Remeasuring tree heights on permanent plots using rectangular coordinates and one angle per tree

Abstract

Heights of permanent sample trees with tops visible from any point can be measured from that point with any clinometer, measuring one vertical angle per tree. Two horizontal angles and one additional vertical angle per observation point are necessary to orient the point to the plot. Permanently recorded coordinates and elevations of tree locations are used with the angles to calculate the instrument location and elevation, instrument-to-tree distance, and total tree height. The method is efficient only if a programmable calculator or a computer can be used for calculations. Procedures and formulas are suggested, including formulas for calculating the coordinates of tree locations in a plantation plot from tree identification numbers. Error relationships are discussed. Applications are suggested and one test is described.

Citation

Neal, R.L., Jr. 1973. Remeasuring tree heights on permanent plots using rectangular coordinates and one angle per tree. Forest Science. 19(3): 233-236.