7. Q. Prìnus, L. (Chestnut-Oak.) Leaves thick, varying, obovate or oblong to lanceolate, sometimes acuminate, with an obtuse or acute base, undulately crenate-toothed, pale and minutely downy beneath, the main primary ribs 10–16 pairs, straight, prominent beneath; fruiting peduncles shorter than the petioles, often very short; cup thick (6–12´´ wide), mostly tuberculate with hard and stout scales; acorn large (sometimes 1–1¼´ long). (Incl. var. monticola, Michx.)—Rocky banks and hillsides, E. Mass. to N. Y. and Ont., and south in the mountains to N. Ala. A large tree, with thick and deeply furrowed bark, rich in tannin.
8. Q. Muhlenbérgii, Engelm. (Yellow Oak. Chestnut-Oak.) Leaves (5–7´ long) slender-petioled, often oblong or even lanceolate, usually acute or pointed, mostly obtuse or roundish at base, almost equably and rather sharply toothed; cup subsessile, shallow, thin, of small appressed scales, 5–7´´ broad; acorn globose or obovate, 7–9´´ long. (Q. Prinus, var. acuminata, Michx.)—Dry hillsides and rich bottoms, Mass. to Del., along the mountains to N. Ala., west to Minn., E. Neb., and Tex.—Leaves more like those of the Chestnut than any other; the primary veins very straight, impressed above, prominent beneath. A tall tree, with thin flaky bark.
9. Q. prinoìdes, Willd. Like the last, but of low stature (usually 2–4° high), with smaller more undulate leaves on shorter petioles (3–6´´ long), and deeper cups with more tumid scales. (Q. Prinus, var. humilis, Marsh.)—Same range as last. Apparently quite distinct at the east, where it is very low, but running into Q. Muhlenbergii at the far west.
[*][*][*] Leaves coriaceous, evergreen, entire or rarely spiny-toothed.—Live Oaks.
10. Q. vìrens, Ait. (Live Oak.) Leaves small, oblong or elliptical, hoary beneath as well as the branchlets; peduncle usually conspicuous, 1–3-fruited; cup top-shaped; acorn oblong; cotyledons completely united into one mass.—Along the coast from Va. to Fla. and Tex. Becoming a large tree at the south, and formerly extensively used in ship-building.
§ 2. MELANOBÁLANUS. Bark dark, furrowed; leaves deciduous, their lobes and teeth acute and bristle-pointed (at least in youth); stamens mostly 4–6; cup-scales membranaceous; styles long and spreading; abortive ovules near the top of the perfect seed; inner surface of nut tomentose; fruit maturing the second year, sessile or on short thick peduncles; wood porous and brittle.—Black Oaks.
[*] Leaves pinnatifid or lobed, slender-petioled, not coriaceous, the lobes or teeth conspicuously bristle-pointed.
[+] Mature leaves glabrous on both sides or nearly so, oval, oblong or somewhat obovate in outline, from moderately sinuate-pinnatifid to deeply pinnatifid, turning various shades of red or crimson in late autumn; large trees, with reddish coarse-grained wood; species closely related and apparently readily hybridizing.
11. Q. rùbra, L. (Red Oak.) Cup saucer-shaped or flat, with a narrow raised border (9–12´´ in diameter), of rather fine closely appressed scales, sessile or on a very short and abrupt narrow stalk or neck, very much shorter than the oblong-ovoid or ellipsoidal acorn, which is 1´ or less in length; leaves rather thin, turning dark red after frost, moderately (rarely very deeply) pinnatifid, the lobes acuminate from a broad base, with a few coarse teeth; bark of trunk dark gray, smoothish.—Common both in rich and poor soil, westward to E. Minn. and E. Kan. Timber coarse and poor.—Var. runcinàta, A. DC., is a form with regular nearly entire lobes and the fruit nearly a half smaller; found near St. Louis.
12. Q. coccínea, Wang. (Scarlet Oak.) Cup top-shaped, or hemispherical with a conical base (7–9´´ broad), coarsely scaly, covering half or more of the broadly or globular-ovoid acorn, the scales somewhat appressed and glabrate, or in western localities yellowish-canescent and squarrose as in var. tinctoria; leaves in the ordinary forms, at least on full-grown trees, bright green, shining above, turning red in autumn, deeply pinnatifid, the slender lobes divergent and sparingly cut-toothed; buds small; acorns 6–9´´ long; bark of the trunk gray, the interior reddish.—Moist or dry soil; common, from S. Maine to Del., Minn., N. Mo., and south in the mountains.