The adjusted diameter growth means for the individual stands within habitat 

 types had a large amount of variation (table 3) . The stand diameter growth means 

 in the Tshe/Pamy h.t., ranged from 1.62 to 7.05 inches (4.11 to 17.91 cm). In the 

 Psme/Caru-Aruv h.t., adjusted diameter growth means ranged from 1.29 to 6.60 inches 

 (3.28 to 16.76 cm). The stand diameter growth means in the other habitat types 

 showed similar variation. 



Height Growth 



As with diameter growth, height growth is also dependent upon tree size and age. 

 The 10-year height growth means were adjusted using covariance analysis for initial 

 height and age. The growth means by habitat type were then compared using SAS least 

 squares mean separation procedure. 



The Pipo/Syal h.t. had the smallest 10-year height growth mean, 4.02 ft (1.23 

 m) . The Thpl/Pamy h.t. had the largest height growth mean, 10 ft (3.05 m) (table 4). 

 Three habitat type groups were distinguished by height growth: (1) Pipo/Syal; (2) 

 Abla/Pamy, Pswe/Syal, Psme/Phma, Abgr/Pamy , Tshe/Pamy, Abla/Vasc; (3) Psme/Caru-Aruv, 

 Thpl/Pamy . 



Within each habitat type there is a wide range of height growth means. In the 

 Tshe/Pamy habitat type, lO-year adjusted height growth ranged from 2.54 ft (0.71 m) 

 to a maximum of 14.18 ft (4.32 m) . Likewise in the Abgr/Pamy habitat type, adjusted 

 height growth means ranged from 1.43 ft to 11.19 ft (0.44 to 3.41 m) . 



Stand Yields 



Individual tree height and diameter growth characteristics are of less consequence 

 to forest managers than stand growth characteristics. Therefore, we projected each 

 stand into the future using a prognosis model (Stage 1973) . This procedure produced 

 36 local yield tables, one for each of the stands in the study (appendix tables 5-40) . 



In reviewing the stand projections we feel most of them are realistic. These 

 projections may be used to estimate future volumes of stands of similar nature. 

 Enough information is provided so the forest manager may compare his stand conditions 

 and descriptions to those we have summarized. 



DISCUSSION 



A study of this type produces a large amount of information that can be used in 

 many ways. Si Iviculturists can predict future yields of stands they feel are 

 comparable. Timber management planners and researchers can use these data to refine 

 yield predictions. 



This study encompasses a large geographic area with many different sites. Even 

 within habitat types many different sites exist that are reflected in the mean 

 diameter and height growths. In relation to habitat types, we have shown a wide 

 range of growth on the same habitat type. Some areas and habitat types we expected 

 to have poor growth proved capable of excellent diameter and height growth, especially 

 on the central Montana forests. 



7 



