Fruit maturing at the end of the second season (except 22); shell of the nut silky tomentose on the inner surface; leaves or their lobes bristle-tipped. Black Oaks. Stamens usually 4—6; styles elongated, finally recurved; abortive ovules apical. Leaves deciduous in their first autumn or winter. Leaves pinnately lobed, convolute in the bud. Leaves green on both surfaces. Scales of the cup of the fruit closely appressed. Leaves usually dull on the upper surface, 7—11-lobed; cup of the fruit cup-shaped or in one variety broad and saucer-shaped, its scales thin.1. [Q. borealis] (A). Leaves lustrous. Leaves dimorphous, 5—7-lobed, axillary clusters of hairs large and prominent; cup of the fruit saucer-shaped or in one form deep cup-shaped.2. [Q. Shumardii] (A, C). Leaves similar on upper and lower branches. Cup of the fruit turbinate or deep cup-shaped. Leaves 5-lobed, the lobes usually entire, rarely furnished with tufts of axillary hairs below.3. [Q. texana] (C). Leaves 5—7-lobed, the lobes dentate, furnished with tufts of axillary hairs below.4. [Q. ellipsoidalis] (A). Cup of the fruit deep cup-shaped to turbinate; leaves 5—9-lobed, the lobes toothed.5. [Q. coccinea] (A, C). Cup of the fruit saucer-shaped. Leaves 5—9-lobed.6. [Q. palustris] (A, C). Leaves 3—5-lobed.7. [Q. georgiana] (C). Scales of the cup of the fruit more or less loosely imbricated, forming a free margin on its rim. Leaves usually 7-lobed. Winter-buds tomentose.8. [Q. velutina] (A, C). Winter-buds pubescent only at apex.9. [Q. Kelloggii] (G). Leaves usually 3—5-lobed; winter-buds rusty pubescent.10. [Q. Catesbæi] (C). Leaves whitish or grayish tomentulose below. Leaves mostly acutely 5-lobed, pale or silvery white below.11. [Q. ilicifolia] (A). Leaves often dimorphous, 3—11-lobed, the lobes often falcate.12. [Q. rubra] (A, C). Leaves broad-obovate, often abruptly dilated at the wide obscurely lobed apex. Leaves rounded or cordate at base. Lower surface of the leaves orange color or brownish, the upper scales of the cup forming with several rows a thick rim on its inner surface, often reflexed.13. [Q. marilandica] (A, C). Lower surface of the leaves pale, the erect scales on the rim of the cup in a single row.14. [Q. arkansana] (C). Leaves cuneate at base. Leaves oblong-obovate.15. [Q. nigra] (C). Leaves rhombic.16. [Q. rhombica] (C). Leaves lanceolate-oblong or lanceolate-obovate, usually entire, involute in the bud. Willow Oaks. Leaves glabrous. Leaves lanceolate to oblanceolate, deciduous in autumn.17. [Q. Phellos] (A, C). Leaves elliptic or rarely oblong-obovate, deciduous in the late winter.18. [Q. laurifolia] (C). Leaves tomentose or pubescent below, oblong-lanceolate to oblong-obovate. Leaves pale blue-green, hoary tomentose below.19. [Q. cinerea] (C). Leaves dark green, pubescent below.20. [Q. imbricaria] (A). Leaves not deciduous in the autumn, revolute in the bud (convolute in 23). Leaves mostly persistent until after the appearance of those of the following year. Leaves lanceolate, oblong-lanceolate or elliptic, pale and tomentose below.21. [Q. hypoleuca] (E, H). Leaves oval, orbicular to oblong, green and pubescent below; fruit maturing at the end of the first season.22. [Q. agrifolia] (G). Leaves persistent until their second summer or autumn. Leaves lanceolate to oval or oblong-lanceolate, entire or serrate; cup of the fruit turbinate or tubular.23. [Q. Wislizenii] (G). Leaves oval to oblong-obovate; cup of the fruit saucer-shaped or turbinate.24. [Q. myrtifolia] (C). Stamens usually 6—8; styles dilated; abortive ovules basal or lateral; leaves persistent until their third or fourth season, involute in the bud. Leaves oblong, entire, dentate, or sinuate-toothed, fulvous-tomentose and ultimately pale on the lower surface; cup of the fruit usually thick.25. [Q. chrysolepis] (G, H). Leaves oblong-lanceolate, crenate-dentate or entire, pubescent or tomentose below; cup of the fruit usually thin.26. [Q. tomentella] (G). Fruit maturing at the end of the first season; shell of the nut glabrous on the inner surface (hoary-tomentose in 27); abortive ovules basal; stamens 6—8; styles dilated; lobes of the leaves not