This group is characterized by having bristles or points on the leaf lobes and acorns which mature in two growing seasons and sprout in the spring after maturity. The leaves are lustrous and dark green in color on the upper surface and paler or coppery below with more or less scurfy pubescence and prominent tufts in the axils of the leaf veins. Twigs are stout and red-brown in color.
Black oak is native in the eastern and southern halves of Iowa.
It is a very common upland tree, often growing on dry ridges and southern or western slopes. Most trees in southern and east central Iowa are quite typical of the species, having large, strongly angled, densely hairy buds and acorn cups with loosely attached scales. Iowa have small, slightly angled buds that are incompletely hairy and acorn cups with tighter fitting scales. These may be geographical variants or hybrids between black and red or Hill's oak. Black oak is seldom used as an ornamental.