Juglans

views updated

Juglans (walnut; family Juglandaceae) A genus of deciduous, nut-bearing trees, up to 30 m tall, that have twisting, spreading branches. They have large, oily, deeply lobed cotyledons. The leaves are compound. Male and female catkins occur on the same tree, the male catkins dangling in the wind, the female catkins upright. They produce oval, green fruits (a drupe) with a fleshy exocarp and a bony endocarp (the shell, see PERICARP), which splits down the midrib. The wrinkled, woody nut is eaten fresh or pickled, and used in desserts, cakes, and confectionery. The most popular garden species are J. regia (Persian walnut), J. nigra (black walnut), and J. cinerea of N. America, the butter-nut. The wood is used for furniture. There are 21 species, occurring mainly in northern temperate regions, but extending to the tropics and native to Asia and America.

walnut

views updated

wal·nut / ˈwôlˌnət/ • n. 1. the large wrinkled edible seed of a deciduous tree, consisting of two halves contained within a hard shell that is enclosed in a green fruit. 2. (also walnut tree) the tall tree (genus Juglans, family Juglandaceae) that produces this nut, with compound leaves and valuable ornamental timber. Its several species include the common (or English) walnut (J. regia) and the black walnut (J. nigra).

walnuts

views updated

walnuts The rough‐shelled English walnut (so called because for centuries English ships carried it world‐wide), black walnut, hickory nut, and butternut are all botanically walnuts. Common English walnut is Juglans regia. A 60‐g portion (nine nuts), is a rich source of vitamin E, copper, and selenium; a good source of protein, niacin, iron, and vitamin B1; a source of calcium and zinc; contains 40 g of fat, of which 10% is saturated and 75% mono‐unsaturated; provides 3 g of dietary fibre; supplies 400 kcal (1670 kJ).

walnut

views updated

walnut Deciduous tree native to North and South America, Europe and Asia. It has smoother bark than hickory, to which it is related, and is grown for timber, ornament, and nuts. Height: to 50m (165ft). Family Juglandaceae; genus Juglans.

walnut

views updated

walnut walnuts and pears you plant for your heirs proverbial saying, mid 17th century; meaning that both trees are traditionally slow growing, so that the benefit will be felt by future generations.

See also a woman, a dog, and a walnut tree.

walnut

views updated

walnut Late OE. walh-hnutu (once), corr. to MLG. wallnut, MDu. walnote (Du. walnoot), ON. walhnot; Gmc. formation on *walχaz foreign and *χnut- NUT.

walnut

views updated

walnut See JUGLANS.