Part 7
I also planted a Tasterite black walnut in the spring of 1939, and this is the first year that it has borne any nuts. It remains to be seen whether they will be filled out or not. There is, however, an important difference between the Thomas and the Tasterite, which are growing only 50' apart, namely that the Thomas suffers from winter injury to the terminal twigs each year, whereas there has not been any sign of such injury to the Tasterite.
Hickories
I have planted possibly two dozen of a number of varieties of hickories, of which only nine survive to date, the cause being not winter injury but what appears to me to have been improper circulation through the graft union. They would struggle along for three or four years (producing suckers from the root stock which I broke off), and then die. None of these has borne any nuts yet except the Weschcke, which was planted in the fall of 1941, and which is now bearing one nut. This nut is a mystery to me because the tree bore no catkins. There are no hickory trees within thirty miles of the vicinity to my knowledge, and the nearest pignut tree is perhaps three-quarters of a mile distant, in a direction against the prevailing winds, the intervening space being forest. Could it be possible that the Weschcke hickory was pollinated by a butternut or the Broadview Persian walnut? A big butternut tree stands within 60' and the Broadview is situated about 150' distant.
Heartnuts
I have tried a number of heartnuts, including the Gellatly and the Wright. Only a single Gellatly survives. Here again the cause was not winter injury so much as either the butternut curculio or other causes. The Gellatly, while suffering some terminal twig winter injury and deer damage by rubbing of horns, has borne and ripened nuts.
Filberts and Hazelnuts
I planted a number of Winkler hazels in the fall of 1940, and this is the second year of bearing. The nuts hardly have time to ripen in our climate and a good many of the catkins get winter-killed.
In the spring of 1939 I planted a number of filbert seeds received from Mr. Slate such as No. 128 Rush Barcelona; Medium Long; and Red Lambert. These are bearing for the first time this year, and judging from the size of the nuts now, it looks as if they will mature. Many of the catkins were winter-killed.
Bixby and Buchanan planted in the spring of 1939: While the plants did very well, most of the catkins invariably were winter-killed, so I was obliged to pull them up.
I have a feeling that filberts would do better here if it were not for the very cold winds that blow off the lake in winter, killing most of the catkins.
I discovered a wild hazel in Lexington, Mass., (which town is located in a so-called cold air pocket) the nuts of which are almost equal to the Winkler. I have transplanted some of these to Wolfeboro and shall know more about them later. I also discovered some wild hazels in northeastern Maine, between Lincoln and Vanceboro on the border of New Brunswick, Canada, which two weeks ago had good sized, well filled nuts on them. I have also transplanted some of these to Wolfeboro.
In closing I should like to thank all officers, committee members, and others who are responsible for the annual report. To those of us who do not get to the conventions very often, the report is the Northern Nut Growers Association, and a source of very valuable and interesting information, especially to an amateur like myself.
A Simplified Schedule for Judging Black Walnut Varieties
L. H. MacDANIELS and S. S. ATWOOD, Cornell University
All its members would agree that the Northern Nut Growers Association should have an officially accepted schedule for judging black walnuts and the other kinds of nuts with which it is concerned. Some yardstick is needed to serve as a basis for the comparison of varieties which the members of the Association will use. Persons familiar with nut varieties are freqeuntly asked to answer questions about the best varieties to plant. Of course there is no simple answer to such a question as many factors besides the nuts themselves determine the value of a variety. The quality and value of the nuts are, however, the most important initial consideration in selecting a variety on its merit and there should be some objective test adopted to aid in evaluating nut samples.
During the many years that the Northern Nut Growers Association has been operating more than a hundred and fifty varieties of black walnuts have been named. Yet at the present time we are not certain which are the better varieties except in a very general way. There is no widely accepted judging schedule being used as is evident in the tables published by Seward Berhow in his paper in the 1945 Proceedings (2). In these tables scores are given but these come from several sources and are not comparable and hence are of little value in making comparisons.
