Black Walnut
Juglans nigra · Deciduous, Broadleaf, Hardwood
Plant Family
Juglandaceae
Tree Category
Shade Tree, Nut Tree, Forest Tree
Variety / Cultivar
None specified (Wild type)
Hardiness Zones
USDA Hardiness Zones 4-9; highly adaptable to various temperate climates within this range.
About This Tree
A large, stately forest tree with a straight trunk and an open, rounded crown. It features pinnately compound leaves and produce large, green-husked nuts. The tree is known for its high-quality timber and characteristic dark, furrowed bark.
Leaf Characteristics
Pinnately compound, 12-24 inches long with 15-23 leaflets; leaflets are ovate-lanceolate with serrated margins; medium green color turning bright yellow in autumn; aromatic when crushed.
Bark Characteristics
Dark brown to greyish-black; deeply furrowed into thin, diamond-shaped ridges; inner bark reveals a chocolate-brown color when cut.
Growing Information
Origin Region
Native to Eastern North America; widely adapted to deep, well-drained fertile soils.
Growing Season
Buds burst in late spring (one of the last trees to leaf out); flowers in May-June; fruits ripen in autumn; enters dormancy early after first frost.
Sunlight & Water Needs
Full sun (intolerant of shade); requires moderate moisture and prefers moist, fertile, loamy soils; moderate drought tolerance once established.
Mature Size
Mature height of 70-100 feet; spread of 60-80 feet; moderate growth rate; can live up to 250 years; trunk diameter can reach 2-4 feet.
Special Characteristics
Produces juglone (an allelopathic chemical); highly prized for dark, fine-grained timber; distinctively flavored edible nuts; yellow fall foliage; high timber value.
Wildlife & Ecology
Provides essential food for squirrels and other rodents; attracts various moths; provides nesting sites for large birds; juglone production inhibits the growth of certain competing plants within the drip line.