58 FOUNDATIONS OF BOTANY 



B. Fruit annual ; leaves not bristle-tipped, though often 

 nmcronate. 



6. Q. alba, L. WHITE OAK. A large tree with light gray bark. 

 Leaves obovate-oblong, 3-9-lobed, lobes rounded and mostly entire, 

 bright green above, paler below, short-petioled. Cup hemispherical, 

 scales rough, woolly when young, but becoming smooth with age ; 

 acorn oblong-ovate, about 1 in. long. Common in damp soil ; wood 

 strong and durable ; one of the most valuable timber trees.* 



7. Q. stellata, Wang. POST OAK. A tree of medium size with 

 rough gray bark. Leaves broadly obovate, deeply lyrate-pinnatified 

 into 5-7 rounded, divergent lobes, upper lobes much the longer, 

 smooth above, yellowish-downy beneath, petioles about 1 in. long. 

 Cup hemispherical, nearly sessile ; acorn ovoid, 2-3 times as long as 

 the cup. On dry soil ; wood hard and valuable. 



8. Q. macrocarpa, Michx. BUR OAK. A medium-sized to very 

 large tree, with roughish gray bark. Leaves obovate or oblong, 

 lyrately and deeply sinuate-lobed, smooth above, pale or downy 

 beneath. Cup very deep and thick, abundantly fringed about the 

 margin, | in. to 2 in. in diameter. Acorn, half or more [sometimes 

 entirely] enclosed by the cup. Reaches its full size only on rich 

 bottom lands S. and W., where it becomes one of the finest timber 

 oaks. Wood very hard and heavy. 



9. Q. lyrata, Walt. SWAMP OAK. A large tree with gray or 

 reddish bark. Leaves obovate-oblong, deeply pinnatifid, lobes 

 narrow, often toothed, thin, smooth above, white, densely woolly 

 beneath. Cup round-ovate, scales cuspidate, enclosing nearly the 

 whole of the depressed-globose acorn. On wet soil ; wood strong 

 and very durable.* 



10. Q. prinus, L. SWAMP CHESTNUT OAK. A large tree with 

 brown, ridged bark. Leaves oblong or oblong-lanceolate, rather ob- 

 tuse, crenately toothed, minutely downy beneath, petioles slender, 

 about 1 in. long. Cup hemispherical, peduncles longer than the 

 petioles, scales acute, tubercular, appressed ; acorn oblong, acute, 

 1 in. or less in length, edible. Common on low ground. Wood 

 strong and valuable.* 



11. Q.- Muhlenbergii, Engelm. YELLOW CHESTNUT OAK. A 

 tree of medium or large size with gray bark. Leaves oblong or 

 oblanceolate, usually acute at the apex and obtuse or rounded at the 

 base, coarsely and evenly toothed ; veins straight, impressed above 

 and prominent beneath ; petioles slender. Cup hemispherical, sessile 

 or short-peduncled, with flat scales, ^ in. broad, enclosing about half 

 the ovoid acorn, which is f-f in. long. Common on dry soil, wood 

 close-grained, durable, and valuable. 



12. Q. virginiana, Mill. LIVE OAK. A large tree with rough 