There have been many schedules for judging black walnuts presented in the past. One of the first was proposed by the late Willard G. Bixby (3, 4). This was complicated and never came into general use although the testing done by Mr. Bixby was a valuable contribution to our knowledge of varieties. The late N. F. Drake tested many varieties through the years according to a schedule of his own devising (5, 6). Professor Drake's schedule was related to his concept of a perfect walnut and the various values were related to this on a percentage basis. This schedule never had wider acceptance, chiefly because it was too complicated and required too much figuring.
Mr. C. A. Reed has probably tested more varieties of nuts and is more familiar with varieties than any other person but he does not have a definite scoring schedule. Kline and Chase (7) summarized results of the testing work that had been done and Kline (8) compared varieties according to a system which he devised in which they were rated in terms of return per hour of labor spent in cracking and extracting the kernels. Mr. C. C. Lounsberry has proposed a method of scoring which was related to kernel cavity measurement (9).
In 1935, a Committee on Varieties and Standards endeavored to formulate a working schedule that would be adopted as official. This committee set up a score that represented the best thinking of the group at that time (1). Twenty-five nut samples were used. The score was the sum of the weight of an individual nut in grams plus twice the per cent kernel of the weight of the nuts recovered in the first crack plus the total percentage of kernel plus 1/10 of a point for each quarter kernel recovered. Penalties were proposed for shrunken kernels and empty nuts. Through the years a large number of samples have been tested according to this scoring schedule (11). In 1943, MacDaniels and Wilde (12) summarized the previous work done, added many tests and evaluated the scoring system. This was not considered to be altogether satisfactory. In the first place, it was somewhat cumbersome and had never been adopted by the Association nor had it been used much by others. The figuring of percentages and penalties made a score too involved for wide aceptance. A very serious difficulty was the problem of shrunken kernels and empty nuts. Obviously, with a score related to the weight of the sample before cracking, the inclusion of a number of empty nuts made it impossible to make any accurate correction in the percentages that were used in the score. Penalties did not solve the problem. Also the initial weight of the sample varied with the amount of husk clinging to the shells. From this work it was evident that an acceptable score would have to be formulated on some other basis.
The next approach was to analyze data of this type statistically in an attempt to devise a better scoring system (1). The results from such a study proved valuable in answering such questions as 1) the size of sample necessary to obtain significant differences between samples; 2) the significance of small differences in measurements or in scores and 3) the amount of variation that is normal and without significance in comparing varieties.
The following qualifications were considered essential to a workable schedule:
1) The schedule must be easy to use.
2) The schedule must concern itself with objective qualities or characters which can be weighed or measured. It cannot be concerned with flavor and other characters upon which there may be disagreement and which depend upon personal preference.
3) Characters must be avoided which vary with the treatment of the samples themselves such as color of kernels.
4) It must give a score that will separate samples on small differences.
Considering the problem from these angles and scrutinizing the older schedules, a number of ideas came out. First of all, why include the shells? If shells are discarded a number of problems would be solved, such as the cleaning of the nuts and adjustments for shrivelled and empty nuts. Also, why reduce any of the weights or measures to percentages which only add to the complexity of the score? The actual amount of kernels recovered reflects both the size of nuts and the yield of kernels. Plumpness of the kernels is reflected in the total weight of kernels and does not need to be considered separately.
The important elements in a score were considered to be:
1) The crackability of the nuts of the variety. This is measured by the weight of kernels obtained in the first crack.
2) The yield of the variety. This is measured in the total weight of kernels.
3) The marketability of the product. This can be measured by the number of pieces in the sample. In general, the smaller the number and the larger the size of the pieces the better the marketability.
With this general background in mind, many samples were tested and the results published in the 1945 report[1]. In order to secure the data needed the kernels of the individual nuts in the samples were weighed separately.
NOTE: All samples were cracked with the (John W.) Hershey nut cracker.
Some of the conclusions drawn from these tests were as follows:
1) Using kernel weights only gives a rapid and accurate test of differences between varieties.
