A genus of herbs in which the leaves are large and palmately lobed. The inflorescence is an erect panicle; the flowers are small and entomophilous. Rhubarb is the petiole of R. rhaponticum, and medicinal rhubarb (a purge) is R. officinale. There are about 50 species, occurring in temperate and subtropical Asia.
Subjects: Plant Sciences and Forestry.