Cistanche

Growing in arid climates, cistanche is a parasitic plant that connects to the conductive system of a host, extracting water and nutrients from the roots of the host plant. Cistanche is native to the Taklimakan desert region of Xinjiang Uyghur Autonomous Region northwest China where it grows on host desert plants tamarix and haloxylon ammodendron.[1]

Along with other members of the genus, Cistanche deserticola is the primary source of the Chinese herbal medicine cistanche (Chinese: 肉苁蓉, pinyin ròucōngróng). The main sources of cistanche are Cistanche salsa and Cistanche deserticola, although it may also be obtained from Cistanche tubulosa, Cistanche sinensis, and Cistanche ambigua. The drug, known in Chinese as suosuo dayun, is collected in spring before sprouting, by slicing the stems of the plant. Cistanche deserticola has been placed on CITES Appendix 2, a list of endangered species not banned from trade but requiring monitoring. With increased consumption of cistanche, the population of the species has decreased and its area of distribution has shrunk. Aside from over-collection or indiscriminate collection, an important factor in the diminished supply of cistanche is a loss of the saxaul host, Haloxylon ammodendron, which is widely used for firewood.

Cistanche has been used as a medicine for about 1800 years and is recorded in the Shennong Bencao Jing and Bencao Gangmu as a tonic. Most of the medicinal claims have never been evaluated through clinical testing, and those claims that have been examined under controlled medical study are not supported.[2]