INTRODUCTION 



Estimates of tree volume, based on diameter, height, and species, provide the 

 foundation for many forestry practices. Recent interest in volumes of forest residues, 

 rapidly changing utilization practices, and an accelerated need to manage second-growth 

 stands of timber have created a demand for tables that indicate not only the volume of 

 wood in the merchantable part of a stem, but also the volumes of wood and bark in the 

 nonmerchantable parts, and in stems smaller than the prevailing merchantability standard. 



The accompanying tables (appendix) have been prepared mainly for the purpose of 

 predicting stem residue volumes that may result from thinning or harvesting. The trees 

 selected for the study do not exceed 80 years of age, and so may represent stem devel- 

 opment in unmanaged second-growth stands. Minimum tree diameter is 1-1/2 inches d.b.h. 

 (o.b.) and the maximum diameter varies by species, given the constraints of age and 

 growing site. The sample trees were obtained from selected stands on both public and 

 private lands in western Montana and include a broad range of growing conditions. Only 

 dominant and codominant trees were measured, and no trees were selected that showed, 

 from ring examination, marked periods of suppression. 



METHOD OF STEM MEASUREMENT 



All measurements were made on felled trees as shown in figure 1. The total height 

 and d.b.h. (o.b.) of each tree were determined first. To eliminate the problems of 

 disproportionate measure in using a fixed bolt length, the tree was then divided into 

 six segments of equal length for further measurement. A diameter tape was used to 

 measure diameter outside bark at the base of each segment. Bark thickness at the base 

 of each segment was measured using a Swedish bark gage. At thick-barked section the 

 bark gage measurement was augmented with an axe cut, the thickness then measured with 

 an engineer's scale. A minimum of three bark-thickness measurements were made at the 

 base of each segment and the average value was determined. An additional measurement, 

 inside bark, was made at an assumed stump height of 1 foot above the average ground 

 level. All diameter and bark-thickness measurements were recorded to the nearest tenth 

 of an inch. Total tree height was measured to the nearest foot. The segment lengths 

 were converted to inches and measured to the nearest inch. 



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