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Black Walnut Trees

Black Walnut (Juglans nigra)

Identification

A large deciduous tree prized for its dark brown hardwood. Due to its economic value, the number of large individuals remaining in the landscape is extremely low. Black Walnut has long compound leaves that hold up to 23 leaflets arranged opposite each other and often lacking a leaflet at the apex. Bark is deeply ridged well out onto the branches. Fall color is bright yellow and leaf scars are heart shaped with 3 dots or “bundle scars” on each point. Fruits conspicuous green balls that are held from midsummer well into the fall exhibiting various stages of rot. Both fruits and leaves have a spicy citrus smell when crushed or scraped.

Examples:

branches with leaves hanging
Leaves of the Black Walnut.

NPS Photo/ W. Kaselow

thin branches

NPS Photo/ W. Kaselow

bark of a tree
Bark of the Black Walnut.

NPS Photo/ W. Kaselow

green leaves draped from branches with two green fruits.
Fruits and Leaves of the Black Walnut.

NPS Photo/ W. Kaselow

Boston National Historical Park, Boston Harbor Islands National Recreation Area

Last updated: November 3, 2022