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Black walnut

Juglans nigra

Walnut Family (Juglandaceae)

Introduction: Black walnut is a common tree throughout Kentucky. At one time it was abundant, especially in mixed forests on fertile soils. Large trees over 100 feet tall were once common, but most of these have been cut to clear farm land or harvested for its valuable lumber.

Culture: Black walnut grows best in fertile, moist soils. However, it will tolerate drier sites. It produces a tap root that makes it difficult to transplant.

Botanical Information

Native habitat: Native along the entire east coast from Florida to New England. It grows as far west as Minnesota.
Growth habit: The tree produces an open, rounded crown.
Tree size: Common to see trees 60 feet tall, however, it can reach 150 feet tall.
Flower and fruit: Male flowers are catkins; female flowers lack petals and are formed in spikes. The fruit is a nut with a lemon-scented outer covering.
Leaf: Leaves are compound having approximately 16 leaflets with fine teeth along the margin.
Hardiness: Winter hardy to USDA Zone 4.

Additional information: Black walnut is a valuable timber tree. The wood is prized for cabinet and furniture. Demand for the lumber is high and does not meet demand. Solid walnut furniture is uncommon today, with most pieces being made of walnut veneer.

Nuts are flavorful, but not as commonly available as English walnuts. In the wild, nuts are an important wildlife food.

Black walnut is a favorite host for mistletoe. Mistletoe is a plant parasite that lives in the tops of trees and takes water and nourishment from its host tree.

The National champion trees is Oregon and is over 130 feet tall. The Kentucky champion tree is in Nelson County and is 80 feet tall.