Black Walnut (Juglans nigra)

Black Walnut – Valuable Timber and Nut Tree with Allelopathic Roots

Juglans nigra, the Black Walnut, is a large, deciduous tree native to eastern North America, prized for its high-quality, dark heartwood and edible nuts. It has large, pinnately compound leaves and produces round, green-husked nuts that stain hands black. The roots release juglone, a chemical that inhibits the growth of many nearby plants (allelopathy), making underplanting challenging. It prefers deep, moist, well-drained soils and full sun.

Taxonomic Details