Black Walnut
Juglans nigra · Deciduous hardwood
Plant Family
Juglandaceae
Tree Category
Nut and shade tree
Variety / Cultivar
Species type (wild-type Juglans nigra)
Hardiness Zones
Thrives in USDA Hardiness Zones 4 through 9, demonstrating wide climatic adaptability across eastern and midwestern North America.
About This Tree
A large, majestic deciduous tree with a straight trunk, an open, rounded to oval crown, and coarse branching. It features highly prized dark timber, edible nuts encased in a green husk, and an open canopy that allows sunlight to reach the ground.
Leaf Characteristics
Alternate, pinnately compound leaves typically 1 to 2 feet long, containing 15 to 23 leaflets. Leaflets are oval-lanceolate with serrate margins, tapering to a point, and turn a soft yellow in autumn.
Bark Characteristics
Dark brown to nearly black, deeply furrowed into distinct, rounded ridges that often form a diamond-patterned texture, highly characteristic of mature individuals.
Growing Information
Origin Region
Eastern and central North America, well-adapted to rich, deep soils of river valleys and moist uplands
Growing Season
Spring leaf-out occurs relatively late, flowers in spring, produces large nuts maturing in autumn, and drops leaves early to enter winter dormancy
Sunlight & Water Needs
Requires full sun for optimal growth and nut production. Prefers deep, moist, well-drained soils but has moderate drought tolerance once established.
Mature Size
Reaches heights of 70 to 100 feet with a similar spread. Growth rate is moderate to fast, and it can live for 130 years or more.
Special Characteristics
Produces juglone, a chemical compound in its roots, leaves, and husks that inhibits the growth of certain surrounding plants (allelopathy). Highly valued for its rich, dark heartwood used in furniture and gunstocks.
Wildlife & Ecology
Supports numerous species of mammals, particularly squirrels and other rodents that feed on and cache the protein-rich nuts. Provides nesting sites for various birds and serves as a larval host for several moth species.