of some
of our home-grown feeds.
FIRST EXPERIMENT.-The feeds used were velvet beans in the
pod. Japanese cane. and sweet potatoes. These were all fed just
:i- they came from the field, except the Japanese cane. which was
cut into short pieces with a hatchet. There were 25 pigs in all.
fivc pigs in each lot. Lot I was fed velvet beans in the pod only.
Lot II was fed equal parts by weight of velvet beans in the pod and
Japanese cane. Lot III was fed velvet beans in the pod one part,
and Japanese cane two parts by weight. Lot IV was fed Japanese
cane only. Lot V was fed velvet beans in the pod and -weet pota-
toes. equal parts by weight.
WEIGHTS AND GAINS OF PIGS IN POUNDS
Lot Lot Lot Lot Lot
I I III IV V
Weight at beginning, December 13, 1910...- 280 230 235 215 215
Weight at end. February 11, 1911 (60 days) 255 234.3 227.3 154 227.8
Total gain or loss in 00 days__ 25 4.3 -7.7--1 12.3
PoUNDs OF FEED CONSUMED
Feeds Lot Lot Lot Lot Lot
Feed I 1 III IV V
Velvet beans In pod--.---- -- 637 450 405.5 --- 474
Japanese cane-------------_ --- --- 450 804.5 304.5 -
Sweet potatoes---------- --- -- ----- .480
Annual Report, 1911
The three crops used in this feeding experiment are grown, or
can be grown, in all parts of Florida. It appears from the results
of this test that in the proportion in which they were fed. they
were not at all satisfactory in financial returns. It is the informa-
tion obtained which is of value to the live stock interests of the
The gain made by Lot I is the largest made by any of these
pigs, but it is very small. It is not what one would expect from
pigs when fed liberally. It appears from this experiment that velvet
beans in the pod do not form a good feed for pork production.
The results of feeding Japanese cane alone to pigs of about
forty pounds in weight shows clearly that it is not a good feed for
growing pigs. It also appears that a combination of equal parts
of velvet beans in the pod and Japanese cane did not produce satis-
By examining Table II it will be seen that all the lots of pigs
weighed nearly the same at the beginning uf the experiment; but
that at the end of the experiment. sixty days later, there was quite
a difference in the weights of the different lots. Lot I, fed velvet
beans in the pod only. made a gain of 5.' pounds. Lot II, fed equal
parts of velvet beans in the pod and Japanese cane, gained only 4.3
pounds. Lot III. fed velvet beans. in the pod (one part). and Japain-
ese cane (two parts), made a loss of 7.7 pounds. Lot IV. fed
Japanese cane only, made a loss of 61 pounds.
SECOND EXPERIMENT.-IIn this experiment the following feeds
were used: corn, cull velvet beans, shorts, and green sorghum.
The cull velvet beans were the refuse taken from the seed velvet
beans. The beans as they came from the field were put through
the huller and were afterwards screened through a screen of three-
eighths inch mesh. All beans that went through the screen were
considered as culls. These consisted of immature, shriveled and
The twenty pigs were divided into four lots of five pigs each.
Lot I was fed shelled corn only. Lot II was fed shelled corn and
cull velvet beans, equal parts by weight. Lot ITT was fed shelled
corn. cull velvet beans, and shorts, equal parts by weight. Lot IV
was fed shelled corn and cull velvet beans (equal parts by weight).
and all the green sorghum the pigs would eat.
The corn, cull velvet beans, and shorts were soaked before feed-
ing. The evening feed was weighed out in the morning and soaked
until evening, and vice versa. Feeding green sorghum was begun
on May 9. 1911. The experiment began March 21. 1911. and closed
June 16. 1911, lasting 90 days.
The following table gives the results in detail.
Florida Agricultural Experiment Station
\\Vu.l IS AND GAINS OF PIGS IN POUNDS
I Lot I Lot II Lot III Lot IV
Weight of pigs at beginning ------------ 291.0 260.0 274.0 265.6
Weight at end 100 days -------------------- 406.6 345.0 390.0 373.8
Giin per lot (90 days) --------------------- 115.6 78.4 110.0 108.0
Dally gain per head ...------------------------ 0.26, 0.17 0.26' 0.24
Dnily gain per 1000 pounds live weight -------..... 4.4 3.3 4.7 4.5
Cost per pound of gain------------------- $ 0.08 0.10 0.0Oi 0.08
v'ost per 100 lbs. ,if gain ------------------- $ 8.10 0.00 8.98 7.99
Pounds of feed to mnke 100 pounds gain .... 546.2 797.2 641.7 1118.1*
*552 pounds of this was green sorghum.
POl'NDS OF FEED CONSUMED)
Lot I Lot II Lot III Lot IV
Corn ----------- --------------------- 631.4 312.5 248.1 327.)
Velvet beans ----------------------------- 312.5 248.1 327.8
Shorts .---------- ----- ------- -- .. 248.1 -.
Green sorghum ...... ----------- --- 552
The results in the second feeding experiment were more satis-
factory than in the first experiment. The weights of the different
14I ns of pigs were nearly the same at the beginning. The average
daily gain per head was about the same for all pigs except those in
I.ot II. The cost per pound of gain varied from 7.96 cents to 9.96
cents. The cheapest gain was made with Lot IV, on corn, cull
velvet beans, and green sorghum. With this feed it cost $7.96 to
make one hundred pounds of. pork. With Lot I, which was fed
shelled corn only, it cost $8.19 to make one hundred pounds of
gain. With Lot II, on shelled corn and cull velvet beans, it cost
$9.96 to make one hundred pounds of gain. Lot III with corn, cull
velvet beans and shorts, required $8.98 to make one hundred pounds
THIRD EXPERTMENT.-This experiment began June I, 1911.
The number of pigs was 17; and their age, three months. The
total weight of the pigs at the beginning of the experiment was
590 pounds, with an average weight of 34.7 pounds. The feeds
were shelled corn and shorts (equal parts by weight), about forty
pounds of milk a day, and all the green sorghum the pigs would
cat (14 to 16 pounds a day).
The objects of the experiment were to ascertain the cost of pro-
ducing a pound of pork with young pigs, and the length of time
from weaning until the pigs were ready for market. The amount
of feed required to make ioo pounds of gain during the thirty
days was: corn, 148.5; shorts, 153.4; milk. 239.3; and green
sorghum, 83.9 pounds.
Annual Report, 191i
The following tables show the results of the feeding test.
WEIGHTS An GAINs OF PIGS
Weight at beginning of experiment ---------------------...... ---590
Weight at end of 30 days-..-- .- .... .. ..8. S
Total gain in 30 days--...- ...-----------------------.. 191
Average daily gain per head--- - -...--...-...._. 0.96
Average daily 'nlin per 1000 pounds live weight- ------- 27.4
Corn -- ----.. .. 729 pounds
Shorts ------ ---------------- 753 pounds
Milk -- ---- 1175 pounds
Sorghuml. green ---- -- 412 pounds
The work of improving the native Florida cattle, mentioned
in my previous Reports, is still under observation.
The following table shows the weight per head per month, be-
ginning with July T. 1910o.
WEIGHTS OF CATTLE IN POUNDS
V s s
Grade Shorthorn (Redi--- 60590159215651559i540!5251537 552507602 00
Grade Shorthorn (Brindled -- 32 545545i.5547!5301525,5551577 000610600
Grade Hereford (Steer ----- 48( 505500o505|4951490t460'462:482 507 535'540
Grade Hereford (Heifer i - 51 1580 5251 545 535 5155542560 5806.025 630
Native (Spotted)------.------- 55250 572'565 50856053015571582610 650 640
Native (Red) -----.-------...- ...... 522530 54055057550 535542576 610632 630
DISTRIBUTION OF SEED
During the year a large amount of seed was supplied to the
Extension Division for distribution among the farmers of the
State. The seed included Velvet beans. Lyon beans, Yokohama
beans. Iron cowpeas. and Brabham cowpeas. In all. about 5o
bushels of seed was sent out. and to nearly all parts of the State.
Florida Agricultural Experiment Station
The work with cowpeas was not only a variety test, but also a
test of disease resistance and of the best methods of planting. All
things considered, the Brabham and Iron were found to be superior
to the other varieties. It will be seen, by referring to Table IX,
that in nearly every instance these two varieties gave a better yield
The Iron and Brabham were the only two varieties that were
found to be resistant to root-knot. This is an important fact in
Florida where root-knot is prevalent on many of our farm crops.
Fig. i.-Brabham cowpvas. YVidd of hay-two tons per acre.
If these two varieties continue to be as resistant to root-knot as
they have been in the past three years it will enable Florida farmers
to grow valuable crops of hay after the spring and summer vege-
table crops have been harvested. In the past, farmers would not
grow cowpeas. because by so doing the soil would be infested with
the root-knot worm. If such infested cowpeas are followed by a
vegetable crop. it is almost sure to fail.
The following table gives the comparison of the methods of
planting. This shows some advantage in favor of planting in
rows and cultivating. If. however, the cowpea hay be grown for
the feeding of horses and mules, it would be better to sow the seed
Annual Report, 1911
broadcast. This method will require 50 per cent. more seed. but it
will give a better quality of hay for the feeding of these animals.
This is because a combination of cowpea and crabgrass hay is
better for horses and mules than cowpea hav alone. If the cow-
peas be sown broadcast it will give the crabgrass an opportunity
to come up.
YIFLDS OF COWPEAS
Pounds of Hay Per Acre
Name and Number of Variety I Sown broadcast Planted in rows
_______ I_-and cultivated
Brabham ihome-grown seed --- ------ 2350 2520
New Era (27547)--------------------- 1530 1050
Red Ripper (2754) ------------------- 1600 1312
Unknown 27545 -- ------------ --- 1050 2056
Iron (27544 ------------------------- 1700 2012
Whippoorwill (27543 ------------------ 1250 1837
Groit 26497 ------------------------ 1050 962
Peerless (26495) ---------------------- 1650 2231
Hrabbam (26407) --------------------- 1750 1837
Out of some eighty varieties tested this year, Mammoth, Black,
Nielson. Yellow, Canton, and Edwards, proved worthy of further
trial. These will be grown on larger areas in the coming year to
test the yield of both hay and seed.
The Yokohama bean, from the results obtained this year, ma-
tures and ripens its seed much earlier than the Velvet or Lyon bean.
The seed was planted May 6. 1910o, and the crop was mature and
ready to harvest in the latter part of August. This bean requires a
growing season of loo to io20 days. At the present time we cannot
say much about its yield as compared with the Velvet and Lyon.
It does not make as rank a growth of vine. If it proves to produce
as large a crop of seed as the Velvet and Lyon it will be of consider-
able value as a forage crop for the northern and western counties.
where the Velvet bean will not mature. Because it does not pro-
duce such a rank growth, it will be of value as a cover crop in the
CULTIVATION TEST.-An experiment was started during the
spring of 1910o for the purpose of getting some information as to
xxii Florida Agricultural Experiment Station
the-best depth of cultivation for this valuable crop. The cane in
the field used was one year old. The field was divided into four
plots of equal size.
CuLTIVATIro TEST OF JAPANESE CANE
Plot Depth of cultivation Yield of green
Plot Depth material per acre
1 Cultivated 2 Inches deep -------------------- 16.6 tons
2 Cultivated 4 inches deep -------------------------- 10.5 tons
3 Cultivated 6 Inches deep----------------------- --- 18.0 tons
4 Cultivated 6 Inches deep at first and 2 inchlts deep
afterwards ....---------------------------- 17.0 tons
Fertilizer was applied as follows:
Dried blood .----------------------... 75 pounds per acre
Acid phosphate---- .... --------- 150 pounds per acre
Muriate of potash -------- ..-------- 5 pounds per acre
Total --------------- --------- 281 pounds per acre
All plots received the same treatment, except the cultivation to
The results .,f this year's work would seem to indicate that the
depth of cultivation had but a slight effect upon the yield per acre.
It has always been presumed that deep preparation and shallow
cultivation during the growth of this crop would give the best re-
sults. However, the Japanese cane is somewhat different from
most forage crops in that it continues to grow until frost, though
cultivation ceases about July i. Under such conditions root mu-
tilation by deep cultivation is not so likely to injure the crop.
FERTILIZER TEST.-The fertilizer test with Japanese cane. given
in last year's Report, was continued in the present year. The fol-
lowing table shows the fertilizers applied, and the yield of green
forage per acre.
JAPANF-SE CANE FERTILIZER TFST, 1910
Plot I Plot Plot Plot Plot iPlot Plot Plot
1 2 8 4 5 6 7 1 8
Dried blood-----....------ 112 ---- 112--- 112! --- 112 112
Sulphate of ammonia -- ---.........----- ---.. --... ---72 -- 72, _---
Muriate of potash------ 84 84 ----- 84 84 ----- ----- .-
Sulphate of potash----- ----- --- .... I 84 ..84 84
Acid phosphate---- ------- -224 224 224 224 224 224
Total fert. per acre----- 196 308 386 80 4201 380 420 420
Yield tons per acre ... 14.61 12.4 10.0 14.4 11.8 10.7 14.11 16.0
Sucrose --------------- 11.0 10.85 10.50 11.0 11.20 11.10 10.95 10.90
Brix .........--------- 15.85 15.40 15.30 15.40 15.60 15.60 15.501 15.50
No limestone was applied this year.
Annual Report, 1911
It is sometimes asked, "What percentage of the crop of Japan-
ese cane is leaves?" This perhaps is not of much importance, ex-
cept where the crop is used for making syrup, and the leaves are
saved and used as forage. In 1909 and 1910, eight weighing were
made from each year's crop. Twenty stalks were weighed from
each plot. The canes were cut, weighed, then stripped as for grind-
ing, and weighed again. The difference of the weight of the whole
canes and stripped canes was taken as the weight of the strippings.
On the average of the two years the leaves formed 25.4 per cent.
of the whole crop, being slightly less in 1909, and slightly more in
The calculated yield of syrup per acre from the 1909 crop of
Japanese cane varied from 194 to 334 gallons. At 50 cents per
gallon for the syrup this would have a gross value per acre of $87
to $166. The calculated yield of syrup per acre from the 1010
crop varied from 112 to r8o gallons. At 50 cents per gallon for
the syrup, this would give a gross value of $56 to $90o per acre. If
we deduct from these figures the cost of grinding and putting the
syrup on the market, we still have a fair profit per acre for growing.
Aside from the profit in the syrup there is a fair amount of good
hay that should be taken into account. If a field of Japanese cane
produces a yield of twenty tons per acre of green material, this
gives five tons of green leaves, which when cured will make one
and a-half to one and three-quarter tons of good hay, worth from
$r8 to $25.
CAICULATHI- VFi.LD OF SYRUP PER ACRE
JArANVSF CANE, 1909 CROP
Plot No. Sucrose Brix per acre per acre
per cent degrees pounds gallons*
1 ----------------------------- 11.85 16.7 15309 209
2 --------- ------.---.....--- 18.50 17.2 10625 207
3 ...----------------------------- 18.75 17.7 10417 200
4 ----------------------------- 13.65 17.4 12311 243
5... ----------------------------- 18.60 17.4 12466 240
--- ....----- --------------- 13.50 17.5 11477 22R
7 --------- 17.1; 119lli 194
8 ------------------------..---- 18.74 17.8 16488 333
1- -- 11.00 1.:-,5 9211 11 -
2 ----------------------------- 10.85 15.40 7451 180
3........---------------------------- 10.50 15.30 6440 112
4 --.......--------------- ------- 11.00 15.40 0299 162
5.- -------------------- 11.20 15.60 7548 184
S.--------..-------------------11.10 15.60 10169 180
..... ..... ...---------------------- 10.95 15.50 8229 145
8 --------------------------........ 10.90 15.50 9760 172
*Gallons of syrup were estimated from the Brix reading.
xxiv Florida Agricultural Experiment Station
The hand-selected Lyon-bean seed gave a yield of 11.9 bushels
of shelled seed, while the seed as it came from the huller gave
a yield of 1o.96 bushels of shelled beans.
Two cuttings of hay were made this year from the Kudzu.
The first cutting was made on June 14. On account of excessive
rain after cutting, it was not weighed, but was estimated at 1500oo
pounds per acre. The second cutting was made on September
6, and yielded 2005 pounds of cured hay per acre. The total yield
for the season was about two and three-fourths tons of cured hay
After the second cutting the vines made almost no growth.
Tlhii rather indicates that two cuttings in one season is more than
the plant will stand. It was rather slow in putting out new growth
this spring, in fact, it has not made a rank growth at all.
So far the Kudzu vine has not been promising.
The yield of velvet beans was low this year as compared with
former years. This was due largely or almost entirely to the frosts,
Fig. 2.-Velvet beans, showing first and fourth crops on the same land.
Annual Report, 1911
which occurred nearly a month earlier than usual. This not only
reduced the yield, but injured a large amount of seed for planting.
On the acre used for continuous planting, the yield was 1392 pounds
of beans in the pod, or 13.9 bushels of shelled beans. This is the
fourth consecutive crop of velvet beans grown on this acre. The
yield on an adjoining plot, which previous to this time had not
grown velvet beans, was 2176 pounds of beans in the pod, or 21.76
bushels of shelled beans, per acre. It was impossible t, see any
difference in the appearance of these two crops when growing. The
"white" velvet beans yielded 1523 pounds of beans in the pod, or
15.23 bushels of shelled beans, per acre.
Hand-selected seed gave a yield of i 1.98 bushels of shelled seed,
while the seed as it came from the huller yielded 16.1 bushels per
Nine varieties of corn were used in the variety test this year.
The following table gives the percentages of barren stalks, and the
yields per acre.
Although there are no heavy yields in the list, yet it affords
an illustration of what may be accomplished by systematic selection.
It will be noticed that the percentage of barren stalks varies from
11.7 to 63.9. The best yield was obtained from the variety with
the smallest percentage of barren stalks, a variety which the Station
has been growing for three or four years. By persistent selection
we have eliminated a large percentage of the barren stalks.
CoRN VARIETY T.ST. 1910
Percentage of Bushels of corn
Name barren stalks per acre
Evans ________ -------------- 15.6 14.35
Renfroe ------------------- 3.9 7.92
Danley ------------- ----- 26.5 10.63
Blitch ---_---------------------- 28.1 9.78
Station ._.--- - -- ---.---_------- 11.7 17.53
Mosby -------------- ------ 32.4 7.92
Rawls .- ----.. ---------- 16.4 13.64
Poorland --------------------------- 15.6 13.78
Cuban .- -- .---_------------ 17.4 9.57
The Guinea grass is not proving to be as good as it was hoped
it would be. Gainesville appears to be too far north for this grass
to succeed well. The winter frosts cause more or less injury each
xxvi Florida Ayricultural Experiment Station
The first cutting was made on September 5, 1910. One plot was
fertilized as follows:
Nitrate of sodai ....------- ----..-----.. 40 pounds
Muriate of potash ------------------------ 30 pounds
Acid phosphate--- ---------------------- 80 pounds
Total per ncrt ---------- ------- 150 pounds
This gave a yield of cured hay per acre as follows:
First cutting, September 5, 1910 ----------- 250 pounds
Second cutting, November 22, 1910 ---------- 720 pounds
Total for the two cuttings -------3370 pounds
A second plot was fertilized as follows:
Dried blood---..--..-------------- -- -------- 38.5 pounds
Murlate of potash -- --------- - --------30.0 pounds
Acid phosphate- ..----------------------- 80.0 pounds
Total pr icr. -_ -_-. --------- 148.5 pounds
This gave ,a yield of cured hay p r acre a; follows:
First cutting. September 5. 1910--... ------1801 pounds
Second cutting. N,-vember 22, 1110 -- ----- .40 pounds
Total for tihe I wo cuttings.- --.. 2:341 pounds
Two cuttings of Para grass were made this year. The plot
was fertilized as follows:
Nitrate of sod ....--------------------------- 411 pounds
Muriate of potash----------- ----------- 311 ponds
Acid phosphate --------..... 8----------------- pounds
Total per nero_ ----------------------150 pounds
This gave a yield of cured hay per acre as follows:
First cutting, September 5. 1910 --------.........--1250 pounds
Second cutting. November 22, 1910 ......---------1150 pounds
Total.for the season-------..........---....... 2400 pounds
The fertilizer for the Guinea and Para grass was applied in
two applications. The first application was made on May 27,
1910o, and the second on September 1o, 1910o.
