Juglans nigra
Large eastern North American deciduous tree valued for dense timber and edible nuts, with deeply furrowed bark and pinnately compound leaves, that releases juglone from roots to inhibit nearby plants.
Common Names
Black Walnut, Eastern Black Walnut, American Walnut
Summary
Black Walnut (Juglans nigra) is a tall native deciduous tree of eastern North America, with a broad crown and dark, deeply furrowed bark forming a diamond-pattern, it features long, alternate, pinnately compound leaves with 15–23 leaflets that are aromatic when crushed and turn yellow in fall, nuts develop in green husks and ripen in autumn, and dark, fine-grained heartwood is highly valued for furniture and gunstocks, the tree releases juglone, a chemical in roots and other tissues that can inhibit nearby plants, typically growing in moist, well-drained soils along streams and displaying shade intolerance that favors open, wildlife-rich landscapes, cultivation favors full sun and moist, well-drained soils, tolerating a wide pH range from acidic to alkaline, it has a deep taproot, making bare-root transplanting difficult, propagation is possible from seed or grafting, with direct seeding or nursery-propagated stock, and nut production can begin after about 4–6 years, with major production by around 10 years, plantings of 3–5 trees promote cross-pollination and better yields, pests and diseases include thousand cankers disease and walnut caterpillar, while husks yield a dye and nuts provide edible kernels, making the tree valuable for timber, wildlife habitat, and multiple practical uses
Lifecycle
Perennial
Height
600-900 inches
Spread
600-900 inches
Hardiness Zones
Zones 4-9
Sunlight Requirements
Ideally Full Sun, tolerates Partial Shade
Soil Type
Deep, well-drained, moist loam or sandy loam soil, fertile/organic-rich, with a pH range of 5.0–8.0.
Soil Drainage
Well-drained soil
Soil pH
5.0-7.5
Bloom Color
Insignificant
Bloom Time
Spring
Foliage Color
Dark Green
Fall Foliage Color
Yellow
Leaf Lifecycle
Deciduous
Growth Rate
Juglans nigra has fast growth in youth, typically about 2–3 feet per year (0.6–0.9 m), slower with age to about 1–2 feet per year (0.3–0.6 m), and on the best sites can reach about 3–4 feet per year (0.9–1.2 m).
Seasons of Interest
Spring, Summer, Fall, and Winter
Propagation Methods
Seeds, Cuttings, Layering
Attracts Wildlife
Attracts birds, attracts butterflies, not described as attracting bees or hummingbirds
Taxonomy
- Taxonomic Rank
- Species
- Author
- L.
- Publication
- Sp. Pl. : 997 (1753)
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Angiosperms
- Order
- Fagales
- Family
- Juglandaceae
- Genus
- Juglans
Synonyms
Juglans rugosa Juglans pitteursii Juglans nigra f. nigra Wallia nigra Juglans nigra f. oblonga Juglans nigra unr. oblonga Juglans nigra f. laciniata