The black walnut (Juglans nigra) is a deciduous native of the United States and is among the most widely distributed of all the North American trees. The tree's lumber is also considered among the most valuable North American hardwoods. The black walnut tree has specific growth traits and has a long life.
The black walnut tree is a long-lived tree, often growing well beyond 200 years. It is not uncommon to see black walnut trees with trunk diameters of up to 4 feet. Though the tree is distributed throughout the country, its natural range is in the Eastern and Central regions of the United States.
The large-sized black walnut tree grows to anywhere between 70 and 100 feet tall with a crown spread of up to 70 feet. The tree has a shorter trunk in its native habitat. The 1- to 2-foot-long compound foliage is aromatic. The leaves have yellowish green uppersides with lighter, fuzzy undersides. The nuts of the tree are 2 to 3 inches in diameter and have a green, warty covering, ripening and falling from the tree in October. The bony familiar nut is contained inside the husk.
Grow the tree in a deep, fertile, moist and well-drained ground. The recommended depth of the soil is at least 30 inches before it hits gravel or bedrock. Preferable soil texture is loam, silt loam, sandy loam or silty clay loam. Black walnut does not thrive in rocky, dry, sandy or poorly drained ground. The tree is hardy in U.S. Department of Agriculture zones 3 through 9 and is intolerant of shade.
The nuts of black walnuts are rich in oils and are used in commercial baking, as fresh nuts and in the candy industry. The tree itself is used as a hardy shade tree in larger landscapes. The top-quality wood veneer is used for covering doors, wall panels, cabinets and furniture. Lumber is used for making high-quality furniture. Tree areas not used in lumber are cut and used in the production of novelty items.