42. Black Walnut

(Juglans nigra)

Family: Juglandaceae


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On the lawn south of Denny Hall by the stone bench erected by the Class of 1915 is a stately Black Walnut tree. Across the path from it is the largest pine on campus, a Western White Pine. We've all eaten walnuts, but black walnuts possess zestier flavor and are harder to crack than the nuts of other walnut species. They grow on enormous trees, native in much of the United States, but not the Pacific Northwest.  The wood is supreme in its fine grain, lovely dark color, and hardness. Besides the food and wood, the trees serve as excellent long lived shade trees.


Black walnut trees have insect repelling qualities and the leaves and husks have been used to repel fleas, flies, and bedbugs. The roots and leaves contain chemicals that suppress the growth of other plants and these chemicals are washed off the leaves by the rain, creating a unique understory plant assemblage. Black walnut can be added to a compost pile to speed bacterial activity and decomposition. The nut casings contain a dark black-brown dye and tannins which act as a mordant, a chemical that helps fix a dye.

[Leaves and blossoms of Black Walnut]

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