blackjack oak
Quercus marilandica

Secondary Names:

Leaf Type: Deciduous
Texas Native:
Tree Description:

A medium to large tree that can reach a height of 60 feet and a diameter of 16" to 24", but is usually much smaller. Its stiff, drooping branches form an irregular, dense crown that often contains many persistent dead twigs or branches.

Range/Site Description:

Occurs in East and Central Texas, as far west as Callahan county, on dry or poorly drained, gravelly clays, or sandy upland soils where few other forest trees thrive.


Simple, alternate, 4" to 10" long and 3" to 5" wide, strongly obovate, usually with three main bristle-tipped lobes on the upper half of the leaf, the bottom half narrowing abruptly to the petiole. Leaves are leathery, dark green and glossy on top, lighter and tawny-pubescent below.


Separate male and female flowers appear in spring on the same tree. Male flowers borne on a yellowish catkin 2" to 4" long; the less conspicuous female flowers are reddish in color.


An acorn, taking two years to mature, about 0.75" long, yellow-brown and often striped, enclosed for one-half to two-thirds its length in a thick, light-brown cup.


Black or dark gray, very rough and breaking into thick, squarish blocks on older trunks.


Heavy, hard and strong. It is used for firewood, posts, and is made into charcoal.

Similar Species:

Water oak (Quercus nigra) has similar three-lobed leaves that are less than 4" long.

Interesting Facts:

Several forms of the species with smaller leaves occur in Central Texas on limestone soils and bluffs.

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