Black Walnut
Juglans nigra · Deciduous Broadleaf Hardwood
Plant Family
Juglandaceae
Tree Category
Nut Tree, Shade Tree, Timber Tree
Variety / Cultivar
None (Wild type)
Hardiness Zones
USDA Zones 4-9; highly adaptable to various temperate climates within these zones.
About This Tree
A large, stately forest tree with a broad, open crown. Known for its high-quality dark wood and edible nuts. It exhibits a straight trunk and a rounded canopy at maturity, often spreading as wide as it is tall.
Leaf Characteristics
Pinnately compound, 12-24 inches long, consisting of 15-23 ovate-lanceolate leaflets. Leaflets are medium green with finely serrated margins, turning yellow in autumn. Terminal leaflet is often missing or small.
Bark Characteristics
Dark gray to grayish-brown or black; deeply furrowed into thin, diamond-shaped ridges that form a rough, scaly pattern with age. Inner bark is dark brown.
Growing Information
Origin Region
Native to Eastern North America, spanning from Southern Ontario to Florida and west to the Great Plains.
Growing Season
Leaves emerge in late spring (one of the last trees to leaf out); flowers in April or May; nuts ripen in autumn; enters dormancy early after first frost.
Sunlight & Water Needs
Full sun is required; it is shade-intolerant. Prefers deep, moist, well-drained, fertile loamy soils but has moderate drought tolerance once established.
Mature Size
70-100 feet in height with a similar spread; growth rate is moderate; can live for 150 to 200 years.
Special Characteristics
Produces juglone, an allelopathic chemical that inhibits the growth of many other plants; exceptionally high timber value for furniture; nuts are hard-shelled but prized for their bold flavor.
Wildlife & Ecology
Provides critical food for squirrels and other rodents; attracts several species of butterflies and moths as a host plant; provides nesting sites for large birds.