November, 1928
UNIVERSITY OF FLORIDA
AGRICULTURAL EXPERIMENT STATION
Wilmon Newell, Director
VARIETY TESTS OF WHITE
POTATOES
By L. 0. GRATZ
Bulletins will be sent free upon application to the
Agricultural Experiment Station
GAINESVILLE, FLORIDA
Bulletin 201
BOARD OF CONTROL
P. K. YONGE, Chairman, Pensacola
E. W. LANE, Jacksonville
A. H. BLENDING, Leesburg
W. B. DAVIS, Perry
E. L. WARTMANN, Citra
J. T. DIAMOND, Secretary, Talla-
hassee.
J. G. KELLUM, Auditor, Tallahassee
STATION EXECUTIVE STAFF
WILMON NEWELL, D. Sc., Director IDA KEELING CRESAP, Librarian
S. T. FLEMING, A. B., Asst. to Di- RUBY NEWHALL, Secretary
rector K. H. GRAHAM, Business Manager
J. FRANCIS COOPER, B. S. A., Editor RACHEL MCQUARRIE, Accountant
ERNEST G. MOORE, M. S., Asst. Ed
MAIN STATION-DEPARTMENTS AND INVESTIGATORS
AGRONOMY
W. E. STOKES, M. S. Agronomist
W. A. LEUKEL, Ph. D., Asso.
C. R. ENLOW, M. S. A., Asst.*
FRED H. HULL, M. S. A., Asst.
J. H. WALLACE, Asst.
ANIMAL HUSBANDRY
A. L. SHEALY, D.V.M., Veterinarian,
in Charge
D. A. SANDERS, D.V.M., Asst. Vet.
E. F. THOMAS, D. V. M., Lab. Asst.
F. X. BRENNEIS, B. S. A., Asst.
Dairy Investigations
CHEMISTRY
R. W. RUPRECHT, Ph.D., Chemist
R. M. BARNETTE, Ph. D., Asst.
C. E. BELL, M. S., Asst.
H. L. MARSHALL, M. S., Asst.
J. M. COLEMAN, B. S., Asst.
J. B. HESTER, B. S., Asst.
COTTON INVESTIGATIONS
W. A. CARVER, Ph. D., Asst.
M. N. WALKER, Ph. D., Asst.
E. F. GROSSMAN, M. A., Asst.
RAYMOND CROWN, B.S.A., Field Asst.
ECONOMICS, AGRICULTURAL
C. V. NOBLE, Ph. D., Ag. Economist
BRUCE McKINLEY, B. S. A., Asst.
M. A. BROKER, M. S. A., Asst.
R. H. HOWARD, B.S.A., Field Asst.
ECONOMICS, HOME
OUIDA DAVIS ABBOTT, Ph. D.. Chief
L. W. GADDUM, Ph. D., Asst.
C. F. AHMANN, Ph. D., Asst.
ENTOMOLOGY
J. R. WATSON, A. M., Entomologist
A. N. TISSOT, M. S., Asst.
H. E. BRATLEY, M. S. A., Asst.
HORTICULTURE
A. F. CAMP, Ph. D., Horticulturist
M. R. ENSIGN, M. S., Asst.
HAROLD MOWRY, Asst.
