142 



BLACK OAK. 



Quercus velutina, Lambert. 



FORM — One of the largest Oaks of Pennsylvauia usually 60-SO ft. high, but may attain a 

 maximum height of 150 ft. with a diameter of 4i feet. Trunk usually clean and continuoas 

 giving off ascending branches above and horizontal ones below. Branches rather stout and 

 zigzag. Crown deep, irregular, narrow to wide-spreading, oblong in outline. 



BARK — On young stems smooth and dark brown, but soon becoming rough and black. 

 On old trunks very rough, thick, broken into deep fissures separating thick ridges which are 

 cross-fissured. Young trees 2-4 inches in diameter often start to develop rough bark. Inner 

 bark is yellow and bitter, a good distinguishing characteristic. See Fig. 74. 



TWIGS — Stout, rusty -pubescent, reddish-brown, angular, longitudinally ridged from leaf- 

 scars; taste bitter; covered by rather conspicuous pale lenticels. 



EITDS — Alternate, ovate, large, i-J of an inch long, strongly angled, tapering to obtuse apex, 

 covered with numerous overlapping bud-scales with a coating of yellowish to dirty-white 



jFUbescence. 



LEAVES — Alternate, simple, obovate to oblong. 4-6 inches long, 3-4 inches wide, usually 7- 

 lobed terminated by bristle points. Mature leaves are dark green and smooth above and pale 

 to yellowish-green below with tufts of rusty hairs in axil of veins at midrib. The leaves 

 vary from those of the Red Oak. No other Oak produces so many differently shaped leaves 

 on the same tree. 



LEAF-SCARS — See "Leaf -Scars" under White Oak, page 132. 



FLOWERS — Appear about May when leaves are i developed. Stamlnate flowers occur 

 in hairy aments 4-G inches long. Pistillate are borne on short hairy stalks. 



FRUIT — An acorn, maturing during two seasons, sessile or stalked, solitary or clustered. 

 Nut orate to oval, i-1 inch long, light reddish-brown, often coated with pubescence and 

 longitudinally striate. Cup thin, tapering at base, dark reddish-brown, embracing i nut, covered 

 with thin, light brown, sharp-pointed, hairy scales tightly overlapping at base and loosely 

 overlapping at margin so as to form a fringe-like margin to the cup. 



WOOD — Ring-porous; with conspicuous medullary rays; hard, . heavy, strong, not tough, 

 durable, checks readily. Heart wood is light brown, with lighter-colored sapwood. Weighs 

 43.90 lbs. per cubic foot. TJsed for furniture, interior finish, cheap cooperage, and ordinary 

 construction. In general it finds the same uses as Red Oak. 



DISTINGUISHING CHARACTERISTICS— The Black Oak is also known as Yellow Oak 

 and Quercitron on account of its yellow inner bark. The dark colored and rough outer bark, 

 even on young stems, and the yeUow inner bark are at all seasons of the year definite 

 marks of identification. The leaves, which vary from the shallow lobed ones similar to 

 those of the Red Oak to the deep lobed ones similar to those of the Scarlet Oak, may also 

 help to identify the species. No other species of Oak has so many varieties of leaves 

 on the same tree as the Black Oak. In autumn the small acorns with the cup embracing 

 one-half of the nut may also help to distinguish it from some species like the Red Oak 

 and the Pin Oak. The large, angular buds covered over the whole surface with a pale 

 wool ar<} sure characteristics. 



RANGE — Maine to Western Ontario, south to Florida and Texas. 



DISTRIBUTION IN PENNSYLVANIA — Common In the eastern, central, and southern parts. 

 Sparse in western part. Rare in the northern part. 



HABITAT — TTsually found on dry uplands, gravelly plains and ridges, especially In the 

 Appalachian foothills. Seldom found In rich bottomlands. In the west usually found on 

 sterile, sandy, or glaciated hiUs. 



IMPORTANCE OF THE SPECIES — The Black Oak should be propagated only where no 

 bettor trees can be grown. If its reproduction is thought desirable It should be attempted 

 by natural seed regeneration or planting of seeds since planting of young seedlings from the 

 nursery is expensive and success doubtful. Formerly the yellow inner bark was In demand 

 because an extract in the form of a yellow dye. known as "Quercitron." was obtained 

 from it. The introduction of aniline dyes has decreased the demand. The Black Oak is not 

 attractive as an ornamental tree. 



