Black Walnut

Black Walnuts (Juglans nigra)
Probably the most familiar of the walnuts, the native Black Walnut trees grow from 75 to 100 feet at maturity, their large canopies typically spreading as wide as the tree is tall. Trunks of mature Black Walnut trees measure 2 to 4 feet in diameter, sometimes to 6 feet. They grow straight and branchless to nearly 2/3 the distance from the ground. They matures in about 150 years and are capable of living for 250 years.

Black Walnut trees are deciduous, losing their foliage around mid-September each year. Their coarse leaves are composed of rows of leaflets growing opposite each other along both sides of a stem that may be from 12 to 24 inches long. Anywhere from 13 to 23 pointed leaflets, each 3 to 5 inches long and 1 to 1/2 inches wide, appear on each stem. They are yellowish-green when they unfurl in late spring and remain this color until they turn a dull yellow in the fall. They have fuzzy undersides, and a noticeable odor when they are bruised.

On all walnut trees, male and female flowers grow on the same tree. Though the female ones are inconspicuous, the male flowers appear as 4-inch long, drooping spikes in late spring just as the leaves emerge. They are yellow-green. By late summer, hard-shelled nuts measuring about 2 inches in diameter form inside protective husks. Initially green, the husks turn black as they mature. When they break open, they release the hard, ridged nut within. The nut is used in cooking and is eaten by small mammals in the wild.

Black Walnut Choices
Laciniata has finely divided leaflets that impart a fernlike texture.

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