JOHN M. SCOTT,
Annual Report, 1911
REPORT OF CHEMIST
P. H. Rolfs, Director
SIR: I submit herewith the report of the work in Chemistry
for the year ending June 30, 1911.
C(TITUS EX.I'I.IM ENT.
FERTILIZATION.-The experimental grove has been fertilized
three times during the year, on December 7, March 22, and June
.-*. the amount and formula remaining the same as last year. With
a few exceptions, the plots do not differ greatly in appearance;
though on making measurements it is found that there are decided
differences in the various plots. Some of the trees in the plot that
has received no fertilizer are beginning to indicate, by a yellowing
ot the leaves, a need of nitrogen; though otherwise thick d
appear to be suffering for want of fertilizer. The clean cuhltre plots
are slightly above the general average in appearance. The plots
that have received their phosphoric acid in the form of floats, stand
well up in the average, as is shown in Table XIV.
During July, 1910.o, Mr. Wakelin found that dieback was quite
prevalent in the grove. This no doubt interfered with the normal
growth of the trees, and some made no June growth. We were.
however, unable to find any relationship between the fertilizers
used and the presence or absence of dieback. Later, B. F. Floyd
made careful notes on the amount of dieback present, and confirmed
our observations as to the lack of relationship between the kind of
fertilizers used and the prevalence of dieback. He proposes to
make further observations from time to time.
CULTIVATION.-With the exception of the three clean culture
plots. cultivation was discontinued during the rainy period, and
was not commenced again until late in November. Late in July,
strips were mowed on each side of the rows to keep the grass
away from the trees; and about a month later the grove was mowed
and the hay removed.
The trees were banked during the winter, but at no time were
they in.danger from the cold. The banks were removed at the
time of the spring fertilizing; and early in April the grove was plow-
ed north and south, followed immediately by the Acme harrow. Har-
rowing was continued at frequent intervals during the dry weather.
RAINFALL AND TEMPERATURE RECORDS.-The total rainfall for
the year was 41.20 inches, distributed as follows:
July ---------- 8.96 -November .... 1.11 Mnarch- ----- 1.15
August ------- 7.54 December ---..... 0.( April --.---- 0,R
September .... 0.84 January ------ 0.67 Mny 5----.80
October ----....... .07 Februnry ----- 0.n' .Inu1e1 .-..-.60
Florida Agricsdtural Experiment Station
The records from the air and soil thermographs located in the
grove are fairly complete. There are two or three slight breaks,
due to the unavoidable absence of Mr. Wakelin.
MIAS'REMENTS OF TREES.-The diameters of the trees (6 in-
ches above the bud) have been taken three times a year, making
7 measurements in all, beginning with June 7, 1909. The average
of all the trees in every plot is calculated each time, and in this way
i: is possible to make a fair comparison of the growth of the dif-
ferent plots. From these measurements it is found that the in-
crease in size during the fall and winter months (that is, from
about the middle of October to March) is very slight. From
March to June, and from' June to October. on the other hand, the
increase in size is considerable.
The average diameter of the 480 trees for the different dates is
June 7, 1909 -----------...---- -- 22.52 thirty-seconds of an Inch
October 20, 1)9 ------------ ---------- 24.18 thirty-seconds of an inch
March 1. 1910---------------------- 24.20 thirty-seconds of an inch
June 23, 1010---------- -- 26.90 thirty-seconds of an inch
December 6, 1910 -- ----------- _32.31 thirty-seconds of an Inch
March 22, 1911 ----------- ------ 33.11 thirty-seconds of an Inch
June 21, 1911-------------- -- 36.57 thirty-seconds of an inch
The increase in diameter in thirty-seconds of an inch, obtained
b) taking the difference between the averages of the plots for June
7, 1909, and those for June 21, 1911, is reported in Table XIV.
The table shows the fertilizer treatment that each plot has re-
ceived. Plots 46 and 47. both of which received the clean culture
treatment, stand first and second, while the other clean culture plot.
No. 48. stands seventh. Plots 35 and 36, which received floats con-
taining four times the amount of phosphoric acid in the standard
formula, occupy the third and sixth places. Plot 43, which re-
ceived no fertilizer. stands ninth in the list.
AVERAGE GAIN IN DIAMETER OF TREES FROM JUNE 7, 1909, TO JUNE 21, 1911
Standard. Clean culture.
Nitrogen from dried blood. Clean culture.
Phosphoric acid from floats (four times standard).
Phosphoric acid from floats, (four times amount). Nitrogen
from cottonseed meal.
Nitrogen from nitrate of soda. Clean culture.
Potash from low-grade sulphate.
1-2 nitrogen from nitrate of soda; 1-2 from sulphate of
1-2 nitrogen from cottonseed meal: 1-2 from nilphat-' of
Phosphoric acid and potash decreased by one-half.
Potash from nitrate of potash. (Balance of nitrogen from
nitrate of soda.)
Phosphoric acid and potash Increased by onii-halt
Acid phosphate, nitrate of soda, and hardwood ashes.
Phosphoric acid from steamed bone. (twice the amount in
Phosphoric acid (rom steamed bone.
Potash from murlate.
Standard, and air-slaked lime.
Standard. and ground limestone.
1-2 nitrogen from nitrate of soda; 1-2 from dried blood.
Phosphoric acid from floats (twice the amount in standard).
Phosphoric acid from floats.
Standard, and ground limestone.
Nitrogen from cottonseed meal.
Phosphoric acid from dissolved bone-black.
7 1-2 per cent. potash in June. 7 1-2 per cent. In October and
3 per cent. in June.
Nitrogen and potash Increased by one-half.
Phosphoric acid from Thomas slag. Nitrogen from nitrate
Phosphoric acid and nitrogen decreased by one-half.
Phosphoric acid from dissolved bone-black.
1-2 nitrogen from cottonseed meal. 1-2 from nitrate of soda.
Nitrogen from cottonseed meal. Ground limestone.
Phosphoric acid and nitrogen increased by one-half.
Phosphoric acid from Thomas slag (double amount). Nitro-
gen from nitrate of soda.
Nitrogen from dried blood.
Nitrogen and potash decreased by one-half.
Potash from kalnit.
Nitrogen from nitrate of soda.
1-2 nitrogen from sulphate of ammonia; 1-2 from dried blood.
Four times standard.
xxx Florida Agricultural Experiment Station '-^
Standard formula (for young trees): Ammonia, i per cent, from sut.
phate of ammonia; phosphoric acid, 6 per cent, from acid phosphate; potash,
6l per cent., from high-grade sulphate of potash. "Nitrogen from dried
blood" means that an equivalent amount of nitrogen in the form of dried
blood has been substituted for the sulphate of ammonia of the standard, and
so on. In the fall application, the potash In the standard Is Increased to 8
per cent., and the ammonia reduced to 21-2 per cent.
Fig. 3.-Experimental Orange Grove.-Plot 46. Standard fertilizer and
The plot that has made the least increase in growth is No. 4,
which received four times the amount of fertilizer in the standard.
This amount is the equivalent of 8 pounds per tree three times
a year, and is undoubtedly excessive for trees so young as these,
for they made hardly any June growth this year. Plot No. 3, which
received twice the standard, also stands low in the list, being
fortieth. It is not possible, at this date, to say whether the in-
jurious effect on these trees is due to any particular fertilizing
ingredient or to all of them together. There is the same luxuriant
growth of grass and weeds around these trees that is found around
other trees that have been well fertilized.
As a rule the trees that are making the greatest increase in
diameter are the ones that appear most healthy and are putting on
the most new growth.
.Inniul Report, 19ir
Fig. 4.-Experimenial ()range Grove.-Plot 30 Floats,
high grade sulphate if piotash.
cottonseed meal. and
;. 5.-Experimental Orange Grove.-Plot 43. No fer
Florida Agricultural Experiment Station
SOIL TANK INVESTIGATIONS
SETTING OUT AND FERTILIZING THE TREEs.-Work has been
continued with the soil tanks which were described in last year's
Report. They were opened to the rainfall on July 7, 191o; and on
July 15 one orange tree was set out in each tank. (These trees,
however, soon became infected with withertip and made but little
growth. It is probable that their presence had but slight influence
either on the soil or the composition of the drainage waters.) No
fertilizers were applied at the time of setting out the trees, as it
seemed best to first find out the composition of drainage water from
soil that had not been influenced by fertilizers.
I:ig. 6.--I',ur .,il tanks with young orange trees. June 9, 1911.
The original trees having died, they were replaced by healthy
three-year-old Valencia Late orange trees, on sour stock, on the
fourteenth of last February. A month later these were fertilized.
The tree in Tank I was given the equivalent of two pounds of a mixture
analyzing 5 per cent. ammonia; 6 per cent phosphoric acid: and 6 per cent
potash; made from sulphate of ammonia, acid phosphate and high-grade sul-
phate of potash.
The tree in Tank 2 received the same, and beggarweed will be grown in
this tank during the rainy season. -
The tree in Tank 3 received the same treatment as No. l, except that ni-
trate of soda was used as the source of nitrogen.
For the tree in Tank 4 dried blood was used as the source of nitrogen, the
other materials remaining the same as for No. I.
It will be observed that the phosphoric acid and potash are con-
stant in all the tanks, both as to amount and source of material,
and that the amount of nitrogen is also constant, but is derived from
different sources for three of the tanks. This treatment will be
continued from year to year, the quantities being increased with
Annual Report, 1911
the demands of the trees. We will thus be enabled to make a
fairly accurate comparison of the loss of nitrogen under the four
systems of fertilizing. The surfaces of Tanks i, 3 and 4 will be
kept clean throughout the year. The beggarweed which grows oin
Tank 2 will be worked into the soil. By this means we will be able
to study the effect of humus on the composition of the drainage
water, and also hope to collect some information as to the amount
of nitrogen which the beggarweed is able to take from the air.
RAINFALL AND COMPOSITION OF DRAINAGE WATER.-Water
began to come through the tanks on July 30o, and the first collection
was made on August i. During the year, eleven drainage samples
have been collected as shown in Table XV. The eleven collections
average about 23 gallons each per tank. From July 7, when the
tanks were opened, to May 23, the date of the last cullectiun, the
total rainfall was 35.71 inches. Computing, from these figures,
for the two-thousandth part of an acre, it is found that the amount
of rain-water falling on one of the tanks during this period was 49o
gallons. The average amount collected from each tank during the
same period was 250o2 gallons. It will thus be seen that only a
little more than half of the water that fell on the tanks was codfted
as drainage. It is probable that the amount collected would have
been somewhat less had a crop of grass and beggarweed been al-
lowed to grow over the entire surface, or had the trees that were
first planted made a normal growth. The trees that were planted
this year are growing well and have no doubt utilized much of the
water that has fallen on the tanks since they began to make new
We have made fairly complete analyses of all the samples
(it was thought unnecessary to determine iron, aluminium, and
silica); and the results, reported as parts of mineral constituents
per million parts of water, are given in Table XV.
It should be borne in mind that no fertilizers were applied
until March 14, 1911. Since the ground was dry at this time and
the drainage sample that was collected on March 15 had accumu-
lated previous to the application of the fertilizer on March 14,
it is clear that only the last sample, that collected on May 23, was
in any way influenced by the fertilizers. The rainfall between
March 14 and May 23 was 5.67 inches, but as this was fairly well
distributed, and mostly in light showers, it was not to be expected
that the sample of May 23 would show any great increase in miner-
al constituents. As a fact the total nitrogen was less in each sample
collected on May 23 than in the samples collected on March 15.
Since sulphate of ammonia was used on Tanks I and 2 and nitrate
of soda on Tank 3, materials which are readily soluble, we would
probably be justified in concluding that the rains were not heavy
enough to carry much, if any, of the fertilizers through. On the
COMPOSITION OF DRAINAGE WATER FROM Son. TANKS-PATS PER MILLION
Datwot o 0
Aug. 1-- 97.8. 581.0 168.3 .09 1.88 11.57 12.8 .131 49.8 84.7 7.281 U9
Aug. 6.. 70.1 518.0 807.0 .42 .72 4.40' 50.9 .21, 77.8 57.0 8.40 46.6
Aug. 15 ... 54. 488.5 818.6j .70 .99 8.141 86.6 .27' 79.0 61.8 3.12 89.1
Aug. 24 -- 88.6 321.5' 228.6 .16 .49 8.06 22.0| .23 53.4 89.8 2.49 25.7
Sept. 8 -- 100.2 249.5 152.0 .11 .281 2.80 14.1| .17 38.6 28.0 1.92i 17.9
Oct. 10 72.9 159.0 69.4 .00 .281 4.68' 8.8' .201 19.71 15.0 1.57 17.8
Oct. 19 1117 152.0 73.5 .00' .13 3.87' 5.1 .181 16.6 14.2 1.82 10.5
Nov. 29 -- 110.7 188.2 80.6 .00 .09 8.06 5.2 .07 17.9 13.6 1.10 9.9
Jan. 11 99.9 184.7 81.5 .00 .10 3.80 5.0 .10 17.5 14.8 .92 8.1
Mch. 15 -- 34.4' 149.5 74.4 .01 .12 8.95 5.7 .08 19.5 15.1' .54 5.1
May 2- 69.81 126.2 61.6 .06 .08 4.20 5.9 .10 16.8 18.6 1.02 10.2
Average -- 82.21269.2 146.4' .74 .391 4.87 26.8 .16 37.0 27.9 2.24 27.7
Aug. 1 --' 108.21 868.5 125.8
Aug. 6 76.8' 500.5 248.4
Aug. 15 --- 68.7! 514.0 298.0
Aug. 24 --- 89.6 378.0 268.9
Sept. 8 --- 909.8 189.5 119.1
Oct. 19 --- 103.9 113.5 74.8
Nov. 29 --- 106.3 145.0 87.2
Jan. 11 -- 102.2| 148.2 90.8
Mbe. 15 _- 87. 1W5.2 86.8
Mar 28 M 96 o8.0l 55.81
.191 44.2 26.4 7.10
.25 71.6 38.2 8.27
.25 87.56 42.5 2.81
.14 74.9; 33.2 2.68
.131 35.7i 16.8 1.40
.14 19.9 10.0 1.80;
.13 20.9. 10.5 1.04,
.061 23.2; 10.4 1.04
.07 23.0' 11.0 .88
.05 26.3 11.9 .50
.071 17.8 9.1 1.13
Average --l i. 1187I51111 40.5 1.5! 2.10 19.8
Aug. 1 =__ 107.2 424.0 184.7 .10 .58[ 6.711 59.8 .26 46.2 835.4 7.01 55.8
Aug. 6 8-- 78.1 529.0 869.8 .27 .371 2.96; 29.0 .26 79.3 60.7 8.83 49.0
Aug. 15 --- 66.4 469.7 828.5 .30 .84 2.82 22.3 .15 71.9 61.2 3.86 42.8
Aug. 24 --_ 91.7 300.5 185.8 .19 .27 2.290 18.0 .14 42.1 34.0 2.21 21.4
Sept. 8 _- 97.7 136.0 102.7 .15 .21 2.11 0.81 .13 21.6 17.8 1.731 14.9
Oct. 10 ___ 79.7 147.5 67.1 .03 .28 2.32 5.5 .10 14.9 12.8 1.61i 10.5
Oct. 19 -- 100.7 131.0! 75.0 .00 .13 1.28, 4.3 .14 15.3 12.8 1.44! 9.4
Nov. 29 --- 100.0 128.5! 82.4 .00 .08 1.76' 4.0 .07 17.0 13.6 1.66i 9.0
Jan. 11 ... 100.8 108.7 87.2 .00 .07 1.7& 4.8 .07 17.4, 14.5 1.58 7.4
Meh. 15 -_ 68.1| 128.5 51.8 .03 .13 L0911 4.8 .05 14.6 11.4 .57 4.0
May 23 102.9 96.2 39.8 .05 .08' 2.26! 4.81 .06 10.9 10.0 1.321 5.4
Average _- 91.41 240.9 143.1i .10. 2.51 14.9 .13 31.91 25.8 2.89 20.9
Aug. 1 ___ 110.4
Aug. 6 --- 67.3
Aug. 15 --- 61.2
Aug. 24 --- 87.0
Sept. 8 --- 95.5
Oct. 10 ___ 71.0
Oct. 19 --_ 109.8
Nov. 29 --- 105.7
Jan. 11 __. 100.9
Meh. 15 __ 29.6
May 28 __ 91.0
Gen. Aver- 86.2
50.8 11.071 98.1
88.4 9.08 90.9
100.7 9.24 76.7
48.8 5.80 48.1
28.7 4.11 87.2
21.1 4.40 8L1
25.0 4.46 21.5
80.1 4.12 19.5
26.8 8.46 15.1
21.1 1.58 7.2
18.8 2.84 18.2
41.8 5.42 41.2
28.6 8.04 2.8
r 284.5| 1A9 .i~2M
Annual Report, 1911
other hand, the phosphoric acid is slightly increased in the samples
from Tanks 1, 2 and 3, and the potash and soda are considerably in-
creased in all the samples of May 23. In view of the fact that the
more soluble nitrogen compounds did not come through in increased
amounts, it would seem that the increase in the phosphoric acid,
potash and soda may be attributed to the natural weathering of
the soil rather than to the leaching out of the fertilizers that were
applied. Tank 3 would seem to bear out this view, since it re-
ceived its nitrogen in the form of nitrate of soda, but the sample
of May 23 for this Tank shows a smaller increase in soda than the
samples from any of the other Tanks for the same date.
Loss OF NITROGEN.-Referring to Table XV it is seen that
nitrogen is lost in much greater quantities than any of the other
materials, the average of total nitrogen, calculated at NO-, for
the four tanks being 159 parts per million. This would be a loss of
nitrogen equivalent to 91o02 pounds of nitrate of soda per acre for
the period from July 7 to May 23. This nitrogen appears in the
drainage waters chiefly as nitrates, though there are also small
amounts of nitrites and of ammonia.
The loss of nitrogen is possibly somewhat greater than would
occur under ordinary field conditions, for the soil was thoroughly
stirred and aerated before it was placed in tanks, and abundant
warm rains followed, so that the conditions for nitrification were
exceptionally good. If these conditions do account for the unusually
large amount of nitrates that appear in the first four samples, this
certainly furnishes excellent proof of the value of stirring and
aerating the soil as a means of promoting nitrification. Light is
also thrown on the question of when the loss of mineral constitu-
ents is greatest. Since October 19, 1910, the rainfall has been com-
paratively light and well distributed, and the amount of water
passing through the tanks has been correspondingly small. Partly
as a consequence, the loss of fertilizing constituents is much less dur-
ing this period than it was during the rainy season. From this it
would appear that with the rainfall moderately well distributed, the
loss of fertilizing constituents is comparatively small. By far the
greatest loss comes with long-continued heavy rains.
It will be noted that in the case of the total nitrogen (and also
some of the other materials), there was an increase from the first
to the second, and, in some cases, the third sample, and then a gradu-
al decrease. This increase may be due to the unusual bacterial
activity, and the solvent effect of the resulting carbon dioxide on
the mineral constituents.
THE Loss OF POTASH AND PHOSPHORIC ACID.-The amount
of potash and phosphoric acid that was lost is very small in com-
parison with the nitrogen compounds, the general average per tank
being three parts per million of potash and .15 part per million
xxxvi Florida Agricultural Experiment Station
of phosphoric acid. The loss represented by these figures is equiva-
lent to 25 pounds of high-grade sulphate of potash and about 5
pounds of 16 per cent. acid phosphate, per acre. From this it might
appear to some readers that the loss of phosphoric acid is about
one-fifth that of potash, but this is due to the potash (KO20) being
calculated to a high-grade material. In parts per million, the loss
of phosphoric acid (P04) is only one-twentieth that of potash.
This small loss of phosphoric acid should not, however, be at-
tributed to a deficiency of this material in the soil, for a determi-
r.ation made on a sample from one of the tanks shows about twice
as much phosphoric acid as is found in the average Florida soil,
and about twice as much phosphoric acid as there was nitrogen in
the same sample. The low figure should rather be attributed to
the way in which phosphates are held in combination in the soil,
and would indicate that the loss of these materials through leaching
is very small indeed. On the other hand, we should not infer
that these phosphates are not available for plant growth; for on
this same land large magnolias and other forest trees were stand-
ing, not many months before. No determination of the potash in
these soils has yet been made, but there is good reason to believe
that there is a fair supply for normal plant growth.
