258 FOREST TREES OF THE PACIFIC SLOPE. 



somewhat upright, from seven-eighths inch to about 1 inch long and approxi- 

 mately three-eighths inch thick. Cone-scales, minutely hairy on their margins 

 (fig. 112, c), and the very small seeds (nuts) with thin wings on two sides (fig. 

 112, b). Wood : Nothing is now known of the characteristics of the wood, 

 which, however, on account of the tree's rarity, can be of little commercial use. 

 Longevity. — No records are available of the age of the tree or of its silvical 

 requirements, concerning which observations are needed. 



RANGE. 



Only on sea side of coast mountains of Alaska from head of Lynn Canal westward to 

 Kenai Peninsula and north end of Kodiak Island. Here, associated with Picca sitchrn- 

 sis and Betula alaskana, and reaching the same elevations as spruce ; on Lynn Canal, 

 growing to about 2.600 feet elevation; on Prince William Sound, to about 1,600 feet; 

 while on Kenai Peninsula it is abundant on top of plateau, extending up slopes to about 

 2,000 feet. At Sunrise, on shore of Turnagain Arm, and southward on west shore of 

 Cook Inlet to Halibut Cove, Kachemak Bay ; possibly extending inland, around head of 

 Alaskan Peninsula, into the interior and up Sushitna and Copper rivers, as well as over 

 passes at head of Lynn Canal. Reported on Koyukuk River above the Arctic Circle. 

 A few trees occur back of Kodiak village on Kodiak Island, while the species grows 

 abundantly in valley at head of English or Womens Bay, 8 miles south of Kadiak 

 village. 



White Birch. 



Betula old skan a Sargent. 



DISTINGUISHING CHARACTERISTICS. 



White birch is a little-known Alaskan species. Its possible relationship to 

 some of the imperfectly known Asiatic white-barked birches has not been deter- 

 mined. The earliest record of it is from specimens collected on the Saskatchewan 

 River in 1S5S, after which date its identity was in doubt until 1901. There is 

 still much to be learned of its forest habits. 



Ordinarily from 25 to 35 feet high — sometimes 50 or 60 feet, and about one- 

 half foot to 1 foot through. The hard, firm bark of large trees is thin, occasion- 

 ally almost white, but usually light reddish-brown, and is separable into thin 

 scales. The slender twigs, reddish-brown and smooth, are conspicuously covered 

 with minute, resinous, gland-like specks, as are also the young leaves. Mature 

 leaves (fig. 113). thin, smooth, deep green on their top sides, lighter green be- 

 neath, and smooth or minutely hairy on the small veins, as are often the deli- 

 cate, reddish leaf stems. Mature cones (fig. 113) more or less drooping, from 

 1| to about li inches long and approximately one-third inch through. Cone 

 scales (fig. 113, c) minutely hairy on the margins: the very small seeds (nuts) 

 have broad delicate wings on two sides (fig. 113, &). Wood: Nothing is now 

 known of its quality and other characteristics. The fairly abundant occurrence 

 of the tree may render the wood, which is probably similar to that of the east- 

 ern paper birch, of commercial importance for some of the same purposes (small 

 turnery, etc.) for which that timber is extensively used. 



Longevity. — No records are available of age. 



RANGE. 



Western British America and Alaska from Saskatchewan River ftnd northern Rockies 

 northward to mouth of Mackenzie River : on south side of Endicott Range, in Alaska, 

 and westward to the Arctic Ocean and Bering Sea ; and south to sea side of Alaskan 

 Pacific coast ranges. Distribution imperfectly known. 



Wbsteen Canada. — Saskatchewan River and westward from Prince Albert (about 

 lat. 5S°, long. 106°) ; northward (probably only near eastern base of Rockies), to 



