116 



YELLOW BIRCH. 

 Betula lutea, Michaux. 



FORM — A large tree usually attainins a height of GO-SO ft. with a diameter of 2-3 ft.. 

 hut may reach a maximum height of 100 ft. with a diameter of 3-4i feet. Trunk in the 

 open usually short, branching near the base; its long slender branches forming a wide open 

 rather hemispherical crown, in close stands often rather free from lateral branches. 



BARK — Close aod furrowed or peeling off In thin yellow film -like papery scales. Varies 

 with the age and location of the tree. On young truulis and branches rather close, shining, 

 yellow but soon forming a ragged fringe, later peeling off into thin, yellow, film-like, papery 

 layers. On old trunks it finally becomes rcddi»b-brown and roughened with fissures. The ragged 

 bark is fften pulled off and used by campers to start fires in wet weather. See Fig. 68. 



TWIGS — At first green and hairy, later biown and smooth, finally dull silvery-gray. Terminal 

 twigs loug and slender; lateral short .^nd stout; usually covered with elongated horizontal 

 lenticels which in time unite to form a long horizontal line. 



BUSS — Similar to those of the Black Birch, but sometimes slightly more downy. See 

 page lis. 



LEAVES — Alternate, simple, occur singly or in pairs but never opposite. 3 4 inches long. 

 ovate, wedge-shaped or heart-shaped at base, doubly serrate on margin, acute at apex, dull 

 green above, yellowish -green below. 



LEAF-SCABS — Similar to those of the Black Birch in particular, and all of the other 



Birches in gene.-al. 



FLOWEHS — Appear about April before tlie leaves. Staminate and pistillate separate, but 

 usually on the same branch. Staminate are formed in the fall, remaining over winter as 

 amenta about 3 of an Inch long which elongate to about 3 inches in spring. PistiUate about 

 8 of an inch long, with acute scales which are light red and hairy above, and green below. 



FRUIT — An erect, usually very short-stalke-l strobile, about 1-li inches long, ovate in out- 

 line, consisting of numerous 3-lobed scales fastened to a central axis and bearing small 

 winged nuts with rather narrow wings. 



"WOOD — Diffuse-porous; rays indistinct; heavy, hard, strong, compact, not durable when 



in coutact with the' soil. Heart-wood light brown, tinged with red; sap-wood pale in color. 



Weighs 40.84 pounds per cubic foot. Used fo* furnitare, flooring, interior finish, boxes, certain 

 veneeis and fuel. 



DISTnTGUISHTNG CHAR ACTEEISTICS— The YeUow Birch, also known as Silver and Gray 

 Birch, can readily bu dittiu^uished from the other Birches of Pcunsylvania by its yellow bark 

 which peels off into thin, film-like, papery scales. Its method of peeling the bark resembles 

 that of the Paper Birch and the Bed Birch, but it does not have the white color of the 

 former nor the reddish to greenish-lirown color of the latter. The loose, fillti-Uke. papery scales 

 of the Red Birch are smaller than those of the Yellow Birch and the strobiles of the former 

 are slender-stalked while those of the latter are usually sessile or very short-stalked. 



RANGE — Newfoundland, south to Pennsylvania, and along the mountains to North Carolina 

 and Tennessee, west to Minnesota. 



DISTRIBUTION IN PENNSYLVANIA— Found locally throughout the State but most common 

 in the Alle2;henies. 



HABITAT — Common on moist rich uplands, borders of streams, and in swamps. 



IMPORTANCE OF TEE SPECIES — The Yellow Birch is one of the largest deciduous trees 

 of northeastern America. Until recently the value of its wood was not fully appreciated, 

 but today it holds a fair position on the lumber market and in the future it will no doubt 

 attain a still better position. It has been classed as one of the most artistic, reliable, and 

 versatile of tJie hardwoods of this country. With all its good qualities, it has superior 

 associates and consequently cannot be recommended for forestry purposes except on the 

 farmer's woodlot whe.v fuel is especially desired and in such other places where it comes 

 up naturally and ofier more desired species will not grow to advantage. 



