TABLE 5
Tests by different operators on duplicate samples of black walnuts,
soaked and unsoaked. 25 nut samples. 1942 crop.
| Sample | Treatment | Wt 1 nut grams | % kernel 1st crack | % kernel total | Quarters number | Penalty | Score | Remarks |
|---|---|---|---|---|---|---|---|---|
| Operator 1 | ||||||||
| Ohio No. 1 | Dry | 16.8 | 26.1 | 27.6 | 97 | —4. | 88.5 | 5 bnd. qtrs., 18 shr., 8 halves |
| Ohio No. 2 | Soaked | 16.7 | 27.3 | 27.8 | 99 | —1.5 | 93.5 | 2 bnd. qtrs., 1 shr., 1 empty |
| Operator 2 | ||||||||
| Ohio No. 6 | Dry | 15.9 | 26.3 | 26.7 | 93 | —1. | 90.2 | 1 empty |
| 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 | 89.0 | 1 shriveled |
| Ohio No. 20 | Soaked | 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 | 1 shriveled, 2 bnd. quarters |
| Operator 2 | ||||||||
| Grundy No. 3 | 22.4 | 24.0 | 24.0 | 88 | —2. | 89.2 | 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 | —3 | 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.