Tou Gu Cao

Speranskia tuberculata is a slender perennial herb of the family Euphorbiaceae endemic to northern and central China, where it grows on dry grassy slopes, stony banks and roadsides at low to mid elevations. From a short woody rootstock it produces several erect or ascending stems 20-50 cm tall, finely puberulent and often tinged purple at the base, bearing alternate, short-petiolate, lanceolate to oblong-lanceolate leaves 2-5 cm long with shallowly crenate-serrate margins and slightly tuberculate surfaces. The monoecious inflorescences are slender terminal racemes 5-15 cm long bearing small staminate flowers in the upper part and a few pistillate flowers below, both apetalous with five greenish sepals. The fruit is a three-lobed, tuberculate capsule about 3 mm wide containing globose grey-brown seeds. The whole flowering herb is collected in summer.