Juglans nigra is one of North America's most imposing native trees, capable of reaching 50 to 90 feet with a trunk spanning 3 to 6 feet in diameter at maturity. It prefers the rich bottomlands and fertile coves of the central and eastern United States, growing best in moist, organically rich, well-drained soil in full sun, though it tolerates partial shade. The lower branches tend to drop away as the tree matures, beginning its broad spread around 20 feet off the ground and developing a wide, rounded crown that makes it one of the more recognizable silhouettes in the eastern landscape. In October the yellow-green husks develop around the brown to black nuts, staining skin and clothing deeply if handled without gloves; the dye the husks produce is potent and has been used for centuries.

The nuts are edible and valued, though the husk is formidable and nut production in quantity typically takes two decades to develop properly. The tree is monoecious, carrying both male catkins and female flower clusters on the same plant. It serves as a host for the hickory horndevil moth, the luna moth, and banded hairstreak butterflies, and squirrels depend on it heavily. Its timber is a scarce and beautiful hardwood, used in fine furniture and veneer. The taproot runs deep, making transplanting difficult, and the juglone produced by leaves, stems, and roots can suppress or kill sensitive plants including azaleas, peonies, and tomatoes within the dripline. Planted where it has room, it works well as a shade tree in meadow and woodland settings.