银胶菊 yin jiao ju

Herbs, annual, 30-120 cm tall. Leaf blade ovate to elliptic, 3-18 × 1-5(-9) cm, pinnately (1 or)2-lobed, ultimate lobes lanceolate to linear, 3-50 × 2-15 mm, both surfaces sparsely to densely scaberulose and gland-dotted. Synflorescences of open panicles. Capitula obscurely radiate; peduncles 1-8(-15+) mm; outer phyllaries 5(or 6), elliptic-lanceolate, 2-4 mm, inner 5(or 6) ovate to orbicular, 2.5-4 mm. Female florets 5(or 6); corolla limbs reniform or orbicular to oblong, 0.3-1 mm. Disk florets 12-30(-60). Achenes obovoid, 1.5-2(-3.5) mm; pappuslike enations erect, deltate to ovate, 0.5-1 mm. Fl. Apr-Aug. 2n = 34.

Fields, roadsides; below 1500 m. Guangdong, Guangxi, Guizhou, Yunnan [native to tropical America; a widely introduced weed in the tropics].