What Is a Walnut Tree, Exactly? Juglans, also known as walnut, is a genus of roughly 20 species of deciduous trees that are indigenous to North and South America, southern Europe, Asia, and the West Indies.
Walnut trees have long compound leaves with five to twenty-three short-stalked leaflets. On the same tree, distinct catkins—petalless flower clusters—carry the male and female reproductive organs. The pith of the twigs typically has several chambers. The fruit is a drupe, not a genuine botanical nut, with the edible seed (often termed a nut) wrapped in a shell inside of a thick husk.
Both the English or Persian walnut (J. regia), a native of Iran, and the black walnut (Juglans nigra), which grows in eastern North America, are valuable wood trees that bear edible walnuts. Eastern North American butternuts (J. cinerea) also yield a nut-like edible seed.
For the purpose of producing nuts for sale, the English walnut is grown in some regions of North and South America. Only trees grown in healthy, well-drained soils with a medium-heavy texture yield walnuts of high grade. The terminal leaflet is the largest of the round-tipped leaflets, which have smooth borders. Native North American walnuts have leaflets with serrated borders that are biggest in the centre of the leaf.
Eastern Europe and parts of Asia were the original home of the walnut tree, but it has long since spread to southern and western Europe as well as North America. Variety is also grown in China and Japan. A hard, protective shell surrounds the walnut fruit, which has long been appreciated for its flavour. The husks were used for dyeing, and the nuts produced oil for burning and cooking as well. The tree’s wood turned out to be perfect for furniture, panelling, and gunstocks.
Content for this question contributed by Jason Kranack, resident of Pittsburgh, Allegheny County, Pennsylvania, USA