prairie ironweed

Sources

2, 3, 4, 5, 7, 28, 29, 30.

Subfamily
The tribe Vernonieae was formerly placed in the subfamily Cichorioideae, one of just two subfamilies of Asteraceae. It has been shown that Cichorioideae does not include all of the descendants of a common ancestor and is therefore invalid (paraphyletic). Recent molecular studies of the family Asteraceae proposed several new subfamilies. The Global Compositae Database currently recognizes fifteen subfamilies of Asteraceae, and places the tribe Vernonieae in the subfamily Vernonioideae. The placement has been widely but not universally accepted.

Some sources recongize a western subspecies Vernonia fasciculata ssp. corymbosa or variety Vernonia fasciculata var. corymbosa, including Manual of Vascular Plants (Gleason and Cronquist, 1992) (as Vernonia fasciculata var. nebraskensis), Steyermark’s Flora of Missouri (Yatskievievyck, 2006), USDA PLANTS, GBIF, NatureServe, and World Flora Online.

Other sources do not recognize any subspecies or varieties, include GRIN, Flora of North America, ITIS, NCBI, Plants of the World Online, and The Global Compositae Database.