bristle-tipped. White Oaks. Leaves mostly persistent until the appearance of those of the following year, revolute in the bud (convolute in 28). Leaves yellow-green. Fruit sessile or short-stalked. Leaves oblong-lanceolate, entire or repand-dentate; inner surface of the nut hoary tomentose.27. [Q. Emoryi] (F, H). Leaves oblong or obovate, entire, sinuate-toothed or lobed.28. [Q. dumosa] (G). Fruit long-stalked; leaves oblong, elliptic or obovate, pale, glabrous or in one form densely tomentose below.29. [Q. virginiana] (C). Leaves blue-green. Fruit usually in many-fruited long-stalked clusters; leaves broad-obovate, coarsely reticulate-venulose.30. [Q. reticulata] (H). Fruit solitary or in pairs. Cup of the fruit saucer-shaped; leaves ovate to ovate-oblong, entire.31. [Q. Toumeyi] (H). Cup of the fruit cup-shaped or hemispherical, oblong-lanceolate to broad-obovate, pubescent below.32. [Q. arizonica] (H). Cup of the fruit usually cup-shaped or turbinate. Leaves ovate, oval or obovate, usually cordate at base; fruit rather long-stalked.33. [Q. oblongifolia] (E, H). Leaves oblong to obovate, usually cuneate or rounded or cordate at base.34. [Q. Engelmannii] (G). Leaves deciduous in their first season. Leaves blue-green. Arboreous; leaves oblong, lobed, spinescent-dentate or entire, pubescent below; cup of the fruit shallow cup-shaped.35. [Q. Douglasii] (G). Arborescent or shrubby. Leaves oblong to oblong-obovate, undulate-lobed; cup of the fruit saucer-shaped to cup-shaped.36. [Q. Vaseyana] (C). Leaves oblong-obovate to elliptic or lanceolate, undulate, serrate-toothed or irregularly lobed; cup of the fruit hemispheric to cup-shaped.37. [Q. Mohriana] (C). Leaves oblong to oblong-ovate, slightly lobed or entire; cup of the fruit cup-shaped or rarely saucer-shaped.38. [Q. Laceyi] (C). Leaves yellow-green. Leaves entire or slightly lobed. Leaves different on upper and lower branches, oblong to oblong-obovate, slightly lobed or entire. Cup of the fruit cup-shaped.39. [Q. annulata] (C). Cup of the fruit shallow saucer-shaped.40. [Q. Durandii] (C). Leaves similar on upper and lower branches, entire or slightly sinuate-lobed toward the apex, oblong or oblong-obovate.41. [Q. Chapmanii] (C). Leaves more or less deeply sinuate-lobed. Leaves white-tomentulose below (sometimes green and pubescent in 43). Leaves obovate or oblong, lyrately pinnatifid or deeply sinuate-lobed; cup of the fruit fringed by the awned scales.42. [Q. macrocarpa] (A, C, F). Leaves obovate-oblong, deeply 5—9-lobed or pinnatifid; nut often inclosed in the cup.43. [Q. lyrata] (A, C). Leaves pubescent below. Leaves usually covered above with fascicled hairs, obovate, 3—5-lobed, their lobes truncate or rounded.44. [Q. stellata] (A, C). Leaves glabrous above at maturity. Leaves obovate to oblong; cup of the fruit shallow cup-shaped or slightly turbinate, its scales usually thin.45. [Q. Garryana] (B, G). Leaves oblong-obovate; cup of the fruit hemispheric, the scales often much thickened.46. [Q. utahensis] (F). Leaves oblong-obovate, deeply lobed; nut conic, elongated, inclosed for one-third its length in the cup-shaped cup.47. [Q. lobata] (G). Leaves glabrate or puberulous below, oblong to oblong-obovate.48. [Q. leptophylla] (F). Leaves glabrous below. Leaves oblong-obovate, usually 5-lobed.49. [Q. austrina] (C). Leaves oblong-obovate, obliquely pinnatifid or 3—9-lobed.50. [Q. alba] (A, C). Leaves coarsely sinuate-toothed. Chestnut Oaks. Fruit on peduncles much longer than the petioles; leaves obovate or oblong-obovate, generally sinuate-dentate or lobed, pubescent, and usually hoary on the lower surface.51. [Q. bicolor] (C). Fruit on peduncles about as long or shorter than the petioles. Leaves obovate or oblong-obovate, cuneate or rounded at the broad or narrow base, tomentose or pubescent and often silvery white below.52. [Q. Prinus] (A, C). Leaves obovate or oblong to lanceolate, acuminate, with rounded or acute teeth.53. [Q. montana] (A, C). Fruit sessile or nearly so; leaves oblong to lanceolate, acute or acuminate or broadly obovate, puberulous and pale, often silvery white on the lower surface.54. [Q. Muehlenbergii] (A, C).