Loss OF OTHER CONSTITUENTS.-Lime, magnesia, and soda
arc leached out to a greater extent than either potash or phosphoric
acid. but the loss of these is far less than that of the nitrogen com-
pounds. The general average losses per tank are 36.9, 28.7, and
27.3 parts per million of lime, magnesia, and potash, respectively.
The loss of lime is equivalent to 275 pounds of carbonate of lime
per acre for the ten months covered by this work. For a soil that
is naturally deficient in available lime this loss is considerable.
With regard to the needs of the plant for mineral food it is not
probable that the loss of magnesia and soda is serious; but as basic
materials which have a definite value as correctives for soil acidity,
their loss may have an important bearing on plant growth.
No satisfactory explanation can be given for the large amount
cf sulphate which appears in the samples from Tank 4, on September
8 and afterwards. As has already been stated, no fertilizers were
applied until March 14, 191 I. No unusual increase of any of the
other mineral constituents occurred at this time.
In nearly every instance the average figures for Tank 4 are
considerably higher than those for any of the other tanks. In
taking out the soil for this tank (this same soil being afterwards
used for filling the tank) charcoal and bits of burnt wood were found
in the first foot or two, indicating that a stump or pile of logs or
brush had been burned there when the land was cleared a few
months before. The ashes doubtless made the conditions for nitri-
fication more favorable, with the result that more of the nitrogen
Annual Report, Izg
of the organic matter was converted into nitrates than in the other
tanks, and these nitrates appear in the drainage water. The pres-
ence of ashes would also explain the high phosphoric acid, potash,
lime, and magnesia in this tank. This apparently affords an
illustration of how basic materials applied to our acid soils promote
nitrification, and perhaps hints that we might apply them at some
other time than at the beginning of the rainy season, unless there is
a vigorous crop on the land to take up the nitrates that are formed.
MOISTURE DETERMINATIONS.-On account of the excellent
drainage provided in the soil tanks, it seemed possible that the soil
inside might be drier than similar soil outside. Accordingly moist-
ure determinations were made on samples from the tanks and from
the corresponding plots outside, at five different times, beginning
on January 30, 1911. Samples composed of two borings, taken
from the surface to a depth of 9 inches, were collected from each
tank, and from each corresponding plot outside. The amount fi
soil thus taken was usually from 150 to 200 grams. An effort
was made to keep the soil in about the same condition at both
places. However, at the time of the first three samplings, the soil
outside was somewhat more compact than in the tanks, and a few
weeds had commenced to grow. It was broken up and raked over
Before the other samples were taken. The results are reported in
MOIST:I-R" DETERMINATIONS FROM SOIL TANKS, AND FROM CORRESPONDING OUTSIDE
Average for 4 Average for 4
Date tanks outside plots
Per cent. Per cent
January 30 -- -.... .... .. 7.10 5.05
February 2 ------------ 6.82 p 5.80
February 7.----------- 6.65 5.47
May 31 --------------------- 7.00 7.15
June 14 -------------------------- 5.91 6.34
General average ------------------- 6.70 6.14
Other determinations will be made; but if we may judge by
the results thus far obtained, it would seem that the perfect drain-
age secured in the tanks will not prove a disadvantage so far as
moisture conditions are concerned.
On March 24, samples of soils were collected from groves in
Orange Hammock, Marion county, representing some 30 to 40
acres. This soil is composed chiefly of a coarse brownish-red sand,
Florida Agricultural Experiment Station
and contains little organic matter. Nitrogen determinations have
been made of these samples, and the results are reported in Table
X TABLE XVII
NIToGENN, PaOSPHORIC ACID AND POTrAsH I Sons AND SUBson.s
Grove Ab 5 acres .0216 .0487 .0301 0 to 9
.0136 .0442 .0243 9 to 21
.0060 .0284 36 to 48
.0126 .04 .05250243 9 to 21
Grove D, 15 acres-- .0280 .03248 0 to 9
.0128 .0327 9 to 21
Grove D, 15 acres- .0289 .0481 Oto 9
.0163 .0471 .... 9 to 21
Virgivn Bammock.- .0515 .0481 ... 0 to 0
Phosphoric acid by mag:eslum nitrate Ignition method.
Potash by J. Lawrence Smith fusion method.
From these figures it is seen that the nitrogen content is quite
low in these groves, there being only about one-half as much in
the surface 9 inches as is found in virgin hammock of the same
type of land. These soils are evidently deficient in humus, and
would no doubt respond to a treatment that increased the supply
of this material. If beggarweed could be grown and left to decay
on the land, it would not only furnish more nitrogen directly, but
would also help to retain the plant food that is already present.
The phosphoric acid content of the surface soil does not vary
greatly from the average soils of the State. It is worthy of note
that as we go down deeper in the soil the phosphoric acid decreases
but slightly, and with the exception of the seven-acre grove there
is more phosphoric acid in the cultivated land than in the virgin
hammock. This hammock, it may be stated, is a dense forest of live
cak, hickory, bay, and undergrowth of various kinds. On the basis
of the above analyses, an acre of the soil of these groves to a depth
of four feet would contain about three and a half tons of phos-
phoric acid. This, if made available, would produce many crops
of oranges. The introduction of more humus and an occasional
application of lime in some form to the soil will help to make this
phosphoric acid available.
Annual Report, 19ri xxxix
We have, by correspondence, newspaper articles, and lectures,
continued to give some attention to correcting acid soils in con-
nection with citrus growing.
An air thermograph has been placed on the plot of ground near
the soil tanks, and a continuous temperature record is being kept in
connection with this work.
Another set of soil tanks is now on hand, which will be in-
stalled as soon as possible after the rainy season is over.
In all the work I have had the faithful and efficient co-operation
of Assistant Chemist, Mr. S. E. Collison.
A. W. BLAIR,
Florida Agricultural Experiment Station
REPORT OF ENTOMOLOGIST
P. H. Rolfs, Director
SIR: I submit herewith a report of the work in Entomology
for the year 1910-11.
FUNGUs DISEASES OF WHITEFLY
GAINESVILLE.-In the grove of Mr. B. F. Hampton observations
were made throughout the year on the progress of the fungus dis-
eases under the apparently adverse conditions noted in last year's
Report. On August 19, 1910, the following notes were taken:
Estimated that (for main grove of 450 trees) there is about one whitefly
larvai per leaf, but very little fresh fungus has developed; only a few new pus-
tule- were observed here and there. But there is still plenty of old fungus in
the form of faded and weathered pustules, especially in the few tangerines, Sat-
sumas and other trees only slightly defoliated during the previous winter.
Good new growth developing, but there is no fruit except on the Satsumas and
the few tangerines.
On the 50o or more Satsumas set out as a small grove, there are about two
larvae (all stag,- per leaf. "Natural mortality" prevalent on ohl leaves fol-
lowing frost of pruvius winter. There is much newly developed red Ascher-
sonia and some brown fungus on the new growth in some of the trees; a few
to sometimes 2o pustul, per leaf. The cover crop of weeds is growing tall
and rank. man high, and .11 as the trees.
These observations together with others lead me to believe that
frost may bring on conditions resulting in the death of many larvae,
frequently 70 to 8o per cent., and more. The "natural mortality"
frequently seen in the spring and summer broods of larvae may be a
When this grove was again visited in the latter part of Septem-
ber, 1910, the Satsuma grove (about 50 trees) might have been
described as a jungle of tall cover crop and trees, ideal for fungus
growth. The red Aschersonia was thriving perfectly: there was
only a little sooty mold, and the mortality among the whitefly
larvae was at least 90 per cent. During the winter and after the
weeds were cut down, the Satsuma trees held their fungus well until
much of it was lost by the shedding of leaves accompanying the
In May 1911, the following conditions were noted in the main
grove of 450 trees:
Grove looks good. There has been a heavy bloom, but perhaps only 300
boxes of fruit set. Foliage on many trees undeveloped, indicating lack of fer-
tilizer, the trees not having been fertilized before May. Average of about six
whitefly larvae per leaf on new growth. Little or no sooty mold except on a
few trees where whitefly larvae by the dozen per leaf. Red Aschersonia has
sot begun to spread to new growth, and the very small amount of fungus from
last year is badly weathered. There is also a little brown fungus. Spring is
Awsual Report, 1911
very dry. Clean culture with harrow. Beginning with the zgth, the grove was
sprayed by the owner with a miscible oil for the purpose of reducing the white-
fly; but spraying was begun a little too late as adult whiteflies were beginning
to swarm. Several rows were sprayed with Whitefly Formula IV. This con-
sists of one gallon whaleoil soap, one gallon water and two gallons Junior Red
Engine Oil, 25 degrees Baume. The inventor is Mr. W. Others, Field
Agent of the Bureau of Entomology, stationed at Orlando, Florida.
The small Satsuma grove had considerably more whitefly daring May, per-
haps an average of two dozen on each new leaf. There was only a little old
fungus here and there, but some new was beginning to develop. Clean culture
is practised during spring and there is plenty of fruit set. The owner was ad-
vised to spray this grove with the miscible oil in order to reduce the numbers
of the whitefly. Suitable weather conditions prevailing, and with the growth
of a tall cover crop, there is no doubt, however, but that the red and brown
fungi will control the whitefly during the coming summer as they (principally
the red) did last summer.
To sum up the experiments and observations in the Hampton
grove, the writer concludes that in order to subject the whitefly to
a satisfactory degree of control by the use of the fungus diseases
these nx ill necessarily have to be re-introduced or spread in the larger
grove every year or two and perhaps also occasionally in the Sat-
suma grove. Defoliation by frost, and dry weather, will now
and then militate Lo the disadvantage of the fungi. Then it may
also become necessary io supplant the fungi by spraying with in-
The fifteen or twenty trees of Mr. James Cellon were so badly
injured by the frost of December 29 and 30, 1909, that the white-
fly and fungus became reduced to a very small quantity. (Sce also
Naw SMYRN .\.-Three visits were made to this place to note
the whitefly-fungus conditions. The following conditions were
noted in Ronnoc Groves 1, 2, 3, on August 12, 1910.
Some Sateuma trees have the most red fungus, otherwise there is only a
small amount of fungus, the most anywhere amounting to perhaps 20, mainly
immature, pustules per leaf. The amount of fungus, as a whole, is disappoint-
ing; and I was not informed that any spraying of fungus spores had been
carried on during this year. The trees have lost some wood, and the crop will
be about two-thirds. There is a thin coat of soot on the fruit and leaves.
On December 22, 1911, the following conditions were noted
for the Ronnoc Groves:
Nos. i and s.-Hundreds of whitefly larvae; red and brown fungus and
"natural mortality" equally effective; "natural mortality" even more so than
the known fungus diseases. More sooty mold now, but storm of October has
washed off large quantities, causing trees to look brighter. There is too much
whitefly, and I could wish that the fungi had been more effective this year.
No. 3.-On November I to 4 this grove was sprayed with a proprietary
miscible oil, with good results. This spraying resulted, not only in killing a
high percentage of the whitefly larvae, but also in loosening the sooty mold
so completely that it lay drifted like soot beneath some large trees that had
been very black with this mold. Trees now appear clean; also the fruit. There
is plenty of red and some brown fungus apparently uninjured by the spray.
Florida Agricultural Experiment Station
When visited again on April 2, 1911, about two-thirds of the
whitefly had swarmed. The effects of spraying grove 3 in Novem-
ber were still apparent. Not only was the grove remarkably free
fiorn sooty mold, but the small amount of whitefly swarming in
this grove was the subject of comment by the foremen. Large
numbers were, however, migrating from the other groves, so that
complete re-infestation was inevitable. The writer therefore ad-
vised that all the groves be sprayed with the miscible oil, or some
emulsion, during the latter part of April, in order 'to reduce the
number of whitefly larvae of the spring brood.
The following notes were made on the R. S. Sheldon Grove:
August 12, iglo.-Trees swarming with adults. Some fungus red and
brown, as much as 20 pustules per leaf, in some parts of the grove (about x6o
trees, mainly orange, few grapefruit); but only a sprinkling of fungus gener-
ally. Trees have lost some wood and are not so low and spreading as they
were. Crop of fruit is below average. Trees and fruit are covered with sooty
mold, and will become very sooty if left untreated. No treatment of any kind
has been applied to date. The fungus diseases of scale insects are abundant.
The grove should be given another application of the whitefly fungi this month
Following the visit of August 12, Mr. Frank Stirling of De-
Land, was engaged to treat this grove with fungus. This was done
by the spore-spraying method on August 19, using both the red and
the brown fungus.
December 21, 1910o.-There is apparently a full crop of whitefly larvae on
the leaves. The "natural mortality" of these is very great here and there. The
red fungus is more abundant, and there are dozens of the red fungus pustules
per leaf in some trees. Some of this fungus is infected with the hyper-parasite,
Cladosporium herbarum. There is some brown fungus scattered here and
there. One tree back of house has apparently a full crop of brown fungus
with spores; the estimated mortality of the whitefly being at least 80 per cent.
As a whole. I had expected a much larger infection with the fungi, following
the treatment on August 19. Some trees have lost considerable wood and
foliage, those at north end even as much as one-half of their leaves. Trees
look clean, however, the storm of October having washed them; but there is
some sooty mold. Scales have increased in a few trees.
April 2, 1911. Plenty new foliage. Whitefly is swarming, and complete
infestation is inevitable. Fungi. red and brown, are present, but shall recom-
mend re-spreading same for this grove.
It is evident that in order to get the best results, the fungus dis-
eases should be re-spread occasionally and also supplemented with
contact insecticides, especially in fall, and also in spring. Several
conditions may conspire to reduce the efficacy of Jfie fungi, or
greatly reduce them in quantity. Principal among these are defoli-
ation of the trees by frost and dry weather.
It has been maintained by some that re-spreading the fungi into
trees that already have fungus does not increase their effectiveness,
and that the amount of fungus already present is the most that can
Annual Report, iyu
develop under the conditions then existing. While some investi-
gations appear to bear out this conclusion, others have distinctly
shown that the amount of fungus may be materially increased by
introducing more fungus. Considering the cheapness of spreading
fungus by the spore-spraying method the average grower certainly
can afford to take chances on increasing the effectiveness of the
fungi by re-spreading them several times during the period of
summer rains, and earlier when conditions are favorable.
In this connection, the experience of Mr. Frank Stirling of De-
Land, who, with assistants, has treated over one million trees with
fungus spores during the past three years, is of interest. Under
date of July 16, 1911, Mr. Stirling writes:
My observations and experience clearly show that repeated sprayings of
fungus spores onto whitefly-infested trees generally give quicker results by
far than only one spraying.*** For instance, when the third brood of larvae
is in the proper stage on the new growth that extends beyond the older growth
with the old fungus, I have found that by spraying that new growth, quicker
and better results are obtained than by waiting for the fungus already on the
trees to spread to the new growth. I have had'occasion to test this time and
time again as I am spraying groves one, two or three times each year.*** I
will mention one grove in particular which was sprayed once two years ago;
now that grove has plenty of fungus and plenty of whitefly. Another grove
which I sprayed at the same time once every thirty-five days was cleaned up
by the next winter and now has no fungus whatever, owing to the fact that
there was no food (whitefly larvae) upon which it could live. These two
groves were about in the same condition when I sprayed them and are situ-
ated about three miles apart.
DELAND.-The following observations were made at DeLand
on August 13 and December 20, 1910. The fungus diseases of the
whitelly continue to thrive well in many groves, and are giving
a marked degree of relief.
Some spraying operations with the Target Brand insecticide
carried on by Mr. H. B. Stevens in the Stetson Groves during May
and October are of interest. Observations made by Mr. Stevens
and Mr. Frank Stirling, both close observers, are to the effect that
fungus will not take well on foliage previously sprayed with this
insecticide and that it becomes necessary to wait for the develop-
ment of new foliage before introducing fungus. On the other
hand, fungus taken in spring from trees that had been sprayed
with this insecticide the fall before made good growths when sprayed
into other trees.
The immediate results of this spraying were considered quite
satisfactory. The writer made no estimate of the percentage killed
by the spray, but Mr. Stevens reported that the sprayed fruit
washed much cleaner and easier than fruit not sprayed.
The grove of Mr. C. F. Spaulding, near DeLand, showed a re-
markable degree of fungus efficiency in checking the whitefly.
Florida Agricultural Experiment Station
While the crop appeared to be a small one, it probably required
but little washing. In a letter dated January 14, 1911, Mr. Spauld-
ing stated that he treated the grove with red and brown fungus
early in July, 191o, employing a power sprayer and a pressure of
16o-175 pounds to apply the mixture of spores and water.
The wholesale manner in which the fungi are employed in the
vicinity of DeLand is due, in part at least, to the way in which
Mr. H. B. Stevens delights in trying out anything that appeals to
him as useful. Prompted, in part at least by Mr. Stevens, Mr.
Stirling, upon whose work report was made in 1909 and 1910, has
continued applying the fungus diseases, and during 1910o has treated,
with the help of assistants, between 750,000 and 8oo,ooo trees at
a cost -of about two cents per tree and less. This year (1911) Mr.
Stirling is again busy re-spreading the fungus, with headquarters
at DeLand, while Mr. E. B. Stevens, a former associate of Mr.
Stirling, has established headquarters at Lakeland.
WINTER PARK.-The.fungus diseases of the whitefly (red, yel-
low, brown and white-fringe fungi, with some cinnamon fungus)
continue ti thrive well at this place. In the groves of Mr. William
C. Temple. the degree of relief from the bad effects of the whitefly
is quite adequate. Notes made in November 1910, in the home
groves of Mr. Temple, indicate great efficiency of these fungi, al-
though the results were not perfect, and there was some whitefly
and sooty mold present. During 1909 and 1910, Mr. Temple has
had the fungi spread once or twice each year.
The grove of -Mr. J. F. Adams continues to thrive well, with the
fungi as the only repressive measure employed. This is the grove in
which Director P. H. Rolfs discovered the yellow Aschersonia
ST. PETERSBURG.-This place was visited op December 8, 1910o.
There has been no improvement in the whitefly situation here. The
whitefly continued to spread during 1910o, with the usual results.
A rather extensive distribution of fungus, obtained from Manatee
County (reported as 30,000 leaves), was made by the Board of
Trade early in the season. No very definite results were noted.
That other repressive measures besides the fungus diseases are nec-
essary at St. Petersburg has been evident for several years.
In the Moss Ridge Grove, owned by Mr. William E. Heathcote,
the brown fungus (Aegerita webberi) had held its own better than
the red (A. aleyrodis). There was a small amount of red as in
the previous year, but the brown fungus had increased (a few
dozens of pustules per leaf) especially in the southeastern part of
the grove among the Tardiffs. These trees look comparatively
well 'and are bearing fruit, as are also the grapefruit trees. The
Annual Report, ipit
cinnamon fungus (Verticillium heterocladum) also continued to
thrive in some of the grapefruit trees. Tile north part of the grove,
especially where the tangerines are. continues to suffer most.
Whitefly larvae (A. citri and A. nubifera) are abundant: the
cloudy-winged species (A. nubifera) being present in larger num-
bers than heretofore. The grove as a whole, in so far as its life is
concerned, is holding its own against the whitefly and scales, be-
cause of the fungus parasites of these insects, and is in about the
same condition that it was a year ago (Report 1910). The crop of
fruit was small and considerably sooted. The results from fungus
alone have not been satisfactory here to the extent that the grove
could continue to produce adequate crops of fruit.
SUB-PENINSULA.-The whitefly-fungus conditions here are
about the same as at St. Petersburg, and as they were described
for last year (Report 1910). On December 5 and 6, 1910. groves
were visited to the east of Clearwater and about Bellaire, Largo,
Anona, and Seminole. Groves that had suffered previously from
the attacks of whitefly and scales were improving. This improve-
ment in the general appearance of infested trees is doubtless co,-or-
dinated with the establishment of an equilibrium between the in-
sects and their natural enemies (whether fungus, hlcterial, or
insect), which lessens the amount of infestation to a point where
the trees begin to recover.
While the fungi have so far not fulfilled expectations on the
Sub-Peninsula, indications are that a reasonable degree of relief
will be obtained in several places. I will therefore give some notes
taken in the grove at the home of Mr. Bernard Kilgore, west of
The grove consists of grapefruit, tangerine and orange. A. citri and A.
nubifera are present. The red, yellow, brown, and white-fringe fungus
parasites of the whitefly are present in quantity, and are thriving. The red-
headed, white-headed, and black scale fungus parasites are also plentiful. The
tangerine trees look well and are bearing a fair to a good crop. The grape-
fruit and oranges have some crop. Trees are ten to fifteen feet high and look
well. The fruit looks clean and there is but little whitefly. The whitefly fun-
gus was introduced by the spore-spraying method.
