7. There are a few seedlings that are single stem upright trees (no old stump in evidence) that reach up to 20 and rarely 25 or 30 feet in height with a diameter of 6" or so.
(Mr. R. B. Clapper thinks it is probably due to the absence of an old, infected stump that this greater height is reached.)
8. Ringing by the blight does not necessarily force the flowers and nuts. The woodlands abound with chestnut sprouts in all stages of girdling without pollen or fruit.
When I have my trees in bearing, I will be glad to furnish pollen and nuts from them to anyone that pursues the important work of trying to improve what I consider the most promising nut tree we yet know.
Winter Injury to Nut Trees at Ithaca, New York, in the Fall and Winter of 1947-48
L. H. MacDANIELS and DAMON BOYNTON, Ithaca, N. Y.
The winter of 1947-48 caused more damage to nut trees at Ithaca, New York, than any since 1933-34. It was a combination of a series of early freezes followed by sub-zero temperature in mid-winter. Apparently the most injury was done by the fall freezes. These occurred on September 25, 26, and 27. On each successive night the temperature dropped lower than the preceding, and on September 27 was around 20°F. There was considerable variation in temperature related to exposure, air drainage conditions, and other factors.
On West Hill in Ithaca the minimum temperature recorded on September 27 was 23°F. Injury to leaves and nuts was severe. Within a few days the leaves had shrivelled and dried on the trees. It was apparent that this early freeze came before the abscission layers were formed in the leaf bases or growth matured. Ordinarily, a hard freeze late in the season will cause the trees to drop the leaves the next day. The nuts on the trees were frozen solid and mostly turned black within a few days and began to shrivel. Development was stopped, with the result that the nuts on all varieties were very poorly filled. The cavities appeared on first cracking to be full of kernel, but on drying these shrunk so that they were practically valueless. Some of the nuts were planted in a nursery row in the fall and germinated fairly early, showing viable embryos in spite of arrested development.
During the winter the temperature fell to -25°F, a temperature which ordinarily would not damage black walnuts seriously. It is impossible to separate the effect of the low winter temperatures from that of the early freeze in September. In this location the net result of the early freeze and the severe winter was to kill vigorously growing grafts on the walnut trees. Also the cambium in the main crotches of a Stambaugh tree with a trunk about 14 inches in diameter was killed. This tree was destroyed in a windstorm in August, 1948, but it is not clear that the breakage was related to the winter killing in 1947-48. None of the trees now has a good crop, which may be or may not be related to the frost in the fall. It is entirely possible that failure to form blossom buds is caused either by killing of bud primordia or more likely by depletion of carbohydrate reserves due to the loss of leaves in early fall.
One seedling of Carpathian walnut was not damaged seriously except for some slight terminal twig killing. Another tree, however, had most of the smaller branches killed. Hickories and chestnuts were apparently not seriously damaged but some seedlings of the Japanese walnut were killed to the ground.