Table I . --Removal factors by Forest Survey standards to estimate total net removals 

 from inventory y western South Dakota^ Wyoming^ Utah, and Colorado 



Unit of measurement : 

 and : 

 minimum top diameter : 



South Dakota 



Wyoming 



: Utah 



: Colorado 



Cubic foot 

 4 inches 



h.038 



1.070 



1.068 



1. 100 



Board foot 

 variable 



.997 



.933 



.974 



1.035 



Board foot 

 7 inches 



.984 



.929 



.973 



1.035 



^ For example: 1.038 x 7,352 MCF of saw logs harvested in western South Dakota 

 in 1969 = 7,631 MCF total net removals by Forest Survey standards. 



in the net board-foot scale. This wood is (a) in the upper stem portion beyond the 

 minimum top diameter for board-foot measure; (b) in destroyed growing stock trees of 

 less than sawtimber size; and (c) in portions of trees suitable for production of 

 fiber but is cull for saw logs because of crook. 



Board-foot measurements to the minimum variable top used by Forest Survey do not 

 result in factors much different from those resulting from the minimum fixed top of 

 7 inches. 



Logging Residues as a Percent of Product Volume 



The net volume of logging residues represents underutilization. By Forest 

 Survey's cubic-foot standards, residues include all unused net volume between a 1-foot 

 stump and a 4-inch minimum top diameter inside bark (d.i.b.). By board-foot standards, 

 net residues volume includes unused wood in sawtimber trees between a 1-foot stump to 

 either variable or fixed top diameter (fig. 2). Also included in sawtimber residues 

 are merchantable logs missed in skidding. 



Most of the residue volume is caused by felling and is wood from the trees from 

 which saw logs are harvested. Skidding losses are relatively minor and, as shown in 

 table 2, amount to less than 25 percent of the cubic-foot residue volume in each of 

 the four States. 



The net volume of logging residues resulting from harvesting a reported volume of 

 saw logs can be estimated using the percentages in table 3; the figures in this table 

 are not adjusted for overutilization. Their use provides an estimate of actual re- 

 sidues (table 4) without the partial compensation of overutilization volumes, such as 

 can be obtained by using table 1 factors. Residue volumes derived using the percent- 

 ages in table 3 should not, of course, be considered as a measure of economically 

 available chippable wood. The study was not designed to provide this information. 



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