1081. Parthenium integrifolium L.: Compositae.

The North American Prairie plant, L. (Compositae: Heliantheae: Ambrosiinae) is described and illustrated. Related genera in the subtribe are commented on, as well as the better‐known species, A. Gray, the , and infrageneric taxonomy within L., in addition to the characteristics of the genus. Aspects of cultivation, propagation, pests and diseases and availability for are also noted. A full synonymy of this rather variable species is provided, together with type citations, locations of known types, and related commentary. The distribution, habitat and ecology, phenology, common names and conservation status are stated or discussed, together with comments on usage, and the species' roots being used as an adulterant in preparations of (L.) Moench.