Much of this intelligence should be of the "green thumb" variety, a mixture of common sense and keen observation. The one using this kind of intelligence would plant black walnuts in a deep, rich, well-drained loam, because he has observed that this species grows best and yields more heavily in that type of soil. He would plant the trees with top roots not more than one inch under the surface of the soil because he has noted that is the way they grow naturally. He would strive to keep foliage on the tree as long as possible because he knows that the leaves are the manufacturing part of the tree. Without them the tree could not grow and would not produce filled nuts. He would do many other things essential for proper tree growth and yield. But unfortunately several of the farm nut tree plantings I have seen show a woeful lack of "green thumb" intelligence. I recall one in particular because of the condition of both the trees and the owner. The planting originally consisted of twenty Chinese chestnuts, fifteen named black walnuts, four hicans and four Persian walnuts. The owner originally was an enthusiastic convert to nut growing. Today the planting is a failure, while the owner is an irate backslider who would not plant another nut tree even though it bore ten dollar bills. Four years after planting, nineteen of the twenty chestnuts, all hican, three Persian walnuts and ten black walnuts were dead. Of the remaining seven trees only one could be called healthy. Examination soon focused the picture. Most of the trees had been planted on an eroded hillside deficient in humus. In addition, many of them were planted from three to ten inches too deep. The only thriving walnut was planted at the proper depth and in a pocket of top soil at the base of the slope. Under questioning, the owner said that he had purposely planted them deep to "keep their roots cool." That is a widely held horticultural fallacy which is unconsciously fostered by many nurseryman. In their instructions they say to plant the tree one inch deeper than it was in the nursery. Too many laymen reason that, if planting the tree one inch deeper will help, then the tree should do even better if planted six inches deeper. After eighteen years of trying to learn why transplanted trees do not thrive, I am convinced there are four main causes. I list them in the order of their prevalence. First and foremost, too deep planting. Second, fibrous roots allowed to become dry. This may occur in transit, in the hands of the purchaser or because of air space around the roots after planting. Third, deficiency of moisture due to low humus content of the soil or drought. Four, rodent damage. While some nut trees are possibly more difficult to re-establish than a few other species, if care is used to see that none of these four conditions occurs, there is no reason why a well-rooted tree should not grow and remain healthy.