Juglans nigra, or black walnut, also known as American walnut, is native to eastern North America, specifically from southern Ontario, Canada, south to Texas and Florida, and west to Minnesota and South Dakota. While it produces juglone, a chemical toxic to some plants, most tree species do not have an issue being planted with it. Black walnuts thrive in full sun with well-drained, organically rich soils, and are tolerant of both acidic and alkaline soils, as well as salt spray. Its yellow-green fruit feeds wildlife and supports the banded hairstreak butterfly. Though it is messy due to its fallen leaves and hard-shelled nuts, pruning is best done in the dormant season. While slow to produce nuts, black walnuts can yield significant crops after 20 years.