Skip to content

Juglans nigra

Black walnut thrives in full sun. That’s why you’ll often find it at the edges of roads, forests, and clearings.


Today, the arboretum hosts over a dozen black walnut trees. Look out from them as you wander from the corner of May and Lovell towards the Lovell Street entrance, and then again as you’re by the Magnolia Trail.

Black walnut leaf

History at Hadwen

The black walnut has been documented in the aboretum since at least 1900, when Hadwen wrote there was a black walnut “from Japan producing fruit in clusters” on his property. He felt that the walnut “makes a fine vigorous tree; tall, with spreading habit; its leaves long, swaying gracefully in the breeze.”

Keep Learning

Detailed Species Information

Black walnut is a deciduous walnut tree in the family Juglandaceae. Black walnut is widely distributed across the eastern United States, typically found in riparian areas. These trees can grow quite large, with the largest known living black walnut in the United States standing 112 feet (34 meters) tall and 8 ft (2.6 meters) in diameter. This tree is characterized by a pungent smell throughout most parts of the plant except the nuts. Typically, the tree has dark gray bark with deep furrows that appear in diamond shapes. Black walnut has pinnately compound leaves that are alternately arranged on the stem and are a dark green color.

Black walnut is a “pioneer species” and intolerant to shady conditions. Because of this, black walnut can be typically found by the edges of roads, forests, and fields. This has allowed black walnuts to become increasingly common following a series of epidemics that have killed off large numbers of other tree species such as elm, ash, and hemlock. Since the range of black walnut overlaps with the Texas black walnut (J. microcarpa), the two species have been known to crossbreed. Commercially, this tree is important for its deep-colored, easy-to-work wood and its nuts, which are said to have a unique flavor. Black walnut is also a common ornamental tree in many parks and gardens and has been used for reforestation and weed control.

Contact Information

Hadwen Arboretum