Black Walnut
Juglans nigra · Deciduous hardwood
Plant Family
Juglandaceae
Tree Category
Shade and Nut Tree
Variety / Cultivar
Species type (wild type Juglans nigra)
Hardiness Zones
Thrives in USDA Hardiness Zones 4 through 9.
About This Tree
A large, imposing deciduous tree with a straight trunk, rounded open crown, and compound leaves. Known for its valuable dark wood, edible nuts, and allelopathic chemical juglone.
Leaf Characteristics
Pinnately compound leaves, typically 12 to 24 inches long, featuring 15 to 23 leaflets. Leaflets are ovate-lanceolate, finely serrated, and show some brownish spotting from fungal leaf spot in the image.
Bark Characteristics
Dark brown to nearly black, deeply furrowed with rounded ridges forming a diamond-shaped pattern that becomes rough and rigid as the tree ages.
Growing Information
Origin Region
Native to eastern and central North America, well-adapted to rich, deep bottomlands and moist, fertile soils.
Growing Season
Leafs out in late spring, producing small catkins in spring followed by nuts that ripen in autumn. Enters dormancy in late fall after dropping yellow foliage.
Sunlight & Water Needs
Requires full sun for optimal growth. Prefers moist, well-draining soils but exhibits moderate drought tolerance once established.
Mature Size
Reaches a height of 50 to 75 feet with an equal or greater spread, growing at a moderate rate with a lifespan exceeding 130 years.
Special Characteristics
Produces allelopathic juglone which inhibits the growth of certain plants underneath its canopy. Highly prized for dark, rich timber and edible nuts.
Wildlife & Ecology
Supports numerous mammal species including squirrels which consume and cache the nuts. Provides nesting sites and perches for various birds.