G. H. BLACKMON, M. S. A., Pecan
Culturist
PLANT PATHOLOGY
G. F. WEBER, Ph. D., Asso.
K. W. LOUCKS, B. S., Asst.
ERDMAN WEST, B. S., Mycologist
A. H. EDDINS, M. S., Asst.
BRANCH STATION AND FIELD WORKERS
W. B. TISDALE, Ph. D., Plant Pathologist, in charge, Tobacco Experiment
Station (Quincy)
Ross F. WADKINS, M. S., Lab. Asst, in Plant Pathology (Quincy)
JESSE REEVES, Foreman, Tobacco Experiment Station (Quincy)
J. H. JEFFERIES, Superintendent, Citrus Experiment Station (Lake Alfred)
W. A. KUNTZ, A. M., Assistant Plant Pathologist (Lake Alfred)
J. FRANKLIN FUDGE, Ph. D., Assistant Chemist (Lake Alfred)
GEO. E. TEDDER, Foreman, Everglades Experiment Station (Belle Glade)
R. V. ALLISON, Ph. D., Soils Specialist (Belle Glade)
J. L. SEAL, Ph. D., Associate Plant Pathologist (Belle Glade)
L. O. GRATZ, Ph. D., Associate Plant Pathologist (Hastings)
A. N. BROOKS, Ph. D., Associate Plant Pathologist (Plant City)
A. S. RHOADs, Ph. D,, Associate Plant Pathologist (Cocoa)
STACY 0. HAWKINS, M. A., Field Assistant in Plant Pathology (Homestead)
D. G. A. KExBERT, Field Assistant in Plant Pathology (Bradenton)
R. E. NOLEN, M. S. A., Field Assistant in Plant Pathology (Monticello)
FRED W. WALKER, Assistant Entomologist (Monticello)
*In cooperation with U. S. Department of Agriculture.
VARIETY TESTS OF WHITE POTATOES
By L. O. GRATz /1
Much time, energy, and money have been devoted to the
development of seed white potatoes in many parts of the United
States. In view of the progress made everywhere, the question
as to whether or not Florida growers are using the best variety
may well be considered.
The principal variety of white potatoes planted in Florida is
the Spaulding Rose No. 4. Seed stock the past five years has
proved highly satisfactory, with few exceptions. Yet Florida
growers have never had the results of any accurate experimental
comparisons of this variety with others to see which would pro-
duce the largest yields or bring in the most net returns.
If greater dividends can be declared, it is well to know how
these may be obtained. It is for this reason that the compara-
tive testing for yield of several standard varieties was started,
and it is deemed advisable to present now the data obtained
during the five seasons beginning with the year 1924 and end-
ing with the spring of 1928.
EARLY HISTORY OF THE SPAULDING ROSE NO. 4
The question as to why Spaulding potatoes are grown in
Florida is ever recurring, both within and without the state. It
is claimed (1) that this variety is better adapted to our sandy
soils, (2) that it matures more rapidly than other varieties,
(3) that it can endure more severe weather than other varieties,
(4) that it produces a greater abundance of foliage essential to
inhibit weed growth, (5) and that it is preferred by the early
market. These and possibly other reasons have been given, but
usually with definite proof lacking.
Another and probably more accurate explanation for the
growing of the Spaulding Rose No. 4 in Florida may be obtained
from some of the older residents and growers. From them we
learn that the growing of this particular variety is more or less
a matter of custom. In about 1900, long before the seed potato
industry had reached its present magnitude, it was nothing
unusual for the Florida growers to obtain very low yields from
the seed stock planted. Barnyard manure was the only form
of fertilizer applied, and this was used very sparingly because
of the small amount available.
Florida Agricultural Experiment Station
The seed potatoes were obtained chiefly through commission
firms in Jacksonville. These firms bought the potatoes, as such,
and had them classified in their own bins into varieties before
shipping them out for planting. It is obvious that this method
of obtaining seed stock left much to be desired. Instead of ob-
taining a good quality of Early Rose, which variety the growers
probably specified, they may have received a nondescript group
of tubers containing a mixture of Early Rose, Chili Red, Bliss
Triumphs, and other potatoes of a similar color. All that the
growers knew was that they were obtaining potatoes having
more or less the right color. Every other variety which may
have been specified probably came from the same bins or bags.
It was the duty, at that time, of S. T. Spaulding of Avoca,
New York, to sort the potatoes into varieties for one of the com-
mission firms which was supplying potatoes for planting. Mr.
Spaulding saw his opportunity and returned to his home state
with the hope of remedying this unsatisfactory situation in the
South. Sometime later he returned to Florida with part of his
baggage consisting of a number of small samples of potatoes,
which were apparently the progeny of a few tubers selected by
him the previous season. These he planted in a plot near
Hastings and observed them closely throughout the season. The
particular lot which excelled in yield and general appearance
came from Rose tubers planted in row four of the trial plot. This
is apparently the origin of the Spaulding or Spaulding's Rose
No. 4.