OTHER PLACES.-Apopka, Bartow, Boardman. Candler, Eustis.
Emporia, Grasmere, Hawks Park, Kissimmee, Leesburg, Monti-
cello, East Palatka, Orlando, Pierson, Plymouth, Tampa, Tanger-
ine, and Winter Haven were visited during the year, and observa-
tions made upon the whitefly and its diseases, when these were
present. At Apopka, Mr. Frank H. Davis expects to depend upon
the fungus diseases of the whitefly, principally the red and brown,
as well as the cinnamon and white-fringe fungi. At Bartow, Mr.
Florida Agricultural Experiment Station
H. C. Conner, after several years experience with the red and
brown fungi, believes that they will give him the necessary relief.
At Grasmere, Mr. E. M. Strong has been getting good results with
the red fungus. At Kissimmee, a very prolific growth of brown
fungus with some red had developed during 1910 in the little grove
of Mrs. Addis. Mrs. Addis stated that during the spring of 19o9,
she had pinned a few leaves with fungus into each tree. In the low-
spreading, and more vigorous trees, the fungi (principally the red
and brown, and white-fringe) are doing well at Kissimmee; in the
taller, less vigorous trees, they are not doing so well. At Leesburg,
the fungi (principally the red and brown) have done well in some
small groves, in others not. At East Palatka, in E. W. Johnson's
place, the red fungus and the brown were doing well, but the frost
defoliated and injured the trees in December, 1909, and consequent-
ly there was hardly any fungus present in November, 19to. At
Pierson, several growers have learned how to employ the fungi,
and expect to depend upon them for relief.
CULTURE OF RED ASCHERSONIA.-During the year, a number
of requests came for artificial cultures of fungus. Several growers
wished to get these in order to obviate the danger of introducing
citrus diseases by importing fungus from other groves. Others
desired the cultures as a source of supply early in the season when
natural fungus is sometimes scarce. Arrangements were finally
made permitting the Entomologist to use about twenty-four dollars
from the Farmers' Institute Fund to pay for the expense of grow-
ing a limited quantity of the Red Aschersonia. In all, about 130
cultures were successfully grown 'in one-half pint, pint, and quart
bottles. On July 5, fifty bottles of cultures were expressed to Mr.
A. F. Wyman of Bradentown; and sixteen each respectively to
Messrs. Frank Stirling, DeLand; E. B. Stevens, Lakeland; D. T.
McCarty, and J. D. Almond, Fort Pierce; and Wm. H. Maxwell,
GERMINATION TESTS OF RED AND YELLOW ASCHERSONIAS.-
During January and February, 1911, Mr. U. C. Loftin, Laboratory
Assistant, made some germination tests with the spores of these
fungi. The purpose was to determine, by laboratory tests, whether
certain insecticides were detrimental to the germination of the
spores. The effects of a polished and a dull copper vessel were
tested. Whale-oil soap and a proprietary insecticide were also em-
ployed. Clean citrus leaves were obtained, washed, and allowed
to dry. Small quantities of the insecticides were mixed in the fol-
lowing proportions: whale-oil soap, one pound to four gallons of
water (for the red fungus, one pound to two gallons, by mistake);
kerosene emulsion, one part in 15; Target Brand Insecticide, one
Annual Report, 1911
part in 50; Schnarr's Insecticide, one part in forty. Spores of the
fungus were collected from about fifteen pustules and placed in a
watch-glass with sufficient water to make the mixture of spores
and water of the consistency of cream. Several drops of each in-
secticide were then placed on the leaf; a drop of the mixture of
spores and water was added to the drop of insecticide and the whole
allowed to dry for about twenty hours. A drop of five per cent.
glucose in water was then stirred upon each dried spot of insecti-
cide and spores, and hanging-drop cultures on slides made of this
In making the tests with the copper vessels, tap-water was al-
lowed to stand for two hours in a polished copper vessel, and also
in one of unpolished copper. This water was used to make five per
cent. glucose solutions, from which hanging drop cultures of the
spores were made.
The results are shown in the following table.
In computing the percentages, the germinating spores and those
not germinating were counted in three fields of the microscope
from each drop. In the second test new and fresher fungus ma-
terial was obtained. The third test in the table was with fresh red
There was germination both in the soap and the Schnarr's
The results with the copper vessels are contradictory and the
experiment needs repetition.
EXPERIMENTS WITH FUNGUS SPORES
Treatment Total number of Percentage of
with spores observed germination
Polished copper 201 70
Yellow Fungus Dull copper 214 8
Check 306 43
Polished copper 15 (0)
Yellow Fungus Dull copper 53 92
Check 220 76
Polished copper 50 20
Dull copper 213 29
Red Fungus Check 159 62
Soap 57 74
Schnarr's 14. (57)
FUNGUS IN COLD STORAGE.-Since the results on the cold sto-
rage of red fungus reported last year were indecisive, another lot
of fungus was placed in cold storage in January and February,
1910. Leaves bearing red fungus were exposed to the air in the
laboratory for about a week, when they appeared dry. They were
Florida Agricultural Experiment Station
then packed in tin cans, placed in a burlap bag, and suspended
from the ceiling of the cold storage room of the Diamond Ice
Factory at Gainesville, immediately below the frost-covered am-
monia pipes. The leaves were removed from cold storage on
August 18, 1910o, after about seven months, and found to be in
good condition. Some dried leaves that had been left in paper sacks
became wet and rotted, as had happened the previous year. Hence
the necessity for cans to protect the leaves from damp. Fresh
leaves, whether placed in tin cans or not, were found to mold, or
otherwise change, unless kept at a lower temperature than that of
the cold storage room.
Two days after having removed this fungus from cold storage,
spores from it were sprayed into some privet bushes in town,
into a grapefruit tree, and into some small sour orange stock in-
fested with whitefly (A. citri). Some privet bushes were also
sprayed with spores of fresh fungus as a check. The spraying on
the privet hedges gave no satisfactory results, either with the
cold-storage fungus or the fresh fungus. This was in part due to
the hedges shedding a large portion of their leaves soon after spray-
ing. The infection of the whitefly larvae in the grapefruit was
sufficient to show that at least enough of the fungus spores were
alive to make it worth while to use them for infection purposes.
There were a few to a dozen growths of fungus pustules on many
leaves examined. More fungus developed on the small sour orange
trees, but none on some neighboring sour trees, which had not been
treated, and were used as a check.
Laboratory tests demonstrated that the spores from the fungus
kept in cold storage germinated as readily as spores from fresh
One lot of leaves kept in cold storage had some of the brown
as well as the red fungus of whitefly present. The brown fungus
developed in the trees treated with this lot. This shows that the
brown as well as the red fungus can be kept alive in cold storage.
It has been demonstrated that spores of the red and brown fun-
gus parasites of the citrus whitefly can be kept alive in cold storage
for about six months. It is therefore recommended that those who
expect to use fungus early in spring or summer should place a
plentiful supply in cold storage. The fungus-bearing leaves should
be dried in shade a week or ten days, put into tin cans (coffee cans,
baking-powder cans, etc.) and placed in cold storage. For large
quantities, tin lard cans would be suitable.
The best time to place the fungus in cold storage is in the late
fall and early winter, before the fungus begins to peel from the
leaves. December and January are indicated; February is also a
Annual Report, ip9
Experiments with the yellow fungus have not been carried on,
hence its keeping qualities in cold storage are not known. But
since it is so nearly like the red fungus in all respects except color,
there is little doubt but that it can be kept alive as well as the red.
SPOROTRICHU..-In the Report for 1909, p. xxxvi, a species
of Sporotrichum was reported as occurring on both dead adult
whiteflies and larvae. The two cultures referred to in the same
report were applied during July, 1909, in Mr. James Cellon's trees
near Gainesville. The mass of fungus with spores was mixed with
water, strained and sprayed into two citrus trees and a chinaberry
tree swarming with adult whiteflies. No infected flies were dis-
covered later, although looked for at successive intervals of 15,
24, and 40 days; nor during 1910 and 1911, although several ex-
aminations were made.
During April, 1910. several cultures of Sporotrichum globudi-
ferum (Chinchbug fungus) were grown on sweet potato in wide-
mouthed bottles. The inoculating material was obtained from a
culture grown by the Plant Pathologist, H. S. Fawcett, and was
of the second or third artificial generation. During June, one of
these cultures was sprayed into some small citrus trees near the
Station greenhouse, and another culture into some privet, all
swarming with whitefly (A. citri). Several cultures were also sent
to correspondents in the State who were willing to spray the
spores into trees swarming with whitefly.
After several days a few flies were found in the trees treated
near the greenhouse, that had a grayish fungus, like Sporotrichuan,
on their backs at the base of the wings. As the specimens were lost,
the fungus could not be identified. One correspondent, Win. H.
Maxwell of Titusville. to whom some of this fungus had been
sent, reported later, in July 19Tq, as follows:
It appears to me that this fungus attacks the fly on the back. right at the
butt of the wings The fly that I found with this whitish lump on the back
was sluggish. I also found some dead and some nearly dead.
No specimens were received from this correspondent. Later,
in August 1910o, the writer had occasion to examine some trees at
DeLand that Mr. Frank Stirling had treated with chinchbug fun-
gus from the same cultures. Some dead adults brought to the
laboratory were found to be infected with a Sporotrichum. but
the species was not determined.
SOAP AND SPRAYING MIXTURES
SOAP FOR SOFTENING HARD WATER.-Considerable difficulty
has been experienced by growers who have to use artesian or other
Florida Agricultural Experiment Station
hard water in mixing oil emulsions and miscible oils. The general
advice to "break" the water with carbonate of soda or caustic soda,
does not always seem to succeed. As ordinary soap is immediately
precipitated as an insoluble compound by the mineral in hard water,
soap might be suitable for softening water intended to be used for
mixing insecticides. A series of tests was therefore planned and
executed, mainly by Mr. Loftin. As the tap-water was found to
be sufficiently hard at times to cause small quantities of oil to rise
to the surface when mixed with emulsions and miscible oils, tap-
water was employed in some of the tests. Several gallons of es-
pecially hard water from Sanford were also used, which was rich
in chlorides and magnesium. Tests were also made by further
hardening the tap water with calcium nitrate, using 3 to 6 drops
of a saturated solution to about 4oo cc. of water. Good's Potash
Whale-oil Soap No. 3 was used to soften the water. The following
insecticides were tested: kerosene emulsion, one part to nine of
water; whitefly formula IV; a proprietary emulsion; and a pro-
prietary miscible oil, one part to forty-nine parts of water. In every
test made, when sufficient soap had been added to the water, the
resulting mixture with the insecticide was perfect and would re-
main so for days.
The simplest test for determining the necessary amount of soap
appears to be the feeling of slickness or soapiness of the water, and
its lathering qualities, after the soap has been added and dissolved.
If, when some of the mixture of soap and water is shaken in a
bottle or a bucketful of it poured back into the barrel or tank, the
lather or foam soon disappears, the quantity of soap is insufficient,
and more must be added. If these tests leave it doubtful that the
amount of soap added is sufficient, a small quantity of the mixture
of soap and water may be tested by adding some of the emulsion
or miscible oil to it. If, after half an hour, free oil begins to col-
lect at the surface, the water is still hard and more soap must be
added. The whole amount of water, barrelful or tankful, must
be thus treated with the soap before the insecticide is added, and no
untreated water may be added after the insecticide has been mixed
in, because the mineral in the untreated water will cause the break-
ing down of the emulsion. In one or two instances growers failed
to observe this point, with the result that free oil accumulated at
the surface. Neither will adding the soap to the unmixed insecticide
instead of to the water, give the results desired. The amount of
soap necessary to soften a certain quantity of water will, of course,
vary with the degree of hardness of the water. The Gainesville
tap-water required about a pound of soap to fifty gallons. This
water was found to vary in hardness. Thus when the water is
Annual Report, 1911
taken from Boulware Springs, none or hardly any softening was
necessary; while, when this supply became mixed with water from
the artesian well, it required about a pound of soap to fifty gallons.
On the other hand, some artesian water near New Smyrna required
about three pounds of soap to fifty gallons to soften it. It may
therefore be stated that in order to soften water with soap, from
one to three pounds of soap should be used to fifty gallons of water.
Any slight excess of soap would only add to the strength of the
insecticide, and improve its covering properties, especially when
applied to immature leaves. Whale-oil soap was used, but any
other soap would probably do as well. In applying this method of
softening hard water, the amount of soap necessary to soften a
certain quantity of water should first be determined and then the
proportionate amount added each time. Any emulsion, like kero-
sene emulsion or Whitefly Formula IV., soon begins to rise to the
surface like cream when it is allowed to stand. This is character-
istic of emulsions and does not indicate that the mixture has gone
bad. Stirring the mass will again produce a uniform mixture.
SODIUM CARBONATE, CAUSTIC SODA, AND BORAX.-Sodium
carbonate, (sal soda, or washing soda), was also tried at the rate
of about one pound to fifty gallons of water. Some good results
were obtained, especially when the mixture of water and soda was
allowed to stand for about one-half hour, to allow ie soda to act
upon the mineral. The success was less certain than with soap. As
in the case of soap, the soda or other softening agent employed must
be mixed with the water before the insecticide is added. Caustic so-
da was also tried; just enough of a five per cent. solution being ad-
ded to make the water feel slick to the touch. Some success was ob-
tained, but as in the case of sal soda, generally only after the mix-
ture of water and caustic soda had been allowed to stand for some
time. With kerosene emulsion, the presence of caustic soda in
the water resulted in oil rising to the surface, even when water
was used which did not cause this.
Borax gave no beneficial results, the oil rising to the surface
as readily as when no softening agent had been added.
Carbonate of soda and caustic soda will soften certain kinds
of hard water, and it is not a difficult matter to determine when
they will do so. Some of the water to be tested should be placed
in a colorless bottle and then treated with a small quantity of the
softening agent. If a cloudiness appears, then the softener is caus-
ing the mineral to be precipitated. If no cloudiness appears in the
water decide at once to employ soap, as the other softening agent
is having no effect. Or some of the insecticide may be added to
the treated water to see if, after fifteen or twenty minutes, any free
oil will rise to the surface.
Florida Agricultural Experiment Station
LIME-SULPHUR, SODA-SULPHUR, AND SULPHUR WITH INSECTI-
CIDES OF WHITEFLY.-Twigs of Satsuma trees infested with white-
fly (Aleyrodes citri) were dipped during March, 1911, into com-
mercial lime-sulphur solution diluted i to 30o. The whitefly larvae
were in the thickened fourth larval and pupal stages. Apparently
1no larvae or pupae died from the application of the lime-sulphur
solution. They were found to excrete honeydew like untreated
specimens. Other branches, with the whitefly larvae in all stages,
sprayed with lime-sulphur and soda-sulphur, i to 30, showed no bet-
ter results. The mortality of the larvae was so low that it was not
considered worth while to determine the percentage killed. It is
cf course possible that with the whitefly larvae in their most vul-
nerable stage a certain number may be killed by either the lime-sul-
phur or soda-sulphur solutions; but neither of these sprays can be
recommended for the whitefly.
In view of the fact that sulphur in almost any form is a specific
against mites, it is found to be advantageous at times to combine it
with emulsions or miscible oils in one spraying. This has been
the practice of some growers for years. Thus, flowers of sulphur
has been added to whale-oil soap with apparently satisfactory results
for insects and mites. Others have added the soda-sulphur to
whale-oil soap solution before applying it to the trees.
To further demonstrate the mixing qualities of flowers of sul-
phur, soda-sulphur, potash-sulphur (liver of sulphur) and lime-
sulphur. a series of tests was conducted. Whale-oil soap, kerosene
emulsion. Other's Formula IV, Schnarrs' Insecticide, Target
Brand, and Scalecide were tested. It was found that lime-sulphur
will not mix with any of these without injury to the mixture. The
lime-sulphur serves as a hardening agent of the water. With the
oil-containing mixtures, oil would rise to the surface; in the soap,
a precipitate was formed which, however, remained mixed in a finely
divided state so long as the soap was in excess, and such a mixture
could undoubtedly be used for spraying, care being exercised that
sufficient soap is present. The soda-sulphur and the liver of sul-
phur mixed well with all of the insecticides mentioned, except that
after an hour some kerosene began to rise to the surface with the
kerosene emulsion. Flowers of sulphur mixed readily with whale-
oil soap. With the emulsions and miscible oils the flowers of sul-
phur formed a thick scum, apparently a mixture of sulphur and
emulsion, which settled in part to the bottom and in part rose to the
surface. The formation of this scum was obviated by first treating
the water employed with whale-oil soap, using one to three pounds
per fifty gallons of water, or sufficient to soften the water. By
thoroughly incorporating the flowers of sulphur with this before
adding the insecticide, no scum was formed. It is best to make a
Annual Report, 1911
paste of the dry sulphur before adding it to the mixture of soap
and water or other spraying solution. In this paste the small lumps
can be readily broken up. Dry sulphur does not readily mix with
water, but when a small amount of soap is added to the water it
wets the sulphur and a plaster is formed. In all cases where sulphur
is employed in a spraying mixture it is necessary to keep the mixture
continually agitated to keep the sulphur from settling.
EGGS OF WIIITEFLY AND SPRAYING MIXTURES.-A series of
tests was made to determine the effect of spraying mixtures, es-
pecially of Black Leaf 40, upon the eggs of Aleyrodes citri. (Black
Leaf 40 is a concentrated tobacco extract, guaranteed by the Ken-
tucky Tobacco Product Co., Louisville, Ky., under the Insecticide
Act of 1910, to contain 40 per cent. nicotine sulphate.) The excel-
lent results obtained by C. P. Gillette, of the Colorado Station (Jour-
nal of Economic Entomology, Vol. 3, No. 2, April, 1910) upon
aphis eggs prompted this work. The figures in the following tables
indicate probably not so much the effect of the insecticides upon the
eggs, as upon the ability of the young larvae to attach themselves or
to develop. Further experiments need to be conducted with the
mixtures, and careful microscopical examinations need to be made
to determine the percentage of eggs that actually fail to hatch. It
is not intended that final conclusions should be drawn from these
tests, but some of the results are definite. It appears that there may
be insecticides which will give definite results when aplied to the
eggs of the whitefly. This is important, since instead bf" having to
wait ten days or two weeks for the eggs to hatch, spraying could
begin as soon as the adults have quit swarming.
The upper figures of each double row are from tests made under
the supervision of the writer on a sour orange tree; the lower figures
are from tests made on Satsuma trees by Mr. Loftin. In each
case, twigs having twelve to fifteen leaves were selected and dipped.
After dipping, each twig was enclosed in a small cheesecloth sack.
Some difficulty was at first experienced because the mixtures would
not completely wet the leaves, especially the youngest ones. By
adding whale-oil soap, at the rate of one or two pounds per 50
gallons of water, this difficulty was obviated.
Good's Potash Whale-oil Soap No. 3 was used. The mixtures
of 2 pounds of soap to 50 gallons of water with Black Leaf 40, may
be regarded as tests for Black Leaf 40, the soap being added in
order that the liquid should wet the leaves.
