FAG ACE AE. 333 



* * Leaves or their lobes not bristle-tipped, deciduous; acorns maturing in autumn 



of first year. 

 t Leaves pinnatifid or pinnately lobed. 

 Mature leaves pale, or glaucous and glabrous beneath ; cup shallow. 



16. Q. alba. 

 Mature leaves tomentulose beneath ; cup one-third to fully as long as the acorn. 



Upper scales of the cup not awned. 



Leaves yellowish-brown tomentulose beneath ; acorn ovoid. 



17. Q. minor. 

 Leaves white-tomentulose beneath ; acorn depressed-globose. 



18. Q. lyrata. 

 Upper scales awned, forming a fringe around the acorn. 19. Q. macrocarpa. 



1 1 Leaves crenate or dentate, not lobed. 

 Fruit peduncled. 



Peduncle much longer than petioles ; leaves white-tomentulose beneath. 



20. Q. platanoides. 

 Peduncle equalling or shorter than the petioles ; leaves gray-tomentulose beneath. 

 Bark white, flaky. 21. Q. Michauxii. 



Bark close. 22. Q. Prinus. 



Fruit sessile or nearly so. 

 Tall trees. 



Leaves mostly oblong to lanceolate ; cup deep; bark close. 23. Q. acuminata. 

 Leaves obovate ; cup shallow ; bark more or less flaky. 24. Q. Alexanderi. 



Shrub or low tree ; leaves oval or obovate. 25. Q. prinoides. 



* * * Leaves entire (rarely with a few bristle-tipped lobes), evergreen. 



26. Q. Virginiana. 



1. Quercus rubra L. Red Oak. (I. F. f. 1228.) A large forest tree, the 

 bark dark gray, slightly roughened. Leaves oval or somewhat obovate, when 

 mature glabrous, or pubescent in the axils of the veins beneath, 1-2 dm. long, dull 

 green above, paler beneath, sinuses rounded, lobes triangular-lanceolate, tapering 

 from a broad base to an acuminate apex; styles spreading; cup saucer-shaped, its 

 base flat or slightly convex, 16-25 mm. broad; bracts ovate or ovate-lanceolate, 

 appressed; acorn ovoid, 2-3 cm. long, 2-4 times as long as the cup. N. S. to 

 Ont., Minn., Fla., Kans. and Tex. May-June. Acorns ripe Oct.-Nov. 



Quercus rubra runcinata A. DC. Leaf-lobes nearly entire ; acorn 1.2 cm. high. 

 Near St. Louis. Perhaps a hybrid with Q. digitata. 



2. Quercus palustris DuRoi. Swamp Oak. Pin Oak. (I. F. f. 1229.) A 

 torest tree, the lower branches deflexed; bark brown, rough when old. Leaves 

 broadly oblong or obovate, deeply pinnatifid, bright green, glabrous and shining 

 above, duller, glabrous or with tufts of hairs in the axils of the veins beneath, o. 7- 

 1.3 dm. long, the lobes oblong, lanceolate or triangular- lanceolate, divergent; styles 

 slender; cup saucer- shaped, 8-12 mm. broad, base flat, bracts triangular-ovate, 

 appressed; acorn subglobose or ovoid, 8-14 mm. high, often striate, 2-3 times as 

 long as the cup. In moist ground, Mass. to Wis., Del. and Ark. May-June. 

 Acorns ripe Sept. -Oct. 



3. Quercus Schneckii Britton. Schneck's Red Oak. (I. F. f. 1230.) A 

 forest tree, similar to the preceding species. Bark reddish-brown, with broad 

 ridges broken into plates ; leaves mostly obovate, bright green and shining above, 

 paler and with tufts of wool in the axils beneath, 0.5-1.5 dm. long, truncate or 

 broadly wedge-shaped at the base, deeply pinnatifid into 5-9 oblong or triangular 

 lobes; styles short ; cup saucer-shaped, 10-16 mm. broad, its scales appressed ; 

 acorn ovoid, 1-2.5 cm. long, 2-3 times as high as the cup. Ohio and S. Ind. to 

 Iowa, Mo., Fla. and Tex. April-May. Acorns ripe Sept.-Oct. (Q. Texana 

 Sargent, in part, not Buckley.) 



4. Quercus cocclnea Wang. Scarlet Oak. (I. F. f. 1231; acorns.) A forest 

 tree, inner bark pale reddish or gray ; foliage turning scarlet in autumn. Leaves 

 deeply pinnatifid, glabrous, bright green and shining above, paler beneath, 1-2 

 dm. long, rather thin, the lobes oblong or lanceolate, divergent or ascending, few- 

 toothed ; styles slender, recurved-spreading ; cup hemispheric or top-shaped, its 

 bracts triangular-lanceolate, mostly glabrous ; acorn ovoid, 1-2 cm. high, about 

 twice as long as the cup. In dry soil, Me. and Ont. to Minn., Fla. and Mo. May- 

 June. Acorns ripe Sept. -Oct, 