The further propagation of this stock cannot be carefully
traced, but it must have been carried on by Mr. Spaulding and
others, first in New York, and of late. in Maine until it has
reached the important place it now occupies. These' original
tubers, selected as they were, apparently possessed more vigor,
or were less diseased, than all other lots planted in the Hastings
section, and in this way became the foundation stock for the
entire potato industry of Florida.
THE VARIETY TESTS
Realizing that a comparison of other varieties, in yield, with
the Spaulding Rose No. 4 would be desirable, an experiment with
this end in view was started with the 1924 crop. Test plots were
planted in representative sections, such as Elkton, Hastings,
Federal Point, and in the Everglades at the Everglades Experi-
Bulletin 201, Variety Tests of White Potatoes
ment Station. Similar results have been obtained from all of
them.
The tests have now been running for five years. However,
five years of trial should not terminate the experiment. To have
any value whatsoever, such investigations must be continuous
through consecutive seasons and be repeated frequently in each
trial plot.
Although it is realized that the experiment should not be con-
sidered final, it is believed advisable to present the preliminary
results for the first five years at this time. In presenting these
data, the intention is not to condemn the Spaulding Rose No. 4,
but to state the facts as obtained by experiment, and to permit
the industry to judge accordingly.
In planning these experiments the yield reduction by disease
was constantly borne in mind and only lots of the different varie-
ties which were as disease-free as possible were obtained and
compared. In general, less disease was evident in the Spauldings
than in some of the other varieties. In no samples was disease,
severe enough to cause an appreciable reduction in yield except
in 1924 when some very poor lots were obtained which were
much below the average in quality. The rows in each compari-
son were from 50 to 200 feet long, depending on the nature of
the plot of ground. The different varieties were either paired
directly with the Spauldings in adjoining rows, or if not paired
directly were never over four or five rows distant from the
Spauldings with which they were compared. Different sample
lots were used each year in these other varieties in order to ob-
tain more representative comparisons between the particular
variety tested and the Spaulding sample with which it was com-
pared.
Table I gives the results obtained for the different varieties
with the numbers of plots and replications involved as well as
the calculated odds. Odds are obtained by the application of
mathematical formulas to the data, for the purpose of deter-
mining the significance of the results obtained. Results with
odds of approximately 30:1 or over are considered significant
while those with odds less than 30:1 are considered not signifi-
cant. The low odds, even with high percentage increases for the
different comparisons in 1924, and several other instances, are
due to an insufficient number of comparative replications. A
larger number of replications were used during the succeeding
trials as will be noted in the figures presented.
'305
TABLE I.-YIELDS IN BARRELS PER ACRE OF DIFFERENT VARIETIES OF POTATOES PLANTED DURING 1924-1928.
Percentage
Varieties Increase Over Calculated Odds
| Me. Spauldings_
No. of I Mar- Mar-
Year Source Repl. N.1No. No.No. No.No.ket- No. 1 No. o. 2 ket-
_____22 1 [ able able
Bliss Triumphs Versus
Spaulding Rose
(10 plots; 68 replications)
I________I Bliss Tri. I Spauldings I I |_
1924 N. Y. Uncert................. 3 17.7 9.527.2 18.8 7.7 26.51 -5.8 23.4 2.6 1.22:1 1.81:1 1.0:1
Minn. Uncert. ............. 2 14.2 12.7 26.9 23.5 17.2 40.7 -39.5 -26.2 -33.9 1.21:1 3.40:1 5.1:1
Wis. Uncert. ................ 2 15.5 12.3 27.8 29.3 13.1 42.4 -47.1 -6.1 -34.4 5:1 1:1 28:1
Wis. Cert. ........ ........ 3 24.8 9.2134.0 16.6 14.8 31.4 49.4 -37.8 8.3 26:1 23:1 13.5:1
1925 Nebr. Cert. .................. 10 71.8 20.5192.3 31.2 18.7 49.9 130.1 9.6 85.0 **M:1 3:1 30:1
1926 Nebr. Cert. (A).......... 6 43.9 14.1158.034.115.4 49.5 28.7 -8.4 17.2 415:1 2:1 65:1
Nebr. Cert. (A)* ......... 10 59.1 9.468.529.4 12.6 42.0 101.01-25.4 63.1 M:I M:l M:l
Nebr. Cert. (B)*.......... 10 44.1 12.156.229.4 12.642.0 50.0-4.07 33.8 M:l 2:1 1:1
1927 Nebr. Cert. ................ 12 46.5 9.155.6147.619.6167.2 -2.3-53.6-17. ............. M:1 1350:1
1928 Nebr. Cert .............- 10 61.111.472.569.9 15.5 85.4 -12.6-26.4-15.0 65: 19230:1 1350:1
Average ................ 39.9 12.0;51.9 33.0 14.7147.7 20.8 -18. 8.8 7:1 37:1 3:1
Irish Cobblers Versus
Spaulding Rose
(8 plots; 56 replications)
S_____Irish Cobs. I Spauldings I ___
1924 N. Y. Cert.-......-----.....- 3 27.5 11.1138.6 19.4 11.230.6 41.7 -.9 26.1 2.5:1 .--...--.... 2.8:1
Mich. Cert. ................ 3 27.8 6.8134.6 21.4 14.5135.9 29.9-53.0 -3. 1.8:1 5:1 ...............
