An analysis of methods for the selection of trees from wild stands

Abstract

The commonly applied comparison-tree method of selection is analyzed as a form of within-family selection. If environmental variarion among comparison- and select-tree groups, c², is a relatively small proportion (17 percent or less with 5 comparison trees) of the total variation, comparison-tree selection will result in less genetic improvement than individual-tree selection, Even if c² is large, individual-tree selection may be more effective than comparison-tree selection if comparison and candidate trees are related. Estimates of c² and of relationships among trees in wild stands derived mainly from published reports suggest that comparison-tree selection may in fact result in less genetic gain than individual-tree selection in many tree species. In any case, comparison-tree selection will seldom be much more effective than individual-tree selection. Development of allernate techniques for applying cite corrections in the selection of superior trees is suggested.

Citation

Ledig, F. Thomas. 1976. An analysis of methods for the selection of trees from wild stands. Forest Science 20(1):2-16