Black walnut

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Black walnut fruit and leaves

Black walnut leaf

Black walnut buds

Black walnut leaf scar

Black walnut fruit

Black walnut fruit in winter

Black walnut

Black walnut buds

Black walnut bark

Black walnut staminate flowers

Black walnut buds

Black walnut buds

Black walnut staminate flowers

Black walnut fruit

Black walnut bark

Black walnut fruit

Black walnut pistillate flower

Morphology

Trunk

Straight, 20-60 inches in diameter; crown open, broad; branches heavy, low when tree found in the open; bark thick, dark brown to blackish, deeply furrowed into narrow, rough ridges.

Twigs

Stout, rigid, grayish-brown, downy when young; leaf scars large, shield-shaped or somewhat 3-lobed; bundle scars in 3 groups; terminal bud irregular, flattened; lateral buds smaller.

Leaves

Alternate, deciduous, pinnately-compound, 8-24 inches long; stalk stout, 2.6 to 5 inches long, pubescent; leaflets 9-23, lanceolate or narrowly egg-shaped, 1.5 to 4 inches long, .6 to 2.2 inches wide; upper surface glabrous, yellowish-green; lower surface soft-pubescent, paler; margins sharp-toothed; base rounded; tip long-tapering to point; terminal leaflet small or frequently absent.

Flowers

In May, with leaves; monoecious (male and female flowers on same tree); staminate in catkins that are solitary or in clusters, cylindrical, 2.4 to 4.8 inches long, drooping; staminate flower calyx 6-lobed; corolla absent; stamens numerous; anthers purplish; pistillate flowers solitary or 2-4 in clusters, egg-shaped, .4 to .6 inch long; calyx 4-lobed, green, velvety; corolla absent; styles and stigmas 2, yellowish-green, spreading.

Fruit

October; solitary or in clusters of 2-3; husk spherical, 1.5 to 2 inches in diameter, initially yellowish-green, later dark brown; nuts egg-shaped to spherical, 1.2 to 1.6 inch in diameter, irregularly furrowed, black; kernel edible.

Ecology

Habitat

Stream banks, bottomland woods, fertile hillsides, and shelter belts.

Distribution

Throughout Kansas, but more common in eastern 2/3.

Practical Information

Uses

Ornamental or lumber tree. Nuts edible. Native Americans used the nuts for food, fresh or stored for winter use; crushed the nuts, boiled them, and used the liquid as a beverage. The bark, roots and husks were used to make a black dye and the leaves to make a green dye. The leaves were scattered about to ward off fleas and the kernel oil was mixed with bear fat and rubbed on to repel mosquitoes. The bark was chewed for toothaches; crushed leaves were applied to ringworm; the root bark was boiled and the liquid taken to prevent dysentery. An infusion of the inner bark was taken for smallpox.

Additional Notes