Black Walnut
Juglans nigra · Deciduous Broadleaf
Plant Family
Juglandaceae
Tree Category
Forest Tree, Nut Tree, Timber Tree
Variety / Cultivar
None (Wild type)
Hardiness Zones
USDA Zones 4-9; adaptable to various climates but thrives in rich alluvial soils.
About This Tree
A large, majestic hardwood with a deep taproot and a high, spreading crown. Known for its prized dark heartwood and large edible nuts. Often seen in forests or as legacy pasture trees.
Leaf Characteristics
Pinnately compound, 12-24 inches long with 15-23 leaflets; leaflets are ovate-lanceolate with finely serrated margins; medium green turning yellow in fall.
Bark Characteristics
Dark brown to grayish-black with deep, diamond-shaped furrows and thick, interlacing ridges; inner bark is light brown.
Growing Information
Origin Region
Eastern North America, adapted to fertile river bottoms and moist hillsides.
Growing Season
Late leafing in spring, early dormancy in fall; flowers in spring (late May) with fruits ripening in autumn.
Sunlight & Water Needs
Full sun (highly shade-intolerant); requires moist, well-drained, fertile soil; moderate drought tolerance once established.
Mature Size
70-100 feet in height, 60-80 feet spread; moderate growth rate; can live up to 250 years.
Special Characteristics
Produces juglone (an allelopathic chemical that inhibits growth of nearby plants); highly valuable for premium furniture and veneer; nuts have a rich, distinct flavor.
Wildlife & Ecology
Provides essential high-protein food for squirrels and other rodents; leaves are larval hosts for Luna moths; provides nesting sites for large birds.