282 TREES IN" WINTER 



YELLOW BIRCH 

 Silver or Gray Birch. 



Betula lutea Michx. f. 



HABIT — A large tree 60-90 ft. in height, with trunk diameter of 

 2-4 ft., reaching its largest size in northern New England; in the open 

 branching low down with long slender wide spreading somewhat 

 pendulous branches forming a broadly ovate to hemispherical head. 

 Older tree^ than the one photographed generally show a broader outline 

 twith the trunk less conspicuously continuous into the head. 



BARK — On young trunks and branches close, bright, silvery-yellow- 

 ish gray, generally at length peeling into thin ribbon-like layers which 

 roll back and extend up the trunk in long lines of ragged fringe. There 

 is considerable variation in the amount of peeling of the outer bark. A 

 well marked condition of peeling is shown in the bark photographed; 

 the bark of the tree used for the habit showed scarcely any peeling. On 

 older trunks especially toward the base the silvery bark is entirely 

 shed and the bark below shows reddish-brown and becomes rough and 

 fissured into irregular plate-like scales. 



TWIGS — Slender, light yellowish-brown, becoming darker, smooth or 

 somewhat hairy; with only slight wintergreen flavor when chewed; 

 short spur-like lateral branches abundant, similar to those of Black 

 Birch. LENTICELS — pale, raised dots, inconspicuous, becoming horizon- 

 tally elongated with age. 



L.EAF-SCARS — Alternate, 2-ranked, similar to those of Black Birch, 



BUDS — Similar to those of Black Birch, more or less appressed. 

 BUD-SCALES — more or less downy. 



FRUIT — An erect, stalkless or short-stalked downy catkin, ovate to 

 oblong, 2-4 cm. long and about 2 mm. wide and relatively wider than 

 fruit of Black Birch; scales downy on the back and edges, 8-10 mm. 

 long, longer than broad, nearly equally 3-lobed to the middle; with 

 seed-like winged nutlets about as broad as their wings. 



COMPARISONS — The Yellow Birch differs from the Black Birch as 

 indicated in Comparisons under the latter species. In the peeling of the 

 outer bark it resembles the Paper and the Red Birch. Its outer bark, 

 however, is a dingy yellow and not a chalky white as is that of the 

 exposed layers of the Paper Birch; moreover, in peeling, the thin layers 

 tend to curl back to form longitudinal lines of ragged fringe. The 

 fringes of bark are larger and more ragged than in the Red Birch 

 but the color alone is sufficient to distinguish the two forms. 



DISTRIBUTION — Low, rich woodlands, mountain slopes. Newfound- 

 land and Nova Scotia to Rainy river; south to the middle states, and 

 along the mountains to Tennessee and North Carolina; west to Minne- 

 sota. 



IN NEW ENGLAND — Abundant northward; common throughout, from 

 borders of lowland swamps to 1,000 feet above the sea level; more 

 common at considerable altitudes, where it often occurs in extensive 

 patches or belts. 



W^OOD — Heavy, very strong, hard, close-grained, light brown tinged 

 with red, with thin nearly white sapwood; largely used in the manufac- 

 ture of furniture, button and tassel moulds, boxes, the hubs of wheels 

 and for fuel. 



