The leaf of black gum is variable in size and shape. It can be oval, elliptical or obovate. It is lustrous, with entire, often wavy margins. The leaf turns scarlet in autumn. The flower is very small, greenish-white in clusters at the top of a long stalk. The fruit is a black-blue, ovoid stone fruit, about 3/8 of an inch long with a thin, oily, sour flesh. There are from one to three such fruit together on a long slender stalk. The bark is dark grey and flaky when young, but it becomes furrowed with age. The twigs of this tree are are reddish-brown, usually hidden by a greyish skin. The pith is chambered with greenish partitions.