The goal of this research project is the preparation of taxonomic assessments of seed plants native and naturalized in the southeastern United States, a region defined to include North and South Carolina, Georgia, Florida, Tennessee, Alabama, Mississippi, Arkansas, and Louisiana. The focus of the research is on the relationships and classification of genera. Published treatments include descriptions, illustrations, identification keys, and an extensive, annotated bibliography, which together serve as a critical guide to the plant resources of the southeastern United States.