1925 Maine Cert ............... 10 45.0 14.0159.0 31.2 18.7149.9 44.21-25.2 18.2 M:1 M:l 1350:1
Maine Cert.* ........... 2 19.4 12.231.6 26.7 10.1136.8 -27.3 20.8 -14.1 1:1 2:1 2:1
1926 Maine Cert ............... 6 41.6 11.052.634.1 15.4149.5 22.0 -28.6 6.3 9.89:1 267:1 1:1
Maine Cert.* ......... 10 63.2 9.6 72.8 29.4 12.642.0 115.0-23.8 73.3 M:1 M:1 M:1
1927 Maine Cert. ................. 12 62.4 9.3 71.7 47.6 19.667.2 31.1-52.6 6.7 434782:11 M:1 M:l
1928 Maine Cert. .............. 10 59.7 8.768.469.9 15.5185.41 -14.6-43.8-19.8 657:1 M:1 434782:1
Average ................ 43.3 10.3 53.0 34.9 14.7149.6 24.01-29.9 8.7 15:1 103:11 4:1
N. Y. Cert........---------- 3
Mich. Cert. -..------....-- 3
Maine Cert. ..........--..... 10
Maine Cert -..------- 6
Maine Cert.* ....---........ 10
Maine Cert. ............ 12
Maine Cert. .................. 10
Average .............
Mich. Cert. ................
Mich. Cert.* ................
Mich. Cert. ................
Mich. Cert.*..........
Average ..............
i
Green Mountains Versus
Spaulding Rose
S(7 plots; 54 replications)
| Green Mt. I Spauldings I
38.9 13.552.4120.6115.3 35.9
37.3 11.6148.9119.6113.6 33.2
35.0 15.6 50.6131.2118.7149.9
40.1 8.7 48.8 34.115.4 49.5
49.3 14.1 63.4 29.4 12.6142.0
50.6112.7 16.3147.6 19.6167.3
61.4111.4 72.8169.9 15.5 85.4
144.7112.5 57.2136.1 15.8 51.9
Golden Russets Versus
Spaulding Rose
(4 plots; 19 replications)
1 Gold. Rus. I Spauldings
29.0 5.5134.5 20.2 16.6136.81
29.8 11.5141.3 26.7 10.1136.8
35.0 10.1145.1 34.1 15.4149.5
35.4 17.3 52.729.4 12.6 42.0
32.3 11.143.4127.6 13.7 41.3
27:1
1:1
...............
44:1,
27:1
1.5:1
1.6:1
22:1
1:1
22:1
M:1
1350:1
76:1
16:1
2:1
19230:1
1:1
3:1
33.4:1
51:1
................
