bean gall A red or pink, kidney-bean-shaped gall, found on the leaves of Salix species (willow) and caused by the small sawfly, Pontania proxima (family, Tenthredinidae). A second brood laid in the early autumn by the adults that emerged in summer may over-winter in the gall. Sometimes the term ‘bean gall’ is used more generally to describe any red or brown gall caused by any Pontania species. Many galls may occur on a single leaf and, like other gall-causing species, the insects support a large community of parasites and hyperparasites.

bean gall A red or pink, kidney-bean-shaped gall, found on the leaves of Salix species (willow) and caused by the small sawfly Pontania proxima (family Tenthredinidae). A second brood laid in the early autumn by the adults that emerged in summer may overwinter in the gall. Sometimes the term ‘bean gall’ is used more generally to describe any red or brown gall caused by any Pontania species. Many galls may occur on a single leaf and, like other gall-causing species, the insects support a large community of parasites and hyperparasites.