Black Leaf 40 was found to have the effect upon kerosene
emulsion of causing a separation of kerosene. By dipping the
leaves as soon as the mixture had been prepared this difficulty was
Three to six weeks after dipping and bagging, the leaves w-re
liv Florida Agricultural Experiment Station
INSECTICIDES AND WHrrEFLY EoGs
No. of eggs No. of PIercentage of
Mixture less No. of live live
dead larvae larvae larvae
Whaleoll soap 1 to 6 1628 315 19
(Pounds to gallons) 831 600 83
Whaleoll soap, 2 to 50, and 784 76 10
B.L.40, 1 to 500 1008 1041 103
Whaleol soap, 1 to 6, and 1222 204 17
B.L.40, 1 to 500 468 1016 217
Whaleoll soap, 1 to 6, and 1798 130 7
B.L.40, 1 to 300 482 982 204
Kerosene emulsion i 964 147 15
1 to 15 967 849 86
Kerosene emulsion, 1 to 15, 1656 101 6
and B.L.40. 1 to 500 981 410 42
Kerosene emulslon. 1 to 15,. 1000 66 7
and B.L.40, 1 to 300 762 597 78
Whaleoll soap, 2 to 50, and 1085 221 22
soda sulphur, 1 to 30 1105 1244 112
Whaleoil soap, 2 to 50, and 1865 48 8
soda sulphur, I to 20 453 590 130
Schlarr's, 1910 None 0
1 to 40 1872 44 3
Schnarr's, 1 to 40, with 1-2 None 0
B.L.40, 1 to 500 -2710 19 0.7
Schnarr's 1 to 40, with 1872 None 0
B.L.40, 1 to 300 3254 12 0.4
Others' formula IV, 1623 2 0.1
1 to 50 720 28 4
Others' formula IV, I to 50,! 1089 11 1
and B.L.40, 1 to 500 2253 35 1.5
Others' formula IV, 1 to 50,1 1549 None 0
and B.L.40, 1 to 300 547 18 3
Target, 1 to 50 1583 9 0.6
2367 6 0.3
Target, I to 50, and 1083 14 1
B.L.40, 1 to 500 3415 9 0.3
Target, 1 to 50, and 1280 6 0.5
__ B.L.40, 1 to 300 1979 7 0.4
Scaleclde, 1 to 50 653 2 0.3
1532 84 6
Scalecide, 1 to 50, and 1138 18 2
B.L.40, 1 to 500 2020 None 0
Scaleclde, 1 to 50. and 435 24 2
B.L.40. 1 to 300 940 None 0
On orange 1872 1350 98
434 615 142 (unbaggod)
On Satsuma 2092 2380 114
540 1825 245
1451 16600 115
removed and the numbers of eggs and eggshells, the numbers of
dead larvae, and the numbers of live larvae counted on each. The
Annual Report, 1911
percentages were obtained by subtracting the number of dead larvae
from the number of eggs and eggshells, and dividing the result into
ioo times the number of live larvae. The same procedure was
followed with the checks. Of course, these results are only roughly
approximate, for it is obvious from the checks that many of the
dead larvae had died from natural causes.
Wherever the percentage given in the tables is greater than
loo, this may indicate that many of the eggshells on the leaves fell
off while in the sacks.
WEIGHT OF WHITEFLY PUPAE
In order to get a more adequate idea of the actual drain upon
the trees, weighing of the nearly mature pupae were made during
March, 1911. The pupae were those of the white-winged species of
the whitefly (A. citri). In all, 3400 pupae were weighed, but only
2400 are included in the table, because the average live weight of
one lot of iooo was afterwards found to be only about half the
average obtained from the other weighing. Precautions were
taken during the process of collecting the pupae to keep them from
drying. As soon as a small lot had been collected this was placed
under a small bell jar. It required about 4 hours to separate a
thousand pupae from the leaves. After the live weights had been
taken, the larvae were dried from five to seven day at 60 C on
a hot water bath, and then weighed again. These weights are
given in the table as "Dry Weights." Each lot of larvae was then
placed in a sulphuric acid dessicator where they remained for about
one month, or until their weight became constant. This weight is
given as the "Dessicated Weight." Accurate chemical weights and
balances were used, and the results are given in the tables to a
tenth of a milligram.
WEIGHTS OF WHITEFLY PUPAE
Number Live Dry Dessicated Water Percentage
Weight Weight Weight Lost Water lost
1000 .0700 .0455 .0419 .0281 40
1000 .0653 .0384 .0372 .0281 43
400* .0274 .0165 .0153 .0121 44
The weighing was done in the chemical laboratory by Prof. Blair and
*200 female pupae and 200 male pupae.
Taking the average of the above figures, 1,000,000ooo pupae would
weigh 67.8 grams or 2.39 ounces avoirdupois. This amount of
whitefly flesh appears to be small, but when coupled with the
Florida Agricultural Experiment Station
amount of honeydew that I,ooo,ooo larvae excrete in a month,
namely 15 pounds (Report x9o8 and Bulletin 97), and remember-
ing that this honeydew contains sugar and other solid matter be.
sides water (Report 1909), we get some idea of the actual drain
upon the trees caused by a million whitefly larvae.
Another set of weighing were made to determine the differ-
ence in weight between the female pupae and the male pupae. The
pupae were well advanced, each having a brick-red spot showing
through the back. The eyes of the adult could also be plainly seen
within. The pupae from trees growing in pots in the greenhouse
weighed slightly less than those from trees in the open. The first
two lots in the following table are the same as the lot of 400 in
the previous table.
WEIGHTS OF MALE AND FEMALE PUPAE
It 200 males 0.0087 g.
In the open..--------- .- females 0.0187 g.
200 males 0.0075 g.
In greeuse.- 200 females 0.0181 g.
TIIE WOOLLY WHITEFLY
On February 11, 191 i1, a brief survey was made of the distribu-
tion of this species (Alcyrodes howardii) in Tampa and Ybor City.
A few to as many as several dozen larvae per leaf were found in
most of the trees examined. The woolly whitefly was found at
the following places: Tampa Bay Hotel, Central Avenue and Har-
rison Street, Kay and Governor Streets, Third and Nebraska Ave-
nues, Oak and Nebraska Avenues, Ninth Street and Nebraska
Avenue, Amelia Avenue and Morgan Street, Michigan Avenue and
Morgan Street, Ola and Michigan Avenues. The trees were more or
less generally out of condition, dusty, full of scales and of the
white-winged whitefly (A. citri). None of the fungus diseases of
whitefly were found; and those of scale insects, although all present,
were apparently not in a thriving condition. At Ybor City the
woolly whitefly was found in the grove of Mr. E. W. Aman, and
in several other places.
During 1909, Dr. E. A. Back, then Field Agent of the Bureau
of Entomology, discovered this species in Tampa and Ybor City.
Previously, it had only been known to exist in Cuba and other
West Indian Islands. Dr. Back first directed attention to it in
the Florida Fruit and Produce News of November 26, 1909, and
later in Bulletin No. 64, Part viii, Bureau of Ent, U. S. Dep. of
Annual Report, ip9r
MIGRATION OF WHITEFLY
Certain observations made by Mr. F. Vans Agnew, in following
the whitefly from Kissimmee across Lake Tohopekaliga to Para-
dise Island may be mentioned here. In August 1910, while a breeze
was blowing southward, and the air was full of adult whiteflies,
Mr. Vans Agnew, fearing that the fly would now reach his grove
on the island, watched them from his boat all the way to the island,
a distance of two miles. The whiteflies were seen swarming in and
about the boat and over the water while fish were snapping up any
that fell in. Whitefly soon developed in his grove. This observa-
tion corroborates the writer's previous statements that the whitefly
spreads principally by this kind of migration from the infested
chinaberry and umbrella trees. These trees are plentiful in towns,
thus endangering the surrounding groves. Neglected citrus and
other food plants also add their quota. The writer had actually
observed the whitefly migrate only about a mile (Bulletin 97, p. 62).
The importance of keeping the whitefly down to its smallest number
in order to check its spreading cannot be emphasized too strongly.
With thorough work in destroying breeding places much can be
accomplished, as has been demonstrated at Winter Haven (Bulle-
tin 103, p. 18) and Arcadia.
RUFOUS ScALE.-(Aspidiotus articulatus Morg.) During a
visit to the grove of Mr. Robert Leach near Largo, a small quantity
of the scale was discovered in a couple of trees. In August j9o9,
Dr. A. W. Morrill discovered this insect at Key West. and gave
a brief account of it in The Florida Grower of February 17, 1911.
TOBACCO DusT.-Four small scale-infested citrus trees in pots
in the greenhouse were given a handful of tobacco dust at inter-
vals of about a month, beginning with February and continuing
through June, 1911. At the end of that time two of the trees
had died, apparently from the effects of scales and mealy bug. No
effect upon the scales or mealy-bug was noticed. The scales were
the Purple Scale (Lepidosaphes beckii) and the Round Scale
(Chrysomphalus aonidium). The mealy bug was Pseudococcus
citri. Hence we may conclude that tobacco dust used as a fertilizer
does not affect the scales on the tree.
E. W. BERGER,
Iviii Florida Agricultural Experiment Station
REPORT OF PLANT PATHOLOGIST
P. H. Rolfs, Director
SIR: I submit herewith the report of the work in Plant Path-
o!ogy for the fiscal year ending June 30, 1911.
The greater part of the time was given to the investigation
ol diseases of citrus trees. The disease known as Stem-End Rot,
which was reported for the first time last year, received most at-
tention, and the investigation of a fungus found to produce gum-
niing when inserted into healthy citrus, peach, and other trees, and
to cause the rotting of fruit, was also carried on. Other diseases
of citrus were under observation and study. This work was great-
ly aided by the assistance of Mr. 0. F. Burger. The investigations
in regard to Scaly Bark of citrus have been brought to a close and
the results were reported in Bulletin io6.
Diseases of other plants received some attention as opportunity
and time was afforded.
This disease was mentioned for the first time in last year's
Report. The information then at hand was that Stem-End Rot
was a serious decay of sound fruit as well as of injured fruit; that
this rot developed often on sound oranges in transit; that it was
caused by a fungus growth which usually entered at the stem end;
that it might be transmitted from diseased oranges to healthy ones
by contact or by soaking them in water; that it might be transmitted
also by means of pure cultures of the fungus placed in water in
which the fruit was soaked; that the fungus could infect the fruit
through a stem at least 3 inches long; that fruits could be infected
by placing them in water with soil from under infected trees; and
that it took from one to three weeks- after infection for symptoms
of the rot to appear.
During the past year much additional knowledge in regard to
the disease has been obtained by observations and spraying experi-
ments in various orange groves in the State, and by experiments
and study in the laboratory.
Further infection experiments in the laboratory showed that
injury to the rind of the fruit, although not a necessary factor in
infection, made the fruit more subject to it, and also shortened the
time required for rotting to appear after inoculation.
Further study in the grove, supplemented by isolation tests in
the laboratory, showed that the spores of the fungus were pro-
duced in abundance on dead twigs and branches of citrus trees and
on rotting fruit on the ground. The fungus was isolated repeatedly
from recently killed twigs. It was also isolated from the inside of
Annual Report, 191z
diseased fruits, while they were still green, as early as the last week
in August of the past year. The disease was found to be widely
distributed in the State. It appears to be present to some extent in
nearly every citrus-growing district in Florida. It seems to be
more destructive on moist hammock soils than in drier situations.
Spraying experiments for the control of this disease were
carried on in four different localities, representing three counties.
Four fungicides were used. Bordeaux mixture (5 pounds of
copper sulphate and 5 pounds of lime to so gallons of water) ; am-
moniacal copper carbonate (3 pints of ammonia and ; ounces of
copper carbonate to 50 gallons of water); copper sulphide spray
(self-boiled lime-sulphur of formulae 8-8-5o, with the addition of
2 pounds of copper sulphate in solution); and commercial lime-sul-
phur, 3o Baume (2 gallons to 5o gallons of water.) Ten trees
were sprayed with each spraying mixture during the first weeks in
October, November, and .December, and ten trees were kept for
checks in each locality.
A monthly record of the number of dropped oranges was kept,
with the percentage of Stem-End Rot. Through the co-operation
of A. V. Stubenrauch and H. J. Ramsey of the Bureau of Plant
Industry, shipping tests of the fruit were made from each plot.
' wo shipments were made, one in December, and one in January
In each shipment, two boxes were shipped from eadh plot. These
were inspected on arrival at Washington, D. C., and at intervals
of one week for four weeks.
The averages of the tabulated records of the entire number of
drops from the sprayed and unsprayed trees, from October to
February, showed that none of the spraying solutions had dimin-
ished the percentage of total drops to any appreciable extent. The
trees sprayed with ammoniacal solution of copper carbonate showed
about the same percentage of drops as the check trees, the Bordeaux-
sprayed trees showed a marked increase in percentage of drops, and
the trees sprayed with commercial lime-sulphur and copper sulphide
showed a slight increase in the percentage of drops. These per-
centages were taken on the basis of the entire number of fruit at
the time the experiment began, obtained by adding the total number
of drops to the number of oranges picked.
In the shipping experiments of fruit from these sprayed and
unsprayed trees made by Mr. Ramsey of the Bureau of Plant In-
dustry, the tabulated records show that the fruits shipped from
the trees sprayed with commercial lime-sulphur were the only ones
that had on an average, less Stem-End decay than the unsprayed
trees. The fruit from the trees sprayed with ammoniacal copper
carbonate showed the same average percentage of Stem-End decay
as the unsprayed trees. The fruit from the Bordeaux-sprayed trees
L.< . Florida Agricultural Experiment Station
showed a greatly increased average Stem-End decay. The fruit
from the trees sprayed with copper sulphide showed a slightly
increased percentage of Stem-End decay.
Experiments in disinfection of the fruit were carried on in
co-operation with the Bureau of Plant Industry, in two packing
houses. Different lots of fruit were treated as follows: First,
sprayed with ammoniacal solution of copper carbonate, (a) as the
fruit cam~e out of the wash-water, (b) after being soaked in water
v. ith pieces of decayed fruit for 20 minutes, (c) after being soaked
in water with cultures of the fungus for 20 minutes. Second,
sprayed with potassium sulphide, i ounce to 2 gallons of water, after
being soaked in water with decayed fruits for 20 minutes. Third,
soaked in part of same water in which decayed fruit had been
placed, after treating it with copper sulphate at the rate of I
pc und to iooo gallons. Fourth, soaked in part of same water after
treating it with formalin at the rate of 12 pints to 1ooo gallons of
water. Check lots were kept consisting of (a) fruit washed only,
(b) fruit soaked in water with decayed fruit for 20 minutes with-
out spraying, and (c) fruit soaked in water with cultures for 20
minutes without spraying. Two boxes of each lot in each of the
two packing houses were used. These were set aside and inspected
every two weeks for six weeks. The tabulated records of Stem-
End decay did not indicate that there was any beneficial result from
aiy of the treatments. In general, there was a slightly greater per-
centage of Stem-End decay in those boxes that had been disinfected
than in those kept for checks, and there was considerably more
blue mold decay in the disinfected than in those not treated.
A more detailed account of this work is being prepared for Bul-
letin 107 of this Station.
BLACK ROT (Alternaria citri Pierce)
A rotting of oranges which begins at the "blossom" or stylar
end, was observed in one locality in the State. The blackening ex-
tended through the central rag including the core. Cultures were
made from the interior of a number of fruits, and a fungus, which
appears to be Alternaria citri, was isolated. This fungus was de-
scribed by N. B. Pierce (Bot. Gaz. xxxiii, No. 3, pp. 234, 238. 1902).
It causes a serious disease of navel oranges in California and Ari-
zona. J. E. Coit, in Bulletin 58 of the Arizona Experiment Sta-
*ion, says as to treatment: "All diseased fruits should be carefully
gathered up and either burned or buried." It was found in Florida
attacking the Blood and Pineapple varieties of the sweet orange.
Annual Report, i9ir
BLUE MOLD ROT (Penicillium italicui \ Wehmer and Penicillium
This most common kind of rotting can scarcely be called a dis-
ease, but is included here because of the decay resulting from the
action of these fungi. As far as known, these blue mold fungi are
only able to enter fruit after it is injured in some way. A slight
scratch or bruise is sufficient to allow the fungus to make an en-
trance provided there is sufficient moisture and heat. 'lhe two
most common species of blue mold fungi on citrus fruits in Florida
are Penicillium. italicum and P. digitatum. Specimens of these two
fungi were kindly identified by Dr. Charles Thom of the Storrs Ag-
ricultural Experiment Station, Connecticut.
Penicillium italicum is recognized by the blue green color, and
P. digitatum by the olive color of the affected areas. The latter,
according to Dr. Thorn, is the same as P. olivaceum. Wehmer.
DIPLODIA ROT (Diplodia natalensis Evans)
A decay of citrus fruits, which in its early stages is quite simi-
lar to Stem-End rot, has been found during the past year to be due
to a fungus which is probably Diplodia natalensis Evans. (Science
Bull. No. 4, Transvaal Department of Agriculture.) The decay
usually begins at the stem end in the same manner as does the Stem-
End rot described in our last report. It may be distinguished, how-
ever, at a later stage by dark bands extending from the stalk to the
blossom end corresponding to the division walls between the sec-
tions of the fruit. This decay is usually more rapid and extends
more quickly through the middle of the blossom end of the fruit
than does the Stem-End rot. It also causes the fruit to turn black
and lose rapidly in weight as the decay proceeds.
DIPLODIA NATALENSIS AS A GUM-INDUCING AND FRUIT-RoTTING
A species of Diplodia has been found by Mr. 0. F. Burger and
myself during the past year growing within recently killed tissue
of gumming peach and citrus branches. This fungus was isolated
in pure cultures, and by inoculation has been shown to produce copi-
ous gumming on healthy individuals of these hosts, and also to
produce rapid decay of citrus and other common fruits when placed
in contact with them.
It was first obtained from the interior of gumming peach
branches by 0. F. Burger in July of last year, and was afterwards
isolated by him from gumming peach branches from five different
counties of the State. In September of the same year, a fungus
Florida Agricultural Experiment Station
was isolated from gumming orange and grapefruit limbs, and was
afterwards obtained from ten localities in six different counties of
the State. It was also isolated from partially decayed citrus fruits,
both oranges and grapefruit. These cultures were readily ob-
tained by cutting out a piece of wood from beneath the bark of a
gumming area after sterilizing the surface with a flame, and drop-
ping the piece into sterilized dilute prune juice, or by cutting out a
small piece from the interior of a partially decayed fruit with a
flamed scalpel, and dropping it into the prune juice, which could be
subsequently plated out in the usual way to obtain pure cultures.
Eleven series of inoculations, covering a period of eight months,
have been made on peach and orange trees; five series by intro-
ducing pure cultures from the peach into peach trees; three series
by introducing pure cultures isolated from citrus into citrus trees;
and three series of cross inoculations, two by introducing the fun-
gus isolated from the peach into citrus trees, and one by introducing
the fungus isolated from citrus into peach trees. The peach trees
used for these inoculations were about two years old, and the citrus
M- W- -___
Fig. 7.-On left; orange tree inoculated with Diplodia at A. Gum oozing above
wrapping. On right; check tree cut at B. Wrapping removed.
Annual Report, g191
trees one to three years old. They were growing in pots in the
One other series of inoculations was made by introducing the
Diplodia isolated from the peach into the trunk and branches of
larger orange trees outside the greenhouse and also into a number
of different wild trees in the woods on the Experiment Station
Fig. 8.-A, orange tree cut, but not Inoculated. B, orange tree inoculated with
Diplodia. C, peach tree inoculated with the same fungus."
In most of the inoculations the bark was cut thoroughly with
a sharp scalpel, a bit of fungus mycelium, or a minute mass of
spores from a culture was inserted, and the inoculated portion
wrapped in paraffined paper and tied with raffia. Check trees, cut
and wrapped in the same way, but not inoculated, were kept for
comparison in every case. Those peach and orange trees into which
Florida Agricultural Experiment Station
the mycelia or spores of Diplodia were introduced gummed more
or less copiously, while those which had been cut in the same way,
but with no fungus inserted, healed up without gumming. In no
case have any of the trees been entirely killed as yet, but in one
instance the cambium on one side of a peach tree in the greenhouse
was killed to a distance of seven and one-half inches from the in-
oculated point, and pycnidia of Diplodia were produced along the
deadened area sixteen days after inoculation. On the peach trees
the gum oozed out in tough, irregular masses 3/2 to Y of an inch
across, and remained attached, not only at the point of inoculation,
but at other places on the bark where it had pushed through cracks.
The gum from the orange was more watery than that of the peach,
but it also in time hardened into large tear-like drops and ridges
below the point of inoculation.
The larger orange trees outside also gummed copiously on the
introduction of the fungus into cuts in the bark. The following
native trees were also inoculated, check cuts being made on each
Wild plum i I'runus umbellataf)
Wild cherry (Prunus serotixaf)
Hickory (Hficoria. sp.)
Cherry laurel (La urocerasus caroliniana)
Pricklddy ash (Xantho.rylum americanum)
Sumach (Rhus glabraf)
Basswood (Tilia pubescens)
Red-bud (Cercis canadensis)
Sweet gum (Liquidamnbar styraciflua)
Hackberry (Celtis georgiana)
Mulberry (Morus, sp.)
Ironwood (Ostrya virginiana?)
Water oak (Quercus, sp.)
Hawthorn (Crataegus, sp.)
