Black Walnut
Juglans nigra · Deciduous Broadleaf Hardwood
Plant Family
Juglandaceae
Tree Category
Nut and Timber Tree
Variety / Cultivar
Standard species (wild type)
Hardiness Zones
USDA Hardiness Zones 4 through 9
About This Tree
A large, stately forest tree often featuring a long, straight trunk and a high, spreading, open crown. Known for its slow-to-moderate growth rate and highly prized dark heartwood.
Leaf Characteristics
Pinnately compound, 12 to 24 inches long, consisting of 15 to 23 leaflets. Leaflets are ovate-lanceolate with serrated margins; medium green color turning clear yellow in autumn.
Bark Characteristics
Dark grey to blackish in color with deep, diamond-shaped furrows and thick, interlacing ridges on mature specimens.
Growing Information
Origin Region
Central and Eastern North America (Eastern United States and Southern Ontario)
Growing Season
Leafs out late in spring, flowers in May-June, fruits (nuts) ripen in September-October, enters dormancy early in fall with yellow foliage.
Sunlight & Water Needs
Full sun; requires well-drained, deep, fertile, moist soils for best growth; moderate drought tolerance once established.
Mature Size
70 to 100 feet in height with a similar spread of 70 to 100 feet; can live over 150 years.
Special Characteristics
Produces juglone (an allelopathic chemical that hurts nearby plants), highly valuable timber for furniture, edible nuts, and vibrant yellow fall color.
Wildlife & Ecology
Provides food (nuts) for squirrels, woodpeckers, and foxes; serves as a host plant for the Luna Moth; provides nesting habitat for various forest birds.