on estimating aboveground weights of tree stands

Abstract

Simulated sampling of nine tree stands was used to compare estimated stand component weights with known weights based on complete harvest. On average, estimates based on regressions of logarithm weight on either logarithm tree diameter or on logarithm (diameter)2 x height overestimated weights of stems, branches, and leaves by - 3% when the inherent bias of such regressions was accounted for. Ninety-five percent confidence intervals based on random sampling encompassed the measured stand weights 79%-100% of the time. Similar confidence intervals using stratified random sampling based on tree diameter encompassed the measured stand weights only 44%-98% of the time. The small average bias in estimates of stand weight using logarithmic regressions is of minor importance compared with the variation in estimates among replicated samples.