Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Core eudicots
Order: Caryophyllales
Family: Polygonaceae
Genus: Rheum
Species: R. palmatum
Binomial name: Rheum palmatum
Synonyms: Rheum potaninii, Rheum qinlingense, Rhabarbarum palmatum.
Common names: Chinese rhubarb, Da Huang, Ornamental rhubarb, Turkish rhubarb, Turkey rhubarb, Indian rhubarb, Russian rhubarb

Rheum palmatum is a rhizomatous perennial with a large rootstock and thick leaf stalks. It is native to the regions of western China, northern Tibet and the Mongolian Plateau. It usually grows wild on edge of forests or grassy slopes where it is wild or cultivated. It is now grown around the world as a bold ornamental specimen. It stout rhizomes are harvested in China for conventional and herbal medicine for the treatment of a variety of medical conditions including constipation, diarrhoea, peptic ulcers, immunosuppression, high blood pressure and cancer. 

The stems are erect, about 2m high, hollow, smooth, and hairless. Its large, basal leaves are large, jagged and can have a width of up to one metre. They have a long, fleshy stalk which is of similar length with the leaf. The leaves are poisonous due to its high levels of oxalic acid. The leaf stalks are cooked and eaten like the common rhubarb.
The plant's inflorescence is a loosely branched, terminal cluster of flowers. The flowers initially bloom white/yellow and mature to a purplish red colour. The flowers are hermaphrodite (have both male and female organs) and are pollinated by wind.
The achene (a small, dry one-seeded fruit that does not open to release the seed ) is a dark brown and has 3 ridges, wings along the ridges, hollow top, and heart-shaped base.

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Flowering
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A young plant.
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Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/