Ohio No. 13 Soaked 15.9 25.8 26.4 93 -1. 89.0 1 empty
Ohio No. 14 Soaked 15.7 25.2 26.3 96 - .5 88.4 1 shriveled
Ohio No. 20 Dry 16.7 25.3 26.4 94 -1. 88.9 1 empty
Operator 1
Grundy No. 1 Dry 23.8 24.1 24.6 99 - .5 93.7 1 shriveled, 2 bnd.
quarters
Grundy No. 2 Soaked 23.2 24.2 24.2 100 - .5 97.2 All out 1st crack,
5 halves
Operator 2
Grundy No. 3 22.4 24.0 24.0 88 -2. 89.2 Empty
Grundy No. 4 Dry 23.5 24.7 25.5 98 - .5 95.0 1 shriveled
Operator 1
Adams No. 1 Dry 14.2 18.3 24.5 70 0. 70.0 35 bnd. qtrs., well
filled, good quality
Adams No. 2 Soaked 14.4 17.3 23.7 78 -2.5 67.1 2 empty, 20 bund.
qtrs., 1 shr.
Operator 2
Adams No. 3 Dry 14.6 18.1 24.0 77 -3. 67.5 3 empty
Adams No. 4 14.3 19.6 25.4 78 -2. 72.3 2 empty
-------------------------------------------------------------------------------
The average scores of all samples of each variety are Ohio 90.0, Thomas
83.4, and Ten Eyck 82.4. These are not out of line either with the
scores obtained for these varieties elsewhere or the relative merit of
the varieties.
Because of the variability obtained in the tests shown in Table 4,
another series of tests of similar samples by different operators was
arranged in the summer of 1943. The samples of Ohio were some of the
same lot reported in Table 3. The varieties Grundy and Adams grown in
Michigan were carefully sampled to give comparable lots. The results of
these tests given in Table 5 show no greater variability between the
scores of the two operators for any one variety than between tests by
the same operator and indicate that it is possible for different
operators to obtain comparable scores on duplicate samples provided
great care is used in treating and cracking the samples.
The differences in average score between the different varieties is
consistent and apparently gives a correct indication of their relative
merit. Grundy shows an average score of 93.7, Ohio 89.7 and Adams 69.2.
The high score of Grundy is related to the large size of nut and high
per cent first crack. The low score of Adams is related to small size of
nut and low per cent first crack resulting from a large number of bound
quarters. The kernels of this variety were plump, filling the cavity of
the shell full and shattered on cracking.
In Table 6 are given the results of 54 tests of 38 selections or clones.
In general it appears that the score is a fair indication of the worth
of the sample. Low scores are related mostly to low per cent first crack
and to the presence of empty nuts or shrivelled kernels in the sample.
It is evident also that if a sample is too dry with many varieties a low
score will result. Just what soaking treatment is most expedient is not
too clear. Soaking 12 hours and drying 24 proved to be a satisfactory
practice. The method followed by Mr. Stoke of soaking for 5 minutes and
keeping the sample in a wet burlap sack for 24 hours is all right but is
cumbersome if many samples are to be tested. Soaking one hour and
holding 24 hours in a closed container like a coffee can give good
results but percentage should be figured on dry weight and kernels
should be air dried for 24 hours before weighing.
One weakness in the schedule is that it tends to give a small nut an
advantage if the per cent kernel obtained in first crack is high. Thus a
sample of the Mintle grown in Iowa which weighed but 13.6 grams per nut
and total per cent kernel of 32 scored 101.1 points chiefly because the
per cent first crack was 31.5. The same variety grown at Ithaca weighing
13.7 grams per nut but with 23.9 per cent first crack and 24.3 total
scored 83.8. Possibly a penalty could be taken for nuts weighing less
than 18 grams. On the other hand a large nut like the Grundy weighing
about 23 grams would have a 10 point score advantage over Mintle and
this may be enough for this character.
The six samples of Thomas grown on different trees in Ithaca, N.Y. in
1942 show great variation in score as has been the case in other years.
Poor scores are related to shrunken kernels and such samples come from
trees that are making poor growth because of poor soil conditions and
competition with weeds. Also shriveled kernels are the result of
defoliation by early frosts which may be very local and affect some
trees and not others.