Magnolia (M. foetida)
Holly (llex opaca)
Ash (Fraxinus, sp.)
Huckleberry (Vaccinium, sp.)
Of these the following six species produced gum with killing
of the tissue (in each case the corresponding checks showed no
gum and healed up in the regular way): wild plum, wild cherry,
cherry laurel, prickly ash, sweet gum and sumach. The following
four species showed bleeding with killing of tissue but no gum
(the corresponding checks did not bleed nor show any killed tissue
beyond the cut made on the bark) : basswood, red-bud, hackberry.
Two showed slight killing of tissue without bleeding: ironwood
and water oak. The other six-hawthorn, hickory, magnolia,
holly, ash and huckleberry-were apparently not affected by intro-
duction of the fungus. In one inoculation into a limb Y2 inch in
Annual Report, gi9z
diameter, on a wild plum tree, a strip of tissue 5 inches below and
6 inches above the point of inoculation was killed in two weeks,
and in four weeks all leaves above the point of inoculation had
dried up, and gum was exuding at the fork of the branch 5 inches
below. A check cut on the other branches of the fork was healing
up without gumming or killing of tissue (Fig. 9).
Fig. 9.-Wild plum
(Frunus umbellataf) inoculated with Diplodia at (a);
cut, but not inoculated, at (b).
SCAB OR VERRUCOSIS (Cladosporium citri Massee.) This dis-
ease has caused much damage during the past two years in the
southern localities of the State. Formerly it appeared to be con-
fined much more exclusively to sour oranges, lemons, and Satsumas.
It appears that in recent years the fungus is adapting itself to the
grapefruit which before was more resistant to its attacks. Sweet
oranges are nearly immune from the attack of the fungus.
Florida Agricultural Experiment Station
This fungus was received during the year from H. V. S. Peeke,
Fukuoka, South Japan, through Dr. H. G. Keppel of the Uni-
versity of Florida. It is possible that the disease was originally
introduced into this country on Asiatic varieties of citrus.
\VITIERTIp (Colletotrichum gloeosporioides Penz.) This dis-
ease as judged from the reports has been much more destructive this
year in many localities than for some years past. Many groves have
suffered severely from it. The attack of the fungus manifests itself
in a number of different ways at different- seasons of the year. The
following are particularly noticeable: (I) Killing back of twigs
and branches; (2) dropping of bloom and recently set fruit; (3)
browning of tender leaves; (4) brown spotting of older leaves; (5)
brown spotting of fruit, called Anthracnose; (6) tear staining and
russeting of fruit. The first is probably the most serious to the
tree itself. This manifestation of the disease has been successfully
controlled in hundreds of acres by severe pruning out
of (lead and diseased limbs, cutting back into healthy wood in such
a manner as to leave no projecting stubs. Spraying alone has been
Without profit for this phase of the disease. For manifestations
2, 3, 4, 5, and 6 as noted above however, Bordeaux mixture or
ammoniacal copper carbonate have proven effective.
A study of the peach diseases occurring in the State was made
by Mr. 0. F. Burger, Laboratory Assistant in Plant Pathology.
The following diseases were studied:
Root Rot (Clitocybe parasitica).
Crown Gall (Pseudomonas tiumefaciens).
Rust (Puccinia prunispinosac).
Frosty Mildew (Cercosporella pcrsica).
Scab (Cladosporium carpophilumn).
Brown Rot (Sclerotinia fructigena).
Fly-speck fungus (Leptothyrium pomi).
Peach Diehack (Valsa leucostoma)
Gumming (Diplodia natalensis Evans).
Yellows and Rosette?
THE BROWN FUNGUS OF THE CITRUS WIIITEFLY (Acgerita
webberi).-This fungus, which was named and described in last
year's report, is one of the important fungus parasites of the white-
fly in Florida. Specimens of this same species of fungus, collected
at Saharanpur, India, were received during the past year from Mr.
R. S. Woglum of the Bureau of Entomology. In regard to this
fungus Mr. Woglum wrote under date of November 4, 1910:
Annual Report, rp91 lxvii
"The fungus is doing splendid work here in many citrus trees, its
efficiency being most apparent on trees in protected situations where
an atmosphere of dampness is longest retained."
The finding of Acgerita w'ebberi in India indicates that the
fungus came to this country on importations of citrus from the
H. S. FAWCETT,
Florida Agricultural Experiment Station
REPORT OF PLANT PHYSIOLOGIST
P. H. Rolfs, Director
SIR: I herewith submit the report of the Plant Physiologist
for the year ending June 30o, 1911.
PROBLEMS IN CITRUS NUTRITION
The work in the Laboratory of Plant Physiology consists of a
study of the nutrition and the malnutrition of the citrus plant.
Studies in plant nutrition may be made from two standpoints:
first, a chemical study of the raw materials after they have been
absorbed by the plant, and the changes they undergo during the
construction of the food products and the assimilation of these;
and, second, a study of the changes in the tissues and cells of the
plant resulting from various methods of feeding under different
conditions. The latter method has for the most part been employed
thus far in these studies in nutrition. It constitutes a phase of
GREENHOUSE WORK.-It is planned to grow the plants in the
greenhouse where the growth factors can be controlled. Keeping
these conditions as uniform as possible, it is proposed to feed the
plants wth complete and incomplete fertilizers in maximum and
minimum amounts. The plants will be fed uniformly, and the
growth conditions will be varied. A study is to be made of the
gross and minute structures of the plants under these different con-
Conforming to the above plan, experiments are now under way
in the greenhouse to determine the effect upon the citrus plant of
nitrate of soda, acid phosphate, and high-grade sulphate of potash,
when used as fertilizers.
Some of the citrus diseases that are presumed to be due to
malnutrition are Dieback, Melanose, Yellow Spotting, and French-
ing. An experimental study is being made of Dieback. Several
factors are known that will aggravate this disease under field con-
ditions. Two of these factors are; feeding with organic nitroge-
nous fertilizers, and unfavorable soil conditions (such as lack of
drainage, or too compact subsoil). Since the symptoms are the
same under all the different conditions, it is presumed that there
is a common cause for the disease. It is planned to produce the
disease in the greenhouse, and then to analyze the factors which
determine its occurrence.
Experiments are now under way in the greenhouse, where some
plants are being fed with organic nitrogenous fertilizers, and others
Annual Report, 111zz
are being subjected to lack of drainage. One series of plants that
has been fertilized with stable manure since October 1908, shows
symptoms of the disease. Some plants in another series that were
fertilized with cottonseed meal in April, 1910, and again in April,
1911, showed the first characteristic symptoms in May, 1911.
Other experiments having a bearing on different phases of the
disease are also under way.
LABORATORY WORK.-This is intended to go hand in hand with
the greenhouse work. As the experiments being carried on in the
greenhouse develop, a thorough microscopical study is to be made
of the plants, to determine what variations in structure are due
to different treatments.
Thus far, microscopical studies have been confined mainly to
diseased and healthy tissues of plants grown under field conditions.
Such a study has been made of the diseases Dieback and Me-
No extensive chemical studies have been carried out. Such
work as has been done has been confined to the enzymes and gums.
Other minor experiments have been carried out to develop
methods of work.
FIELD EXPERIMENTS.-Much observational work has been done
in different citrus groves in the State. The purpose of this work
was to study the diseases due to malnutrition andohe conditions
under which they occur in the grove, in order to repeat tbse in the
The trees in the experimental grow at Tavares (Fla. Agr. Exp.
Sta. Report, 1909, pp. xxvi-xxx) have become affected with
Dieback since being planted out. Studies are being made of the
disease as it occurs here in its relation to the differently fertilized
STUDIES IN MAXIMUM FERTILIZATION
In studying the effects of maximal* and submaximal amounts
of nitrogenous fertilizers upon the citrus tree under greenhouse
conditions during the year 1909-10, it was found that a spotting
of the leaves occurred which was often accompanied by a fall of
the leaf-blades. The blades in falling left the winged petioles at-
tached to the tree. It was concluded that this leaf-spotting was
caused by a disturbed assimilation due to the absorption of large
amounts of nitrates, which destroyed the balance between nitrogen
and phosphorus within the plant. (Fla. Agr. Exp. Sta.. Report
1910, pp. lxvi-lxx.)
*The term maximum, as here used, is intended to mean theet amouat
of fertilizer that can be used without killing the plant.
Florida Agricultural Experiment Station -
Since the leaf-spotting and fall of the leaf-blades were charac-
teristic of maximum fertilization with a nitrogenous fertilizer under
greenhouse conditions, it is important to know if they are a guide
to similar fertilization under field conditions.
During the year 191o-i I, a grove was found where these symp-
toms had been produced by a maximum fertilization with nitrate
GROVE CONDITIONs.-This grove is located in the central part
of the State, on high pine land. It is composed of grapefruit and
orange trees. The trees were rebudded after the freeze of 1895,
and are of large size. The grove is cultivated with an Acme har-
row, which is used only when it is necessary to conserve the moist-
FERTILIZATION.-The grove was fertilized with a mixture of
500 lbs. of nitrate of potash, 1276 lbs. of acid phosphate, and 224
lbs. of low-grade sulphate of potash. Twenty pounds of this mix-
ture were given to each tree. (Some Satsuma trees in the grove
were given a larger amount.) The fertilizer was broadcasted
around the trees about May 29, 1911. On May 30, a heavy rain
fell, amounting to lb wecn one and two inches. No rain fell for
several weeks after this. and the soil gradually dried out.
SYMpTros.-Early in June, a falling of the leaf-blades and
fruit occurred and continued from day to day, until the ground
under the trees was covered with leaf-blades and much fruit had
The blades that fell were those of the old leaves; the growth
of the current year was not affected. The majority of the leaves
that fell showed brownish discolorations along the midrib and
veins, at the tips and along the margins, or in rounded spots be-
tween the veins. Where the discoloration was along the midrib
and veins, the whole base of the blade was often discolored. The
remainder of the leaf-blade was normal to yellowish green in color.
The Satsuma trees showed a greater leaf-fall than did the other
trees. This was because more of the fertilizer had been given to
The fruits that fell were almost entirely culls. They were
stunted or badly marked by melanose or scab, or weakened in
some other way. Upon falling, many of the fruits became dark
brown to black in patches that sometimes covered the whole fruit.
these patches were sunken, but there was no softening of the fruit.
The discoloration varied as to the depth to which it extended into
the fruit. Where the whole surface was discolored, the discolor-
ation usually extended entirely through the fruit
Globules of gum could frequently be seen on the surface of the
Annual Report, 1911
blackened areas. In some cases, on cutting the fruit open, gum
pockets were found in the rind and in the angles of the segments.
Sometimes the surface discoloration could be traced inward to the
gum pockets, and in other cases it could not.
Specimens of these fruits were referred to H. S. Fawcett, the
Plant Pathologist of this State, for examination for fungi. Cul-
tures failed to show the presence of the fungus that causes Stem-
End Rot, or of any other fungus that is known to make fruit fall.
A quantity of the fruit brought into the laboratory and allowed to
remain in an open vessel, developed an extensive growth of the
withertip fungus (Colletotrichum gloeosporioides Penz.).
The grapefruit trees in this grove had been divided into five
plots in order to test the effect of sprays upon the development of
Melanose. Two plots were unsprayed; three plots were sprayed
with (j) self-boiled lime-sulphur solution, (2) three-quarters
strength and (3) full strength ammoniacal solution of cpper
carbonate, respectively. The sprays were applied in April about
two weeks after the petals had fallen.
The fruit-fall shows a decided relation to the spraying of the
plots. Observation of the plots showed that the amount of fruit
that fell was much greater from the trees of the unsprayed plots
than from those of the sprayed plots. The arnouit that fell from
the trees sprayed with the self-boiled lime-sulphur solution was
much less than that from the trees sprayed with different strengths
of ammoniacal solution of copper carbonate. The number that fell
from one tree in the check plot was 333; whereas the total number
that fell from two trees in the plot sprayed with lime-sulphur so-
lution was 55. The fruits that fell were mainly culls. The spraying
reduced the number of culls. *
In contrast toL this the fall of the leaf-blades showed no re-
lationship to the plots. The fall was uniform under all the trees.
excepting the Satsuma trees which received a greater amount of
CONCL.usIONs.-Since only the old leaves and only the cull fruit
fell, it is apparent that the chemical injury has shown itself only
in the weaker parts of the trees. The injury is neither a severe one
nor a permanent cne, since the new growth is not visibly affected.
The symptoms indicate that a maximum amount of nitrate of
potash has been used. Had a greater amount been applied under
the given conditions, a permanent injury would probably have re-
The symptoms of this case of chemical injury under field con-
ditions agree with those of nitrate injury as obtained under green-
Florida Agricultural Experiment Station
house conditions, and establish the value of these symptoms as an
index to such injury in the grove.
DIRBACK IN CITRUS EXPERIMENTAL GRovE.-In January,
1909, a citrus experiment was started on Lake Harris near Tavares,
Lake County, Florida, in co-operation with Mr. G. M. Wakelin.
(Fla. Agr. Exp. Sta. Report, 1909, p. xxvi.)
The purpose of this experiment was to determine the effect of
certain fertilizers upon the chemical and physical properties of the
soil, upon the trees, and upon the quality and quantity of the fruit;
and to study the relation of the fertilizers to the insect pests and
diseases that affect the orange tree.
In July 1910, Mr. Wakelin reported that the trees were gener-
ally affected with Dieback. A close examination showed about
78 per cent. of them to be affected. The disease was in an early
stage, and none of the later symptoms, such as bark exudations,
were to be found. Gum pockets and the characteristic S-shaped
branching were generally distributed; a few multiple buds could be
found; and stained terminal branches were scattered at'intervals. A
few trees bore fruit; and some of these showed the markings known
ab ammoniationn", which are characteristic of the disease.
The appearance of many of the trees was not thrifty. The
growth in the upper part was very slow. This condition showed
no relation to any particular plots. The heaviest growth came
from limbs low on the trees and from suckers. The gum pockets
occurred for the most part in these rank-growing branches. It is
possible that the top growth was stunted by the cold during the
winter of 1909-10.
On March 22-23, 191i, the trees in the grove were again ex-
amined. At this time the new spring growth was complete and
beginning to harden. The major part of the growth was again
from the lower branches of the trees. The amount of new growth
was greater than that of the previous season. On this account the
trees showed a better general appearance.
At this time, 50o per cent. of the trees in the grove showed gum
pockets in the new growth. Further symptoms had appeared in
the growth of 1910; about 86 per cent of the trees showed fresh
symptoms in that year's growth; bark exudations and stained termi-
nal branches were plentiful. In many cases the withertip fungus
attacked these weakened branches, killing them back some distance.
RELATION OF DISEASE TO PLOTS.-The disease appears to be
independent of the fertilizers that have been applied to the different
plots. Plots given organic nitrogenous fertilizers are no worse
affected that those that had other nitrogenous fertilizers; and none
of the fertilizers show any particular inhibiting effect upon the
Annual Report, ipz9
disease. It is possibly too early yet for the fertilizers to show any
beneficial or detrimental effect upon the disease.
At the time of planting the trees, three-quarters of a pound of
steamed bone was given each. This was mixed with the soil in
the hole where the tree was placed, so that it was closely associated
with the roots as they developed. It is possible that this fertilizer,
being in part an organic nitrogenous fertilizer, had to do with the
inducing of the dieback condition in the trees.
Table XXII, shows the number of the trees in each plot that
were affected by the disease at the times the notes were taken.
Column I shows the number that were affected in July, 1910o;
column II shows those in which symptoms of the disease had de-
veloped during the whole growing season of 19io; and column III,
those in which symptoms had developed in the spring growth of
1911, as determined by notes made in March, 1911. The number
of trees that show affection of the new growth in March, 1911, is
no indication of the total development of the disease for the year,
for it does not reach its greatest development until after the sum-
mer rainy season.
The number of trees in each plot is ten. The fertilizer was
applied in February. June. and October of each year, beginning in
June, 1909. The standard formula for the June and February
applications was, ammonia, 5 per cent.; phosphoa acid, 6 per
cent.; and potash. 6 per cent. The standard formu|lr the Octo-
ber application was 2y :6:8. Two pounds of fertilii were given
to each tree.
Melanose is a disease of the citrus tree. It is distributed through
all parts of Florida where citrus is grown. The cause of the disease
has not yet been determined.
Webber and Swingle (Principal Diseases of Citrus Fruits in
Florida: Div. Veg. Phys. and Path. U. S. Dep. Agr.. Bul. 8) report-
ed the disease in 1892 from Ocala, Citra, Stanton, and Sanford.
They concluded that the disease was of recent origin at that time,
and that it was contagious. However they failed to find any organ-
ism that was causing it. They employed a treatment with Bor-
deaux mixture or ammoniacal solution of copper carbonate, which
is still our only means of fighting the disease.
Melanose is not confined to Florida. What appears to be the
same disease has been reported from numerous other countries.
In Australia it has proved to be as injurious as in Florida. The
disease reported from there is identical in gross and microscopic
appearance and in habit with the Florida disease. But Cobb (Agri-
Plot Different amounts I II in
1 Half the standard -- --- ------------ 4 8 6
2 Standard --------------- 2 4 8
3 Double the standard-- 6 9 5
4 Four times the standard--------------------- 9 8 7
5 Phosphoric acid and ammonia Increased by one-half---..... 9 8 4
( Phosphoric acid and potash Increased by one-half-----.. 8 9 5
7 Ammonia and potash increased by one-half-------........--- 10 8 5
8 Phosphoric acid and potash decreased by one-half---.. 9 10 6
9 Phosphoric acid and ammonia decreased by one-half--- 9 10 7
10 Ammonia and potash decreased by one-half-.------- 9 7 2
11 Standard and finely ground limestone -------.--- 7 10 5
12 Standard and air-slacked lime------------------------ 9 9 6
13 Standard and mulch ---- --------- 7 7 2
14 Standard ----------------------------------- 8 10 a
Nitrogen from different sources
15 From nitrate of soda----------------------------- 9 7
16 Half from nitrate of soda, and half from sulphate of I
ammonia ------------------------------------ 9 9 a
17 From dried blood -------------------------------- 8 8 8
18 Half from sulphate of ammonia, and half from dried
blood --------------------------------------- 9 8 4
19 Half from nitrate of soda, and half from dried blood_- 7 7 3
20 From cottonseed meaL....--------------------------- 4 4 0
21 From cottonseed meal. (With ground limestone. --- 6 5 3
22 Half from cottonseed meal, and half from sulphate of
ammoniat --.--- ----------- ..----- 8 9 2
23 Half from cottonseed meal, and half from nitrate of soda 10 9 5
I'/l, sph,'ric acid from different sources
24 From dissolved lone black ----------------------- 7 10 7
25 From samed tine ----------------------------- 10 9 4
26 From steamed Iimo. i Double amount. ----------- 9 10 9
27 From Thonas' sing. i Nitrogen from nitrate of sodn. i- 8 8 4
28 From Thomas' slag. (Double amount. Nitrogen from
nitrate of soda- ----- --------------------------- 4 6 4
29 From ncild phosphate. (Potash, 7 1-2 per cent. In June,
7 1-2 per cent. in October and 3 per cent. In ib. .-- 8 7 1
30 From niild phosphate. (Nitrogen from nitrate -of soan.
Potash from hardwood ashes) ------------------- 4 4 3
31 From acid phosphate. (Standard.) ----------------- 10 10 7
32 From dissolved boneblack ....--------. ----- ---- 8 9 9
33 From floats --------------------------------- 10 10 8
34 From floats. (Double amount.) -------------------- 9 10 6
35 From floats. (Four times amount.) ----------------- 9 10 4
36 From floats. (Four times amount. Nitrogen from
cottonseed meal) --..............------------............--------------.. 8 10 1
Potash from different sources
87 From low-grade sulphate........................---------------. 9 9 5
88 From muriate-------------- ------...............------- ... 9 8
39 From high-grade sulphate. (With ground limestone.) 10 10 7
40 From kailt ....---------..........------.....--------------------......... 10 a
41 From high-grade sulphate. (Standard.) --------- 7 9 7
42 From nitrate of potash. (Balance of nitrogen from
nitrate of soda.)..--- -------..... .........- 8 9 6
Different culture, etc.
