The leaves of the black oak are alternately arranged on the twig and are 10-20 centimeters long with 5-7 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.
The fruits or acorns of the black oak are small and almost as wide as they are long. The upper half of the nut is covered by a cap of loose scales that often form a fringe around the acorn.
The inner bark of the black oak contains a yellow pigment called quercitron, which was sold commercially in Europe until the 1940s.