Chenopodium ambrosioides Linnaeus

Strongly aromatic, annual to short-lived perennial, variously pubescent especially on stem, and with sessile yellow glands especially on lower leaf surfaces. Stem to 80(-120) cm, ± erect, branches long, ascending. Leaves with 1 cm long petiole; blade 5-10 cm, lanceolate to elliptic, irregularly coarsely serrate, sometimes shallowly sinuate to almost entire, attenuate at base, acute to obtuse at apex; bracts entire, linear - lanceolate - narrowly obovate, uppermost very small. Inflorescence paniculate, flowers sessile in small, dense glomerules usually subtended by bracts and arranged spicately. Terminal flowers bisexual, perianth deeply 5-lobed, lobes cucullate, stamens usually 5; lateral flowers female, perianth connate, 5-toothed; teeth roundish on back; perianth herbacous, glabrous to sparsely pubescent. Stigmas usually 3-4, long, slender. Fruits falling with perianth. Pericarp free. Seeds mostly horizontal, sometimes oblique or vertical, brown, 0.6-0.8 mm in diameter, somewhat ovate to circular in outline, margin obtuse; testa almost smooth, sometimes with obscure shallow pits.

Almost cosmopolitan; weed and relic of cultivation.

Distribution: Probably originating from tropical America. Earlier cultivated as medicinal plant and introduced in tropical and subtropical areas of the world, where it is commonly naturalized.

300-2600 m

Fl. & Fr. Per.: April - January.

Field margins, gardens, yards, roadsides, stream sides.- s.l. 1430 m.

Ambrina ambrosioides Spach in Hist. Nat. Veg. 4: 297. 1836; Chenopodium integrifolium Vorosch., Bot. Zhurn. 27: 42. 1942; Chenopodium suffruticosum Willd., Enum. Pl. Hort. Berol.: 290. 1809.