2) Ten nuts are adequate for a single sample.
3) The location of the tree with reference to climate and soil is probably the most important single factor influencing kernel yield. No evidence was obtained, however, to indicate that the varieties ranked significantly different at different locations.
4) If reasonable care is used in cracking the differences due to different operators tend to be non-significant.
The statistical proof that a ten-nut sample is adequate and that differences between operators are not significant are two findings that are important in setting up a schedule.
During the past year further testing has been done, in which scores were computed from ten-nut samples.[A] The samples had preliminary cool, dry storage to assure comparable moisture content. Enough nuts were cracked in each sample to secure ten that were well filled. Empty nuts were recorded. The following data were kept for each sample:
1) The weight of the kernels recovered in first crack in grams.
2) The total weight of the kernels in grams.
3) The number of quarters and number of halves recovered.
Scores were computed as 1) the weight of the first crack in grams plus 2) half of the total weight of the kernels recovered in grams plus 3) the number of quarters divided by four and, 4) the number of halves divided by two. In this score, it was considered that the crackability of the sample was measured by the weight of the first crack; the yield, by the total weight of kernels secured from the sample; the marketability by the number of quarters and halves. From the use of this schedule scores were secured ranging from 83.9 for the variety Thomas grown in Maryland to 37.4 for the variety Huen, which is a small nut giving relatively small kernel yield.
Analyses of the data to determine the percentage of the score that was derived from each component showed that crackability as measured by the weight of the kernels recovered in first crack gave an average of 54% of the score with a range of 49 to 58 for the different samples; yield, as measured by total weight of kernels divided by two, 31% with range of 27 to 34%; marketability measured by number of quarters divided by four 14% with range of 10 to 22% and number of halves divided by two 1%. The percentage of the score derived from the number of halves was so small as to be negligible. It seemed better, therefore, to base the score on only three elements, namely, the weight of the first crack, the total yield of kernels and the number of quarters recovered from the sample.
On this basis the problem becomes that of deciding the weights that should be given to these three components. The score as set up emphasizes the crackability of the variety much more than its marketability. This seems logical because the value of a variety is in large part dependent upon the ease of recovery of the kernels on first cracking. Several different combinations of the weighting of these three components were considered and it was decided that the most logical was to weight the elements as follows: 1) The weight of first crack in grams. 2) The total weight of the kernels divided by two and 3) the number of quarters recovered divided by 2. If there are halves, each half would count as two quarters.
Table I. Average scores from 18 black walnut samples cracked by three operators and computed by two scoring systems.
Scoring Systems[3] -------------------- Variety Source Year I II points points Thomas Maryland '46 83.9 93.1 Snyder Ithaca, N. Y. (A) '46 81.8 89.2 Ohio Maryland '46 79.5 88.9 Thomas Ithaca, N. Y. (A) '46 76.4 85.5 Norris Tennessee '45 76.1 83.9 Stambaugh Ithaca, N. Y. (A) '46 75.9 81.0 Stambaugh Ithaca, N. Y. (A) '46 74.0 83.2 Thomas Tennessee '45 71.5 79.6 Thomas Ithaca, N. Y. (B) '46 65.7 74.6 Cornell Ithaca, N. Y. (C) '46 59.3 67.6 Stabler Maryland '45 56.9 64.5 Cresco Ithaca, N. Y. (A) '46 55.8 65.2 Seedling No. 1 Geneva, N. Y. '46 52.7 62.2 Seedling No. 3 Geneva, N. Y. '46 50.6 59.0 Brown Ohio '45 49.7 59.4 Stabler Tennessee '45 47.5 51.4 Seedling No. 2 Geneva, N. Y. '46 44.4 52.2 Huen Iowa '46 37.4 44.9 Least significant difference (5%) 6.3 6.6
[Footnote 3: Score I=Weight (grams) 1st crack + Total weight (grams) + -------------------- 2
Number quarters + Number halves --------------- ------------- 4 2
Score II=Weight (grams) 1st crack +
Total weight (grams) + -------------------- 2
Number quarters --------------- 2 ]
Calculating the percentage of each component in the total score on this basis gives crackability 48%, yield 27%, marketability 25%. This schedule gives relatively more weight to marketability as against the other two components. The average scores of 18 samples cracked by three operators and calculated on both the above described schedules are given in table I.
