Black Walnut
Juglans nigra · Deciduous, Broadleaf, Hardwood
Plant Family
Juglandaceae
Tree Category
Nut Tree, Shade Tree, Timber Tree
Variety / Cultivar
Native species (non-cultivar documented here)
Hardiness Zones
USDA Zones 4-9; highly adapted to the temperate climate of the Mid-Atlantic and Piedmont regions like Culpeper, VA.
About This Tree
A large, stately forest tree with a straight trunk and an open, rounded crown. Known for its high-value dark wood and edible nuts. It has a moderate growth rate and develops a deep taproot, making it difficult to transplant once established.
Leaf Characteristics
Pinnately compound leaves, 12-24 inches long with 11-23 leaflets. Leaflets are ovate-lanceolate, finely serrated, and often the terminal leaflet is missing or poorly developed compared to hickories. Color is bright green, turning yellow in fall.
Bark Characteristics
Grey-brown to near black; deeply furrowed into thin, diamond-shaped ridges that form a rough, interlacing pattern. Inner bark is dark brown if scraped.
Growing Information
Origin Region
Central and Eastern United States (including Virginia), Southern Ontario
Growing Season
Leafs out late in spring (late April/May); flowers in spring with catkins; fruits ripen in autumn; enters dormancy early in mid-to-late fall.
Sunlight & Water Needs
Full sun is required for optimal growth; prefers moist, well-drained, fertile loamy soils but is moderately drought-tolerant once established.
Mature Size
Mature height of 70-100 feet with a spread of 60-80 feet; trunk diameter can reach 2-4 feet; lifespan can exceed 150 years.
Special Characteristics
Produces juglone (an allelopathic chemical) that inhibits the growth of certain nearby plants like tomatoes and azaleas. Highly prized for dark, fine-grained timber and edible nuts with a strong, distinctive flavor.
Wildlife & Ecology
Provides critical food for squirrels, woodpeckers, and foxes through its nuts. It is the larval host for the Luna Moth and several other Lepidoptera. Offers excellent nesting sites for large birds.
Notes
Culpeper, Va