THE WALNUT FAMILY (Juglandaceae)

This is a family of trees mainly native to the Americas, Eurasia and Southeast Asia. The plants are aromatic, rich in tannin, leaves, flowers and fruit often possessing scaly or hairy resinous glands. They include the commercially important nut and timber producing trees, walnut (Juglans), pecan (Carya illinoiensis) and hickory (Carya sp.) The Persian walnut (Juglans regia) is one of the major nut crops in the world. It has been introduced into Central Europe and is now widely spread.

Juglandaceae have large, aromatic leaves, usually alternate and pinnately compound or trifoliate. Flowers are wind pollinated often male and female carried separately though on the same plant. The petals are reduced or absent and flowers individually small and insignificant. Male flowers usually numerous and arranged in catkins, female clusters typically smaller. The fruit is usually in the form of a nut enclosed in a fibrous case that breaks open when the seed matures. (This description represents a simplification and concentrates on the characteristics most useful for the understanding of familiar locally occuring species)

(source: Wikipedia)