14. Quercus velutina Lam. (black oak, yellowbark oak)

Pl. 415 g–i; Map 1852

Plants trees to 25 m tall. Bark dark gray, divided into narrow, more or less persistent ridges, the inner bark yellow or orange. Twigs 2–4 mm wide, brown or dark brown, usually densely pubescent with branched spreading hairs when young, becoming glabrous with age. Buds 4–12 mm long, tan to light or rarely dark brown, pubescent. Petioles 25–60 mm long. Leaf blades 13–21 cm long, 11.0–16.5 cm wide, obtuse or truncate at the base, divided 40–90% of the width, the lobes 3 or 4(5) per side, the largest pair at or above midpoint; well-developed lobes 20–55 mm wide, oblong or rhombic, rarely much broadened outward, tapered to rounded apically, usually with 1 strong secondary lobe on the lower margin and a few teeth or small lobes on each margin, each with 2–5 bristles 2–7 mm long (the whole blade with 14–43 marginal bristles); the strongest secondary veins reaching the margin at the tips of the lobes and ending in bristles, others reaching toward sinuses and turning aside before reaching the margin; the upper surface usually rather shiny, with small, branched, spreading hairs scattered along the midvein and sometimes between the veins near the blade base, the undersurface green, glabrous or with 5–12-rayed, spreading hairs and inconspicuous, unbranched, appressed hairs along the main veins and scattered in patches on the blade (especially near the leaf base and the major veins), smooth or harsh-felty to the touch, the vein axils with conspicuous tufts of 6–8-rayed, stalked hairs. Acorn cups 9–13 mm long, 14–25 mm wide, covering 30–60% of the nut, hemispheric to bowl-shaped, the base prolonged, the inner surface smooth, hairy except near the rim, the outer surface with the scales thin and plane, pubescent. Nuts 11–16 mm long, 9–16 mm wide, ellipsoid to nearly cylindric, without concentric grooves around the tip. 2n=24. April–May.

Common nearly throughout the state (eastern U.S. west to Minnesota and Texas; Canada). Mesic to dry upland forests, savannas, sand savannas, margins of upland prairies, sand prairies, loess hill prairies, glades, tops of bluffs, and less commonly banks of streams and rivers; also pastures, fencerows, and roadsides.

The common form of Q. velutina, with patches of stellate hairs scattered on the undersurface of the blade (especially near the leaf base and the major veins), has been called f. missouriensis (Sarg.) Trel. The inner bark of this species yields quercitrin, a yellow compound that was once widely used as a dye. Hybrids with nine other oak species have been documented from the state, which is the largest diversity of oak hybrids in Missouri.

Most Missouri populations of Q. velutina have relatively open, sparsely branched crowns. A few populations from the northernmost tier of counties in Missouri have denser, more closely branched crowns. Such populations are found elsewhere the northern part of the range of Q. velutina, especially in the Great Lakes region. This closely branched northern race of Q. velutina has sometimes been sometimes confused with Q. ellipsoidalis (Overlease, 1975), a species that is closely related to Q. velutina (Hipp and Weber, 2008)..