DICOTYLEDONS. 58 



1. Q. RUBRA L. Red Oak. A large tree; leaves oval or 

 obovate, green above, pale and slightly pubescent beneath, sinuses 

 shallow and rounded, lobes 8-12, acuminate; petioles long; cup 

 saucer-shaped, with fine scales ; acorn ovate or oblong, about 1 

 in. long. April-^NIay. Common ; wood not valuable ; leaves turn- 

 ing red after frost and often remaining on the tree through the 

 winter. 



2. Q. VELUTiNA Lam. Black Oak. A large tree with rough, 

 dark brown outer bark and thick, bright yellow inner bark; leaves 

 broadly oval, usually divided more than halfway to the mid-rib, sinuses 

 rounded ; lobes about 7, sharply toothed at the apex, smooth above, 

 usually pubescent on the veins beneath ; cup hemispherical or top- 

 shaped, with coarse scales, short-peduncled, enclosing about half the 

 roundish acorn. April-May. Common ; wood not valuable, but the 

 inner bark used for tanning and dyeing. 



3. Q. DiGiTATA (Marsh) Sudw. Spanish Oak. A small or 

 medium-sized tree wdth leaves 3-5-lobed at the apex, obtuse or 

 rounded at the base, grayish downy beneath, lobes lanceolate and 

 often falcate, sparingly cut-toothed ; cup top-shaped, with coarse 

 scales, enclosing about half the nearly globose acorn. April-May. 

 Common in dry woods. Foliage quite variable in outline and lob- 

 ing ; bark valuable for tanning. 



4. Q. NIGRA L. Black-jack Oak. A small tree ; leaves obovate, 

 usually with three rounded lobes at the apex, the lobes bristle-pointed, 

 rounded, or slightly cordate at the base, rusty-pubescent beneath, 

 shining above, coriaceous, short-petioled ; cup top-shaped, short-piMlun- 

 cled, with coarse and truncate scales, enclosing about one-third of 

 the ol)long-ovate acorn. April-]\Iay. An almost worthless tree, its 

 presence indicating a thin and sterile soil. 



5. Q. PiiELLos L. Willow Oak. A tree of medium si/e, 

 leaves lanceolate or elliptical, scurfy when young and becoming 

 smooth with age; very short-petioled; cup shallow, sessile; acorn 

 subglobose. March-April. A\'«'t soil ; often planted for sIkuIc. 



1). P'niit iininuil ; leaves not bristle tipped, though often 

 mueronatf. 



0. Q. ALiJA L. White Oak. A largo tree with light gray bark ; 

 leaves obovate-oblong, ^-D-lobed, lobes rounded and mostly entire, 

 bright green above, jialer below, short-ix'tioled ; cuj) hemisj)herical, 

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

 acorn oblong-ovate, iibout 1 in. long. March-April. Common in 

 damp soil; wood strong and durable; one of tlie most valuable 

 timber trees. 



