Red Oak 



281 



53. Q. tiMcrocarpa. 



54. Q. lyrata. 



Leaves obovate; bark flaky. 48. Q. Alexanderi. 



Acorns manifestly stalked (short-stalked in no. 50). 

 Peduncles shorter than the petioles or about as long. 

 Bark dose, deeply furrowed; leaves gray tomentose 



beneath. 49. Q. Prinus. 



Bark flaky. 

 Leaves smooth; Texan tree. 50. Q. Brayi. 



Leaves densely hairy beneath. 51. Q. Michauxii. 



Peduncles much longer than the petioles. 52. Q. bicolor. 



Leaves deeply lobed. 

 Leaves hairy, at least on the veins beneath, even when old. 

 Upper scales of the cup awned, forming a fringe around 



the rim of cup. 

 Upjjer scales of the cup not awned. 

 Acorn mostly broader than high; nut mostly immersed 

 in the cup; leaves lyrate, usually white-tomentu- 

 lose beneath. 



Acorn longer than broad; nut not more than half 

 immersed in cup. 

 Western trees. 



Large trees of the Pacific states. 

 Nut conic and acute; cup-scales thickened. 

 Mainland tree; leaves deeply lobed; cup 



shallow. 55. Q. lobata. 



Island tree; leaves not deeply lobed; cup 

 deep. 56. Q. MacDonaldi. 



Nut ovoid or obovoid-oblong; cup-scales thin. 57. Q. Garryana. 

 Small trees or shrubs of the Rocky mountain 

 region. 

 Mature leaves velvety beneath. 

 Cup-scales thin. 58. Q. suhmollis. 



Cup-scales corky-thickened. 59. Q. utahensis. 



Mature leaves not velvety beneath, thin. 60. Q. leptophylla. 



Eastern trees. 

 Leaves with rounded upper lobes; cup 11 to 14 

 mm. broad; southern tree or shrub. 61. Q. Margaretta. 



• Leaves with truncate or emarginate upper lobes; 



cup 15 to 20 mm. broad; eastern tree. 62. Q. stellata. 



Leaves smooth and pale beneath when old; cup shallow. 63. Q. alba. 



I. RED OAK — Quercus rubra Linnaus 



This well-known tree extends from Nova Scotia to Minnesota and Kansas, 

 southward to Florida and Kansas, reaching its greatest development in the region 

 between the Great Lakes and the Ohio River. Its maximum height is 50 meters, 

 with a trunk diameter of 1.5 m. It is also called Yellow oak, Black oak, Leopard 

 oak, and Spanish oak. 



The branches are stout and somewhat spreading, forming a narrow, round- 

 topped head, or in the open they are widely spreading and form a broad, round 



