Site index and height growth curves for unmanaged even-aged stands of western hemlock and sitka spruce in southeast Alaska /

Abstract

Site index and height growth curves and equations for unmanaged even-aged stands of western hemlock (Tsuga heterophylla) (Raf.) Sarg.) and Sitka spruce (Picea sitchensis (Bong.) Carr.) were derived from stem analysis of data from tree stems on 91 plots in southeast Alaska. Site index curves can provide estimates of site index for unmanaged stands if total height and age at breast height are known. Height growth curves can provide estimates of total height if site index and age at breast height are known. The curves are based on measurements of total height and age at breast height for hemlock or spruce on 1/5-acre plots in southeast Alaska. Sample trees were selected in even-aged stands from among trees containing no visible evidence of past attack by insect or disease and having a diameter at breast height near the quadratic mean diameter of the eight largest diameter hemlock and spruce on the plot.