Da Xue Teng

Sargentodoxa cuneata is a large woody deciduous climbing vine in the monotypic family Sargentodoxaceae (sometimes placed in Lardizabalaceae), native to broadleaf forests of central and southern China and northern Indochina. The twining stems can reach 10 metres or more in length and exude a reddish sap when cut, with a distinctive radial pattern of conspicuous medullary rays visible in cross-section. Leaves are alternate, long-petiolate, trifoliolate, with a larger ovate terminal leaflet and two oblique lateral leaflets. The plant is dioecious; small yellow-green unisexual flowers hang in pendulous racemes, followed by clusters of fleshy blue-black berries on a thickened receptacle. The dried sectioned stems harvested in autumn constitute the medicinal Da Xue Teng.