It’s a plant introduced in almost all temperate regions in cultivated areas.
The common walnut is the origin of cultivated varieties which produce the edible walnut, consumed around the world.
Juglans regia is a large deciduous tree, attaining heights of 25–35 m, commonly with a short trunk and broad crown, though taller and narrower in dense forest competition. It is a light-demanding species, requiring full sun to grow well.
The bark is smooth, olive-brown when young and silvery-grey on older branches, and features scattered broad fissures with a rougher texture. Like all walnuts, the pith of the twigs contains air spaces; this chambered pith is brownish in color. The leaves are alternately arranged, 25–40 cm long, odd-pinnate with 5–9 leaflets, paired alternately with one terminal leaflet. The largest leaflets are the three at the apex, 10–18 cm long and 6–8 cm broad. The male flowers are in drooping catkins 5–10 cm long, and the female flowers are terminal, in clusters of two to five, ripening in the autumn into a fruit with a green, semifleshy husk and a brown, corrugated nut. The whole fruit, including the husk, falls in autumn; the seed is large, with a relatively thin shell, and edible, with a rich flavour.
It’s widely grown for different uses, especially the wood and the fruits. The used parts are leaves, husks and buds.
It’s rich of tannin, flavonoid, gallic acid, caffeic and ascorbic acid.
From September to November
walnut wood can be used for flooring, solid wood or veneer for musical instruments and furniture, and interior decoration.
The fruit, the nut is eaten as a food as dry fruit, or to extract the walnut oil for food use and as oil paint.
Walnut husk still soft in their green can be use also for Nocino liqueur.
create a brown dye
The dry husk is used for dyeing to create brown tone color for textile and especially as natural hair dye.