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Mesavage and Girard form class taper functions derived from profile equations

Informally Refereed

Abstract

The Mesavage and Girard (1946) average upper-log taper tables remain a favorite way of estimating tree bole volume because they only require the measurement of merchantable (useable) height to an indefinite top diameter limit. For the direct application of profile equations, height must be measured to a definite top diameter limit, and this makes the collection of data more arduous, particularly in hardwoods, since in many cases both the height to the top diameter limit (stopper top) and the stopper top diameter must be measured. In this paper, Girard form class is used to convert a regular profile function into a Mesavage and Girard type taper model requiring only the measurement of merchantable height. The advantages of the new approach include: 1) the derived model’s upper log tapers are species specific, 2) the model describes the taper in the butt log, and 3) pulpwood and sawtimber trees can use the same model and height measure. Like the Mesavage and Girard taper tables, the converted profile equations have the disadvantage of requiring an average form class, preferably by dbh class. The source code for the profile conversion algorithm in C++, or BA SIC can be downloaded from www.timbercruise.com, www.cfr.msstate.edu, or by contacting the authors. The program is short and can be quickly embedded in any cruise program implementing profile functions.

Parent Publication

Citation

Matney, Thomas g.; Schultz, Emily B. 2007. Mesavage and Girard form class taper functions derived from profile equations. e-Gen. Tech. Rep. SRS–101. U.S. Department of Agriculture, Forest Service, Southern Research Station: 77-85 [CD-ROM].
https://www.fs.usda.gov/research/treesearch/27755