Family names and species assignments to families follow Yatskievych et al. (in prep.) Indiana Vascular Plants Catalog. They are based primarily on the APG III system (Angiosperm Phylogeny Group III system) of flowering plant classification published in 2009. The APG III system reflects plant relatedness based primarily on evolutionary relationships derived from molecular data.
Traditional Family names are primarily based on those used for species in Gleason and Cronquist's Manual of the Vascular Plants of the Northeastern United States and Canada. These are the names many students of botany learned and they are still useful for recognizing related species in the field.