Bur Oak

Tree Description:

A large tree of the prairies reaching a height of 80 feet or more and a trunk diameter of 5 feet, with a short body and heavy branches that form an open, spreading crown of dark green foliage.

Range/Site Description:

Occurs on limestone soils in Central Texas as far west as Tom Green county, often on rich bottomlands along streams or hillsides and banks along spring-fed rivers. Also planted widely as a landscape tree throughout Texas.

Leaf:

Simple, alternate, 6" to 12" long and 3" to 6" wide, with 5 to 9 highly variable lobes that lack bristle-tips; lobes are divided by at least one pair of very deep sinuses, and the upper one-third of the leaf typically has a roughly-toothed or weakly-lobed margin.

Flower:

Separate male and female flowers appear in spring on the same tree. Male flowers borne on a yellowish catkin 4" to 6" long; inconspicuous female flowers reddish in color.

Fruit:

An acorn, requiring a single season to mature, 1" to 2" long, ovoid, set deeply in a mossy-fringed cup that gives the species its common name.

Bark:

Twigs and branches are thick, developing conspicuous corky ridges after the second year; bark is light gray, rough and breaks into small, narrow flakes on young trees, then develops very thick bark with deep fissures and narrow plates.

Wood:

Heavy, hard, strong, tough and durable; used for lumber, crossties, and fuelwood.

Similar Species:

White oak (Quercus alba) is found in East Texas and has smaller acorns without a fringed cup.

Interesting Facts:

Acorns are prized by wildlife and can be used to make a coarse flour.