Mortality 



A regression model using mortality, in terms of number of stems 

 per acre per year, as a dependent variable and using functions of three 

 variables: total live stems per acre, mean age (breast-height), and site 

 index was developed as follows: 



TS 1 



Mortality = bo + bi ( \ ) + b2 (TS) + ba (-^) + b* (SI) + e Model 6 



A A 



where: TS = total live stems per acre 



A = mean age (breast height) 

 SI = site index 

 e =-. error 



The regression solution to Model 6 was: 



Mortality = —15.73 + .646 ( ^ ) + .0223 (TS) — 438.2 (-7-) + .257 (SJ) 



A A 



where: Coefficient of determination (R^) = .987 

 Standard error = 31.12% 



All variables in this equation were significant. The solution to the 

 equation is shown in Table 10. Mortality increases with increasing age, 

 site index, and total stems per acre. Most of the mortality occurs in 

 the suppressed-intermediate trees. 



21 



