A majestic tree growing up to 40 m tall with dark brown rough bark.  It is common throughout the eastern and central United States and is fairly abundant in our state. It has alternate compound leaves with 15-23 leaflets. In the autumn, the leaves turn from green to yellow. The leaflets tend to fall to the ground separately and full intact leaves are rare on the ground. In October the tree produces a large brownish-green semi-fleshy aromatic husk containing a brown, corrugated nut. The internal seed is small and very hard. The trees seem to produce fruit more heavily in alternate years. 

Walking under a stand of black walnut trees can be a bit of a hazard. The heavy fruit fall randomly and could make a significant bump on the head. It is also difficult to walk over the fallen fruit and a turned ankle is a possibility for those who do not take care. The leaves and fruit seem to fall at about the same time. The seed can be eaten, but is difficult to extract by hand. The green outer casing tends to rot quickly on the ground and the hard shell is difficult to break open. The juices will also stain human skin. It is grown commercially, but the imported Persian walnut is more commonly sold in stores.