48 No fertilizer ---- ...------- --...........------- 3 4 0
44 Standard ---.. ...... ... 7 10 8
45 Standard and mulch...... .....8 8 4
46 Standard and clean culture- .........--- 10 10 10
47 Nitrogen from dried blood. Clean culture....... 9 10 9
48 Nitrogen from nitrate of soda. Clean eilture.--- 7 68
Total number of trees affected with dle .......---- 373 411 1241
Annual Report, 1911
cultural Gazette of New South Wales, vii, 4, pp. 225-228) and Mc-
Alpine (Fungus Diseases of Citrus Trees in Australia and their
Treatment, Department of Agriculture. Victoria, 1899) have con-
cluded that it is due to a fungus, which the latter has named Clad-
osporium brun,,o-atruim. They were able to distinguish this fungus
easily upon the margins of the diseased spots. On the other hand,
Single and Webber could find microscopical evidence of fungal
hyphae in the Florida disease only occasionally; and they were
never able to obtain the fungus in culture. Wehber has suggested
Fig. io.-Advanced st'j elanose.
that the disease in the two countries is caused by the same fungus,
but that in Florida it exists only in its vegetative stage.
Melanose is reported also from l-'orto Rico. Jamaica, and Al-
HABITS OF THE DISEASE.-Melanose affects nearly all varieties
cf citrus fruits that are grown in Florida. None have been found
that are particularly immune. This is in contrast with the disease
Florida Agricultural Experiment Station
as it exists in Australia, where McAlpine reports that it affects
only the sweet orange.
Leaves, stems, and fruits are affected by the disease. These are
susceptible only while they are in a young succulent condition; and
immediately their tissues begin to mature, they become immune.
The markings remain upon the leaves and fruit throughout their
life, but those upon the stems remain only until the true bark is
formed, after which they are sloughed off. For this reason, the
symptoms of the disease are never found on the trunk, or on stems
more than two years old.
EFFECT UPON THE TREE.-From a practical standpoint, the
greatest injury done by the disease is to the fruit. If the markings
are plentiful, the fruit is likely to be stunted and weakened. Under
adverse growth conditions, these fruits will be amongst the first to
Fig. i.-Melanose W ruit. Rows of spots. (Magnified.)
fall. If the fruit develops to maturity with the markings, it may not
be of the best quality, and its unsightliness will reduce its market
The effect of melanose upon the leaves and stems is to reduce
their working ability, by closing up the breathing pores and disturb-
ing the normal cellular activity in these regions. Quite frequently
these parts are stunted, and in some cases killed.
Annual Report, i9r
GROSS APPEARANCE OF MELANOSE.-The symptoms of melan-
ose are nearly the same in gross appearance upon the leaves, the
stems and the fruits. They consist of surface markings that vary
considerably in outline and size. Some are small, rounded, coni-
cal or dome-shaped spots that range from mere points to one-
sixteenth of an inch in diameter. (Fig. I I.) These may be accom-
panied by variously sized areas that are irregular in outline and
appear as though made up by a number of small confluent spots.
When the spots and areas are young, the epidermis of the affected
tissue is unbroken. (Fig. 12.) Upon maturity the epidermis some-
times breaks in a line following the margins of the spots; and the
surface of the areas becomes split in lines like dried mud.
For the most part, these spots and areas have a very irregular
distribution over the affected part. Sometimes, they arrange them-
selves in lines forming circles or arcs of circles. Again, they may
bc arranged on the fruit so as to give a tear-stained appearance
which resembles that produced by the withertip fungus.
The markings in their matured condition are more or less raised
above the surrounding surface. On the fruit they usually show
less elevation than on other parts. They may or may not be accom-
panied by a yellowing of the adjacent tissue.
They have a wax-like appearance, and vary fr yellow to
brown or black. They are frequently spoken of as bling little
drops or masses of partly burned sugar.
MICRoscoPic STRUCTURE.-There is little variation in the struc-
ture of the markings as they occur on the leaves, stems, and fruits.
Fig. 12.-Section of Melanose spot, with unbroken epidermis.
lxxviii Florida Agricultural Experiment Station
In each case the spots and areas.are raised by the development of a
phellogen which produces a layer of cork tissue that separates
the affected tissue from the healthy tissue below. (Fig. 12.) In
the leaf, this phellogen usually takes its origin in the epidermis.
Where it occurs near the upper surface, the extent of its develop-
ment is indicated by the amount of tissue between the crystal cells
and the epidermis. In the stem. it originates sub-epidermally.
(Figs. 12 and 13.)
The affected tissue rarely extends to a greater depth than five
or six cells. These cells are soon filled with a homogeneous gum-like
substance that is easily stained with safranin, methylene blue, and
acid fuchsin. This substance is probably a mixed gum. It is in-
soluble in water, and is not removed in the processes of killing,
washing, and embedding. It is apparently a product of the proto-
plasm. collected in the vacuole. The cell walls remain intact. Be-
fore the discoloration produced by the collection of the material in
the cells becomes too great, the nucleus can still be seen, and is
apparently in an active condition. In later stages the protoplasm is
The phelllerir cells are arranged in columns. (Fig. 13.) It
Fig. 13.-Section of Melanese spot on stem, showing phelloderm cells in columns.
Annual Report, 19t1
is the growth of these cells that raises the surface of the affected
spots. Many of these cells contain a hollow spherical body in their
protoplasmic mass. (Fig. 14.) These sometimes occur crushed in,
forming a double walled hemisphere. The nature of these spheres
was not determined.
Fig. 14.-Phelloderm cells.
tMagnified over 15oo diameters.)
Particles of fungal hyphae can sometimes be distinguished
in the affected tissue. These may or may not be those of saprophytic
RELATION TO GROWTH FacTORS.-The occurrence of Melanose
has no direct relation to either soil, moisture, or food. Trees planted
on high pine-land and on hammock land are equally affected; those
en dry soils are affected as much as those on wet soils; and the dis-
ease is as prevalent in well-fed groves as in neglected ones.
But the disease does have a direct relation to temperature, and
to the presence of disease and of dead wood in the trees. In the
central part of the State, new growth that started in the trees in
January 1911, was noted to be entirely free from the disease. Low
temperature conditions prevailed during the developmental period of
this growth. But the succulent growth present in the trees in April,
1911, when higher temperature conditions prevailed, was affected.
The same relationship was noted in the autumn. New growth
starting before the first period of cold was affected; whereas that
starting after this period was not affected.
The disease has been noticed to be worse in the growing seasons
following severe winters. The older growers in the State report
it to have been very injurious the year following the freeze of 1895.
Florida Agricultural Experiment Station
It was more prevalent in the northern portion of the citrus belt in
the spring following the cold winter of 19o9-1o. Apparently, the
general effect of the cold upon the tree is to make it more susceptible
to the disease.
The disease also has a relationship to the presence of dead wood
in the tree. Fruit so located that water from dead wood will drop
upon it, often has a tear-stained arrangement of the disease mark-
ings. It has been noticed that where Melanose was associated with
much dead wood in the tree, pruning was helpful in reducing the
disease. If the disease is caused by some plant organism, it is
possible that the dead wood serves as a source of infection.
Diseased and weakened trees are susceptible to Melanose. It is
nearly always to be found upon trees affected with Blight, Scaly
Bark, Yellow Spotting, and other diseases.
COMPARISON WITH OTHER DISEAsEs.-Melanose has some
points in common with other citrus diseases. Its resemblance to the
citrus scab, which is caused by Cladosporium citri Massee, is most
striking. The markings caused by these two diseases are somewhat
similar in structure and in distribution. The scab does not have the
brownish deposits in the affected cells that characterize Melanose.
The gum-like deposits in the affected cells of Melanose are simi-
lar to those of the stained terminal branches of Dieback; but the lat-
ter are seldom raised, and are never accompanied by the develop-
ment of a phellogen.
A phellogen is sometimes developed in Yellow Spotting of citrus;
late stages of the spots caused by this disease resemble melanose
areas in gross appearance. But the general structure of the diseased
areas in Yellow Spotting characterizes it as a malady wholly differ-
ent from Melanose.
CONCLUSION.-From the facts known, it seems probable that
Melanose is not caused by unfavorable growth factors; but that it
is a disease which is due to some unknown organism. The following
facts seem to point to this conclusion.
I. The symptoms are superficial, and seldom extend farther
than five or six cell-layers into the plant.
2. The size, distribution, and individuality of the markings.
3. The development of a phellogen in the tissue of the affected
spot or area.
4. The similarity of the above characters to those of citrus
scab, which is known to be due to the attack of an organism.
5. Inhibition by low temperature.
6. Association with dead wood in the tree.
Annual Report, 1911
7. Ready response to the use of the copper fungicides. (These
may also be beneficial on account of their stimulating effect upon the
This organism may be either a plant or some minute animal. If
it is a fungus, it probably exists only in a vegetative condition, and
its hyphac are diminutive, making it difficult to distinguish in the
Judging by the descriptions given by Cobb and McAlpine (1. c.)
of the melanose that occurs in Australia, it is identical with the mel-
anose that we find in Florida. McAlpine concludes that the dis-
ease is due to a fungus. However, since he reports no inoculation
experiments, it is to be inferred that he came to this conclusion from
finding the fungus associated with the diseased spots on the host
plant. The superficial character of the disease allows the affected
tissue to be easily attacked by saprophytic fungi immediately it is
dead. From this fact, it is possible that the fungus described by
McAlpine is saprophytic. Hence. it is to be concluded that the
cause of Melanose is as yet unknown.
B. F. FLOYD,
Florida Agricultural Experiment Station
REPORT OF ASSISTANT BOTANIST
P. H. Rolfs, Director
SIR: The following is the report of the Assistant Botanist for
the year 1910o-1.
SECOND GENERATION OF THE CROSS BETWEEN VELVET AND LYoN
OBJECT.-The primary object of this breeding experiment was
to study, quantitatively, the inheritance of the different characters in
the first two or more generations of the cross between Velvet and
Lyon beans; and, in addition, to isolate a smooth-podded race of
beans which would not scatter their seeds. Several such beans ap-
peared in the second generation from the cross; and also, unexpect-
edly, some beans which were earlier in flowering and ran less to
vine than either the Lyon or the Velvet. A remarkable result was
the production of pods and beans that were considerably larger than
those of the Lyon bean, as well as others that were distinctly smaller
than those of the Velvet bean. (The characters of the first [Hy-
brid] generation were given in the Report for last year.)
PLANTS OP THE SECOND GENERATION.-An acre field was lined
into 8-foot squares, and 625 beans were planted in order at the
angles. All these beans (except 75 at 3 sides) had been previously
measured. (They came from the hybrid plants of 7 hills.) The
beans from each pod were put into a separate envelope, marked with
'the number of the parent plant(hill), the letter of the pod, and the
number of the stake in the field. Each bean was numbered in se-
quence from the stylar end of the pod. In this way the bean from
which each plant grew was known.
On July 25-27, notes were taken on every plant; and again on
October i1-13. All the vines were cut down by early frosts from
October 31 to November 2. The pods were then harvested sepa-
rately from each plant in large paper sacks. On an adjacent acre,
seeds of the parent strains of Velvet and Lyon beans were sown;
together with more than half an acre of hybrid beans, four feet
apart and two seeds to the hill. (These latter were treated in the
usual commercial way for isolating novelties, but no further men-
tion of them will be made in this Report.)
YOUNG SHooTs.-The ends of the shoots, including the young-
est leaves, were closely covered with hairs; which were either white
o' yellowish, mixed dark and light, or dark and nearly black. The
dark color was due to blackish contorted hairs like those on the pod
of the Velvet bean. Plants with these dark tomentulose shoots could
be distinguished in the field with fair accuracy from those plants
Annual Report, Ip9
which had a certain amount of this dark "velvety" hair mixed with
the ordinary stiff light hair (as do often the shoots of the Velvet
bean itself). Out of 43 early plants (flowering before July 25)
only 4 had dark shoots, and these four also bore pods with similar
dark pubescence. Out of the 44 late plants (not in flower by Octo-
ber 25), 31 had dark hairs on the shoots. Out of the total number
(317) of plants observed for this character, 61 had quite dark
shoots, and 256 had either mixed dark and light pubescence, or
light-colored shoots. Of the 61 plants with dark shoots, 42 pro-
duced no pods, 17 yielded pods with more or less dark "velvety"
hair, and two were noted as producing pods with stinging hairs.
Were it not for this last observation, it might be asserted that black
"velvety" shoots bore dark "velvety" pods (but not vice versa). It
is probable that the hairs on the young shoots and leaves owe their
consistency and color to at least two factors.
Out of the total of 6I plants with dark shoots, 56 were noted as
having distinctly small smooth convex leaflets, which give a peculiar
character to the whole plant. Out of the 34 plants that had:more or
less black "velvety" pods, 15 were noted as having black shots, and
i i of these bore nearly smooth pods.
FORMS OF LEAVES.-The leaves were classified in the field on 285
plants. (The leaves of the remaining 33 plants had withered before
this.) Out of these, 83 plants had undulate blades like the Lyon;
62 plants had leaflets between plane and undulate; 84 plants were
noted as having plane leaflets like the velvet; and 56 plants had
smooth convex leaves and black shoots. The limits of the second
and third of these classes were sometimes doubtful. t
SIzEs oF PLANTS AND TIMES OF FLOWERING.-On July 25-27,
the growing plants were classified as to size into five grades. The
43 early flowering plants fell into the five classes in the numbers 1,
5, 21. iS, i; average, 3.23. The 44 plants which never flowered
before frost arranged themselves in the classes according to the num-
bers o, 12, 19, i1, 2: average, 3.o7. Thus the earliness and lateness
respectively were not apparently due to any earliness or lateness in
starting growth, but were probably genetic.
FLOWERs.-The flowers were either purple or white (wings and
standard). No intermediates were noted in the field, and the stand-
ard was never (in purple flowers) quite as white as it is sometimes
in some velvet beans. There were 135 purple to 41 white, out of 176
plants whose flower colors were noted. This is in the ratio 3 to I,
within the mean error. From the absence of intermediate grades,
we may conclude that the purple color of the flower is determined
by one factor which is absent in the Lyon bean. Coupling of pur-
ple flower color with the purple underside of the first simple leaves
and with the purple spots on the leaf-axils seems probable, but was
not further studied.
Florida Agricultural Experiment Station
HAIRS ON PoDs.-These are of four main kinds. First, the long
stiff easily-detached irritating hairs like those of the first (Hybrid)
generation, or "stinging" hairs. Second, the short stiff hairs like
those on the Lyon bean, or "downy" hairs. Third, the long weak
twisted blackish hairs like the majority of hairs on the velvet bean
pod: "long velvet," or simply "velvet." Fourth, the short dark
twisted hairs which are often so thinly scattered that the pods are
nearly glabrous: "short velvet" or "smooth." A few of the pods
have hairs intermediate in length between stinging and downy.
The stinging hairs may be yellow or brown, and the pod may
be striped with longitudinal lines of reddish-brown hairs. The
downy hairs may be yellow or white. Some of the stinging
pods bear also a little velvety hair. The velvet often contains
long, stiff. white or yellow hairs, or many short, stiff, downy
hairs. There are also grades between velvet and smooth. Spec-
imens of the hairs from pods of all the plants were mounted
as microscopical objects. Ten of the longest hairs on each slide
were measured, and the average taken. Accurate measurements
could not be made of the twisted cottony hairs of the velvet and
"smooth"; but the former were usually between one and one and
a half mm., and the latter one-half mm. or less.
S EGREGATES: m
*,L, n. ,. N.._..._. N .
If J 4 77 f Jys j '07 S 47f rf'
Fig. 15.--Variation curve of the measurements of length of the stiff pod
hairs of those plants of the Segregate generation which bore ripe pods. Classes
of five micrometer divisions each,. one division being o.o0124 mm.
Out of 189 plants with full-grown pods and stiff hairs, 151 had
the longest hairs on the pods in classes between 1.33 and 1.71 mm.,
3 had hairs in classes between 0.96 and I.o9 mm.; and 35 had hairs
in classes between 0.59 and 0.78 mm. (Compare Figs. 15 and 17.)
These 35 were regarded as downy pods. the i51 were classed as
Annual Report, ig9ii
stinging. The length of the pod hairs of a parent Lyon plant
(L.152), grown in the same field, was 0.67 nmm.; and the length of
the pod hairs on the Hybrid (grown in 1910), was 1.58 mm. In-
cluding plants which produced only a few small pods, there were in
all 163 plants classed as possessing long stinging hairs on their pods,
4o with short downy hairs (five of these being intermediate), 22 with
long dark velvety hairs, and 12 with more or less smooth pods and
short dark velvet. Of these, 20 stinging, 9 downy, 14 velvet, and
9 smooth, set no ripe seed before frost. In percentages of the total
numbers, these late-ripening plants whose pods were caught by frost
were: stinging, 12; downy, 23; velvet, 64; and smooth, 75. Thus
there was a larger proportion of very late plants among the downy,
and a much larger among the velvet and smooth, than among the
stinging. It would thus appear that the presence of dark tomentum
on the pods is usually (but not always) correlated with late flower-
ing and ripening. The plants which have dark velvet hairs on the
young leaves and shoots usually have also short or long dark velvet
hairs on the pods. Out of 8o plants which did not produce any pods
before being cut down by frost, 42 had dark velvet hairs on the
shoots. It is highly probable therefore that the numerical propor-
tion of plants producing velvet and smooth pods was too low, on ac-
count of the lateness of ripening of many plants with this kind of
pubescence on their pods. (The stinging hairs on the short pods
were only about o.o6 mm. shorter, on the average, than those on
the long pods.)
SEGREGATES: ,'" L,,0:l'
/ 1 -' 7 \
*S7* S. a'.y
I *'I "-- V"" "
V V *- %,
Fig. 16.-Variation curve of the averages of the measurements of the
lengths of five-seeded pods from those plants which bore 2 to 51 such pods.
The outer curve (dotted) refers to the 189 plants which bore i to 51 five-seeded
pods. The curves of plants of the parent strains of Velvet and Lyon, in the
same field, are also shown. Three-millimeter classes. (Numbers of five-seeded
pods measured: Segregates, 1414; Lyon, 443; Velvet, 350.)
lxxxvi Florida Agricultural Experiment Station
*v~ -- _______ -'' A *
Fig. 17.-Pods of eight plants, showing differences in pod length and pod
No. 145.: long stinging hairs; average pod length, to6 mm.: average seed length,
No. 50o: long stinging hairs; av. pod length, 61 mm.; av. seed length, 11.2 mm.
No. 85: short stiff (downy) hairs; av. pod length, to6 mm.; av. seed length,
No. Ic: short stiff (downy) hairs; av. pod length, 59 mm.; av. seed length,
11.8 mm. (white seeds)
No. 464: long dark velvety hairs; av. pod length, 1o0 mm.; av. seed length,
No. it: long dark velvety hairs; av. pod length, 81 mm.; av. seed length, t12
No. 437: black and nearly smooth; av. pod length, io8 mm.; av. seed length,
No. 35o: black and nearly smooth; av. pod length, abt. 56 mm.; av. seed length,
abt. 13 mm.
Annual Report, 1911
LENGTHS OF PoDs.-Only five-seeded pods were measured. The
average lengths of the pods of the different plants varied between
50.5 and I15.5 mm. Taking the 136 plants which bore from two
to fifty-one pods with five seeds, and arranging their average pod-
lengths in classes, the curve shows an obvious division at 75-78 mm.
This is still apparent even if we include the 53 plants of which only
one five-seeded pod was available for measuring. (Compare Figs.
16 and 17.) The ratio in the first case is o105 long to 31 short. This
Fig. 18.-Showing live-st-ecled piIds f plaints of Segregates, larger than Lyon
and smaller than Velvet.
No. -07; average pod length. I 5 nmm. Ivelvety)
Lyon: average pod length. 92 nmm. (downy)
Velvet; average pod length, 63 ninm. (velvety)
No. 5h; average pod length. 55 mm. (downy)
Ixxxviii Florida Agricultural Experiment Station
is 3:1, within the limits of mean error. The longest pods were
longer than those of the Lyon bean, and the shortest pods were
below the length of the Velvet bean. (Compare Fig. 18.) Inves-
tigation of the next generation is needed to analyze this, and to show
whether the plants with the longest and shortest pods are homozy-
gous in this respect or not.
The correlation between the average lengths of the five-seeded
pods, and the average lengths of the seeds of the same plants (in-
cluding only those plants of which 50o to 2oo normal seeds were
available for measuring), for 118 plants, was o.87, with a mean
error of o.o2. But as the pods were obviously in two groups of
shorter and longer, this figure is too large (Pearson). The pods
above 75 mm. gave a correlation of 0.67, with a mean error of o.o6;
while the pods below 75 mm. gave a correlation of 0.51, with a mean
error of o.15.
