White Walnut Juglans cinerea

Butternut is small to a medium-sized shade tree in the Juglandaceae or walnut family that usually lives for 75 years. It grows to a height of 40 to 60 feet and is equally as wide. It has an open, rounded, spreading crown. The trunk is short, forked, or crooked, and the branches are stout. The leaves are dark green, pinnately-compound measuring 10-20 inches long, and have 11 to 19 leaflets. The leaflets are 2 to 5 inches long and oblong to lanceolate. The edible fruits are tan and oval. The nut's shells can be hard to crack, but the nuts are sweet and oily and prized by humans and wildlife. 

Butternut is native to Eastern Canada and the Central and Eastern United States. This tree is usually found in moist bottomlands, lowland forests, swamps, river banks, and some drier limestone soils. It has been ravaged by the butternut canker, and native stands have been destroyed. The tree has been placed on the endangered species list in some parts of the United States and has been all but eliminated in some southern states, 

The genus name, Juglans, is derived from two Latin words. Jovis means Jupiter, and glans means an acorn or nut. The specific epithet, cinerea, is translated as gray and refers to the bark of the tree.

 Plant this tree in moist, well-drained soil in the full sun. It grows best along streambanks, on slopes, and on rock ledges. It does not tolerate shade or competition.  Established trees tolerate drought and browsing by rabbits. As with black walnut, butternuts produce juglones which are toxic to other plants. The effect usually extends out to the drip line.

Butternut and the Black Walnut trees resemble each other. The may difference is the Black Walnut's fruits will stain your hands, and the stem and crushed leaves have a strong odor. 

Some recommend that it is best not to plant the Butternut because of its susceptibility to butternut canker. It is generally not used as an ornamental tree, but it is planted for its fruits.

Seasons Of Interest:

Bark:  Winter   Bloom: Spring to Early Summer      Foliage:  Spring, Summer, and Fall     Fruits:  Fall

Quick ID Hints:

• deciduous, medium to large tree, with open, rounded, spreading crown, growing up to 40 to 60 feet tall
• the trunk is short, forked, or crooked
• chambered pith
• leaves alternate, crowded at tips, pinnately compound with 11 to 17 leaflets, leaflets oblong to lanceolate, terminal leaflet present
• dense pad of hairs above the leaf scar
• male flowers are yellowish-green catkins, and female flowers are short spikes--bloom from April to June
• fruit is a sweet nut with a hard shell that is encased in a greenish outer husk with 2 to 4 longitudinal ridges
• older bark gray to grayish-brown with scattered lenticels, develops narrow, flat ridges and shallow furrows

Insects, Diseases, and Other Plant Problems:  The tree is endangered in its native range due to butternut canker disease and overharvesting. The canker has devastated the tree and there is no cure. It may also suffer from blight. Potential insects include wood borers, nut weevils, lace bugs, husk flies, bark beetles, and butternut curculio. The common grackle has been known to destroy immature fruit, and they are classified as pests. This tree is also susceptible to fire and storm damage.

The roots of the Butternut release a chemical known as juglone. This chemical can stunt the growth or kill plants such as azaleas, rhododendrons, lilacs, peonies, tomatoes, potatoes, peppers, and eggplants. The toxic zone extends 60 to 80 feet from the trunk of the tree. The husks of the Butternut also secrete a strong dye that stains clothing and skin.

VIDEO created by Grant L. Thompson for “Trees, Shrubs, and Woody Vines for Landscaping” a plant identification course offered by the Department of Horticulture at Iowa State University.