FOREST TREES OF THE PACIFIC SLOPE. 83 



saw timber, the large percentage of clear, straight-grained wood making it very 

 useful and important commercially. 



Longevity. — A very long-lived tree. It grows rapidly in height in moderately 

 dense stands, and it grows very rapidly in diameter for several centuries when 

 alone or in an open forest. Large trees attain an age of from 400 to 750 years; 

 such trees are from 4 to 6 feet in diameter and from 150 to ISO feet high. About 

 800 or 850 years is probably the age of some of the much larger trees occasion- 

 ally met. Further study of its longevity is desirable. 



RANGE. 



Generally from sea level to S,000 feet elevation in coast region (and inland about 

 50 miles) from Alaska to northern California. 



Alaska. — Islands and sea slope of Coast Range from sea level to timberline (which 

 in the Panhandle, is 1,800 to 2,400 feet and 3,500 feet on exposed sea slopes) and 

 westward to west shore of Cook Inlet and north end of Kodiak Island. At Lynn 

 Canal extending up to 2,600 feet (limit of erect tree growth) ; west of Lynn Canal, 

 extending from sea level to 2,200 feet. From Dry Bay to Prince William Sound at 

 400 to 1,600 feet, and on Prince William Sound, from about 300 feet, in gulches away 

 from coast to over 1,450 feet on slopes facing the sound. In the interior of Kenai 

 peninsula to an elevation of 1,500 feet. Extends around Kenai peninsula, along shores 

 of Cook Inlet and Turnagain Arm, down west side of Cook Inlet — here scattered on 

 lower shore and southward, in sheltered places, to Kukak Bay at bottom of Alaskan 

 peninsula. Occurs similarly also in northern part of Kodiak Island, as far south as 

 Ugak Bay, on east shore, and to Cape Uganuk, on west shore. 



British Columbia. — Islands and vicinity of coast, on western slopes of Coast Range, 

 from about 3,000 to 4,000 or exceptionally to 5,000 feet ; summit between Cold- 

 water and Coquihalla rivers, to 3,280 feet; on Nicolume River, a few miles beyond the 

 summit between that stream and Sumallow River ; on the west side of Spioos River, near 

 the trail crossing, and up, again, to 5,000 feet, at Taku Pass. On west coast of Van- 

 couver Island, in Renfrew District, occurs up to 975 feet. 



WASHINGTON. Mainly at mouths of rivers and on bottomlands about Puget Sound 

 and along the Pacific coast ; also extending up valleys to the foothills of Cascades, 

 sometimes to an elevation of 2,000 feet. In (West) Washington National Forest, scat- 

 tered over river bottoms and benches below 2,000 feet; on Mount Viero (Whatcom 

 County) ; in Mount Rainier National Forest, only on Nisqually River, at 1,800 feet ; 

 at Orting (near Voights Creek) ; in Olympic National Forest, only on Pacific coast and 

 extending inland about 30 miles; in Soleduc Valley (at point 3 miles below Hot Springs) ; 

 at a point 2j miles south of Port Crescent, and at Elma, near Iloquiam River. 



Oregon. — In northern part, along the coast and up valleys to foothills of Cascades; 

 south of Columbia River Valley, confined to coast. 



California. — At mouths of streams and in low valleys facing the ocean as far south 

 as Caspar, Mendocino County. 



OCCURRENCE. 



Mainly from sea level to 3,000 feet; altitudinal range determined chiefly by soil and 

 atmospheric moisture. Contrary to habit of other trees of this region, which go to 

 lower elevations at north, this spruce reaches higher elevations at north than at south. 

 Generally in moist, coast alluvial and sandy bottoms, along streams, and especially on 

 moist slopes facing sea. In north coast region it thrives on very thin, light moist soils; 

 also follows moist soils eastward and on mountain slopes. Best growth in constantly 

 moist, deep rich soils, and in humid atmosphere. Deficient moisture occasions stunted 

 growth. Quantity and quality of soil more important as soil moisture and the humidity 

 decrease, and vice versa. Endures considerable inundation in coast flood plain, but 

 usually grows a short distance from water's edge. 



Forms pure forests, especially at north, and occurs in mixed stands, most commonly 

 with western hemlock; associated also with redwood, western red cedar, lowland Or, 

 yellow cedar. Pacific yew, black hemlock ; occasionally with Douglas fir, broadleaf and 

 vine maples, Sitka alder, black Cottonwood, willows, etc. Sitka spruce and western hem- 

 lock are the chief components of Alaskan coast forests, where one or the other becomes 

 dominant : the spruce is usually dominant on the coast, while hemlock holds higher ele- 

 vations and areas away from coast. 



Climatic CONDITIONS. — Climatic conditions of range very favorable to forest growth. 

 Climate generally mild and uniform, especially through influence of sea and warm sea 

 current from Japan. Precipitation heavy ; humidity high, and dense fogs abundant ; 



