BETULACE^E 



205 



A tree, 100-120 high, with a trunk 3-4 in diameter, comparatively small 

 branches often pendulous on old trees, and pale orange-brown brauchlets more or less 

 glandular and coated with long pale hairs when they first appear, becoming bright 

 orange-brown and marked by numerous minute pale lenticels and pubescent or 

 puberulous during their first winter and nearly destitute of glands, and in their 

 second year orange-brown, glabrous, and very lustrous. Winter-buds acute, bright 

 orange-brown, ^'-^' long, their light brown inner scales sometimes becoming ' long. 

 Bark thin, marked by large oblong horizontal raised lenticels, dark orange-brown, 

 very lustrous, separating freely into thin papery layers displaying in falling the 

 bright orange-yellow inner bark. 



Distribution. Banks of streams and lakes ; southwestern British Columbia and 

 northwestern Washington ; nowhere common and probably of its largest size on the 

 alluvial banks of the lower Fraser River, and on the islands of Puget Sound. 



8. Betula Kenaica, Evans. Red Birch. Black Birch. 



Leaves ovate, acute or acuminate, broadly cuneate or somewhat rounded at the 

 entire base, irregularly coarsely often doubly serrate above, puberulous on the upper 



surface and ciliate on the margins when they unfold, at maturity glabrous, dark 

 dull green above, pale yellow-green below, l^'-2' long, I'-lf ' wide, with slender yel- 

 low midribs and 5 pairs of thin primary veins ; their petioles slender, J'-l' long. 

 Flowers : staminate aments clustered, 1' long, with ovate acute scales apiculate at 

 the apex, puberulous on the outer surface ; pistillate aments ^' ^' long, about ^' 

 wide, on slender glandular pubescent peduncles -J' |' long, with acuminate light 

 green strongly reflexed scales; styles bright red. Fruit : strobiles cylindrical, gla- 

 brous, V long, their scales ciliate on the margins; nut oval, somewhat narrower than 

 its thin wing. 



A tree, 30 -40 high, with a trunk 12'-2(X in diameter, wide-spreading branches, 

 stout branchlets marked by numerous small pale lenticels, bright red-brown during 

 2 or 3 years, gradually becoming darker. Bark thin, more or less furrowed, very 

 dark brown or nearly black near the base of the trunk, grayish white or light red- 

 dish brown and separating into thin layers higher on the stem and on the branches. 



