Carduus magnificus A.Nelson accepted as Cirsium scariosum var. scariosum Nutt. (original description)
Eupatorium arizonicum (A.Gray) A.Nelson accepted as Ageratina herbacea (A.Gray) R.M.King & H.Rob. (original description)
Eupatorium occidentale var. decemplex A.Nelson accepted as Ageratina occidentalis (Hook.) R.M.King & H.Rob. (original description)
Machaeranthera magna A.Nelson accepted as Dieteria canescens var. sessiliflora (Nutt.) D.R.Morgan & R.L.Hartm. (original description)
Macronema aberrans A.Nelson accepted as Tonestus aberrans (A.Nelson) G.L.Nesom & D.R.Morgan (original description)
Senecio suksdorfii Greenm. accepted as Packera streptanthifolia (Greene) W.A.Weber & Á.Löve (original description)
Senecio websteri Greenm. accepted as Senecio neowebsteri S.F.Blake (original description)