TABLE 6
Tests and Scores of Black Walnut Varieties from Various Sources. 25 nut
samples unless otherwise indicated. All scores figured on basis of 25 nuts.
KEY: A - *Treatment
D--Dry
S--Soaked
No.--Hours dried or soaked
B - Wt. 1 nut grams
C - % kernel 1st crack
D - % kernel total
E - Quarters number
F - Penalty
G - Score
--------------------------------------------------------------------------------------------------
Variety Source A B C D E F G Remarks
--------------------------------------------------------------------------------------------------
Adams Becker, Mich. D 14.7 11.3 21.4 44 52.4 Poor; 62 bound quarters
'42
Benton Smith, Wassaic, S-5 13.2 26.8 28.2 94 -2.0 88.5 Plump kernels, good flavor,
N.Y. 2 empty
Sample No. '42 D-8 nuts
1 (23)
Sample No. " D 12.9 23.1 23.6 74 -3.0 75.3 3 empty nuts
2 (24)
Bontz Snyder, Iowa S-12 18.7 20.3 22.0 85 -10.0 68.8 Nut long like Ohio. Shell
'40 D-12 chamber smooth. Nearly all
kernels shrunken.
Prominent spur; oily; poor
to med. extr.; few shrunken
Boothe Stoke, Va. S-16 15.3 24.5 29.2 87 -2.5 85.1 Good quality; flavor good, 28
'40 D-10 blind qtrs.; ext. poor
Burrows Snyder, Iowa S-12 17.5 13.5 24.4 35 -0.3 59.9 No data
'40 D-4
Calhoun Becker, Mich. D 15.4 26.0 28.5 94 90.6 End cracks, 2 empty nuts,
'42 3 shr.
Cayuga Ithaca, N.Y. S-12 13.8 26.1 26.7 100 -3.5 85.9 kernels, good extr.
middle '42 D-24
tree
Climax Becker, Mich. D 17.2 25.3 27.3 90 90.8 Some shrunken kernels
'42
Cornell Ithaca, N.Y. S-12 16.5 24.9 25.1 80 89.0
(20) '42 D-24 100% No empty nuts, kernels full,
Creitz Stoke, Va. S-15 18.8 22.0 23.8 100 -1.3 83.4 very good extr., good color
'40 4-4 Excellent cracker. Shell thin;
Cresco Ithaca, N.Y. S 16.7 15.9 21.0 80 67.0 thin; good nut; flavor mild
(6) '42
Eldridge Geneva, N.Y. S-12 Not promising at Ithaca
(15) '42 D-24 21.1 24.0 24.5 96 -10. 80.0 Dried in husk; kernels
shrunken
Finney Snyder, Iowa S-12 19.5 18.0 22.4 82 -12.5 62.4 Shell thick; kernels shr.,
'40 D-48 spurs prominent. Tough to
crack
Freel Ithaca, N.Y. S 12.1 17.9 19.6 80 65.7 Shell thick, kernel thin. Not
(6) '42 a good nut
Galloway Snyder, Iowa S-12 16.4 22.3 23.2 94 -0.3 81.7 Kernel smooth, flavor good.
'40 D-24 Extraction good
Harris Snyder, Iowa S-12 18.5 23.8 25.6 100 -12.5 76.4 Dark color. All kernels
'40 D-12 withered. Flavor poor.
Extraction very good
Homeland Stoke, Va. S- 5 19.1 20.4 25.8 89 81.7 Smooth kernels; flavor good;
(19) '40 D-16 closed suture
Karnes Stoke, Va. S-16 20.3 25.6 29.4 56 91.8 Tight in shell. Kernels oily,
'40 D- 7 shatter. Flavor good.
Shining pellicle
Korn Korn, Mich. D 16.8 19.0 27.9 62 74.9 Kernels fill cavity very full.
