SYLVICULTURE. 



Ivnormous seeding capacity and sprouting capacity. Average di- 

 ameter 20 feet, height 275 feet, age up to 4,000 years. 



III. Pacific forest of moderately cold zone. 



This zone is economically of no importance, although it is the 

 forest zone proper, owing to the impossibility of agriculture within 

 this zone. It is " The Canadian Forest Zone." It lies in the Sierras 

 at 8,000 feet, in the Cascades at 4,000 feet, and in Alaska at seashore. 

 The forests of the Xorthern Rocky mountains belong to it preferably. 



Pinus murrayana (Lodgepole Pine). Shade bearing, in close 

 stands, very branchy, very sappy, retaining cones, easily destroyed 

 by fire, closely related to the Jack Pine of the east. Frequent on 

 old burns, typical for Yellowstone Park, going south to Arizona. 



Larix occidentalis (Western Tamarack). Splendid lumber tree, 

 often in pure forests, optimum in Montana, natural regeneration 

 easy, rapid height growth, little sap wood, timber equal to Long 

 Leaf Pine. 



Pinus flexilis (Limber White Pine). More branchy and much 

 shorter than eastern White Pine; forms open forests on south slopes 

 of Sierras and in Nevada at 7,000 feet elevation; from Montana it 

 extends southward to Colorado. 



Pinus monticola (Mountain White Pine). In Cascades, British 

 Columbia, Idaho, Montana, in the latter state more on slopes drain- 

 ing westward. ' 



Abies nobelis, amabilis, magnifica, the Red Firs of the west. 

 Magnifica know y n in California as Larch. The two first named often 

 associated with Abies grandis and more frequent in Washington and 

 Oregon than in California. Amabilis extends into Alaska. Red Firs 

 are lacking in the Rockies. Needles are dark. 



Picea engelmanni (White Spruce). At home in middle and 

 southern Rockies, on northern slopes at altitudes averaging 10,000 

 feet. 



Picea parryana (Colorado Blue Spruce). Needles very pointed 

 and stinging, of a bluish tint. Occupies moist ground. 



IV. Pacific forest of the Alpine region. 

 Typical trees are: 



Pinus albicaulis (Dwarf White Pine). Occurring in the Cascades 

 and the Rockies (Utah). 



Pinus balfouriana and aristata (Fcx-Tail Pine). White Pine 

 found in California at 8,000 feet to 12,000 feet elevation; twigs thin, 

 retaining needles for many years. 



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