The nuts from these crosses were stratified in sand in a cold frame, dug up, and planted in the greenhouse in early March. After one transplanting they were moved to the nursery to grow for two years, when they were moved to the seedling orchard. The nuts from one year's crosses were planted directly in the nursery but germination was low due to drought.
The seedlings were spaced 10 x 5 feet in the orchard. This spacing was satisfactory if the trees came into bearing the fourth year, but if unfavorable weather eliminated the first or second crops the trees became too crowded to permit satisfactory fruiting. Usually, however, the trees fruited sufficiently to make it possible to evaluate them and remove the inferior trees so that the better seedlings would have enough room to remain for several additional crops.
During the first few years the orchard was clean cultivated until cover crops were sown in August. In later years the orchards were not cultivated but nitrogen fertilization was substituted. Satisfactory growth was maintained, but the grass and weeds made harvesting more difficult. No pruning was done except at planting time as the seedlings were all evaluated before pruning was needed. Suckers were removed around the young trees, but as they became older this was not done and some of the plants now have several stems.
Evaluating the Seedlings
The nuts were harvested in the fall after they had dropped, or, with the later maturing seedlings and those which tended to cling to the tree, they were harvested by picking or shaking them from the tree. As soon as practicable the nuts were husked and the crop of each tree weighed and recorded. Samples of nuts of every seedling fruiting were placed on paper plates, each population being by itself, and eight or ten nuts of each sample were cracked and left on the plate. The seedlings were then divided into three classes, those that were obviously good, those that were poor, and an intermediate class that received further attention. The poor seedlings were marked for discard and if so marked for two or three years they were pulled out.
The good seedlings were then examined more carefully and sorted into three groups, as follows:
1. Those that were outstanding in both nut and tree characters.
2. Those that were good enough to propagate for a second test, but not equal to the best.
3. Seedlings good enough to keep for further observation. These were usually good in one or more characteristics but deficient or doubtful in one important feature. If upon further testing these third group plants proved to be outstandingly productive or hardy they were given a higher rating.
In examining the nuts, emphasis was placed on size and color of the nut, the large, bright brown nuts being considered more desirable than the smaller, duller colored, pubescent nuts. The amount of space between the shell and the kernel was important. If the kernel fitted tightly it was easily broken or chipped in cracking the nut. Thickness of shell was of minor importance as only a few were thick enough to make cracking difficult.