The Black Walnut Leaf is a compound leaf typically found on the Black Walnut tree (Juglans nigra). Each leaf is composed of 15-23 leaflets arranged alternately along a central stem, with each leaflet being lance-shaped and having a serrated edge.
 
The leaves are dark green and emit a distinctive aroma when crushed. They are known for their allelopathic properties, which can inhibit the growth of surrounding plants.