A relatively small tree, reaching a height of 65 to 80 feet and a diameter of 35 inches. Black oak is well known to readily hybridize with other members of the red oak group of oaks being one parent in at least a dozen different named hybrids. Young leaves are densely pubescent. The leaves of the black oak are alternately arranged on the twig and are 4 to 8 inches long with 5 to -7 bristle tipped lobes separated by deep U-shaped notches. The upper surface of the leaf is a shiny deep green, the lower is yellowish-brown. There are also stellate hairs on the underside of the leaf that grow in clumps. Sun leaves have very deep u-shaped sinuses. The buds are velvety and covered in white hair. The fruits or acorns of the black oak are medium-sized and broadly rounded. The cap is large and covers almost half of the nut.
In southern New England, black oak grows on cool, moist soils. Elsewhere it occurs on warm, moist soils. Black oak grows on all aspects and slope positions. It grows best in coves and on middle and lower slopes with northerly and easterly aspects.