The Breithaupt Todis Dendrometer—An Analysis

Abstract

Abstract The Breithaupt Todis, a variable-base, fixed-convergence-angle dendrometer, is described and the results of tests for bias and precision are presented. No systematic bias was detected and upper-stem diameters can be measured within ±0.7 cm (0.28 inch) 95 percent of the time. The instrument can also be used to measure distance and height, and all measurements can be read in the field (in metric units). It should be useful for stand mapping and on sample plots when several trees need a number of measurements. It is not a good instrument to use for timber cruises covering large areas that only require a few measurements of a large number of trees.