Fitting Taper Equations from Standing Trees

Abstract

Taper equations from standing trees were developed for 32 major groups of the commercial species of British Columbia by applying outside bark data to an accepted taper model (the Whole-Bole system). Tests of this model on all groups show that estimates of volume, diameters inside bark at different heights, and heights for different diameters are sufficiently accurate and precise for practical use. In some cases, standing tree estimates are more reliable than those produced from the inside bark taper equations currently used in British Columbia. Including a bark thickness prediction function in the model would improve the reliability of estimation.Taper data can be obtained from standing trees accurately and inexpensively with a Barr & Stroud dendrometer. Because of this method of data collection is more efficient than felled tree measurement, these standing tree taper equations have great potential for use in local situations and where nondestructive samples are required.