Equations for predicting the 5-year height growth of six conifer species in southwest Oregon

Equations for predicting individual-tree height growth per 5-year period are presented for Douglas-fir, white fir, grand fir, ponderosa pine, sugar pine, and incense-cedar growing in the mixed-conifer zone of southwest Oregon. The data used to develop the equations came from 3,648 trees sampled from 391 stands in the study area. Parameters were estimated by means of nonlinear regression. The model for height growth is expressed as a function of site index, total tree height, crown ratio, and percentage of crown closure at total height of the subject tree.