SYLVICULTURE. 



I'.'normous seeding capacity and sprouting capacity. Average di- 

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



IIL Pacific forest of moderately cold zone. 



Tliis 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 Northern Rocky mountains belong to it preferably. 



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

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

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

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



Larix oecidentalis (Western Tamarack). Splendid lumber tree, 

 often in pure forests, optimum in Montana, natural regeneration 

 easy, rapid height growth, little sap wood, timber equal to L<mg 

 Leaf Pine. 



Pinus flexilis (Limber ^'Vliite Pine). More branchy and much 

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

 of Sierras and in Xevada at 7,000 feet elevation: from ilontana it 

 extends southward to Colorado. 



Pirius monticola (Mountain '\Miite Pine). In Cascades, British 

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

 ing westward. 



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

 Magnifica knoAvn in California as Larch. The two first named often 

 associated with Abies grandis and more frequent in Washington and 

 Oregon t,han in California. Amabilis extends into Alaska. Red Firs 

 are lacking in the Rockies. Xeedles are dark. 



Picea engelmanni CWliite Spruce). At home in middle and 

 southei'n 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 albicaiilis (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 id 12,000 feet elevation: twigs tliin, 

 retaining needles for many years. 



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