'39 Shatter
McCoy Snyder, Iowa S-12 19.4 20.7 21.2 90 -0.8 79.6 Smooth kernel; some slight
'40 D-4 shrinking. Thick shell
McGee Becker, Mich. D 13.7 16.2 26.8 83 67.8 Bound qtrs., hard pointed
'42 nuts, hard cracking
Michigan Korn, Mich. '39 D 20.0 23.0 30.3 90 90.1 Kernels plump, very good nut
Mintle Snyder, Iowa S-12 13.6 31.5 32.0 95 -1.0 101.1 Flavor mild, extr. very good.
'40 D-12 Very good nut, smooth shell
Mintle Ithaca, N.Y. S-12 13.7 23.9 24.3 100 83.8 No empty nuts, kernels plump,
'42 D-24 good extraction
Ohio Snyder, Iowa S-12 18.5 24.0 27.4 79 -1.3 86.8 Shell chamber smooth. Flavor
'40 D-24 sharp. Extraction fair.
Rohwer Snyder, Iowa S-12 21.5 24.0 28.2 84 92.0 Kernel smooth, extr. fair.
'40 D-48 Kernels plump.
Rohwer Stoke, Va. S-15 18.5 18.0 22.4 79 - .3 73.3 Fair extraction; flavor fair.
'40 D- 3 Spur prominent. 11 blind
qtrs.
Schwartz Snyder, Iowa S- 6 20.3 21.8 25.6 86 -3.0 82.2 End cracked. Spurs prominent.
'40 D-14 Some shrinking. Not too good.
11 blind qtr.
Sifford Stokes, Va. S-16 23.6 23.7 25.6 100 -11.0 82.8 Large nut. Good extr. Kernels
'40 D-7 shrunken
Snyder Jacobs, Ohio D 19.6 26.1 28.0 94 95.4 Not entirely cured
(4) '42
Snyder Smith, Wassaic, D 21.9 22.0 26.4 91 88.2 11 bound qtrs. Kernels lg.
(14) N. Y. '42 rather dark, a good nut
Sparrow Ithaca, N.Y. S-12 15.5 20.7 22.4 42 -14.5 63.2 1 empty, all shrunken, end
(11) '42 D-24 96% cracks; poor quality
Sparrow Smith, Wassaic, D 16.5 21.6 28.2 85 82.3 Well filled, kernels bright,
(10) N.Y. '42 good flavor, good nut
Sparrow Snyder, Iowa S- 6 16.1 25.1 31.2 84 90.3 Flavor good; smooth nut, spur
'40 D-19 medium prominent. 13 blind
qtrs.
Sper Becker, Mich.
'42 D 16.2 20.0 25.6 90 78.0 Kernels somewhat shrunken
" D 16.7 27.9 28.7 98 96.6 No. 4, 1942 not completely
Sper dried. Not recleaned
Stabler Stoke, Va. S- 5 14.5 20.2 22.8 80 -9.0 65.3 Flavor mild. Easy extr. 12
'40 D-20 blind qtrs. Many shrunken
Stabler Wilkinson, Ind. S-12 14.9 25.7 27.2 77 -3.0 84.6 End cracks; 6 bound qtrs. 2
'40 D-24 empty nuts, 2 shr. kernels
Stambaugh Graham, Ithaca,
(7) N.Y. recleaned 19.3 24.0 24.0 28 -12.5 61.3 All kernels shrunken. Poor
S-12 D-24 100% quality
Sterling Korn, Mich. D 19.8 25.2 25.9 97 92.8 Kernels plump. Very good nut
'39
Tasterite Graham, Ithaca, N.Y.
(4) N. Y . recleaned 13.5 25.0 25.0 100% 86.0 All kernels plump; quality
'42 S-12 D-24 fair
Thomas Snyder, Iowa S-12 17.2 22.9 25.6 91 -1.0 83.9 Good extraction. Some
'40 D-12 shrunken
Thomas Wilkinson, Ind. S-12 18.5 21.5 27.1 26 77.7 End cracks; 21 bound qtrs.,
'40 D-24 Kernels plump; oily,
clinging
Thomas No. Ithaca, N.Y. D 20.6 19.1 22.1 96 79.4 Some shrunken
1 '42 Tree 1
Thomas No. Ithaca, N.Y. S-1-1/2 20.6 14.4 18.2 91 -1.0 67.6 1 empty nut; some shrunken
2 No. 2 '42 D-6
Thomas No. Ithaca, N.Y. D 20.4 19.1 22.1 96 79.2
3 No. 3 '42
Thomas No. Ithaca, N.Y. D 20.1 15.5 16.8 82 -16.0 36.2 4 empty nuts; all shrunken
4 '42 No. 4
Thomas No. Ithaca, N.Y. S-12 20.5 23.4 24.0 90 -8.0 80.5 4 empty nuts; 8 shr. kernels;
5 (24) 2 blind qtrs.
