202 



TREES OF NORTH AMERICA 



scales; pistillate aments slender, about J' long, with acuminate pale green much re- 

 flexed scales. Fruit: strobiles cylindrical, pubescent, slightly narrowed at the obtuse 

 apex, about 1' long and ^' thick, pendant on slender peduncles \'-^' in length; nut 

 oval, much narrower than its broad wing. 



A tree, rarely more than 30 high, with a trunk 8'-10' in diameter, small ascend- 

 ing finally spreading branches, and slender branchlets marked by numerous small 

 raised pale lenticels, purplish and sparingly villous when they first appear, soon 

 glabrous, becoming bright red-brown; often forming clumps of several stems. Bark 

 thin, white tinged with rose, lustrous, not readily separable into layers, the inner 

 bark light orange color. 



Distribution. Moist slopes, Stratton and Windham, Vermont, at elevations of 

 about 1800 (W. H. Blanchard), Haystack Mountain, Aroostook County, Maine 

 (M. S. Fernald) ; the American representative of the European Betula pendula, 

 Roth., and probably widely distributed over the hills of northern New England and 

 eastern Canada. 



Apparently passing into a form with larger leaves often rounded and truncate at 

 the broad base and 3'-3^' long and 2' wide, stouter staminate aments, and strobiles 

 frequently 1^' long and \' thick (var. Blanchardi, Sarg. nov. nom. fig. 168 A). This 

 under favorable conditions is a tree 60-70 high, with a trunk 18' in diameter, and 

 possibly when better known may be considered a distinct species; common with 

 Betula ccerulea at Windham and Stratton, Vermont (H. W. Blanchard), and on a 

 hill near the coast in Washington County, Maine (M L. Fernald'). 



-I t- Scales of the strobiles unth ascending or spreading lateral lobes, the middle 

 lobe longer than broad ; leaves acute or acuminate. 

 ++Bark creamy white to reddish broum, separating freely into thin layers. 



6. Betula papyrifera. Marsh. Canoe Birch. Paper Birch. 



Leaves ovate, acute or acuminate, with short broad points, coarsely usually 

 doubly and often very irregularly serrate except at the rounded abruptly wedge- 

 shaped, gradually narrowed, or deeply cordate (var. cordifolia, Fern.) base, bright 



green, glandular-resinous, pubescent and clothed below on the midribs and primary 

 veins and on the petioles with long white hairs when they unfold, at maturity thick 



