Juglans cineraria, butternut

Juglans cineraria-Butternut

Family: N.O. Juglandaceae

Other names: White Walnut, Oilnut, Wallia cinerea, Nux cinerea

hazardsmallThe naphthoquinone constituents may cause gastric (stomach) irritation. Avoid in patients with gallstones.


Habitat: North America. Butternut grows best on stream banks and on well-drained soils. It is seldom found on dry, compact, or infertile soils. It grows better than black walnut, however, on dry, rocky soils, especially those of limestone origin.

Butternut is found most frequently in coves, on stream benches and terraces, on slopes, in the talus of rock ledges, and on other sites with good drainage. It is found up to an elevation of 1500 m (4,900 ft) in the Virginias – much higher altitudes than black walnut.

By Modal Jig (Own work) [CC-BY-SA-3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

A butternut tree bearing fruit

Description of Butternut:

Juglans cinerariaButternut, is a deciduous tree growing to 20 m tall, rarely 30 m, and 40–80 cm stem diameter, with light gray bark. The leaves are pinnate, 40–70 cm long, with 11–17 leaflets, each leaflet 5–10 cm long and 3–5 cm broad. The whole leaf is downy-pubescent, and a somewhat brighter, yellower green than many other tree leaves. The male flowers are inconspicuous yellow-green catkins produced in spring at the same time as the new leaves appear, and the female flowers have light pink stigma. The fruit is a nut, produced in bunches of 2–6 together; the nut is oblong-ovoid, 3–6 cm long and 2–4 cm broad, surrounded by a green husk before maturity in mid autumn. Butternut grows quickly, but is rather short-lived for a tree, rarely living longer than 75 years.

Key characteristics:

  • Alternate, compound leaves
  • Odd number of leaflets – has a terminal leaflet
  • Fruit normally grows in groups of 2–3 and is lemon-shaped

Cultivation of Butternut:

Requires a deep well-drained loam and a position sheltered from strong winds . Prefers a slightly alkaline soil . Prefers a sandy soil with a pH around 6 to 7 . Dislikes compacted soils or clay sub-soils, otherwise trees grow well on most soils . This is the most cold-resistant of the walnuts , tolerating temperatures down to about -35°c in N. America when fully dormant . It is less hardy in Britain, unfortunately, because the wood does not ripen so well here due to our cooler summers. The young growth in spring can be damaged by late frosts . Sometimes cultivated in N. America for its edible seed, there are some named varieties . Trees can come into bearing in 6 – 10 years from seed and fruiting is usually biennial . The trees are quite short-lived, seldom exceeding 80 – 90 years . They require about 105 frost-free days in order to ripen a crop in N. America . Unfortunately, they have not proved successful as a nut tree in Britain, usually failing to produce a crop. This is probably due to our cooler summers . It is sometimes planted as a timber tree in Denmark and Rumania . Plants produce a deep taproot and are intolerant of root disturbance. Seedlings should be planted out into their permanent positions as soon as possible and given some protection for their first few winters since they are somewhat tender when young . Trees cast a dense shade which reduces the amount of species able to grow below them . We have no specific information for this species, but the roots of several members of this genus produce substances that are toxic to many plant species, especially apples (Malus species), members of the Ericaceae, Potentilla spp and the white pines (certain Pinus spp.) . The leaves of many species also secrete substances that have an inhibitory affect on plants growing underneath them. All in all this is not a very good companion plant . Plants should only be pruned when they are fully dormant in winter or when they are in full leaf, otherwise any cuts will bleed profusely . Hybridizes with J. ailantifolia, there are some named varieties of this hybrid that are grown for their edible seed .

Propagation of Butternut:

The seed is best sown as soon as it is ripe in individual deep pots in a cold frame . You need to protect it from mice, birds, squirrels etc. The seed usually germinates in late winter or the spring. Plant out the seedlings into their permanent positions in early summer and give some protection from the cold for their first winter or two. The seed can also be stored in cool moist conditions (such s the salad compartment of a fridge) over the winter and sown in early spring but it may then require a period of cold stratification before it will germinate .

Culinary uses of Butternut:

Edible Parts: Oil;  Sap;  Seed.
Edible Uses: Oil;  Sweetener.

Seed – eaten raw or ground into a powder and used with cereal flours in making cakes, biscuits, muffins, bread etc . Oily and sweet tasting with a rich agreeable flavour . The oil in the seed is not very stable and the seed soon becomes rancid once it is opened . The kernel is usually only about 20% by weight of the whole seed and is hard to extract . The unripe fruit can be pickled . The seed is 3 – 6cm in diameter and is produced in clusters of 3 – 5 fruits . An edible oil is obtained from the seed , it tends to go rancid quickly. The sweet sap is tapped in spring and can be used as a refreshing drink . It can also be boiled down to a syrup or sugar, or added to maple syrup .

Juglans_cinerea_botanicalMedicinal uses of Butternut:

Actions: Laxative, Cholagogue, antihelmintic.

Part Used: Inner bark.


Butternut is used as a dermatological agent, antihaemorrhoidal and cholagogue. It is a purgative. Ellingwood says: “Experiments with the drug have ascertained that it influences, with great energy, the liver, small intestines, colon and rectum, causing and increased manufacture and elimination of bile, as well as increased activity of the glands of the intestinal tract. Full doses produce large bilious evacuations, without much pain or griping, in which respect its action very much resembles that of Iris versicolor.” He suggests its use in: Chronic jaundice, constipation, skin diseases, eczema, herpes, acne, impetigo pemphigus.

Preparations & Dosage of Butternut:

Tincture: 1-2ml.


Juglans is a mild but pretty active cathartic, producing but little if any pain, and not debilitating the bowels. In this respect it resembles rhubarb. In combination with podophyllum or podophyllin it is very valuable in remittent and intermittent fevers, particularly in those cases attended with hepatic torpor and visceral congestion.

Other uses of Butternut:

Wood, Dye, Oil, Herbicide

Butternut wood is light in weight and takes polish well, is highly rot resistant, but is much softer than black walnut wood. Oiled, the grain of the wood usually shows much light. It is often used to make furniture, and is a favorite of woodcarvers. Wood – coarse-grained, light, soft, not strong, very attractive. It weighs 25lb per cubic foot.

Butternut bark and nut rinds were once often used to dye cloth to colors between light yellow and dark brown. To produce the darker colors, the bark is boiled to concentrate the color. This appears to never have been used as a commercial dye, but rather was used to color homespun cloth. As a dye it does not require a mordant. A black dye is obtained from the young roots.

Plants produce chemicals which can inhibit the growth of other plants. These chemicals are dissolved out of the leaves when it rains and are washed down to the ground below, reducing the growth of plants under the tree. The roots of this species produce substances that are toxic to many plant species, especially apples (Malus species), members of the Ericaceae, Potentilla spp and the white pines (certain Pinus spp.).

Esoteric uses of Butternut:

None known but if you use it please let us know!

The Chemistry:
  • Naphthaquinones, including juglone, juglandin and juglandic acid.
  • Fixed and essential oil.
  • Tannins.

 Please do not mistake this with Butternut Squash! Butternuts come from trees not growing on the ground like squashes.