More practical critical height sampling.This article is part of a larger document. View the larger document here.
Critical Height Sampling (CHS) (Kitamura 1964) can be used to predict cubic volumes per acre without using volume tables or equations. The critical height is defined as the height at which the tree stem appears to be in borderline condition using the point-sampling angle gauge (e.g. prism). An estimate of cubic volume per acre can be obtained from multiplication of the sum of the critical heights at a sample point by the point sampling basal area factor. One of the most serious problems with practical implementation of critical height sampling is that trees near the sample point have a very high critical height, which can be difficult to view from the sample point.