Estimating Douglas-fir site quality from aerial photographs.

Abstract

This study investigated the feasibility of developing a technique for estimating site index of Douglas-fir in the Pacific Northwest, using aerial photos and topographic maps. Physiographic features were used as indicators of site index. Analysis showed that although most of the features were highly significant as criteria for predicting site index, they explained less than one-third of its variation. Equations, using the physiographic features as independent variables, were shown to be useful for estimating site index by a double-sampling procedure--particularly in relatively inaccessible places. As a pioneer study, this paper points the way for further productive research in this field.

Citation

Choate, Grover A. 1961. Estimating Douglas-fir site quality from aerial photographs. USDA Forest Service PNW Old Series Research Paper No. 45: 1-26