Predicting Site Index and Height for Selected Tree Species of Northern Idaho

摘要

Forests in northern Idaho are capable of supporting as many as 10 different tree species on a given site. Comparing site indexes of species across a variety of sites is one method of assessing which species to favor in stand management. From plots across the spectrum of forest environments, site indexes (50-year index age) of species pairs (26 combinations of a possible 36 total combinations for nine species) were shown by regression analysis to be linearly related. Site index values of one species were able to explain between 33 and 85 percent of the variation in the site index of associated species. Because land managers are interested in more than comparative heights at an arbitrary index age, the authors developed equations for predicting the height of species A from the predictor variables, site index of associated species, and the age of species A.