Crown. Non-spreading, spire-shaped, generally reaching almost 

 to the ground. 



Tolerance. Tolerant; about the same as Engelmann spruce. 



Reproduction. Seeds each year; heavily every three years; 

 begins at 20 years. Cones mature in one season and shed the seeds in the 

 early fall. Seeds large and winged; germination precent high; vitality 

 transient. Germinates well on duff or mineral soil. 



Range. Alaska to southern Arizona and New Mexico, and from 

 the mountains of the Pacific coast to the Rockies; leaves the coast in 

 Oregon and does not occur in California. From sea-level to 3000 or 4000 

 feet in Alaska, but is in general a timber line tree; up to 12,000 feet in the 

 Rocky Mountains. 



Climate. Severe. 



Soil. Widely adapted; from swampy to poor, thin, dry soils. Less 

 exacting as to soil moisture than Engelmann spruce. Does not thrive 

 on heavy dry soils. 



Association. Occurs in small pure stands at high altitudes, and in 

 mixture with black hemlock, Engelmann spruce, yellow cedar, white 

 bark pine, and amabilis fir. 



General. Commercial importance is small ; may be used for pulp- 

 wood some day, but at present it is inaccessible. It is of value as a pro- 

 tection forest. 



THUJA, The Cedars or Arborvit^s. 



Growth. Slow but persistent. 



Bole. Very tapering; often swell butted. 



Tolerance. Very tolerant. 



Wood. Soft, light, weak, very durable. 



Range. Middle Temperate Zone of North America and Asia. 



Soil. Generally inhabit wet places but can grow on dry soil. 



Association. Commonly grouped in mixture. 



General. There are 4 species of which two are in both the United 

 States and Canada. Its commercial importance is great. In Canada in 

 1912, cedars ranked fifth with 3.6% of the total lumber cut at an average 

 price of $17.98 per thousand. Of the total shingle cut of 1.57 billion, 

 91% were cedar at an average mill price of $2.00 per thousand. Of the 



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