A comparison of competition measures and growth models for predicting plantation red pine diameter and height growth.

Several mathematical models for survivor tree growth were fitted, via nonlinear regression, to data from 17 permanent sample plots located in Pinus resinosa plantations in Wisconsin. Simple empirical models provided slightly better fits for diameter growth, and much better fits for height growth than did semi-empirical or constrained model forms. A considerable improvement in diameter growth model fit was obtained by including a measure of competitive stress (competition index), although it made little difference if intertree distances were incorporated in the index. The best fit was obtained by simply using sample plot basal area as the measure of competitive stress.-from Authors