Heart-Leaved Paper Birch 



251 



red-brown, and, after several years' growth, bright white like the trunk. The 

 buds are ovoid, pointed, about 7 mm. long, some- 

 what hairy and resinous. The leaves are ovate, 

 3 to II cm. long, sharply irregularly toothed, 

 rather firm in texture, hairy when young, and 

 hairy in the axils of the veins beneath even when 

 old, the upper surface dark green and dull, the 

 under side light green; they are either rounded 

 or narrowed at the base; the leaf-stalks are 1.5 

 to 3 cm. long, the stipules ovate, pointed, and 

 hairy-fringed. The flowers open with or before 

 the leaves in April or May. The staminate cat- 

 kins are borne 2 or 3 together and vary from 5 , ^x \ \ Vk I 

 to 10 cm. long, their scales triangular-ovate and . v ^^^"^i^Vlxv ^ 

 finely hairy. The ripe pistillate catkins are 



cylindric, 2 to 5 cm. long, with stalks i to 2 



, .7.1 i /: 1 Fig. 206. — Paper Birch, 



cm. long; their scales are 4 to 6 mm. long, 



smooth or finely hairy, their lateral lobes shorter than or as long as the middle one; 



the oblong or oval nut is somewhat narrower than its wings. 



The wood is light brown, strong and tough, with a specific gravity of about 



0.60; it is largely used for spools, and also for shoe-pegs and paper-pulp; it was 



utihzed for a variety of purposes by the northern Indians, who also employed the 



bark extensively for canoes, baskets, and cups, and for sheathing wigwams. The 



tree is of rapid growth but does not yield readily to cultivation much to the south 



of its area of natural distribution. 



Fig. 207. — Heart-leaved Paper Birch. 



5. HEART-LEAVED PAPER 

 BIRCH — Betula cordifoHa Kegel 



This tree closely resembles the widely 

 distributed Paper birch, except in the 

 form of its leaves. It is smaller than that 

 species, perhaps reaching a maximum 

 height of not more than 14 meters, with a 

 trunk 2 dm. thick. It occurs in the north- 

 em and mountainous parts of North 

 America, extending from Newfoundland 

 to British Columbia, Maine, northern New 

 York, Iowa, Idaho, and Washington. 



The outer bark is bright white, the in- 

 ner orange-yellow; it peels readily. The 

 young twigs are green and sometimes 

 glandular, becoming brown. The leaves 