Thomas Ithaca, N.Y. S-12 19.8 17.6 18.4 94 -10.0 63.7 2 empty nuts; 16 shr. kernels
(20) No. 6 '42 D-24
Thomas Wilkinson, Ind. S-12 20.5 21.1 25.4 69 -7.0 75.3 3 empty nuts; 4 shr. kernels,
'40 D-24 23 bound qtrs.
Troup Graham, Ithaca, S-12 16.0 16.0 18.0 16 -20.0 51.0 All kernels shr., 2 empty
(4) N.Y. '42 D-24 100% nuts, quality poor
Vail Ithaca, N.Y. S-12 15.3 20.8 21.8 30 4 empty nuts, 6 shr. kern.,
(8) '42 D-24 94%-17.0 60.2 2 blind qtrs., end cracks
Vandersloot " S-12 27.5 13.4 16.6 58 -3.0 64.4 1 empty nut, 4 shr. kern.,
D-24 11 bound qtrs., ext. poor
Wiard Snyder, Iowa S-12 18.8 26.8 29.4 83 95.4 One of best, well filled.
'40 D-12 Smooth kernel, good flavor,
good extraction
DISCUSSION
In the light of the data presented some conclusions can be drawn on the
various questions raised at the beginning of this paper. It is evident
that if approximately the same score is to be obtained by one operator
on duplicate or replicate random samples, great care must be used in
sampling. There is a tendency in taking samples to pick out the larger
nuts or in some other way fail to take a good random sample. Selections
submitted for contests are likely to be quite misleading as to the value
of the variety and reflect in considerable part the contestant's skill
in selection rather than the merit of the clone. The Freel walnut seems
to be an example of this. At least as grown at Ithaca it is very
disappointing.
It is evident that if comparable scores are to be obtained the samples
receive the same treatment particularly as regards moisture content.
Samples should be dried sufficiently to show the shrinkage of poorly
developed kernels but in no case be allowed to dry to the point of
checking the shells. Uniform soaking practice is a step in the right
direction. A green or partially dried nut will test much higher than one
properly cured as evidenced by Snyder, sample 6 and Spear, sample 7 in
Table 1.
It seems probable that no schedule can be devised that will eliminate
the necessity for skill on the part of the operator. To obtain
satisfactory uniformity in scores, it is essential that the operator be
skilled in the use of the cracking machine and use continuous care in
applying the necessary pressure and in holding the nut in the anvils.
Undercracking or overcracking, reversing the ends of the nut in the
anvil or failure to hold the nut vertical may affect the score.
The presence of empty or poorly filled nuts in a lot of nuts from which
samples are taken at random introduces greater variability in the
samples than that found in lots with all nuts filled. This is true
because the chances of getting an equal number of empty nuts in 25 nut
samples are small and the presence of each empty nut decreases the per
cent kernel and also the numbers of quarters possible. Variations due to
empty nuts could be eliminated by greatly increasing the number of nuts
in the sample but this is not practical for the purposes this schedule
is intended to serve.
The question of whether or not it is possible for different operators to
obtain equal scores on duplicate samples is not satisfactorily answered
by the data in table 4. As the data stand the scores are far from equal.
There is, however, a consistency in the scoring of each operator and it
is quite probable that with more uniform treatment of nuts before
cracking and more careful sampling better agreement would be achieved.
This is borne out in the data given in table 5 in which the variation in
scores between the two operators was no greater than that obtained by
the same operator.
From a study of the data secured it appears that the causes of variation
in the scores of duplicate or replicate samples are the result of (1)
lack of care in making replicate random samples, (2) differences in
treatment of samples before cracking, particularly as regards moisture
content, (3) differences in the skill or care of the operator making the
tests, (4) presence of empty nuts or shrivelled kernels in the sample
which introduces variation not compensated for in a 25 nut sample and
further complicates the matter because assigning penalties for
shrivelled kernels involves personal judgment.
