Any tree of the genus Fraxinus , in the olive family.
The genus includes about 70 species of trees and shrubs found mostly in the Northern Hemisphere. The U.S. boasts 18 species of ash, 5 of which furnish most of the ash cut as lumber. Most important are the white ash ( F. americana ) and the green ash ( F. pennsylvanica ), which yield wood that is stiff, strong, and resilient, yet lightweight. This "white ash" is used for baseball bats, hockey sticks, paddles and oars, tennis and other racket frames, and the handles of agricultural tools. Black ash ( F. nigra ), blue ash ( F. quadrangulata ), and Oregon ash ( F. latifolia ) produce wood of comparable quality that is used for many more purposes, including furniture, interior paneling, and barrels.