116:1
M:1
1:1
825:1
27:1
4:1
1:1
11:1
19230:1
2:1
Other Spauldings Versus
Maine Spauidings
(10 plots; 71 replications)
S________Other Spldg. I Me. Spldg. I __
1924 N. Y. Cert. (A)..........-- 3 6.7111.6148.3|20.9112.9133.8 75.61-10.1 42.9 7:1 7:1 6:1
N. Y. Cert. (B)........... 3 22.8112.935.7125.9 10.336.2 -12.01 25.2 -1.4 1.5:1 3:1 .........
Wis. Cert. ................. 3 24.4 13.437.8122.510.8 33.3 8.4 24.01 13.5 9.7:1 11:1 9:1
Minn. Cert. ........... 3 10.710.321.4 19.9 9.9129.8 -46.21 4.01-29.5 16:1 2:1 12:1
1925 N. Y. Cert............... 10 17.114.0 31.1 31.2 18.7149,.9 -45.21-25.1J-37.7 M:1 M:1 M:l
1926 Wis. Cert. ................ 6 29.916.3 46.2 34.115.4 49.5-12.31 5.81 -6.7 11:1 M:1 3:1
1927 "Bill Spud" ............. 11 45.9 17.5 63.447.6 19.6167.2 -3.571-10.7 -5.7 1:1 3:1 -1.6:1
N. Y. Cert............ 12 47.217.264.447.6119.6167.2 -.84-12.2-4.17 .......... 45:1 2:1
1928 "Bill Spud" ............ 10 60.8115.2 76.0 69.915.5185.4 -13.2 -1.91-10.7 267:1 .. ..... 54:1
Prince Ed. Island........ 10 86.112.6 98.7 69.915.5 88.4 23.21-18.71 15.7 19230:1 65:11 657:1
S Average -.--3--..... 18.1 14.1152.2 38.914.8 53.7 -2.0 -4.91-2.81 1:1 4:11 2:1
*Planted at the Everglades Experiment Station, Belle Glade, Florida. **Indicating odds of a million or more to one. Rovs
paired directly in 1924 and odds calculated by means of Love's Modification of Student's Method. The same method was used for
the general averages, and Bessel's method for the'1925, 1926 and 1927 data.
'
88.91-11.8
90.31-14.7
12.21-16.6
17.6-43.5
67.7 11.9
6.3 -35.2
-12.11-26.4
23.81-20.8
~ ~
100:1
90:1
65:1
22:1
M:l1
8:1
116:1
27:1
Florida Agricultural Experiment Station
TABLE II.-AVERAGE PERCENTAGES OF U. S. No. 1 POTATOES PRODUCED BY THE
DIFFERENT VARIETIES IN FOUR YEARS' TRIALS-CONSIDERING PRIMES AND
SECONDS ONLY.
Year 0 0
1925 .......... 76 78 '69 .... .... 62 55
1926 .......... 79 76 82 77 65 69
1927 ......... 87 84 80 .... 72 71 73
1928 .......... 87 84 84 .... 80 82
Average .. 82 80 79 77 72 71 64
TABLE III.-AVERAGE PERCENTAGES OF UNMARKETABLE (NO. 3 AND CULLS)
POTATOES PRODUCED BY THE DIFFERENT VARIETIES IN TWO YEARS' TRIALS.
2 V2 g
Year r 4 A G
1925 ........................ 5.3 7.6 10.0 .... 6.0 10.8
1926 .......................... 5.0 5.0 4.0 4.0 .... 6.0
Average .................. 5.1 6.3 7.0 4.0 6.0 8.4
DISCUSSION
Close analysis of the data reveals that the Bliss Triumphs
significantly outyielded the Spauldings in primes by from 28 to
over 130 percent in 5 out of 10 plots (consisting of 68 replica-
tions). A decrease in the number of barrels of seconds was ob-
tained in eight of the plots, and an increase of marketable tubers
of from 2.6 to 85 per cent is shown in six plots. The general
average of all Triumph plots gives an increase over Spauldings
of 20.8 percent in primes and 8.8 percent in marketable tubers.
These increases, while significant for several years, are hardly
significant when considering the entire five years of trial.
In the eight Cobbler plots (consisting of 56 replications) six
yielded increases over Spauldings of from 22 to 115 percent in
Bulletin 201, Variety Tests of White Potatoes
primes, increases from 6 to 73 percent in marketable tubers re-
sulted in five of the plots, and a decrease in seconds is observed
in all but one plot. The general average of all Cobbler plots gave
an increase over Spauldings of 24 percent in primes, 29.9 percent
decrease in seconds, and 8.7 percent increase in marketable
tubers.
