Rheum
Collier's New Encyclopedia (1921)
rhubarb; a genus of Polygonex. Calyx inferior, petaloid, sixpartite; stamens about nine; ovary superior; ovule one, erect; styles three, reflexed; stigma, peltate, entire; achenium three-angled, winged, with the withered calyx at the base. R. rhaponticum is the common, or garden rhubarb. It is used in the United States in the making of pies, and is often called pie plant. plant. R. officinale, or R. palmatum, is the officinal rhubarb. R. emodi, in the Punjab Himalaya, from 6,200 to 14,000 feet, with R. moorcroftianum and R. speciforme, are the chief sources of the Himalayan or Indian officinal rhubarb. It is less active than the common kind. The stalks of R. emodi are eaten by the Hindus. Other Indian species are R. webbianum, R. nobile, R. arboreum, which yields so much honey that the ground under the plants is wet with it, and R. cinabarinum, said to poison goats in Sikkim. R. undulatum grows in China and Siberia. The roots of R. ribes are used by the Arabs as an acidulous medicine, and its leaf-stalks in the preparation of sherbet. In pharmacy, three leading kinds of rhubarb are recognized: recognized: (1) The Turkey or Russian rhubarb, which is wild neither in the one country nor the other, but used to be brought from China via Turkey, and then from China via Russia; (2) the East Indian, and (3) the Batavian rhubarb. An extract, an infusion, a syrup, a tincture, and a wine of rhubarb, with a compound rhubarb pill, are used in pharmacy. In small doses ses rhubarb is stomachic and slighty astringent; in large doses, a purgative, but its action is followed by constipation.
What Has Changed in the Last Century
Collier's in 1921 treated rhubarb chiefly as a drug, listing an extract, infusion, syrup, tincture, wine and compound pill, and noting that large doses purge. That pharmacy has almost vanished from Western medicine: the anthraquinone laxatives in rhubarb root (emodin and its relatives) fell out of favour as stimulant purgatives were reassessed, though dried rhubarb root, da huang, remains a standard ingredient of traditional Chinese medicine. Botanically the genus is placed in the Polygonaceae (Collier's "Polygonex" is a misprint), and the garden or pie plant is now usually named Rheum x hybridum, recognised as a hybrid rather than plain R. rhaponticum. The kitchen use Collier's mentions has if anything grown in prestige: forced Yorkshire rhubarb won European protected-designation status in 2010, while the leaves, high in oxalic acid, are firmly labelled inedible.
Written for this edition, 2026.