What is Ox-Knee Root or Radix Achyranthis Bidentatae?

Origin of Ox-knee root.

Ox-Knee Root Extract Achyranthes bidentata Bl Radix Achyranthis Bidentatae Twotooth Achyranthes Root Cyathula Root Chuan Niu Xi Szechwan Ox Knee Root Extract photo picture image The root of Achyranthes bidentata Blume., a perennial plant, of the family Amaranthaceae. Native to east Asia, the plant is grown in forest edges, the sides of streams and shrubberies in China and Java.

The perennial plant grows to about 0.75 m by 0.4 m. It is in flower from August to September. The flowers are hermaphrodite (have both male and female organs). The plant can grow in semi-shade (light woodland) or no shade. It requires moist soil.

In China, the plant is mainly produced in the provinces Henan, Sichuan, Guizhou, Yunnan, etc. The root is harvested from 1 or 2 year old plants in the autumn or winter and usually dried in the sun and ground into a powder, used in decoctions or after being fried with wine.

Slender and cylindrical, sometimes slightly curved; thicker at the top end and tapering towards the bottom; 15-90 cm long; 0.4-1 cm in diameter. Outer surface greyish-yellow or pale brown, marked with twisted, fine longitudinal wrinkles, lalongate (transversely elongated) lenticels and sparse rootlet scars. Hard and brittle; breaks easily, softens when moistened. When broken, surface even; yellowish-brown; slightly cuticular oily and soft; medial xylem at centre of surface relatively large and yellowishwhite; under magnification, 2-4 rings of numerous punctiform (dot-like) vascular bundles scattered around xylem. Odour: faint; taste: slightly sweet and a little bitter-astringent.