Eupatorium has recently undergone some revision and has been broken up into smaller genera. Joe Pye weeds were initially included in the genus
Eupatorium, but as early as the 19th century Franco-American botanist
Constantine Samuel Rafinesque proposed separating them into their own genus
Eutrochium. Unaware of this, This was widely accepted, and Joe Pye weeds began to be referred to as such. This decision was also widely accepted. Based on chloroplast DNA analysis published by Edward E, Schilling et al. in 1999, the Joe Pye weeds were again separated into their own genus,
Eutrochium, as
Eutrochium is the
senior synonym of
Eupatoriadelphus. This usage quickly became formalized.
Eupatorium and
Eutrochium are both placed in the
subtribe Eupatoriinae, but South American plants which have sometimes been placed in that subtribe, such as
Stomatanthes, seem to belong elsewhere in the tribe
Eupatorieae. •
Eutrochium dubium (Willdenow ex Poiret) E. E. Lamont – coastal plain Joe-Pye weed •
Eutrochium fistulosum (Barratt) E. E. Lamont – hollow Joe-Pye weed •
Eutrochium maculatum (Linnaeus) E. E. Lamont – spotted Joe-Pye weed •
Eutrochium purpureum (Linnaeus) E. E. Lamont – sweet Joe-Pye weed, green-stemmed Joe-Pye weed, queen of the meadow, gravel root, kidney root, purple boneset •
Eutrochium steelei (E. E. Lamont) E. E. Lamont == Uses ==