224 Forestry Quarterly. 



usually in open, park-like stands, preferably on north slopes with 

 Alpine Fir, Engelmann Spruce, Lyall Larch, Limber Pine and 

 Lodgepole Pine. On summits of Cascades, commonly pure at 

 timber line, and often in clusters of from 3 to 7 trees, as if grow- 

 ing from same root. In southern Washington, with Alpine Fir, 

 Black Hemlock, and Yellow Cedar; in Oregon with Black Hem- 

 lock, Alpine, Lowland, and Noble Firs, Lodgepole and Western 

 White Pine, and Engelmann Spruce. In the Sierras, forming 

 pure groups at timberline, on east, south, and west slopes, with 

 patches of Black Hemlock and Western White Pine, and at lower 

 altitudes with Lodgepole Pine." (Sudworth.) 



In Montana and Idaho, the species occurs sometimes in pure, 

 open stands on grassy areas, but usually in open park-like stands, 

 preferably on north slopes, in mixture with Alpine Fir, Engel- 

 mann Spruce, Lyall Larch, Lodgepole Pine, and in the Rocky 

 Mountains proper, with Limber Pine. In moist localities, it is 

 also found on southern and western exposures. In the dense 

 forests of northern Idaho and western Montana, competition is so 

 strong that the intolerant White-bark Pine is usually crowded 

 onto the highest pinnacles and most unfavorable situations, and 

 even there its occurrence may be limited to occasional specimens. 

 In the somewhat drier forests of central Idaho and central and 

 southern Montana, the struggle is not so severe, and the species 

 is apt to occur in considerable stands in favorable situations. 



White-bark Pine is always found in situations which undergo 

 great seasonal and daily ranges of temperature, and which are 

 subject to fierce winds, very heavy snows, and a short growing 

 season. 



Commercial Distribution in District I. — This species does not 

 approach a size and quality which would suit it for commercial 

 purposes, except when growing in the most favorable situations, 

 such as on deep rich fairly moist soils in protected spots. Super- 

 visor J. E. Barton mentions only one locality on the Pend Oreille 

 Forest where it exists of merchantable size over considerable 

 areas. In the vicinity of Lake Darling, at an elevation of 5,000 

 feet, it occurs in rather dense groves of considerable extent, 

 forming a fringe on the alpine meadows surrounding the lake. 

 This basin is protected by ridges running up to 1800 feet above 

 the lake. No groves of importance are recorded on the Kaniksu 

 or the Coeur d'Alene, but on the Clearwater and Nezperce 



