The Birches 69 



soils and is often one of the first trees to spring up after a forest fire. Occasionally 

 it is found in wet ground along the margin of streams and swamps. 



It is a small tree, rarely over 30 or 35 ft. in height. The trunk usually extends 

 undivided to the top of the tree. The branches are slender and divide into many 

 long, fine, flexible branchlets that have a tendency to droop. The ends of the twigs 

 are rough to the touch. 



The bark on the trunk and larger branches is thin and white, but it does not 

 split readily into papery layers as does that of the canoe birch. On the trunk be- 

 neath each limb is a triangular black spot that is characteristic of this tree. The 

 bark at the base of the trunk on the larger trees is frequently broken by irregular 

 fissures. 



The winter buds are slender, brown, about ^4: in- long, pointed, and waxy. 

 Those of the canoe birch, for which this tree might be mistaken, are larger and some- 

 what sticky. 



The leaves are 2}/^ to 3 in. long, triangular in outline, with a long, tapering 

 point. The margin is double- toothed and the upper surface is bright green and 

 shiny. The stems are smooth and long, longer than those of the paper or canoe 

 birch, and the leaves are therefore agitated by the slightest breeze and flutter as 

 freely as those of the aspen. 



As this tree rarely reaches commercial size in Canada its wood is seldom used. 

 It is the toughest of all the birches and the most perishable. It is used occasionally 

 for barrel hoops and hockey sticks. 



BETULA ALBA, L., var. PAPYRIFERA (Marsh.) Spach. PAPER BIRCH 

 Common names: Paper birch, canoe birch, silver birch, white 



birch*. 

 French names: Bouleau blanc*, bouleau a papier, bouleau a canot. 



The paper, or canoe, birch has an extremely wide range in Canada, being found 

 from Labrador and the Maritime Provinces westward to Yukon territory and to 

 the north Pacific coast. Along with tamarack, white spruce and black spruce, 

 balsam poplar and aspen, it reaches its northern limit near the mouth of the Mac- 

 kenzie river. 



It is a tree rarely over 70 ft. in height or with a diameter over 18 in. Ordin- 

 arily it is about 50 ft. high and 8 to 10 in. in diameter. In the forest the trunk is 

 long and clear but in the open it is short, and the crown is large, irregular, and 

 composed of many upright branches. 



The white, tough, easily split, thin, papery bark of the trunk and larger limbs 

 is too well known to need further description. The white birch is the only other 

 tree the bark of which is likely to be mistaken for that of this tree ; and the white 

 birch can be distinguished from it by the fact that the bark of the latter is usually 

 of a dirty white colour, with a chalky surface, and will not separate into thin sheets 

 as readily as that of the paper birch. 



The branches are stouter than those of other birches, and they do not tend 

 to droop as do those of the white birch. The twigs are also smoother and coarser 



