Rheum palmatum is a species of flowering plant in the knotweed family Polygonaceae. It is commonly called Chinese rhubarb, ornamental rhubarb, Turkey rhubarb or East Indian rhubarb. Rheum palmatum is a herbaceous perennial related to the edible rhubarb. It is primarily used in traditional medicine, and as an ornamental subject in the garden. Taxonomy Agnia Losina-Losinskaja proposed classifying it in the section Palmata in the Flora SSSR in 1936. In the 1998 Flora Republicae popularis Sinicae A. R. Li maintains this classification for this species. Description Its lobed leaves are large, jagged and hand-shaped, growing in width to two feet. Chinese rhubarb has thick, deep roots. Similar species The species Rheum tanguticum is closely related to R. palmatum. R. palmatum can be distinguished from R. × hybridum, the garden rhubarb we eat, by size; while garden rhubarb only grows to a few feet in height, Chinese rhubarb can grow to six feet. Karyotypy R. palmatum has a chromosome count of 2n=22. Distribution It is native in the regions of western China, northern Tibet, and the Mongolian Plateau. Folk medicine Rheum tanguticum, R. rhabarbarum and R. officinale and a few others, are all harvested for their roots, which are used as a herbal medicine. This became one of the most prominent items traded along the Silk Road. Imported roots of various rhubarb species were widely used in Europe for hundreds of years before the identity of the plant was eventually discovered. Some of the common names associated with Rheum palmatum"Russian rhubarb", "Turkey rhubarb", and "Indian rhubarb"are directly affiliated with the trade routes for rhubarb from China. The root is known for its purported purging effects and suppressing fever. In ancient China, rhubarb root was taken to try to cure stomach ailments and as a "cathartic" (an agent used to relieve constipation), and used as a poultice for "fevers and edema" (swelling caused by fluid retention in the body tissues). It was given its Latin name by Carolus Linnaeus in the year 1759 and first grown in Britain around 1762. The first International Symposium on Rhubarb was held in China in 1990. Its objective was to verify the scientific data and treatment of Chinese Rhubarb used by Chinese pharmacopoeias. Health risks Pregnant women should avoid all intake of the plant since it may cause uterine stimulation. If taken for an extended amount of time, adverse effects include: "hypertrophy of the liver, thyroid,