Tridax procumbens L.
Linnaeus, C. (1753) Species Plantarum Edn. 1 2: 900. Type: Habitat in vera Cruce.
Stems decumbent, producing roots at the nodes, up to 50 cm tall. Stems clothed in pale hairs.
Leaf blades 30-60 x 15-35 mm, clothed in hairs, lateral veins 2-3 on each side of the midrib.Petioles hairy, 5-10 mm long.
Flowers produced in heads about 10 x 10-12 mm. Peduncles hairy,11-20 cm long. Heads surrounded by bracts, the outer bracts hairy, each bract about 7 x 4 mm, inner bracts glabrous, 7-8 mm long. Calyx (pappus) consists of barbed or fimbriate hairs 10-12 mm long. Corolla on the ray florets ligular, 9-10 x 4 mm, apex 3-lobed. Corolla of the disk florets tubular, about 5 mm long, corolla lobes about 0.5 mm long. Stamens fused to form a tube. Ovary 2-2.2 x 1 mm, densely clothed in long pale brown or golden hairs.
Achene 1.6-2 mm long; pappus of slender, plumose bristles 5-6 mm long, with fine spreading hairs.
Features not available.
This weedy species has now become widespread throughout the tropics and subtropics.
Contact with this plant can sometimes cause skin irritation (Du Puy et al. 1993)