Energy Values for Whole Trees and Crowns of Selected Species

摘要

Energy values, Btu's (British thermal units) per ovendry pound, were determined for whole-tree crown materials from western hemlock (Tsuga heterophylla), coast Douglas-fir (Pseudotsuga menziesii), and western redcedar (Thuja plicata). Samples were collected from small diameter stands in northwest Washington where whole-tree harvesting is underway. Samples of crown material representing each diameter class were composited into a single sample for each species. Results of the study indicate that use of wood energy values may underestimate the product potential of hog fuel created from whole-tree chipping.