All but one of the seven trial plots (54 replications) of Green
Mountains gave increases over Spauldings of from 6 to 90 percent
in primes, and significant increases of from 45 to 50 percent in
marketable tubers were obtained in three of the comparisons.
Definite decreases in seconds are observed in all but one instance.
The general average of all Green Mountain plots gives increases
over Spauldings of 23.8 percent in primes and. 10.2 percent in
marketable tubers, with a.decrease of 20.8 percent in seconds.
The Russets likewise yielded from 2 to 43 percent more primes
than the Spauldings. These vines, however, were rather green
at digging and the tubers bruised easily. It is doubtful if this
variety is adapted to Florida conditions because of the longer
season which it requires to reach maturity.
The data obtained when comparing Spauldings from other
sources with Maine Spauldings indicate that during these trials
but one lot (from Prince Edward Island) was found which was
in any way superior to the stock obtained in Maine, but some
were decidedly inferior. In 1924 one lot from New York out-
yielded the Maine stock with which it was compared. It was
demonstrated conclusively that that particular lot from Maine
carried an exceptionally high percentage of disease, which fact
caused its absolute rejection in Maine for planting purposes the
following season.
The comparisons in 1927 between Maine and New York
Spauldings were made between lots originating from the same
source, the New York sample coming from the same farm in
Aroostook County, Maine, in 1925 as the 1926 Maine sample
planted in Florida in 1927, but having been grown in New York
one season in the meantime. Here approximately the same
yields were obtained. The Spauldings from the North Central
states have with one exception underyielded in primes the Maine
samples by from 3 to 46 percent. In one instance (1924) a Wis-
consin lot slightly outyielded a Maine lot, both however yielding
very poorly, both being poor samples of seed stock. In another
instance (1927) one lot of "Bill Spud" Spauldings gave practi-
Florida Agricultural Experiment Station
cally the same yield as the Maine sample, but a similar lot greatly
underyielded the Maine samples in 1928.
Under Florida conditions, where all shipments must be care-
fully graded, and where there is such a great price differential
between primes and seconds and practically no market for any-
thing below a U. S. No. 2 grade, the all-important thing to con-
sider is the percentage of marketable tubers, particularly primes,
that are actually produced. More primes and less seconds are
of foremost importance to the Florida growers.
Table II gives the average percentages primes obtained for the
different varieties during several years' trials. While these fig-
ures indicate that Cobblers produce a greater and the Spauldings
a lesser proportion of primes than any other variety (calculating
on the basis of primes and seconds only), it is also worthy of
note that wherever total yields are considered (two years' trials
only) the Spauldings produced consistently the highest and the
Cobblers the lowest percentage of unmarketable tubers (Table
III). The fact that Spauldings have been producing the lowest
percentage primes, or the highest percentage unmarketable
tubers may be explained in part by a comparison of tuber types.
Both Cobblers and Triumphs are more round than the Spauldings
and consequently a larger percentage would be classified into the
U. S. No. 1 grade by the mechanical grader used. It is doubtful
if this same condition obtains for the Green Mountain variety'
where the tubers are more elongated.
It is a well established fact that in Aroostook County, Maine,
the different varieties mature in the following order: Bliss
Triumphs, Irish Cobblers, Green Mountains and Spaulding Rose.
There is not much: difference in time of maturity between the
early varieties, Triumphs and Cobblers, and very little between
the two later maturing Mountains and Spauldings, but there is at
least two weeks or more difference in time of maturity between
these early and the late groups. Five years' observations have
demonstrated that the order of maturity in Florida is identical
with that in Maine. The Cobblers and Bliss Triumphs mature
first and the Mountains and Spauldings at least'10 days later
with a tendency in the Spauldings to be later than the Mountains.
Again examining the yield data it will be observed that this is
the same order, in Florida, for the production of marketable
tubers. Whether or not this is a mere coincidence has not been
determined.