The table shows that the rank of the different samples was not changed materially by using only the three components, except in a few cases in which there were an appreciable number of halves. The Stabler has many one-lobed nuts which increase the number of halves recovered. It is to be noted that with both schedules the least significant difference at the 5% level is about 6 score points.
Table II gives the score calculated by schedule II for five samples, each cracked by six operators. The difference between operators is not significant but the difference between varieties is highly significant.
Table II. Scores from five samples of black walnuts each cracked by six operators according to scoring schedule II.
Operators ---------------------------------- Variety Location Year 1 2 3 4 5 6 Average
Snyder Ithaca, N. Y. '46 89.2 87.3 78.9 94.4 87.5 91.5 86.5 Thomas Ithaca, N. Y. (A) '46 83.5 79.2 83.1 78.0 84.2 83.8 83.6 Thomas Ithaca, N. Y. (B) '46 73.1 67.4 73.4 74.1 69.6 83.8 73.6 Cresco Ithaca, N. Y. '46 66.0 69.2 63.1 67.2 68.5 60.2 65.7 Brown Ohio '45 62.5 51.0 65.4 60.4 48.1 64.8 58.7 ------------------------------------------------------------------------- Average 74.9 70.8 72.8 72.8 71.6 78.8 73.6 Least significant difference (5%) for variety averages 6.2
A third scoring system, involving 1) weight of kernels in grams for the first crack, plus 2) total weight of kernels, 3) all divided by the number of marketable pieces (as counted following sifting on a 1/4" round hole screen) was tried, and the resulting ranking of the varieties was very similar to that obtained with systems I and II. The results from this system appeared to be the most precise, but it was not considered as generally acceptable as system II, since the latter would be easier to record and calculate.
It is the opinion of the authors that Schedule II gives a score that estimates very well the relative merit of the samples tested as to crackability, yield and marketability. It is simple to use and the only equipment required is a scale accurate to 1/10 gram. Calculations are reduced to a minimum and the characters used are not dependent on judgment of the individual making the test. It should be pointed out, however, that differences in score of less than six points are not significant on the basis of testing done to date. As more tests are made this value may be reduced. The schedule should serve as a measure to establish differences between varieties, particularly when a considerable number of tests are made. It can also be relied upon to measure differences due to the location of trees of the same variety, variation of the same variety from year to year in the same and in different locations and differences of a similar nature. In ranking varieties which have scores within the limits of variability, it will be necessary to use judgment as to small differences of appearance. No scoring schedule can be expected to entirely eliminate the judgment of experts. Also it must be realized that characters other than the nuts, such as bearing habit, hardiness, yield of trees, disease resistance and the like must be considered in finally establishing the value of a variety.
References Cited
1. Atwood. S. S. and L. H. MacDaniels. Tests of black walnut varieties for differences in kernel yields. N.N.G.A Rept. 36: 44-50, 1945.
2. Berhow, Seward. Black walnut variety tabulations. N.N.G.A Rept. 36: 38-43, 1945.
3. Bixby, W. G. Judging nuts. N.N.G.A. Rept. 10: 122-133, 1919.
4. ----. The 1929 contests and the method of testing used. N.N.G.A. Rept. 22: 42-63, 1931.
5. Drake, N. F. Judging black walnuts. N.N.G.A. Rept. 22: 130-137, 1931.
6. ----. Black walnut varieties. N.N.G.A. Rept. 26: 66-71, 1935.
7. 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.
