BARBERRY (Berberis vulgaris), a spiny shrub of the bar berry family (Berberidaceae), native to Europe and Asia and naturalized in Great Britain and the eastern United States. It bears spiny-toothed leaves, bright yellow flowers, and scarlet berries, sometimes used for preserving. The shrub has long been grown as an ornamental, but, because it serves as a host plant for the destructive wheat rust, its culture in some districts is prohibited. The American barberry (B. canadensis) is native to the Allegheny mountains. (See BERBERINE; MAHONIA.)