Rhubarb, like sorrel and buckwheat, belongs to the Polygonaceae family of knotweeds. The well-known vegetable species, Rheum rhabarbarum, the stalks of which are used to make compotes, pies, and jams, is distinct from “Chinese rhubarb” (or “ornamental rhubarb”), Rheum palmatum. The latter is recognizable by its stalk, which grows up to 3 m in height, branches off at the inflorescences, and is surrounded by abundant clusters of flowers. Pharmaceutical use was made only of the roots [8. 841–…