inside-bark top. Volumes per acre were computed for each plot from 

 the initial data and the nine-year data. Periodic annual growth per acre 

 was computed as follows: 



(9 year volume) — (initial volume) 

 Periodic annual growth per acre = • 



Other variables were computed from the initial data. These con- 

 sisted of: 



(1) Mean breast-height age 



(2) Site index based on breast-height age 50 years 



(3) Basal area per acre for trees 3.0 inches d.b.h. and larger 



(4) Basal area per acre for trees 9.0 inches d.b.h. and larger 



(5) Mean stand total height based on dominant-codominant trees 



(6) Total live trees per acre 



(7) Mean Girard form class 



(8) Stocking percent as described by Leak et al. (1970) 



Stand Volume Tables 



Stand volumes can be predicted from variables that are easily 

 measured and are considered representative of the entire stand. Thus 

 a forester can predict stand volume per acre without determining vol- 

 umes of individual trees. This study provided adequate data to develop 

 regression equations for both cubic-foot and board-foot volume esti- 

 mates per acre. 



The dependent and independent variables were derived from the 

 plot data. Cubic-foot and board-foot volumes per acre were related to 

 basal area per acre, mean dominant-codominant stand height, and mean 

 Girard form class. Basal area per acre used in the cubic-foot volume 

 per acre regression was for trees 3.0 inches d.b.h. and larger. Basal 

 area per acre used in the board-foot volume per acre regression was for 

 trees 9.0 inches d.b.h. and larger. 



The model for estimating cubic and board foot volume per acre 

 was: 



Logio (Volume per Acre) ^ 



bo + bi (Logio BA) + bo <LogioH) + bs (LogioGFC) + e Model 2 



where: BA = basal area per acre 



H ^ mean stand height of dominant-codominant trees 

 GFC = mean Girard form class 

 e = error 



This model was based on variables described by Bruce and Schu- 

 macher (1950) for predicting volume per acre. 



For cubic-foot volume per acre the regression solution to Model 2 

 was: 



Log 10 (Cubic-foot volume per acre) = 



—1.836 + 1.042 (LogioBA) + .387 (LogioH) + 1.324 (Log loGFC) 

 where: Coefficient of determination (R-) = .958 

 Standard error = .84% 



The solution to the cubic foot volume per acre equation is shown 

 in Table 4. 