8. Kline, L. V. A method of evaluating the nuts of black walnut varieties. Am. Soc. Hort. Sci. Proc. 41: 136-144, 1942.
9. Lounsberry, C. C. Measurements of walnuts of United States. N.N.G.A. Rept. 31: 162-127, 1940
10. MacDaniels, L. H. Report of committee on varieties and judging standards. N.N.G.A. Rept. 28: 20-23, 1937.
11. ----. Is it possible to devise a satisfactory judging schedule for black walnuts? N.N.G.A. Rept. 30: 24-27, 1939.
12. ----, and J. E. Wilde. Further tests with black walnut varieties. N.N.G.A. Rept. 34: 64-82, 1943.
Test Plantings of Thomas Black Walnut in the Tennessee Valley
SPENCER B. CHASE, Tennessee Valley Authority
Native black walnut occurs abundantly throughout most of the Tennessee Valley. Practically every farmer has at least one "favorite tree" and each fall he collects nuts from that tree and stores them for cracking during the winter. In some sections of the Valley walnut cracking in the home is of considerable importance. Each year, some million and a quarter pounds of kernels are cracked out at the five modern cracking plants located in or adjacent to the Valley. Utilization of the crop is becoming more and more complete.
In early studies of native nut trees, TVA recognized the possibilities of black walnut, especially the improved varieties. Here was a tree that produced not only valuable nut crops but also cabinet wood without equal; in addition, it was a desirable pasture shade tree. Black walnut has long been a favorite among farmers, but few of them had ever heard of =improved= black walnuts. Along with TVA, the state agricultural extension services saw the advantages of the improved varieties and were eager to test them under Valley conditions. And so it was that a cooperative testing project was developed. TVA produced the trees and the seven Valley state extension services distributed them to farmers for test planting.
The Test
The Thomas walnut was used in these test plantings for several reasons. In the first place, it produces large, rather thin-shelled nuts with good cracking qualities. Few varieties are more easily cracked with a hammer or a hand-operated cracking machine. In addition, fast growth is characteristic of the variety and it should produce merchantable sawlogs earlier than the common walnut. Despite its northern origin, 5-year-old plantings at Norris, Tennessee, seemed well adapted to Valley conditions. No other variety at the time offered as many advantages.
Test planting was begun in Tennessee in 1939 and then it was extended to the other Valley states as more trees were propagated. For the most part, planting sites were selected by extension foresters and county agents. If the tests were successful they would automatically become demonstrations, so special attention was given those areas where walnut cracking in the home was an important enterprise. Many of the test plantings were located in communities that had been organized for the study and application of improved farming methods. In general, farmers planted the trees in low, fertile spots not suitable for other uses, along fences, or in pastures if they could be protected from livestock.
Through 1946, 9,614 trees were planted in 3,286 test plantings. They were scattered all over the Valley, in 92 of its 125 counties. The number of trees per planting varied with the availability of good walnut sites. Generally, there were 2 to 4 trees in each planting.
The Results
Getting survival and performance data on these widely scattered experimental plantings presented quite a problem. Examination of a few plantings showed that trees given reasonable care had survived and were beginning to bear nuts. So in 1946, the farmers who had planted the trees were polled by mail for an overall evaluation of the plantings. Questionnaires asking for information on survival, growth, and bearing were sent by the state extension foresters to 3,274 farmers. The return of questionnaires was excellent. Forty-two percent came back and three-fourths of them were filled out completely.
=Survival and Mortality Causes.= Eighty-one percent of the 1,373 plantings reported on were still active in 1946; that is, they still had at least one living tree. Survival reports received on 3,831 trees planted showed that 2,439 or 64 percent of the trees were living in 1946. Survival was best in the portion of the Valley north and east of Chattanooga; 84 percent in Virginia, 71 percent in North Carolina, and 66 percent in eastern Tennessee. South and west of Chattanooga survival percent was lower: 62 in Georgia, 61 in western Tennessee, 54 in Kentucky, 45 in Alabama, and 26 in Mississippi (Table 1).