Xu Duan

Dipsacus asperoides, Chinese teasel or Xu Duan, is a robust perennial herb in the Caprifoliaceae (formerly Dipsacaceae) family, native to central and southwestern China where it grows on grassy slopes and forest margins between 800-3000 m elevation. The plant reaches 1-2 m in height with sparsely prickly, ridged stems. Basal leaves are large and pinnately lobed; stem leaves are opposite, lanceolate to oblong, with toothed margins and prickly midribs. Dense globose flower heads 2-3 cm across, ringed with stiff involucral bracts, bear small white to pale purple tubular florets. The thick, fleshy taproots are harvested in autumn.