42. Quercus muehlenbergii Engelmann, Trans. Acad. Sci. St. Louis. 3: 391. 1887.
Chinkapin oak, chinquapin oak, yellow chestnut oak
Quercus acuminata (Michaux) Sargent; Q. brayi Small; Q. prinus Linnaeus var. acuminata Michaux
Trees , deciduous, moderate to large, to 30 m, occasionally large shrubs (ca. 3 m) on drier sites. Bark gray, thin, flaky to papery. Twigs brownish, 1.5-3(-4) mm diam., sparsely fine-pubescent, soon becoming glabrate, graying in 2d year. Buds brown to red-brown, subrotund to broadly ovoid, 20-40 × (10-)15-25 mm, apex rounded, very sparsely pubescent. Leaves: petiole (7-)10-30(-37) mm. Leaf blade usually obovate, sometimes lanceolate to oblanceolate, (32-)50-150(-210) × (10-)40-80(-106) mm, leathery, base truncate to cuneate, margins regularly undulate, toothed or shallow-lobed, teeth or lobes rounded, or acute-acuminate, often strongly antrorse, secondary veins usually (9-)10-14(-16) on each side, ± parallel, apex short-acute to acuminate or apiculate; surfaces abaxially glaucous or light green, appearing glabrate but with scattered or crowded minute, appressed, symmetric, 6-10-rayed stellate hairs, adaxially lustrous dark green, glabrate. Acorns 1-2, subsessile or on axillary peduncle to 8 mm; cup hemispheric or shallowly cupped, 4-12 mm deep × 8-22 mm wide, enclosing 1/4-1/2 nut, base rounded, margin usually thin, scales closely appressed, moderately to prominently tuberculate, uniformly short gray-pubescent; nut light brown, oblong to ovoid, (13-)15-20(-28) × l0-13(-16) mm. Cotyledons distinct. 2 n = 24.
Flowering late winter-spring. Mixed deciduous forest, woodlands and thickets, sometimes restricted to n slopes and riparian habitats in w parts of range, limestone and calcareous soils, rarely on other substrates; 0-2300 m; Ont.; Ala., Ark., Conn., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Mex., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Tex., Vt., Va., W.Va., Wis.; Mexico (Coahuila, Nuevo León, Hidalgo, and Tamaulipas).
Shrubby forms of Quercus muehlenbergii are difficult to distinguish from Quercus prinoides , but Q . muehlenbergii does not spread clonally or produce acorns on small shrubs as does Q . prinoides . The edaphic preferences of these two species are distinctive, with Q . muehlenbergii never far from limestone substrates and Q . prinoides occurring mostly on dry shales and deep sands. Populations of Q . muehlenbergii from the southwest part of its range, on the Edwards Plateau of Texas and westward, sometimes are segregated as Q . brayi Small, but the variation appears to be clinal with inconsistent differences. Distributed from Hidalgo, Mexico to Maine, Q . muehlenbergii is one of the most widespread species of temperate North American trees.
The Delaware-Ontario prepared infusions from the bark of Quercus muehlenbergii to stop vomiting (D. E. Moerman 1986).