Quercus palustris

The pin oak is in the red oak group (Lobatae) in the beech or Fagaceae family, and is mainly native to southern Ontario and the eastern and central United States from Connecticut west to eastern Kansas, south to Georgia and west to eastern Oklahoma and Kansas. Pin oak is pyramidal when young; the crown eventually becomes narrowly domed with slender lower branches that droop near the tips. These are called the "pins".

Pin oak is one of the most commonly used landscaping oaks in its native range due to its ease of transplanting, relatively fast growth, and tolerance of pollution.

• Leaves are alternate, simple, with sinuses which are typically u-shaped and extremely deep-cut; sinus area is about equal to the actual leaf area. The leaf is mostly hairless, except for a very characteristic tuft of pale orange-brown down on the lower surface where each lobe vein joins the central vein. Fall colour is scarlet, with leaves persisting dried on the trees into winter.
• Species is monoecious. Males are on slender, drooping yellow-green catkins; females are reddish-green on short spikes in new leaf axils, both appearing in the spring.
• Fruit is an acorn 1.3 cm long, striated, round but flattened at the cap; cap is thin, saucer-like. Maturation takes 2 years.
• Twigs are slender, red-brown, with multiple small, pointed terminal buds.