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RED OAK. 



Quercus rubra, Linnaeus. 



FORM One of the largest forest trees of the Northern States, usually attaining a height 

 of 70-90 ft. with a diameter of 2-4 ft. but occasionally reaching a height of 150 ft. with a 

 diameter of 5 feet. When grown in the open has a short trunk and a broad symmetrical crown; in 

 dense forest stands the trunk is straight, clean and continuous bearing a small, narrow crown. 

 The straight ascending and clean branches of the crown are characteristic. 



BARK On young stems and branches smooth, gray to brown; on older trunks it is thick, 

 slowly broken up by shallow fissures into regular, continuous, dark-brown and distinctly flat- 

 topped ridges. Trunks above 8 ft. in diameter are often very rough near the base, having 

 lost the characteristic flat-topped ridges which are, however, retained higher up on the 

 stem. See Fig. 72. 



TWIGS Rather slender, smooth, greenish-brown to dark brown, covered with pale indistinct 

 lenticels; pith star-shaped. 



BUDS Alternate, ovoid, 1/6-1/3 of an inch long, widest part near middle, narrowed up- 

 ward to a sharp point, light brown, and free from woolly covering. Bud-scales numerous, 

 overlapping, light brown, slightly longitudinally-striate, with slightly pubescent margins. 



LEAVES Alternate, simple oval to obovate in outline, 5-9 inches long, 4-6 inches wide, 

 7-9-lobed, with sinuses extending half-way to the midrib and separating ascending lobes with 

 entire margin or few bristle-pointed teeth. Mature leaves firm, dull green, with yellowish to 

 reddish midrib above and pale with a yellowish midrib below. 



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



FLOWERS Appear about May when leaves are about I developed. Staminate borne in 

 slender, hairy aments 4-5 inches long, with greenish 4-5-lobed calyx and 4-5 stamens terminated 

 by yellow anthers. Pistillate borne on short stalks; involucral scales broadly ovate, blunt, 

 pubescent; calyx lobes sharp-pointed; style spreading recurved, light green. 



FRUIT An acorn, maturing at the end of second season, solitary or paired, short-stalked. 

 Nut ovoid, -lJ inches long, flat at base, narrowed at apex. Cup velvety inside, broad, 

 shallow, covering only base of nut, with closely imbricated, sometimes hairy, reddish-brown 

 scales. Immature acorns usually divergent from twig, with basal scales reaching about 

 I of the way up, and appearing as if arranged in 3 rows. 



WOOD Ring-porous; with conspicuous medullary rays; heavy, strong, hard, close-grained, 

 light reddish-brown, with thin lighter colored sapwood. Used for furniture, cooperage, con- 

 struction, interior finish of houses, and railroad ties. Weighs 41.25 Ibs. per cubic foot. 

 The wood of this species as well as that of the Black Oak and Scarlet Oak. is relatively poor 

 but is coming more into use daily. The despised species of to-day may be prized to-morrow. 



DISTINGUISHING CHARACTERISTICS The Red Oak may be recognized by its flat-topped 

 ridges of the bark, its straight clean branches, its large dull green leaves with red midribs 

 and ascending lobes with entire or few bristle-teeth, its light reddish inner bark, its glabrous, 

 sharp-pointed, light brown buds which are often constricted at the base, and its large acorns 

 with broad and shallow cups. 



RANGE Nova Scotia to Minnesota and Kansas, south to Florida and Texas. Planted 

 extensively in Europe for ornamental and forestry purposes. 



DISTRIBUTION IN PENNSYLVANIA Found throughout the State. At its optimum in the 

 Cumberland Valley and adjoining lower slopes. Rarer in the northern than in other parts. 



HABITAT Prefers porous sandy or gravelly clay soil. It will not grow in wet soils and 

 is also intolerant of shade, except when young. 



IMPORTANCE OF THE SPECIES The Red Oak is the most rapid growing species of all 

 the Oaks. In one year it has grown to the height of 19 inches, in 10 years 18 feet, 20 years 

 33-39 feet, 50 years 50-57 feet. It deserves to be planted and regenerated naturally on an 

 extensive scale. In a single small nursery the Pennsylvania Department of Forestry in 1911 

 raised over 200,000 seedlings of this species. In Germany it has at present a wider distri- 

 bution than any other American hardwood species. It is very attractive ornamentally on 

 account of its smooth bark, straight branches, and the form and autumnal coloration of its 

 leaves. 