The first three of these can be minimized or eliminated by care and
skill. The fourth item is not so easy but procedure can at least be
standardized. Increasing the size of the sample is not practical if much
testing is to be done.
All things considered it would seem that the scores indicate fairly well
but not accurately the relative merit of the samples and thus can be
relied upon to determine the relative merit of a variety or clone, the
suitability of the variety for growing in a given locality and the
variability of a variety grown in the same region but under different
conditions. To determine the merit of a variety as compared to another
both must be grown under the same conditions. The over-all value of a
variety can only be determined from samples of well filled nuts. In any
case the more samples tested the better.
The following suggestions are made as to procedure:
1. In taking a random sample no selection as to size, uniformity, or any
other quality should be made. Suggested procedure would be to scoop up
about 25 nuts in a berry basket or with the hands from the main supply
and reduce the sample to 25 without conscious selection. What we in the
Northern Nut Growers' Association want is a measure of the merit of the
crop of the tree or variety in question and not the value of a highly
selected sample.
2. It is not practical to bring samples to a uniform moisture content
before cracking is done. The following precautions, however, may be
followed: (a) Take care to see that nuts are reasonably well cleaned and
free from fragments of husk. Scrubbing or beating the nuts together in a
sack will usually remove most of the loose material. Of course the best
practice is to wash the nuts immediately after shucking. (b) Cure
samples until they are dry enough not to lose more weight preferably in
an unheated room. This takes at least a month or 6 weeks. (c) Avoid
storing the samples in a heated room where they will become so dry that
the shells will check or crack. If this occurs the normal cracking
fracture of the shell is destroyed and a satisfactory test cannot be
made. (d) Nuts that have become so dry that the kernels shatter may be
moistened by soaking about 2 hours in cold or lukewarm water then
holding them in a moist condition for 18-24 hours, followed by drying
for 10-12 hours before cracking. Nuts that are to be soaked should be
weighed before soaking and the dry weight used in figuring percentages.
The kernels of soaked nuts should be dried for 24 hours before weighing,
preferably under the same conditions in which the samples were stored
before weighing.
3. Care and skill on the part of the operator are of the greatest
importance, particularly in the thoroughness of cracking. The most
important variable in the score is the per cent kernel recovered at
first cracking. The score is reduced by undercracking the nut so as to
leave the quarters bound or by overcracking to the point of smashing the
kernels. If the nuts have a long point so that the rims of the anvils do
not contact the shoulders of the nut, poor cracking will result. At the
present time a cracker with interchangeable anvils is not available.
Using different sized iron pipe couplings in a vise may help solve the
problem. Some varieties will crack better with a hammer than with a
cracker of the Hershey type with standard anvils. In cracking a sample
for test the operator should try to recover the most possible out of
the first crack without using a pick or recracking.
4. The empty nut problem is probably the most difficult and is not
satisfactorily solved by cracking nuts in excess of 25 until 26 filled
nuts are secured. This necessitates weighing the sample after the nuts
are cracked which is usually impracticable because of loss of parts of
shells in cracking and because additional nuts are not available. Empty
or shrivelled nuts in a sample are a serious defect which should count
heavily against it. On the basis of experience it seems that a better
method is to crack the random sample of 25 nuts and let the empty nuts
and shrivelled kernels affect the score as reduced weight per nut,
reduced per cent kernel and the penalty as well. Shrivelling that is
obvious and which adversely affects the appearance of the kernels should
be penalized. Possibly further experience will suggest a better way of
handling this problem.
The proposed score of a sample is made up as follows:
1. The weight of a single nut in grams.
2. The per cent kernel of total weight of sample recovered after first
crack x 2.
3. The total per cent kernel of total weight of sample divided by 2.
4. One tenth point for each whole quarter recovered.
5. Penalty of one score point for each empty nut in the sample.
6. Penalty of 1/2 point for every nut with shrivelled kernel.
The makeup of this score does not differ from that previously used
except in the matter of procedure with empty nuts. It is felt that the
items included are weighed in a realistic manner and that difficulties
in scoring have been due to methods of handling the samples rather than
in the scoring schedule itself. It does not seem likely that this
schedule or any schedule will be valuable unless used by experienced
operators who are willing to take the precautions indicated. Also it is
apparent that wherever possible more than one sample of a lot to be
scored should be tested and the average score used.
