A genus of unarmed trees and shrubs widely spread over E. Asia, and extending to Australia and Madagascar. Of about fifty species, the only hardy species in cultivation are a few deciduous ones which were introduced from China by Wilson, and one from Korea. They are small trees of the same type as Phellodendron, sometimes aromatic. Young shoots very pithy, marked with lenticels, axillary buds exposed. Leaves opposite, pinnate. Flowers borne in broad flattish corymbs terminating the shoots of the year, often unisexual, small; sepals, petals, and stamens four or five in number. Fruit a capsule of four or five carpels which split from the top, revealing shining black seeds the size of gun-shot.
Among cultivated trees these euodias most closely resemble ‘Phellodendron, but they are very readily distinguished from that genus by the buds in the leaf-axils being exposed. (In Phellodendron the buds are quite hidden in the base of the leaf-stalk.)
The Forsters, father and son, who founded this genus in 1776, spelt the name ‘Euodia’, but convention once demanded that the Greek prefix ‘eu-‘, when occurring before a vowel, should be written ‘ev-’ – hence ‘Evodia’, the established spelling. This rendering is, however, contrary to present-day rules of nomenclature and the original spelling can therefore be restored (cf. ‘Euonymus’, once commonly spelt ‘Evonymus’).