The Post Oak is a member of the white oak group. The tree is large (70 feet) with a bole diameter of more than a foot. The trunk has long brown furrows and rectangular blocks. Leaves are five to eight inches long and shiny, leathery on top with gray, brown hairs underneath. There are three to five lobes evenly distributed to generally form a cross. The acorns are more than an half-inch long with large bowl-shaped caps. Twigs have blunt,straight buds. Buds and twigs have gray hairs.

The growing region is from Texas to Virginia. Oak is a hardwood providing a major portion of the annual lumber in the United States. Oak trees are generally slow-growing and long-lived and tend to be relatively resistant to diseases and insects. Tannin is a major produce from oak bark.