REFERENCES CITED
1. MacDaniels, L. H. Report of committee on varieties and judging
standards. No. Nut Growers Assn. Proc. 28: 20-23. 1937.
2. MacDaniels, L. H. Is it possible to devise a satisfactory judging
schedule for black walnuts? No. Nut Growers Assn. Proc. 30: 24-27. 1939.
3. Kline, L. V., and S. B. Chase. Compilation of data on nut weight and
kernel percentage of black walnut selections. Am. Soc. Hort. Sci. Proc.
38: 166-174. 1941.
4. Kline, L. V. A method of evaluating the nuts of black walnut
varieties. Am. Soc. Hort. Sci. Proc. 41: 136-144. 1942.
5. Lounsberry, C. C. Measurements of walnuts of United States. No. Nut
Growers Assn. Proc. 31: 162-167. 1940.
6. Drake, N. F. Judging black walnuts. No. Nut Growers Assn. Proc. 22:
130-137. 1931.
7. Drake, N. F. Black walnut varieties. No. Nut Growers' Assn. Proc. 26:
66-71. 1935. Nut Growers Assn. Proc. 30: 81-83. 1939.
Shelling Black Walnuts
_By G. J. KORN, Berrien Springs, Michigan_
The methods used in the shelling of black walnuts by one of the
commercial growers in southeastern Pennsylvania may be of interest to
some of our NNGA members. For the last three seasons I have helped this
grower with the harvesting and shelling of his crop. The Thomas variety
predominated in his 40-acre nut orchard. This variety is truly a very
outstanding nut when properly grown. The Thomas is large, cracks well,
its kernels may be readily removed in large pieces, mostly quarters, and
they are of excellent flavor and color.
Care in selecting the orchard site, soils, methods of cultivation,
fertilizing and spraying appear to be of prime importance in the
production of high quality nuts. The matters I shall speak of in this
article, however, will have to do mostly with the harvesting, husking,
curing and cracking of the walnuts and picking their kernels.
When the walnut husks may be easily dented with the thumb they are ready
to gather. This is usually about October 5 in that locality. The
harvesting is begun immediately, as the kernels will become somewhat
damaged as to flavor and color if the husks are allowed to darken and
decompose. When the nuts have ripened they do not remain in prime
condition for harvesting for more than about 10 to 15 days. By this time
the husks will have begun to decompose and darken the kernels. Just as
soon as the nuts are ripe they are shaken from the trees. The nuts are
gathered into bushel baskets and hauled in a pick-up truck to the
husker. One of the old cannon type corn shellers, once quite common in
Pennsylvania, is used to husk the nuts. A farm tractor furnishes the
power to run the husker. The nuts are run through the husker a couple of
times to assure a clean job of husking. The cleanly husked nuts drop
into a basket at the end of the husker. Only 3 minutes or slightly more
time is required to turn out a bushel of husked nuts. The freshly husked
nuts are washed in a large copper kettle of water by vigorously stirring
them a few minutes with a common garden hoe. About 1-1/2 bushels of nuts
are washed in each batch. All nuts that float lightly on the water are
skimmed off and discarded. The nuts are then spread out about 2 or 3
nuts deep on trays to dry. The frames of the trays are made of 1x3 inch
lumber and are 1-1/2 feet wide and 3-1/2 feet long; 3/4 inch mesh
galvanized chicken wire netting forms the bottoms of the trays. Walnuts
dried indoors in the shade produce lighter colored and finer flavored
kernels than do those dried outdoors in the sun and rain. When nuts are
being dried indoors, care should be taken to see that they have a good
circulation of air or the nuts may start molding in the early stages of
their curing. Although the outside of the walnut shells may dry off
quite rapidly, it takes considerable more time for the inside of the nut
to cure properly for storing. The nuts should be left on the trays for a
few weeks to insure thorough curing.
[Illustration]