174 FOREST DISTKIBXJTIOX 



laich and Douglas spruce on northern slopes to the marked 

 Pacific Coast Humid Transition of the northwestern valleys 

 ^here the strongest mesophytic conditions of the region prevail. 

 The main body of the forests on the mountain sides belongs to the 

 Canadian zone and consists largely of lodgepole pine, spruce, 

 larch, whitebark pine and alpine fir. The Hudsonian Zone is 

 nowhere clearly delimited from the Canadian and most of its 

 species make up a large part of the forests between 5.000 and 

 10,000 feet. However, at the higher elevations the alpine fir, 

 Engekaann spruce, and whitebark pine are the principal trees, 

 though of inferior size and form owing to the severe conditions 

 there found. 



