Total Stem Gross Cubic Foot Volume — Unforked Trees 



The total stem gross cubic foot volume of unforked trees is predicted from the 

 model : 



= ao + aiD^H 



where 



V, = Predicted total stem gross cubic foot volume of an unforked tree 

 D = Diameter at breast height (d.b.h.) in inches 

 H = Total tree height in feet. 



The sp-NF specific, weighted least squares regression coefficients, and aj, are found 

 in table 2, along with the number of trees used in their development and the resulting 

 RMSQR. Methodological details can be found in appendix I. 



Table 2. — Unforked tree total stem gross auhia foot volume data base and regression results 

 I 



Species 



: National 

 Forest 



Number 

 of 

 trees 



Regression 



coefficients 



: Relative 

 :mean squared 

 : residual 

 : (RMSQR) 















White pine 



Lincoln, Santa Fe, Carson 



43 



0.160888987 



0.00203250045 



0.0177 



Engelmann spruce-corkbark fir 



Lincoln, Santa Fe, Carson 



155 



.225466084 



.00216969983 



.0329 



Yellow pine 



Coconino, Tonto, Lincoln, 

 Santa Fe, Carson 



201 



.237204154 



.00221122919 



.0292 



Blackjack pine 



Coconino, Tonto, Lincoln 



680 



.0810724804 



.00198351037 



.0266 



Blackjack pine 



Santa Fe, Carson 



220 



.0483082948 



.00204968419 



.0435 



Douglas-fir 



Lincoln, Tonto 



108 



.438373815 



.00175642739 



.0162 



Douglas-fir 



Santa Fe , Carson 



81 



.341133398 



.00191796994 



.0368 



Aspen 



Scinta Fe , Carson 



109 



.0327 



.00231123522 



.0199 



White fir 



Lincoln 



43 



.210903832 



.00183995833 



.0213 



White fir 



Santa Fe, Carson 



58 



.157776859 



.00200912252 



.0277 



5 



