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Post oak

Quercus stellata Wangenh.

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Post oak bark
Post oak buds
Post oak habit
Post oak leaves
Post oak
Post oak staminate catkins
Post oak leaves

Morphology

Trunk
Erect; bark gray to dark brown, fissures deep, ridges flat, blocky; wood light brown, hard.
Twigs
Reddish brown or yellowish brown to dark brown or gray, rigid, densely stellate-hairy; leaf scars crescent-shaped; buds brown, ovoid, .12 to .24 inch, apex obtuse, scales sparsely pubescent.
Leaves
Deciduous, alternate, simple; petiole .12 to .8 inch, pubescent; blade obovate to inversely triangular or elliptic in outline, 1.6 to 6 inches long, .8 to 4 inches wide, base attenuate to cordate, margins 1-3-lobed per side, lateral lobes oblong to ovate, spreading, distal lateral lobes and terminal lobe sometimes with 1-3 shallow lobes, terminal lobe similar in size and shape to distal laterals, sinuses extending 2/3 to 9/10 distance to midrib, lobe apex obtuse to rounded, not bristle-tipped, lower surface yellowish green, densely hairy with appressed-stellate hairs and scattered glandular hairs, upper surface shiny to dull dark green, glabrate or sparsely stellate-hairy.
Flowers
Inflorescences staminate catkins at base of new growth, 20-30-flowered, pendent, 3.2 to 4 inches; peduncle .3 to .8 inch; pedicels absent; pistillate spikes axillary from new growth, 1-3-flowered; peduncle 0 to .16 inch; pedicels absent. Flowers unisexual, more or less radially symmetric; staminate: sepals 2-6, connate, calyx lobes .05 inch; petals absent; stamens 5-8; pistillate: sepals 6, connate, calyx adnate to ovary; petals absent; pistil 1; styles 3.
Fruit
October; acorns, maturing first year; peduncle elongating to 0 to .24 inch; cup top-shaped to hemispheric, .28 to .6 × .43 to 1 inch, enclosing 1/3 to 1/2 of nut, scale apices closely appressed; nut light brown, ovoid to globose, .4 to .8 inch, glabrous or minutely pubescent; seed 1.

Ecology

Habitat
Dry, sandy to gravelly or rocky upland forests and woodlands, dry slopes, pastures.
Distribution
East 1/3 of Kansas

Additional Notes

Comments

Perhaps the most recognizable feature of Quercus stellata is its cross-shaped leaf blades, though trees in some parts of the range do not bear leaves so characteristically shaped. In Kansas, post oak is most abundant on sandy soils.

Quick Facts
Plant Type
Tree
Family
Fagaceae - Beech Family
Height
To 75 feet
Origin
Native
Last Updated
2019-02-17
Flowering Period
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Blooms: April, May