QUERCUS 



77 



e. Buds globose or nearly so; 

 bud- scales glabrous ;twigs 

 reddish 



e. Buds obtuse to somewhat 

 acute, often angled, whitish- 

 pubescent near the apex; 

 twigs reddish-brown 



d. Twigs dull, yellowish-brown 



6. Buds and twigs glabrous 

 e. Buds and twigs more or 

 less tomentose 



f. Buds about 1. 5 mm. 



long; twigs slender 

 f. Buds about 3 mm. long; 



twigs moderate 



1. Q. alba 



12. Q. coccinea 



5. Q. bicolor 



16. Q. ilicifolia 



g. Acorn 2. 5-3. 5 cm. 

 long 



h. Cup of the acorn 

 prominently fringed 

 on the margin 



h. Cup of the acorn 

 not fringed 



g. Acorn about 12 mm. 

 long 



a. Leaves evergreen 



4. Q. macrocarpa 

 3. Q. lyrata 



2. Q. stellata 

 9. O. virginiana 



1. Q. alba L. White Oak . A tree ^5-35 m. high, 1-2 m. in 

 diameter; bark gray, rough; twigs gray or purple, often glaucous; 

 buds deep-brown, medium-sized, subglobose or ellipsoid, nearly 

 or quite glabrous, about 5 mm. long; stipules glaucous; acorn ovoid 

 or ellipsoid, 2-3 cm. long, the cup hemispherical, warty, much 

 shorter than the nut. Rich woods, Maine to Minnesota, south to 

 Florida and Texas (Fig. 64). ^ 



2. q^ stellata Wang. Post Oak . A tree 15-25 m. high, 6-9 

 dm. in diameter, with rough gray bark; buds ovoid or conical- 

 ovoid, dull, silky, 3 mm. long; twigs yellow-scurfy; acorn 1-2 cm. 

 long. Sterile soil, Massachusetts to Illinois and Kansas, south to 

 Florida and Texas (Fig. 65). 



