DISCUSSION AND CONCLUSIONS 



A summary of the methodology for predicting the various volume types is given in 

 table 17. The advantage of this approach to developing volume equations is that it 

 avoids or eliminates many of the problems of consistency, compatibility, reliability, 

 and flexibility found with previous sets of volume equations. The disadvantage is that 

 the method does not lend itself well to hand computations of tree volumes. To minimize 

 this problem, we have prepared volume tables for unforked trees ("Comprehensive tree 

 volume equations for major species of New Mexico and Arizona: II. Tables for unforked 

 trees"). For those with access to a computer, a FORTRAN subroutine has been written 

 and can be obtained in versions for the CDC 6400 or the UNIVAC M.08 by writing: 



Southwest Volume Subroutine 

 Forest and Range Evaluation Unit 

 — . Intermountain Forest and Range Experiment Station 



507 - 25th Street 

 Ogden, Utah 84401 



Table 17. — Surmary of methodology for predicting various tree volume types 



Predicted value ' Method for prediction 



Total stem gross cubic foot volume, unforked trees 

 Total stem gross cubic foot volume, forked trees 

 Merchantable gross cubic foot volume, unforked trees 

 Merchantable gross cubic foot volume, forked trees 

 Gross International 1/4-inch board foot volume, unforked trees 

 Gross International 1/4-inch board foot volume, forked trees 

 Gross Scribner board foot volume, unforked trees 

 Gross Scribner board foot volume, forked trees 

 Total stem net cubic foot volume, unforked trees 

 Total stem net cubic foot volume, forked trees 

 MerchcintcLble net cubic foot volume, unforked trees 

 Merchantable net cubic foot volume, forked trees 

 Net International 1/4-inch board-foot volume, unforked trees 

 Net International 1/4-inch board foot volume, forked trees 

 Net Scribner board foot volume, unforked trees 

 Net Scribner board foot volume, forked trees 





















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