Black Walnut
Juglans nigra · Deciduous Broadleaf Hardwood
Plant Family
Juglandaceae
Tree Category
Nut Tree, Timber Tree, Shade Tree
Variety / Cultivar
Wild type / Standard species
Hardiness Zones
USDA Hardiness Zones 4 through 9
About This Tree
Large, majestic deciduous tree with a tall straight trunk and broad, open crown. Known for its dark, deeply furrowed bark visible on cut logs and fresh woodchips, and highly valuable dark chocolate-brown heartwood.
Leaf Characteristics
Alternate, pinnately compound leaves 12-24 inches long with 15-23 ovate-lanceolate finely serrated leaflets. Bright yellow fall color before early drop.
Bark Characteristics
Dark grey-brown to black, deeply furrowed with prominent diamond-shaped ridges. Inner bark reveals dark chocolate-brown tones when cut.
Growing Information
Origin Region
Eastern North America, widely naturalized in temperate regions
Growing Season
Leafs out late in spring (May), flowers in May-June, fruits mature in autumn (September-October), enters dormancy early in autumn
Sunlight & Water Needs
Requires full sun. Prefers moist, well-drained, rich alluvial soils; moderately drought tolerant once deeply rooted.
Mature Size
70 to 100+ feet tall, 60 to 80 feet spread, fast growth rate when young, can live up to 150-250 years, trunk diameter 2-4 feet.
Special Characteristics
Produces juglone (allelopathic chemical inhibiting sensitive companion plants), high timber value for fine woodworking and cabinetry, edible nuts, natural dye source from husks.
Wildlife & Ecology
Nuts are a primary food source for squirrels, mice, and large birds. Host plant for Luna moth caterpillars and several species of butterflies and moths.