|Dicotyledon|| Literature for Tridax procumbens
Wagner et al., 1990, 1999; Lorence & Wagner, 2020.
|Asteraceae -- The Sunflower Family||Bibliography|
Common name(s): coat buttons
|Distribution||Apparently native only from Mexico, Central America, Venezuela, Colombia, Peru, and Bolivia, but now widespread throughout tropical and subtropical regions of the world.In the Hawaiian Islands, naturalized on Midway, Ni`ihau, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Kaho`olawe, Hawai`i.|
||Taprooted, perennial herb; stems ascending to procumbent, often rooting at the nodes, 1.5‒4 dm long, sparsely to densely hirsute.
||Leaves short-petiolate; blade ovate to lanceolate, 2‒7(‒12) cm long, 1‒4(‒6) cm wide, both surfaces sparsely to densely hirsute and often rough to the touch, 3-lobed, margin undulate; petiole 0.4‒3 cm long.
||Heads campanulate, solitary on long peduncle (7‒)10‒18(‒20) cm long; involucral bracts 3.5‒6.5(‒8) mm long; ray florets 3‒6 per head, rays white, rarely pale yellow, 2.5‒4(‒5) mm long; disk corollas pale yellow, 5‒6.5(‒7) mm long; pappus of ca. 20 plumose bristles unequal in length, that of ray florets reduced.
||Achenes black, cylindrical to narrowly obconical, 2‒2.5 mm long, densely pilose.
||2n = 36