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FOREST UTILIZATION INDUSTRIAL FORESTRY 



prove the forest for the future. It embodies the very essence of for- 

 estry principles as applied to standing merchantable timber. It satis- 

 fies both present and future requirements in forest management. It is 

 constructive, as contrasted with former destructive methods of forest 

 exploitation. 



On logging operations, only those trees are cut which will yield an 

 immediate cash return. Formerly there was little if any scientific 

 determination of what size trees would turn out profitable when logged, 



FIG. 84. A selectively logged area of ponderosa pine in the Bitteroot National 

 Forest, Montana. Stumps were cut low, brush and logging debris carefully piled 

 and burned and close utilization of the tops was practiced. The remaining 

 thrifty trees grew much more rapidly when the canopy crowding was released. 

 Trees were generally cut to a flexible diameter limit of about 19". 



manufactured, graded, and seasoned. The question of selectivity may 

 apply to individual trees, groups, or areas. It is a combined silvi- 

 cultural and utilization measure, although its objectives are primarily 

 of utilization. On National and other public forests, it serves both 

 purposes. It has been unintentionally practiced in a crude and unsci- 

 entific manner for many years on farmers' woodlots throughout the 

 East and on many private operations. It recognizes the established 

 fact that logging costs per thousand board feet increase with decreas- 



