Lower, usually dead, limbs droop, middle limbs are horizontal, and the top limbs slant upward. This branching habit is also characteristic of the shingle and willow oaks. In silhouette, immature pin oaks have conical shapes. The numerous limbs make small pin knots in the lumber. Pin oaks acorns have vertical stripes with light brown alternating with greenish browns on the fresh acorns.
Acorns are nearly hemispherical in shape and are enclosed at the base in a shallow cup.
Since it grows near water, often in pure stands, pin oak acorns are important duck foods. Squirrels, deer and even quail and blue jays relish these nutritious acorns. Biologists recommend pin oak planting in duck management areas. Leaves of this tree are more deeply lobed and more sharply pointed than any other oak. They are four to six inches long and two to four inches wide.