Overcup oak

Quercus bicolor Willdenow var. lyrata (Walter) Dippel

Trees , deciduous, to 20 m. Bark light gray, tinged with red, with thick plates underlying scales. Twigs grayish or reddish, (2-)3(-4) mm diam., villous, soon glabrate. Buds 3 mm, gray-puberulent. Leaves: petiole 8-20(-25) mm. Leaf blade obovate or broadly obovate, 100-160(-200) × 50-100(-120) mm, base narrowly cuneate to acute, margins moderately to deeply lobed, lobes somewhat to sharply angular or spatulate, often with 2-3 teeth, sinuses nearly to midrib, secondary veins arched, divergent, (3-)5-7 on each side, apex broadly rounded or ovate; surfaces abaxially light green or somewhat glaucous, tomentose, tomentum persisting or soon falling, adaxially dark green or dull gray, sparsely puberulent to glabrate. Acorns 1-2 on axillary peduncles to 40 mm; cup goblet-shaped, burlike, or spheroid, 15-20 mm deep × 20-30 mm wide, usually completely enclosing nut or merely apex visible, rarely enclosing only 1/2 nut, orifice smaller than nut diameter, often splitting irregularly at maturity, scales closely appressed, especially about margin, laterally connate, broadly triangular, keeled-tuberculate, finely grayish tomentose; nut light brown or grayish, ovoid-ellipsoid or oblong, (15-)25-50 × (10-)20-40 mm, finely puberulent or floccose. Cotyledons distinct.

Flowering spring. Bottoms, lowlands, wet forest, streamside forests, swamp forests, periodically inundated areas; 0-200 m; Ala., Ark., Del., Fla., Ga., Ill., Ind., Iowa, Ky., La., Md., Miss., Mo., N.J., N.C., Okla., S.C., Tenn., Tex., Va.

The large acorns with hardened cups that enclose all or most of the nut are diagnostic.