IMPLEMENTATION OF 

 THE MODEL FOR LODGEPOLE PINE 



Lodgepole pine was the first forest type for which this growth prognosis model was 

 implemented. This species was selected because it characteristically grows in pure, 

 even-aged stands so that the development of the necessary component models would be 

 simpler than would be the case for mixed stands. Data on diameter- growth rates were 

 available for a wide range of stand densities from studies installed as part of the 

 Intermountain Station's silvicultural research on lodgepole pine. In addition, many 

 lodgepole pine stands had been sampled in the course of the normal timber management 

 plsmning inventories conducted by the Northern Region. Interregional site curves that 

 include adjustments for stand density had been recently derived for this species 

 (Alexander, Tackle, and Dahms 1967) . In addition, a stand density study of lodgepole 

 pine with very detailed data on crown development was also in progress in the silvi- 

 cultural research project of the Pacific Northwest Station, Bend, Oregon (Dahms 1967). 

 Lodgepole pine is not a particularly good forest type to demonstrate the full utility 

 of the approach used in this growth prognosis program. Stand growth models such as 

 developed for this species by Myers (1967) at the Rocky Mountain Station would be ade- 

 quate for most purposes. However, stand growth models do not seem to be adequate for 

 forest types of highly variable species composition or highly variable age class compo- 

 sition. Nor do stand growth models offer as much flexibility for comparing alternative 

 silvicultural prescriptions as is possible with models treating individual tree records. 

 Also, though the procedure may be overly detailed for a simple type such as lodgepole 

 pine, the purposes for which this model has been developed would best be met by a 

 unified approach applicable to all species and types. 



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