PAPER BIRCH 



(Betula Papyri/era) 



THIS tree is called paper birch because the bark parts in thin sheets 

 like paper. It is known as canoe birch from the fact that Indians 

 and early white explorers and travelers constructed canoes of the bark. 

 The name silver birch is an allusion to the color of the bark; and big 

 white birch is the name used when the purpose is to distinguish it from 

 the white birch with which it is associated hi the northeastern part of 

 its range. It grows as far north as Arctic British America, east to 

 Labrador, south to Michigan and Pennsylvania, and west nearly or 

 quite to the base of the Rocky Mountains. This indicated area exceeds 

 1,000,000 square miles. The quantity of birch of this species in the 

 forests is unknown, but it runs into billions of feet, probably exceeding 

 any other single species of birch. The tree sometimes grows dispersed 

 through forests of other woods, sometimes in nearly pure stands. Persons 

 well acquainted with the species have expressed the opinion that paper 

 birch exists hi larger quantities now than at the time when the country 

 was first explored by white men. That can be said of few other species; 

 but probably holds true of lodgepole pine hi the West, loblolly pine in 

 the Southeast, and mesquite hi the Southwest. Each of these species 

 took advantage of man's presence and influence to extend its range. 

 Cattle spread the mesquite; the lodgepole pine came up hi fire-burned 

 tracts; loblolly pine spread into abandoned fields; and paper birch profit- 

 ed by fires which destroyed large tracts of timber. 



The seeds are light, are furnished with wings which sail them long 

 distances through the air, and they are quickly scattered over the 

 burned areas where they spring up. In the contest, they are com- 

 petitors of aspen. Birch often captures the ground, but does not 

 always do it. Some of the largest stands in the Northeast occupy tracts 

 bared by fire half a century or more ago. When paper birch does not 

 find open tracts, it contents itself with sharing ground with other 

 species. That was the usual manner of its growth hi the original forests ; 

 but it has been quick to seize opportunities to take full possession. 



It does not like shade and, if crowded, one of the first things it does 

 is to rid its lower trunk of all branches. Only limbs remain which 

 are at the top where they receive plenty of light. Therefore, forest- 

 grown paper birches have long, dean trunks, though they are not always 

 straight. The largest trees are seventy feet high and three in diameter, 

 but those fifty feet in height and eighteen inches in diameter are above 

 rather than under the average. 



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