Xiao Ji

Cirsium setosum (Willd.) M.Bieb. (Asteraceae), sometimes treated as Cirsium arvense var. setosum or Breea setosa, is a rhizomatous perennial herb of fields, roadsides, ditches and disturbed ground across much of temperate Eurasia. It spreads aggressively by deep, branching white horizontal roots, producing erect, ribbed, sparingly branched stems 30 to 100 cm tall that are smooth to slightly cobwebby and not strongly spiny on the stem. The leaves are alternate, sessile, oblong-lanceolate to oblong, 5 to 15 cm long, with shallowly toothed to pinnately lobed margins armed with weak yellow-brown spines, smooth above and finely arachnoid-tomentose beneath. The plant is dioecious; flower heads are borne in loose terminal clusters, each head 1.5 to 2.5 cm across with an ovoid involucre of overlapping bracts and a brush-like tuft of pale lilac to pink-purple disc florets and feathery pappus, with no ray florets. The fresh or dried whole plant in flower constitutes Xiao Ji.