1. [Quercus borealis] Michx. Red Oak.
Leaves obovate or oblong, acute or acuminate, abruptly or gradually cuneate or rounded at the broad or narrow base, usually divided about half way to the midrib by wide oblique sinuses rounded at the bottom into 11 or sometimes into 7 or 9 acute oblique ovate lobes tapering from broad bases and mostly sinuately 3-toothed at apex with elongated bristle-pointed teeth, or sometimes oblong-obovate, gradually narrowed and cuneate at base, and sinuately lobed with broad acute usually entire or slightly dentate lobes, when they unfold pink, covered with soft silky pale pubescence on the upper surface and below with thick white tomentum, soon glabrous, at maturity thin and firm, dark green, dull and glabrous above, pale yellow-green, glabrous or rarely puberulous and sometimes furnished with small tufts of rusty hairs in the axils of the veins below, 5′—9′ long, 4′—6′ wide; falling early in the autumn after turning dull or sometimes bright orange color or brown; petioles stout, yellow or red, 1′—2′ in length. Flowers: staminate in pubescent aments 4′—5′ long; calyx divided into 4 or 5 narrow ovate rounded lobes shorter than the stamens; pistillate on short glabrous peduncles, their involucral scales broadly ovate, dark reddish brown, shorter than the conspicuous linear acute bract of the flower and as long as the lanceolate acute calyx-lobes; stigmas bright green. Fruit solitary or in pairs, sessile or short-stalked, ovoid, gradually narrowed and acute at apex or cylindric and rounded at apex, pale brown, lustrous, more or less tomentose toward the ends, ½′—1′ long; ½′—¾′ in diameter; cup cup-shaped, puberulous on the inner surface, covered with small closely appressed ovate acute red-brown pubescent scales slightly thickened on the back toward the base of the cup, with a thin dark-colored tip and margins.
A tree usually not more than 60°—70° high, with a trunk 2°—3° in diameter, often much smaller, stout branches forming a narrow head, and slender lustrous branchlets light green and covered with pale scurfy pubescence when they first appear, dark red during their first winter and ultimately dark brown. Winter-buds ovoid, gradually narrowed to the acute apex, about ¼′ long, with thin ovate acute light chestnut-brown scales. Bark on young stems and on the upper part of the limbs of old trees 1′—1½′ thick, dark brown tinged with red and divided into small thick appressed plates scaly on the surface. Wood heavy, hard, strong, close-grained, light reddish brown, with thin lighter-colored sapwood; used in construction, for the interior finish of houses, and in furniture.
Distribution. Nova Scotia and New Brunswick, through Quebec to southern Ontario, and southward to northern New England, western New York, northern Pennsylvania (Presque Isle, Erie County), northern Michigan, southeastern Wisconsin, central Minnesota, central Iowa (Winneshick County), and on the Appalachian Mountains of North Carolina at altitudes of about 4000°. Passing with many intermediate forms differing in the size of the nut and in the depth of the cup into
Quercus borealis var. maxima Ashe. Red Oak.
Quercus rubra Du Roi, not L.
Fruit solitary or in pairs, sessile or short-stalked; nut ovoid to slightly obovoid, gradually narrowed and rounded at apex, slightly narrowed at base, usually 1′—1¼′ long and ½′—⅔′ thick, occasionally not more than ⅔′ long and thick, inclosed only at the base in a thick saucer-shaped cup.