post oak

''Quercus stellata'', the post oak or iron oak, is a North American species of oak in the white oak section. It is a slow-growing oak that lives in dry areas on the edges of fields, tops of ridges also grows in poor soils, and is resistant to rot, fire, and drought. Interbreeding occurs among white oaks, thus many hybrid species combinations occur.

The species is native to the eastern and central United States, and found along the east coast from Massachusetts to Florida, and as far inland as Nebraska. It is identifiable by the rounded cross-like shape formed by the leaf lobes and hairy underside of the leaves.

Description

Post oak is a relatively small tree, typically tall and trunk in diameter, though occasional specimens reach tall and in diameter. The leaves have a very distinctive shape, with three perpendicular terminal lobes, shaped much like a Maltese cross. They are leathery, and tomentose (densely short-hairy) beneath. The branching pattern of this tree often gives it a rugged appearance. The acorns are long, and are mature in their first summer.

Similar species

Both ''Quercus stellata'' and ''Q. alba'' are in a section of ''Quercus'' called the white oaks. In the white oak section, ''Q. stellata'' is a sister taxon with ''Q. alba''. ''Q. stellata'' is sold and distributed as white oak. One identifiable difference between the two trees is that ''Q. stellata'' is 'hairy' on the underside of the leaf.Stein, John D., Denise Binion, and R. E. Acciavatti.
Field guide to native oak species of eastern North America.
(2003): 96-97.

Taxonomy

The specific epithet ''stellata'' is Latin for "star"; it is named this because the trichome hairs on the bottom of the leaves are stellate or star-shaped. Several variants of ''Q. stellata'' were named by American botanist Charles Sprague Sargent. The variety most recognised by the United States Forest Service is ''Q. stellata'' var. ''paludosa'' Sarg (delta post oak).Stransky, John J. "Quercus stellata Wangenh.--post oak.
''Silvics of North America'' 2
(1990): 738–743.

Varieties

Varieties include:
* var. ''margarettiae'' (Ashe) Sarg.
* var. ''paludosa'' Sarg.
* var. ''boyntonii'' (Beadle) Sarg.
* var. ''anomala'' Sarg.
* var. ''attenuata'' Sarg.
* var. ''araniosa'' Sarg.
* var. ''palmeri'' Sarg.
* var. ''parviloba'' Sarg.
* var. ''rufescens'' Sarg.

Hybrids

Distribution and habitat

''Q. stellata'' is found in the Southeastern United States both inland and along the coast, then in a narrow range along the coastal plain from Maryland to coastal Massachusetts, then westward to Texas, and inland to Iowa. In Texas, the Post Oak Savannah extends down to, and ends in, far northwestern Atascosa county where a fairly dense population exists. Normally found at the edge of a forest, it typically grows in dry, sandy areas, deficient of nutrients.

Ecology

''Q. stellata'' has the ability to survive fires by having thicker bark. It is useful for fire surveys where the tree rings are used to get a fire history of an area. A tree ring survey of 36 trees in Illinois provided a 226-year tree ring record that indicated that many ''Q. stellata'' persisted through annual fire return intervals of 1.44 fires/year for over 100 years.

It is used for food for deer, turkeys, squirrels, and other rodents, but because the nuts contain tannin, it is toxic to cattle.

Uses

Because of its ability to grow in dry sites, attractive crown, and strong horizontal branches, it is used in urban forestry. It is resistant to decay, so it is used for railroad ties, siding, planks, construction timbers, stair risers and treads, flooring, pulp, veneer, particle board