Widespread. Africa, Asia, North, South and Central America, Caribbean, Europe, Oceania. In most Pacific islands.
Important invasive, creeping, perennial weed of forests, forest margins, open woodlands, wetlands, roadsides, waste areas, and coastal vegetation, forming extensive, dense, ground cover, crowding out other species.
Up to 70 cm tall; stems green, up to 2 m long, sometimes hairy. Leaves, three lobes (centre one larger), paired along stem, glossy, with saw-like margins, without leaf stalks. Flowerheads, bright yellow, daisy-like, borne singly off side branches, 20-30 mm across, each with 8-13 flowers at the margin, with yellowish petal-like leaves; smaller flowers at the centre.
Spread: stems or stem fragments (moved in waste or flood water) that readily form roots; moved as an ornamental.
Biosecurity: high risk of introduction. In Australia, 'restricted invasive plant': do not release into environment, give away or sell. Among 100 of World's Worst Invasive Alien Species (IUCN, 2020).