BETULACEAE 

 Paper Birch. Canoe Birch. White Birch 



Betula alba papyrifcra (Marsh.) Spach. [Betula papyrifera 

 Marsh.] 



HABIT. A tree 50-75 feet high, with a trunk diameter of 

 1-3 feet, forming in youth a compact, pyramidal crown of many 

 slender branches, becoming in old age a long, branchless trunk 

 with a broad, open crown, composed of a few large limbs ascend- 

 ing at an acute angle, with almost horizontal branches and a 

 slender, flexible spray. 



LEAVES. Alternate, simple, 2-3 inches long, iJ^-2 inches 

 broad; ovate; coarsely, more or less doubly, serrate; thick and 

 firm; glabrous, dark green above, lighter beneath, covered with 

 minute black glands ; petioles stout, yellow, glandular, glabrous or 

 pubescent. 



FLOWERS. April, before the leaves ; monoecious ; the stam- 

 inate catkins clustered or in pairs, 3-4 inches long, slender, pend- 

 ent, brownish; the pistillate catkins about i^j inches long, slender, 

 erect or spreading, greenish; styles bright red. 



FRUIT. Ripens in autumn; long-stalked, cylindrical, glab- 

 rous, drooping strobiles, about l l /z inches long; scales hairy 

 on the margin ; nut narrower than its wing. 



WINTER-BUDS. Terminal bud absent; lateral buds > 

 inch long, narrow-ovoid, acute, flattish, slightly resinous, usually 

 divergent. 



BARK. Twigs dull red, becoming lustrous, orange-brown ; 

 bark of trunk and large limbs cream-white and lustrous on the 

 outer surface, bright orange on the inner, separating freely into 

 thin, papery layers, becoming furrowed and almost black near the 

 ground. 



WOOD. Light, hard, strong, tough, very close-grained, 

 light brown tinged with red, with thick, whitish sapwood. 



DISTRIBUTION. Lansing and northward. Common in 

 central Michigan as a small tree. Of larger size in the Upper 

 Peninsula. 



HABITAT. Prefers rich, moist hillsides; borders of, 

 streams, lakes and swamps ; but is also found in drier situations. 



NOTES. A rapid grower in youth. The bark is used by the 

 Indians and woodsmen for canoes, wigwams, baskets, torches, etc. 

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