196 



AMERICAN FORESTRY 



field or poverty birch 

 because it so quickly 

 takes possession of aban- 

 doned fields in New 

 England. Gray birch is 

 also a common name, de- 

 rived from the color of 

 the outer bark, which has 

 a grayish cast a much 

 duller white than that 

 of paper birch. It can- 

 not be peeled off in 

 papery layers. Beneath 

 each side branch is a 

 V-shaped black blotch. 

 The twigs are more slen- 

 der and droop even more 

 gracefully than those of 

 paper birch; they are 

 also much more notice- 

 ably roughened by 

 resinous dots on the sur- 

 face of the bark. 



White birch is always 

 a small tree, seldom 

 reaching a greater size 

 than 25 to 40 feet in 

 height, and a foot in 

 diameter. It grows from 

 Nova Scotia to the 

 southern shores of Lake 

 Ontario, and south to 

 Delaware, principally 

 along the coast. It is 

 found most frequently 

 on dry, gravelly soils, 

 but occasionally in moist 

 ground. It is a sun-lov- 

 ing, vagabond tree, 

 quickly taking posses- 

 sion of burned forest 

 areas or abandoned 

 fields, but is short-lived 

 and unable to compete 

 with other trees that spring up in its grateful shade. 



The European white birch (Betula alba) is often 

 planted for ornament and is the only other tree that is 

 liable to be mistaken for either white or paper birch. It 

 is so closely related to paper birch that the latter is 

 generally considered a botanical variety of the European 

 species. A very common form has "weeping branches," 

 another has finely divided "cut" leaves. The bark at 

 the base of large trunks has deep, dark-colored furrows. 

 The outer bark has the chalky whiteness of paper birch, 

 but does not so readily separate into thin layers. 



Sweet birch (Betula lenta) is also known as black or 



r<d birch, cherry birch and mahogany birch. It ranges 



from Newfoundland to northwestern Ontario, southward 



to southern Illinois and along the Allegheny Mountains 



) western Florida. Its average size is 50 to 60 feet 



(p) pistillate 



WHITE OR PAPER BIRCH 



1. Flowering branch with immature leaves, (s) staminate flowers 

 flowers; one-half size. 



2. Branch with mature leaves, fruiting strobiles and partly developed staminate 

 aments; one-half size. 



8. A winged seed. 



4. A stroble scale, enlarged. 



5. A winter branch. 



6. Section of lateral winter spur-branch, enlarged. 



7. Section of a terminal winter branch, enlarged. 



high and 1 to 3 feet in 

 diameter, but it occa- 

 sionally grows 80 feet 

 high and 5 feet through. 

 Old trees with plenty of 

 space for growth de- 

 velop handsome, spread- 

 ing tops, with heavy, 

 twisted branches and an 

 abundance of slender, 

 pliable twigs. In the for- 

 est, mature trees have 

 clear and fairly straight 

 trunks and rounded, 

 rather broad and heavy- 

 branched tops. Young 

 trunks and branches have 

 smooth, shining bark of 

 a dark reddish-brown 

 color, looking much like 

 the bark of the common 

 sweet cherry. Old trunks 

 are covered with large, 

 thick, irregular plates of 

 bark, the edges of which 

 curl stiffly back. The bark 

 does not peel in papery 

 layers, but is smooth on 

 the surface between the 

 furrows and is dark 

 brown, almost black, in 

 color. The inner bark 

 gives the best clue by 

 which to identify sweet 

 birch. It has a fragrant 

 odor and a strong flavor 

 of wintergreen. Indeed, 

 sweet birch bark for- 

 merly produced most of 

 the commercial oil of 

 wintergreen. The pleas- 

 ant-tasting bark is not 

 the only delightful tid- 

 bit this tree supplies to the woodsman. The sap is sweet 

 and inviting, either in its natural state or when brewed. 

 Strips of inner bark, dried in the spring when it is rich 

 in starch and sugar, have been used for food. 



Yellow birch (Betula lutea) is an important timber 

 tree of the northern forests. It grows on rich, moist, 

 well-drained soil from Newfoundland to southwestern 

 Ontario and northern Minnesota south to Delaware, and 

 in the Appalachian Mountains to North Carolina and east- 

 ern Tennessee. Its ordinary size is 60 to 80 feet in 

 height, and 2 to 3 feet in diameter. In form it closely 

 resembles the sweet birch, but tends to have a more 

 spreading habit. Its bark has a distinct dingy yellow 

 color and the outer portion can be pulled away in thin, 

 filmy ribbons. Young trees have smooth, glistening, sil- 

 very bark, and for this reason the tree is called by some 