When the average length of the five-seeded pods was divided by
tne average length of a seed (for the 118 plants of which 50-2oo
normal seeds were measured), it was clearly evident (compare Fig.
19) that the seeds were relatively closer together in the short than
in the long pods.
In the 95 plants with long pods (and more than 50o measured
seeds) the average length of pod (five-seeded) divided by the av-
erage length of seed was 6.1. For 1o hills of the Lyon bean of the
parent strain this average was 6.2. In the 23 plants with short pods
(and more than 50 measured seeds) the average of pod-length di-
vided by seed-length was 5.26. For 1 i parent Velvet bean hills this
average was 3.24.
M4 '2 ". a--*' 8f \
Fig. ig.-Curve of the average lengths of five-seeded pods divided by the
average lengths of their seeds, for the 118 plants from which 50o to 2oo seeds
could be measured. Classes are fifths.
Among the 25 lowest variates in the figure there were 20 (out
vof a total of 23 short-podded) with short pods (less than 75 mm.).
Annual Report, 1911
Hence there was on the average (with some distinct exceptions) a
crowding of the seeds in the short-podded plants, just as there is in
the Velvet bean as compared with the Lyon (Fig. 19). In some of
the short-podded Segregates all the seeds were much flattened where
they were in contact, and in some of the long-podded the seeds were
unusually widely spaced.
,..u-h /Q'z,,7 o-7'76.".M3
/ \ He-avy: i..OS
Fig. 20.-Curve of the average weights of the five-seeded hulls of those i37
plants which had from 2 to 42 such hulls. Quarter-gram classes.
SEGREGATES: s a
Q 1S'55L1-4 -= -'. -30
So at it s a 1 -6 SO 4 *2 a t o 74. 7; P $ 86 9Do 9A -0 /0o
Fig. 21.-Curve of the average weights of the seeds (first three in pod only)
of 115 plants of which 50 to 200 good seeds were weighed, reckoned as per-
centages of the average weights of their five-seeded hulls. Classes of 4 per cent.
WEIGHTS OF HuLLs.-The weights of the dry hulls of the five-
seeded pods depend partly on the thickness of their walls. In some
cases long pods have thin-walled hulls. The average weights of the
five-seeded hulls of 137 plants (average of from 2 to 42 pods for
each plant) gave about 32 of low weight to o105 of greater weight.
(Compare Fig. 20.) This depends chiefly on the actual length of
the pods. When the average weights of the seeds were taken as
percentages of the average weights of the five-seeded hulls (for the
115 plants from which 2 to 42 pods and o50 to 200 normal seeds were
weighed), the classification and curve (Fig. 21) showed that the
short pods usually, but not invariably, gave a larger figure than the
Florida Agricultural Experiment Station
longer pods. Of the 14 highest values, zo were of short and 4 of
OPENING OF PoDs.-The number of pods which opened and
scattered their seeds varied on individual plants from o to nearly all
of the pods. Out of 117 plants that had from 50 to 2oo seeds fit
for measuring, 30 had no pods open after some months, and the
number of open pods on the rest varied from I to 11 6. Fifty-five
had from one to six open pods, 27 from 6 to 30, and only 5 more
than 30 open pods. There is, obviously, a segregation of this char-
acter, even if the data do not permit of any hypothesis as to the
number of factors concerned. Of the 30 plants which had no open
pods, 3 bore short pods, and 27, long pods. The average number of
open pods for ii parent Velvet bean hills in the same field (exam-
ined five to six months after harvesting), was 1.2, 7 out of the ii
plants having no open pods. The average number of open pods
fur 9 Lyon bean hills of the parent strain was 73, varying from 34
to 228 per plant.
NUMBERS OF BEANs.-The average number of beans in the pods
varied remarkably in the different plants of the second generation;
while in the parent strain of Lyon and Velvet grown in the same
field the mode wa- in both cases 4.12. Some of the large
"smooth" pods, especially, usually had only one seed in the pod;
while other plants with stinging pods had often the unusually high
number of seven perfect seeds. (In almost all cases the pod adapted
its growth to fit the number of seeds.) Taking the 85 plants from
Fig. 22.--Curve of average number of seeds in pods of those 85 plants in
which from 50 to 237 healthy pods were opened. (The same minimum is
found in the curve of the 41 plants with only 25 to so50 healthy pods.) Classes
Annual Report, z1911
each of which the seeds of 50 to 237 pods were counted, the averages
vary between 1.5 and 5.25 (compare Fig. 22), with a minimum at
the mode common to the Lyon and the Velvet. (The 41 plants of
which only 25 to 5o pods were opened show a zero class at 4.12.)
TOTAL CRor.-The total crop varied remarkably. Only ripe
seeds were weighed, the unripe seeds and the hulls being discarded.
Qut of the 316 plants (two of the total of 318 being-injured when
small), 44 were late and produced no flowers before they were cut
down by frost. Out of the 43 plants which flowered early (July 23
lo 27), 6 bore no crop of healthy beans, and the crop produced by the
rest varied from a few grams to over a kilogram. Out of the 229
plants which flowered between July 27 and October 13, 85 bore no
crop of seeds, 39 bore less than 50o grams of healthy seeds, and the
crop of the rest varied from 5o grams to over a kilogram. Most
of the 85 bore no crop because of late flowering. But it appears
that a small total crop of beans was sometimes due to genetic fac-
tors apart from late flowering. For many of the plants had finished
setting pods, and their leaves had died down before the first frost.
Among these were some that yielded heavily. The crops from ii
hills of parent Velvet beans grown in the same field varied from
200 to 700 grams of healthy seeds; while those of the hills of the
parent Lyon strain varied from ioo to 900 grams. There must of
course be many factors concerned in the production of the total
crop; for the majority of the characters of the embryo, seedling, aind
adult plant are probably more or ess concerned. It seems probable
that in the new collocations of characters in the second or Segregate
generation of such a cross as this, in which the parents doubtless
differ in many factors (and which is presumably a species cross),
there will be cases where characters derived from different parents
do not work harmoniously together for the production of a maxi-
mum crop. Such maladjustments (compare W. J. Spillman, Am.
Breed. Mag. II. No. x, p. 72. 1911) often bring about their natural
and speedy elimination. In the acre field used for this test, 135
plants, or 43 per cent. of all plants, were naturally eliminated in
their first year, because they bore no ripe seeds before frost, though
they all produced vines, and, in some cases, late flowers.
Condition of Crop.-In some plants a large number of seeds
were wrinkled. The Lyon bean rather frequently produced some
wrinkled seeds, but the Velvet bean more rarely. In some cases, the
wrinkling was doubtless due to destruction of the leaves by cater-
Pods of Stizolobiums resting on damp earth are sometimes at-
tacked by fungi (Scierotiuon rolfsii, and Cephalothecium roseum
were identified by the Plant Pathologist, H. S. Fawcett, as the two
commonest). The pods of the different plants differed much in
Florida Agricultural Experiment Station
this respect. Since this depends on the number of pods that were
in contact with the soil and on their early or late ripening, it was
not possible to procure reliable numerical results. It seemed prob-
able that this condition may depend to some extent on the charac-
ter of the plant as well as on the accidents of its surroundings.
Out of thousands of pods examined, only two or three were
found to have been attacked by any insect, in this case, the larva of
DIMENSIONS OF SEEDs. A correlation of the lengths of Velvet-
bean seeds with their positions in the pod, showed that only the
first three seeds, reckoning from the stylar end, were approximately
uniform in decrease of length. Hence, in all these measurements of
seeds, only the first three seeds of a pod were measured. All after
these were rejected-for measuring, weighing, or estimation of mot-
tling. (Though all the seeds answering the conditions up to 15o. on
all plants (however few), were measured, weighed, and graded for
mottling, it was judged best to only reckon with those plants in
which from 50 to 150 (or 200) healthy seeds were available.) By
rejecting all seeds after the third in a pod, the mean error for I5o
seeds was reduced to nearly the same amount as for 300 seeds taken
from all positions in the pod. Thus the Velvet bean, V. o109, had a
mean error of 0.05 in the measurement of the lengths of 150 seeds
(first three in pod), while 293 seeds of a Velvet bean of 1910,
measuring all in the pod, gave a mean error of o.o4. The Lyon
bean plant, L. 157, had a mean error of o.o5 in the measurement of
150 seeds (first three in the pod) ; while 308 seeds of Lyon bean in
1910. including all in the pod, gave the same mean error of 0.05.
To test for biological errors, several plants whose harvested
crop filled two sacks, had 15o or fewer seeds measured independ-
ently from each sack (taking of course only the first three seeds
f om each pod). Thus in the case of plant No. 94, 150 seeds from
one sack gave for the average length, breadth, and thickness, 13.8...
11.7...8.7; while 115 seeds of the same plant from the se.-md
sack gave 15.7... 11.7.. .8.8. Plant No. 120 gave, with 15o beans
from the first sack. 15.6... 10.9.. .7.7; and with 15o beans from the
second sack, 15.4... 10.7.. .7.9. Plant No. 294 gave, with 15o
seeds from one sack, 17.T... 12.1.. .9.5; and with only 33 seeds
from the other sack, 17.o. . 12.1.. .9.5. The Velvet bean, V. 172,
gave, with 200 seeds from one sack, 12.1.. .9.8.. .8.3; and with
150 seeds from the other sack, I1.8. ..9.6...8.2. Lyon bean, L.
157, gave, from the first sack, 15.2... 11.4.. .8.2, and from the sec-
ond sack, 15.3... 11.6. .8.3; 150 seeds being measured in each
case. In picking the beans, the readily visible pods, which are usu-
ally the ripest, are naturally picked first in one of the sacks, and so
the sampling error in this case is larger than usual, and often greater
than the statistical mean error.
Annual Report, 1911 xciii
To find what variations may be expected from plant to plant in
the same pure line, eleven Velvet bean hills were grown side by
side, from seeds which had come from a single seed planted in 1909.
Of each of these, 150 seeds were measured. The Ii average lengths
varied from 12.5 to 11.3; the average breadths from o10.3 to 9.2;
and the average thicknesses from 8.7 to 7.4.... Omitting one plant
which was evidently ill-ripened, the average lengths varied from
12.5 to 11.7; the breadths from 10.3 to 9.7 and the thicknesses from
8.7 to 8.1. Hence the variation in different plants of presumably
the same pure line is greater than in two sacks collected from the
same plant in the field. The variation probably due to "modifica-
tion" (compare Erwin Baur, Vererbungslehre, p. 6) is, in these
Velvet beans, greater than that due to bad sampling. It appears
therefore that in calculating the dimensions of the seeds from one
plant it will be usually sufficient to give the final result to the first
place of decimals.
LENGTHS OF BEANs.-The average lengths of the seeds of the
118 plants from which 50 to 150 seeds were measured, varied be-
tween o10.55 and 2o.o5 mm. When arranged in classes, the curve
showed a distinct minimum at 13.3 mm. (Compare Fig. 23.)
n ires irr i*s m/ \
Fig. 23.-Curve of average lengths of seeds of those x18 plants of which 50
to 2oo seeds were measured. (The broken line shows all plants (181) with any
measured seeds.) Half-millimeter classes. (Numbers of seeds measured: Seg-
regates, 14722; Lyon, 190o; Velvet, 1700oo.)
There were about 27 plants with lower averages, and 91 with high-
er averages. Hence the ratio is probably 3 :I. If all the 181 plants
which had any seeds at all worth measuring are classified as to
their averages, the resulting curve resembles that of the above i18
plants (compare the broken line in Fig. 23) ; but the unripeness of
most of these seeds is obvious from the excess in the lower classes.
Florida Agricultural Experiment Station
The factors for the the length of the seed doubtless segregate, and
the seed-length is correlated with the length of the pod. There are
Fig. 24.-Showing seeds of Segregates longer than Lyon and shorter than
No. 437: average length of seed, 19.4 mm.
Lyon: average length of seed, 15.2 mm.
Velvet: average length of seed, 11.9 mm.
5b: average length of seed, 9.9 mm.
many Segregate plants which have seeds of greater length than
those of the parent Lyon strain grown in the same field in the same
season, and some which have shorter seeds than the parent Velvet.
(Compare Fig. 24.) The average of the lengths of the seeds of
the xI parent Velvet bean hills was 11.9, the average of the 27 Seg-
regate plants with shorter seeds was 12.1. The average of the o10
Annual Report, z191
parent hills of Lyon bean plants was 15.2, and the average of the
91 Segregate plants with longer seeds was 15.6. The largest seeds
were found in plants with smooth or velvet pods, and the smallest
ifn plants with downy pods.
No. 58; average seed-ngth, 2
No. 85; average seed-length, 17-14 In=
No. 437; average seed-lengt" 19.37 mm.-
Fig. 25.-Vshowsthetransgressivevariation curves of the lengths of i5o seeds (fm first three in
pods) from four plants of the Segregates, and from one plant each of the
parent Lyon and Velvet strains. Showing traon the samgressive individual variation.
No. x58; average seed-length, firs11.02 three in each pod.m.
V. 171; average seed-length, breaths of mm.
No. bi4; average seed-length 13.7 in classes, theremm.
L. 157: average seed-length, small5.8 and large as in the.
No. 85; average seed-length, the division7.14 at .
No. 437; average seed-length, 19.37 ram.
Fig. 25 shows the transgressive variation of the lengths of the
seeds of four of the Segregate plants and one plant each of the
parent Lyon and VelveFig. 26) it rains grown on the same ground. Of
each, 15o seeds were measured, and only the first three in each pod.
BRmo ADTHS OF BEAtheir.-The average breadths of the seeds of
the 118 plants from which from 5o to i5o seeds were measured,
varied between 8.3 and 13.55 mm. When arranged in classes, there
was not such a distinct division between small and large as in the
cases of lengths of pod and of seed. If we take the division at 1o.I
rum., we have about the ratio 86:32. When the curves for the av-
e-age widths of the parent Velvet and Lyon beans are plotted on
the figure (compare Fig. 26) it is seen that they are beyond the
modes of their respective segments of the curve. The seeds of the
second generation of beans are on the whole narrower than they
would be if the breadth of the Lyon were inherited as a dominant
xcvi Florida Agricultural Experiment Station
MNaow: t SEGREGATES: us
M ". o ". -W 8"$
Fig. 26. Curve of averages of breadths of seeds of those 118 plants of
which 50o to 200 seeds were measured. (The broken line shows all plants with
measured seeds.) Quarter-millimeter classes.
over the narrowness of the Velvet bean and independently of the
length. (This is more strikingly shown if we reckon for each plant
the average breadth as a percentage of the average length. The re-
sulting curve for 18 plants, shown in Fig. 27, has a mode far below
that of the parent Lyon beans grown under the same conditions.)
!'he average breadth for the 32 narrowest seeds was 9.6, the average
for the Ix Velvet-bean plants was 9.9; the average breadth for the
86 plants with longer seeds was 11. and for the io Lyon parents,
11.5. The correlation between the average lengths and breadths of
the seeds of the 11 8 plants gave o.87 as the correlation figure, with
a mean error of o.o2. Hence the breadths of the seeds of the Lyon
and the Velvet do not segregate distinctly, independently of the
Fig. 27. Curve of average breadths of seeds as percentages of average
lengths of seeds, for zi8 plants. Classes of two per cent.
Annual Report, 1911
lengths, in the second generation of their cross. But the shorter
beans are broader, and the longer beans narrower than would be the
case if the breadth were proportional to the length. (Fig. 27.)
For the average seed widths as percentages of the seed-lengths, we
have for the short seeds, 79.4; and for the long seeds, 70.I. The
Velvet bean gives 83.0, and the Lyon, 75.6. The average breadth
of the seeds of all the 118 plants is 10.7 (mean error, o.i) ; the
average of Lyon and Velvet parent strains being also 10.7.
There are no plants on the correlation table showing anywhere
near the absolute breadth of the Lyon with the length of the Velvet.
If breadth segregates independently of the length, as apparently oz-
curred in the homozygotes of a cross between two pure lines of
beans made by Johannsen (Erblichkeitslehre, p. 421), it is so ob-
scured by the double relation to seed-length as not to be readily dis-
cernible in the second generation.
M/ M=&Z-'06 0--7 4'=-
of fifths of a millimeter. (Broken line includes all plants with measured seeds.)
THICKNESSES OF SEEDs.-The average thicknesses of the seeds
of the 118 plants varied between 6.3 and 9.7 mm. (Compare Fig.
28.) The averages of the crops of the parent Lyon and Velvet
strains were 7.9 and 8.3. There is no distinct evidence of segre-
gation independent of the length. The coefficient of correlation be-
tween length and thickness was 0.40 with the mean error of o.o8.
This low figure may be partly due to the different degrees of ripe-
ress, which seem to affect the thickness more than they do the
length or breadth. The averages of the seed thicknesses of the 26
plants with thinner seeds was 7.3, and of the 92 with thicker seeds,
For the average seed-thickness as percentage of the seed-length,
we have for the short seeds, 65.o, and for the long seeds, 53-5. The
Velvet bean gave 69.8, and the Lyon, 52.0.
Florida Agricultural Experiment Station
WEIGHTS OF SEEDS.-Given the length, breadth, and thickness
of a seed, the weight presumably follows, for the specific gravities
of the seeds of Velvet and Lyon are nearly the same. But, of these
three characters, length of seed is correlated with length of pod,
and with breadth of seed, and to a less degree with thickness of
seed. The size of the seed-coat determines the shape and the size,
and consequently the weight of the seed. Hence the weight of a
seed may be taken as a convenient measure of its volume, and reck-
coned as a maternal characteristic. The average weights of the
seeds of the 118 plants with more than o50 weighed seeds varied be-
I M-ItW*2. cr*^ --
*S3 .* *77 *89f ie 1yS eW 19e 7 o ft e3 Iss
Fig. go. Curve of average weights of seeds (first 3 in pods) of 118 plants
with ;o t.- 2oo measured seeds. (Broken line shows curve for the 182 plants
with any weighed seeds, and obviously includes many unripe ones.) Classes
of six centigrams.
* M-j 7. 'it ,r-.iq
Fig. 30o.--Curve of average amounts of surface covered by mottling in the
i t8 plants with o0 to 2oo or more good seeds, and (broken line) in the 185
plants whose seeds (even if few) could be used for estimation of mottling.
(This outer curve is not trustworthy since the mottling often varies on dif-
ferent racemes of the same plant.) Classes in half-ninths. (Zero mottling
in separate class.)
Annual Reporl, pJ i
tween 0.5 andl 1.9 g. The curve (compare Fig. 29) has a dis-
tinct mininumn at 8.3 g., with a ratio of about 87:31.
MoTTi.lIG OF SEEDS.-For the averages of 118 plants, where
5C to 15o (or 200) seeds were measured,. the amount of mottling
varied from o to 8.5 ninths.
Out of these there were
only two plants which had
all their seeds without one
fleck of mottling.
Omlitting these two, for every
ninth from 0.5 to 8.5 ninths,
the numbers were 8, 6, I2,
pare Fig. 30.) The average
mottling of II plants of the
parent Velvet strain was 3.7.
"? The apparent ratio of mot-
tied to white, 116:2, is 63:1,
^ ^ within thle limits of the mean
error. \Ve may perhaps make
1 P66 the temporary hypothesis that
there are three independent
factors for the mottling, each
of which produces some mot-
S~tling even when heterozygous
and in the absence of the two
others. In many of the plants
30- the amount of mottling is af-
fected in different parts of
stances. In these cases the
beans of one pod almost in-
variably have the same degree
S of mottling, and,. with a -few
~ exceptions, this is usually the
Ftg case with all pods on one ra-
ceme. But in such plants.
the seeds on different racemes
Fig ..t Sample weeds of ten of tile differ remarkably in the de-
S.gregatt'>i; t liomw degrees of iharp gree of mottling. Some ra-
iottliitng (otn the 'lft), and of spread
nittling (on tlhe right o. In tile ca.,e of cenmes may bear only pure
the two lowest seeds this distinction was white beans, for example, and
drawn froni i few inore heavily bottledd others strongly mottled ones.
sotde nl the tam plant. mol oe
seeds i tithe .lllne anIIts. The degree of mottling in
these cases diepentds so inuch oil external circumstances that one can