Table 13. — Fraction autl in merchantable cubic foot volume ^ given 

 the tree is unsound^ data base, and regression results 



Independent varia±)les 



D = D.b.h. in inches 



m 



= Top diameter, inside bark, in inches 



H = Total tree height in feet 



Species, National Forest, and regression equations 



Number 

 of 



"observations 



Relative 

 :mean squared 

 residual 

 (RMSQR) 



White pine on Santa Fe , Carson, and Lincoln 



h = 0.525456732 



m 



j\ = -7.62194840E-04 - 1.72E-10D'' 



or '■ m 



FC = 0.139967204 + 1 . 40417133E-07D^ 

 m m 



Engelmann spruce on Santa Fe, Carson, and Lincoln 



h = 0.809722162 



m 



204 



0.8386 



Y„ = Jo + JiH + J^D^ 

 Jn = -4.79663334E-01 



246 



.8881 



<7l 



= 5.99578762E-03 



J„ = -3.54716909E-04 - 2 . 30591722E-05D 



or 2 m 



FC = 1.10092261E-01 + 4 . 70167336E-04D'* 



m m 



-8.80762813E-05D^ + 4 . 83607897E-07D^ 



m m 



Corkbark fir on Santa Fe and Carson 



h = 0.945856475 



m 



+ JiH/D 



120 



,8010 



or 



m 



m 



j'o = -2.04082904E-02 + 4 . 51477415E-02D 



j\ = -1.16845115E-02 - 1 . 29460840E-02D 



FC = 7.39331940E-02 + 6 . 95210968E-03D 

 m m 



Yellow pine on Lincoln, Coconino, Tonto, Santa Fe, 



and Carson 



h ='0.912935298 



m 



Jn = -1.67513064E-01 - 2.39E-07D^ 



924 



,9696 



or 



Jl = 3.368982527E-05 + 8.684E-11D 



m 



FC = 9.41334189E-02 + 4 . 35158264E-06D'' 



m m 



Blackjack pine on Lincoln, Coconino, and Tonto 



h = 0.294142214 



m 



JO = -3.39989415E-02 + 1 . 48516345E-04d2 



475 



,9351 



or 



= -2.19796372E-06 - 8 . 55224950E-09d2 



Jl 



FC = 1.92501222E-02 



m 



m 



, con . 



20 



