From the comparatively modest percentage of catches, 51.5% on the average in 1923 and 37.9% in 1924, one might hastily conclude that the grafting was not skillfully done or that the grafts did not have proper attention afterward, but as noted above the grafting was done by Dr. Deming, whom I regard as one of the most skillful men that we have, and as the work on walnuts done at the same time showed 100% success with a number of varieties, I think any question as to the skill with which the work was done and the care the grafted trees had afterwards can be dismissed.
It is to be regretted that the number of scions at hand was not sufficient to repeat exactly the experiments of 1923 as well as to follow out the points suggested by the 1923 work, but as there was not enough for both, the latter was done.
The 100% success of catches of the Barnes in 1923 was not repeated in 1924; but the high per cent of catches on the mockernut, (7 out of 8 in 1924), is gratifying in view of the few varieties that we have that have shown adaptability to that stock. As the Barnes is one of our good varieties and there is such a wide section of the country where the mockernut is the prevailing hickory, it is believed this behavior of the Barnes will prove a valuable addition to our knowledge in top-working the hickory.
No variety as strikingly adapted for use on the pignut has appeared, but there are a number that have shown fair adaptability.
The varieties most desirable for top-working various species of hickories as suggested by this work supplemented by other observations of the writer, would be as follows:
Shagbark—Most varieties.
Mockernut—Barnes.
Pignut—Brooks, Kentucky, Taylor, Kirtland.
Bitternut—Beaver, Fairbanks, Laney, Siers.
It is useful to know that the Barnes is the only one especially successful on the Mockernut. By the spring of 1924, all grafts on mockernut had died except the Barnes, the Gobble and the Long Beach, and each of these is thought to have mockernut parentage.
In the cases of the pignut and the pecan stocks, all of the grafts successful in 1923 were still living in 1924. With the shagbark and bitternut most lived. As to pecans there is not much to be said; pecan varieties would usually be used for the topworking here.
The results of a few grafts set in 1924 on Carya ovalis and on shellbark seedlings which were 100% failures, are not noted, as the shellbarks were, in the judgment of the writer, too small for the purpose, and the Carya ovalis had been set out in the spring of 1924 but a few weeks before the grafting was done. In other words the latter had not become sufficiently established to make good stocks, and the former were not large enough. In each case there was not sufficient vitality available to expect success.
This brings out one point which has impressed me strongly; that is the need of having vigorous stocks if they are to be grafted or transplanted successfully. I feel that this point cannot be too strongly emphasized. If a stock either from youthfulness or inherent lack of vigor is not rapid growing it is almost useless to try to graft it or transplant it until it does show the needed vigor.