340 



The Oaks 



winter buds are brown, their scales thin and hairy. The leaves are broadly ob- 

 ovate in outline, 6 to lo cm. long, the 7 to 9 lobes oblong to obovate, seldom 

 lobed at the rounded apex, the sinuses deep and broad or narrow, slightly rounded 

 at the bottom, the leaf base rather broad and rounded; they are thick and firm, 

 dark green, shining and slightly hair\^ above, paler, brownish, softly downy, with 

 prominent venation beneath; the petiole is about i cm. long and slightly hairy. 

 The nearly sessile fruit ripens the first season; nut ovoid-oblong, 1.5 to 2 cm. 

 long, blunt-pointed, light brown; cup hemispheric, 12 to 15 mm. across, embrac- 

 ing about one half the nut, covered with ovate, corky-thickened, hairy scales. 



60. COLORADO WHITE OAK Quercus leptophylla Rydberg 



This tree, known only from Colorado, grows along stream banks, especially in 

 canons. It is the largest oak of the State, reaching a height of 15 meters, with a 

 trunk diameter of about 7 dm. 



The bark is furrowed, rough and gray. The twigs are shghtly hairy, purplish 



or brown, becoming smooth and 

 gray. The leaves are broadly 

 obovate in outline, i to 1.5 dm. 

 long, the 5 to 9 lobes oblong 

 to triangular, rounded or ob- 

 liquely notched at the apex, the 

 sinuses broad, sometimes reach- 

 ing half-way to the midrib and 

 rounded at the bottom, the base 

 broad or cuneate-tapering; they 

 are very thin and firm, light 

 green, sparingly hairy at first, 

 soon becoming smooth and 

 slightly shining above, paler 

 and smooth except on the 

 prominent venation beneath; 

 the leaf-stalk is rather stout, about 1.5 cm. long. The fruit, ripening in the 

 autumn of the first season, is nearly sessile; nut broadly oblong, 12 to 15 mm. 

 long, blunt or depressed at the apex, embracing one half of the nut, covered by 

 ovate-lanceolate, shghtly thickened, blunt scales. 



Fig. 298. Colorado White Oak. 



61. ASHE'S OAK Quercus Margaretta Ashe 



While usually a shrub, this sometimes becomes a tree 10 meters tall. It occurs 

 in pinelands or open woods from Virginia to Florida and Alabama and is a near 

 relative of the Post Oak. 



The bark is ver}' rough, the twigs rather stout, smooth, shining and reddish 



