A genus, Fraxinus, of deciduous trees of the olive family Oleaceae, order Scrophulariales, which have opposite, pinnate leaflets, except in one species, F. anomala, which has only a single leaflet. There are about 65 species in the Northern Hemisphere. This tree occurs in America south to Mexico, in Asia south to Java, and in Europe.
The white ash (F. americana), of the eastern United States, has stalked leaflets, rusty-colored winter buds, and an erect trunk that is valuable for lumber. The wood is light, strong, but flexible, and is used for oars, baseball bats, furniture, motor vehicle parts, boxes, baskets, and crates. The black ash (F. nigra) grows in wet soils in the northeastern United States and Canada and has sessile leaflets and friable outer bark. The wood of black ash is used for the same purposes as that of white ash. The red ash (F. pennsylvanica), also of the eastern United States and adjacent Canada, has pubescent (hairy) twigs and leafstalks. The uses of the wood of this species are also similar to those of white ash. Some species of ash are ornamental trees, such as the flowering ash (F. ornus) with gray winter buds and white flowers, and the European ash (F. excelsior) with black buds and sessile leaflets. Forest and forestry Tree