SUMMER KEY TO THE SPECIES OF QUERCUS 



a. Leaves deeply cut or lobed. 



b. Leaf-lobes acute, bristle-tipped; fruit maturing in the 

 second season. 



c. Lower surface of leaves more or less pubescent. 



d. Leaf-lobes usually 7; buds hoary-tomentose ; bark of 



trunk deeply furrowed and scaly; inner bark yellow; 



cup-scales of acorn hoary-pubescent; nut ovoid; 



large tree, common in Michigan. . .Q. velutina, p. 117. 



dd. Leaf-lobes usually 3 (at apex of the leaf only) ; buds 



rusty-hairy; bark of trunk divided into nearly square 



plates; inner bark not yellow; cup-scales of acorn 



rusty-tomentose ; nut subglobose ; shrubby tree, rare 



in Michigan Q. marilandica, p. 1 19. 



cc. Lower surface of leaves glabrous or nearly so. 



d. Cup of acorn top-shaped or cup-shaped, inclosing one- 

 third to one-half of the nut. 



e. Kernel of nut yellow; buds glabrous, lustrous, 

 slightly angular ; inner bark of trunk yellow ; trunk 

 provided with pins or stubs of dead branches near 



the ground Q. ellipsoidalis, p. 115. 



ee. Kernel of nut whitish ; buds pubescent above the 

 middle, not angular; inner bark of trunk red; trunk 

 not provided with pins or stubs of branches near 



the ground Q. coccinea, p. 113. 



dd. Cup of acorn saucer-shaped, inclosing only the base 



of the nut. 



e. Upper surface of leaves usually lustrous, especially 

 on the lower branches; lowermost branches of trees 

 growing in the open drooping nearly to the ground ; 



nut about l / 2 inch long Q. palustris, p. in. 



96 



