[1] Eupatorium triplinerve M.Vahl[1] Ayapana triplinervis (aya-pana, water hemp) is a tropical American shrub in the family Asteraceae.

[1] The flowers are pale pink and the thin, hairless stem is reddish in color.

Its leaves are purple, subsessile, lanceolate, 3-nerved, acuminate, subentire, and glabrous.

[citation needed] This oil contains the coumarins ayapanin (herniarin) and ayapin, as well as other chemical compounds including stigmasterol, vitamin C, and carotene.

[2] The plant yields cineol, α-phellandrene, alpha-terneol, ayapanin, ayapin, borneol, coumarin, sabinene, and umbelliferone, among many others.