Post oak is a native tree and an indicator of the presence of other oaks and pine trees. In deep sands, post oak is often a shrub mixed with other shrub oaks, but in more nutrient-enriched soils, post oaks are large and very stable trees, which can be found in high numbers. Post oak is slow growing; however, they can live up to 500 years and at maturity can be as large as 50 feet in height. Its leaves are often leathery and 3-5 lobes are usually arranged so that they resemble a Christian cross. Such leaves are often shiny above and gray or yellowish-hairy beneath are 3-8 inches in length. The bark of such trees is brownish, and broken by long shallow cracks and often divided into rectangular blocks. The acorn cups are bowl-shaped and cover 1/3 to ½ of the acorn.

Post oak is most commonly used for fence posts, but can also be used for railroad crossties, furniture, lumber, and fuel. Oak leaves are eaten by white-tailed deer and livestock and the acorns are eaten by white-tailed deer, small mammals, and some birds. However, tannic acid poisoning may be a problem if eaten by cattle and can cause emaciation, edema, and mucous and/or blood in the feces.