Components of juvenile-mature correlations in forest trees.

Juvenile-mature correlation has played an important role in indirect selection for size traits in forest trees. The juvenile size of a tree is a part of the mature size, and the juvenile-mature correlation is an example of a "part-whole" type of correlation. As is the case with any other "part-whole" type of correlation, the juvenile-mature correlation can be subdivided into two components; one is a function of variance only, and the other a function of variance and covariance. In this paper the components of the juvenile-mature correlation is described, the basic properties and the dynamics of its components analyzed, and the role of these components in explaining the gain from indirect juvenile selection discussed. Six forest tree populations were used to review the various properties of the model. The most important applied conclusions were: (1) even if two populations have the same juvenile-mature correlations, different selection strategies can be used depending on the nature of correlation components. (2) Choosing the proper mature age is as important as choosing juvenile age. (3) Understanding the growth curves of mean and variance is essential to developing selection strategies.