Wednesday, May 6, 2020
Butternut - Juglans cinerea
The Butternut - Juglans cinerea, is a medium to large sized deciduous tree that can reach heights upwards of 75 feet in ideal growth conditions. It is sometimes also referred to as the White Walnut and is best recognized because of it's combination of long pinnate leaves with multiple leaflets and sticky 4-angled fruit husk. It is native to the woodlands, floodplains, river terraces, and rocky slopes of the Eastern United States. Found from New Brunswick, West through Minnesota in the North continuing South to South Carolina, Georgia, Northern Alabama, Northern Mississippi and Arkansas. It is sometimes confused with the Black Walnut (Juglans nigra) but the fruit husks are greatly different as one has ridges and the other lacks ridges and angles all together. This species is considered to be at risk as the Butternut Canker a fungal disease caused by Sirococcus clavigignenti-juglans-dacearun, has wiped out large populations throughout the native growth range.
Image Citation: Bill Cook, Michigan State University, Bugwood.org
The bark of the Butternut is a light grey or brown, thick and deeply furrowed. The Leaves are alternate and pinnately compound with 11-17 leaflets one of which is a terminal leaflet. Each leaflet is 5-11 cm long and about 6 cm wide, narrow and ovate in shape with a tapering point at the end. The upper portions of each leaflet is a yellow green color while the lower is a paler in color, hairy and often sticky to the touch. In the fall the color of the leaves changes to a bright yellow or yellow-brown. The edible fruit is a brown ellipsoid or ovid drupe (nut) that is 5-8 cm long with a thick husk, it is sticky to the touch and mostly 4 sided. The kernel of the fruit is oily and matures in late Summer or Early Fall. The male flower of the Butternut are cylindrical, hairy and a green-yellow and occur as catkins that are 6-14 cm long, the female flowers occur as spikes of 4-7 flowers at the branch tips. The sweet sap of the Butternut is also edible and can be tapped during the Spring season. Butternut sap can be used as a refreshing drink, or boiled down to a syrup or sugar. The wood of the Butternut is coarse grained, soft, and very attractive, it weighs about 25 lb per cubic foot and is not as valuable a crop as the Black Walnut (J. nigra), but can also be used indoors for furniture, doors or trim.
Image Citation (Male Flowers): Steven Katovich, USDA Forest Service, Bugwood.org
Image Citation (Female Flowers):Steven Katovich, USDA Forest Service, Bugwood.org
The Butternut is recommend for hardiness zones and would make a lovely shade tree and nut producer in your landscape. Butternuts are the easiest of the native tree nuts to harvest and process though they are messy so be prepared for that when and if you decide to plant one in your yard. They are truly remarkable, in the sense that the nuts can remain fresh and edible for more than 25 years if the un cracked nuts are kept dry. Take care when trying to harvest the fruits/nuts as Butternut and Walnut husks emit a dye that will turn your skin and clothes brown. All trees in the Juglans family (this includes Butternut and Walnuts) generate a chemical from their root systems that will seep into the surrounding soil, the toxin, called juglone, prevents the growth of some species of plants. The most notable plants that can not tolerate juglone in their surrounding soils are rhododendrons, azaleas and crops such as potatoes and tomatoes.
Image Citation (Single Nut): Bill Cook, Michigan State University, Bugwood.org
Butternut products have been used for generations for medicinal purposes. The Native Americans used the Butternut as a laxative and/or tonic to remedy arthritic or rheumatic conditions, headaches, dysentery, constipation and treat wounds. Modern medicine still recognizes Butternut as a remedy for chronic constipation as it helps gently produce bowel movements. The inner bark is one of the few laxatives that are considered safe for use during pregnancy. Butternut products have also been found to lower cholesterol and promote healthy liver function by improving the clearance of waste from the organ.
Image Citation (Butternut): Paul Wray, Iowa State University, Bugwood.org