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Abstract
Individuality in man is accepted without question. In domestic animals, also, good and bad individuals are generally recognized. Even in some cultivated plants —orange trees and rubber trees— the poor producers are searched out and eliminated. Indeed, individual variability is a normal condition in all groups of organisms. Yet forest trees are rarely thought of in terms of the individual. Forest products are seldom of sufficient value to justify tending the individual tree. But there is no more reason why two western yellow pine trees should grow with equal rapidity or bear equal amounts of seed because they grow under identical conditions than that two men should attain equal strength or equal mentality because they receive the same food. When to inherent variability are added the effects of a wide range of interrelated environmental factors, the great differences in the behavior of individual trees can be readily appreciated. It is adjudged a common fault to lose sight of the forest through confusion of the trees. Much more frequently in forestry the mass effect is the more obvious, and there is failure to see in their proper relationships the elementary components of the. forest—the individual trees.
Citation
Dunning, Duncan. 1928. A tree classification for the selection forests of the Sierra Nevada. Journal of Agricultural Research. 36(9): 755-771.