Bulletin 201, Variety Tests of White Potatoes
Investigators in other sections point out that cool weather is
essential at time of tuber setting, and hot weather at this partic-
ular time reduces the yield. Still others suggest that compara-
tively low temperatures are essential for maximum yields
throughout the entire period of tuber development, and that
potatoes should be planted so that tuber maturity coincides with
the close of the growing season. This is applicable to Northern
climates, and their experiments indicate that high temperatures
late in the season retard tuber development. The entire question
is still unsettled. Field observations in the Hastings section in-
dicate that the largest yields are obtained from the later and
last planted fields. This, however, is more or less in direct con-
tradiction with the above idea, as the Florida crop matures as
the temperature increases. Regardless of whether or not the
other varieties produce larger yields because of more favorable
climatic conditions, the fact remains that the Spauldings are
slightly later in maturing, and produce less total and less U. S.
No. 1 potatoes than these other varieties. This is a horticultural
problem which requires careful investigation for a period of
years before definite conclusions can be drawn.
It is thought usually that climatic conditions determine the
varieties which are to be planted in the various sections. Locally,
it is thought that the Spaulding is better adapted to extremes in
temperature than some other varieties. The past five seasons
have been extremely variable in both temperature and precipita-
tion. These data, as given in Table IV, indicate that the first
and third seasons during which these trials were conducted were
comparatively cold and wet. Average conditions prevailed dur-
ing the second season, the fourth was comparatively warm and
dry, while the fifth was abnormally dry for at least during the
first half. Examination of the daily weather records (not given
here) reveals even greater extremes of temperature than are
indicated in the averages given in Table IV. It is doubtful if
much greater variation could be found in any other consecutive
5-year period within the last 20 years. Frost injury was care-
fully observed in 1927 but no difference in recovery from such
injury could be noticed between the varieties. In spite of these
extremes in temperature and moisture the Spauldings have been
outyielded consistently by these other varieties, except in 1928.
It is thought that in 1928, from the standpoint of tuber setting
and later development, the heavy rains occurred at a time which
Florida Agricultural Experiment Station
was more favorable for the later maturing Spauldings than for
the earlier maturing varieties which were already further
advanced in their growth. There undoubtedly is a relationship
between adequate rainfall at the proper time throughout tuber
development and maximum yields, but the general statement
that the Spauldings are more able to endure adverse climatic
conditions appears rather debatable.
TABLE IV.-CLIMATOLOGICAL DATA* FOR HASTINGS, FLORIDA, FOR THE
POTATO GROWING SEASONS OF 1923-1928.
Temperature Data in Degrees Fahrenheit.
I 1923-24 I
1924-25 1 1925-26
Mean
SI S I P
I Mean Mean
i** I ** I **
...... 72.4 53.062.7 72. 50.5 61.5
....... 67. 48.558.0 71. 51.2 61.3
........ 67.8 45.4 56.6 72.5 48.5 60.5
....... 69.648.7 59.2 77.8 50.5 64.2'
....... 79.7 58.9 69.3 81.6 54.6 68.1
..... 86.7163.3 75.084.1 595 71.
1926-27 1 1927-28
Mean Mean
a .5 (I
,g g g g
36.4 45.4 55.9 74.5 50.4
65.3 45.7 55.5 69.0 43.7
71.9 46.5 59.2 78.2 51.7
71.2 48.0 59.6 76.8 50.6
78.7 58.2 66.0 83.9 56.6
36.4159.873.1290.9 60.5
62.4 68.9
56.4 66.7
65.0 71.3
63.7 77.6
70.2 78.4
75.7 83.2
1
46.4 57.6
41.3 54.0
48.3 59.8
51.2 64.4
52.6 65.5
59.671.4
Precipitation Data in Inches of Rainfall.
S 1923-24 1924-25 1925-26 1926-27 1927-28
December .... **1.89 0.33 8.51 1.64 1.58
January ...... 3.43 3.58 3.53 0.44 0.90
February .... 2.80 1.59 1.56 3.79 1.74
March .......... 11.01 2.17 3.61 2.03 2.45
April ............ 2.18 0.62 4.20 0.44 9.08
May ............ 2.99 5.18 1.70 1.15 5.54
*Obtained from the records of the U. S. Weather Bureau.
**The data from December to May, 1923-24, were taken at Federal
Point (but 3 miles from Hastings), as the Hastings Station had not been
established.
During these five years the different varieties were planted
in adjoining rows at the same time, given the same care through-
Dec.
Jan.
Feb.
Mar.
Apr.
May
Bulletin 201, Variety Tests of White Potatoes
out the season, and harvested at the same time. Particular at-
tention was given the matter of foliage production and inhibition
of weed rowth. Spauldings produced probably slightly less foli-
age than either the Triumphs or Green Mountains, and the Cob-
blers slightly less than the Spauldings, but the comparative dif-
ferences were small. In spite of a trifle smaller amount of foli-
age in the Cobblers, no more weediness was observed in the rows
of this variety. Nowhere was there any hint of difficulty from
this source.
Average increases over Spauldings in U. S. No. 1 grade, as
indicated in Table I, of 21, 24, and 24 percent for Bliss Triumphs,
Irish Cobblers, and Green Mountains respectively, indicate pos-
sibilities favorable towards the growing of varieties other than
that which is now grown almost exclusively. However, it is not
within the scope of these investigations to determine whether
or not any white or red varieties would be accepted in large
quantities by the northern markets at satisfactory prices at the
time they are looking for the pink-skinned variety which Florida
is accustomed to ship at that particular time. Considering the
cooking quality of these different varieties, it would seem that
there should be but little difficulty in marketing should they
once become established. Theoretical calculations based on even
the comparatively low averages (see table) obtained during the
five years' trials yield financial increases per acre at Spaulding
sale prices of $5.50 per barrel for primes and $2.50 per barrel
for seconds, as follows:
Bliss Triumphs Spaulding Rose
39.9 bbl. primes...... ......... $219.45 33.0 bbl. primes....................$181.50
12.0 bbl. seconds.................. 80.00 14.7 bbl. seconds................... 36.75
Total .................................. $249.45 Total .................................... $218.25
Balance in favor of Bliss Triumphs..................... ................. 31.20
Irish Cobblers Spaulding Rose
43.3 bbl. primes................ $238.15 34.9 bbl. primes....................$191.95
10.3 bbl. seconds.................. 25.75 14.7 bbl. seconds.................... 36.75
Total ......................... ...........$263.90 Total .....................................$228.70
Balance in favor of Irish Cobblers..................................................... 35.20
Green Mountains Spaulding Rose
44.7 bbl. primes.....................$245.85 36.1 bbl. primes............ $198.55
12.5 bbl. seconds.... .......... 31.25 15.8 bbl. seconds.................... 39.50
Total ....................................$277.10 Total ....................................$238.05
Balance in favor of Green Mountains......................... 39.05
Florida Agricultural Experiment Station
If these varieties could be sold at current Spaulding prices it
is at once evident that during seasons when high yields are pro-
duced or when high prices are received the difference in returns
per acre in favor of any of these other varieties would be much
greater. It requires but little further calculation to realize that
were such an approximate increase of four or five barrels, or of
$25 per acre, possible on the acreage in the potato belt of Florida,
the total increase would go far to pay for the entire 100,000
bags of seed stock imported annually. Should these other varie-
ties net 50 cents less per barrel than Spauldings the income per
acre would still be as much as or more than that realized from
the standard variety now planted. However, all of this can be
determined only by the growers and their selling agencies
through repeated trial carlot shipments. These trials can but
indicate that these other varieties would compare favorably, and
sometimes exceed the Spaulding Rose No. 4 which is at present
the standard variety for Florida.
SUMMARY
Comparative yield studies of several different varieties of
potatoes were conducted in representative localities of the Hast-
ings potato area and the Everglades for the last five years.
These studies consisted of from 4 ts 10 plots with a total of
from 19 to 71 replications per variety as indicated in Table I.
The climatological data show that the seasons during the time
of these experiments were extremely variable, both as to tem-
perature and rainfall. Regardless of such extremes in seasons
the Spaulding Rose No. 4 variety was rather consistently out-
yielded in primes by Irish Cobblers, Green Mountains and Bliss
Triumphs.
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