This list is based on Christy et al. (1982) and supersedes any online versions posted prior to the date shown above. Additions to the flora since 1982 are marked by asterisks, with the earliest known verified sources noted in square brackets. Unless noted otherwise, nomenclature conforms to Flora of North America Volumes 27 and 28. Most family placements follow Goffinet et al. 2014. For convenience, synonyms used by Lawton (1971) and more recent works are provided in square brackets. In general, sources for nomenclatural changes can be found in the TROPICOS database. The checklist is followed by annotated lists of taxa excluded from the flora, and taxa expected to occur in Oregon that have been reported from neighboring states. A growing amount of specimen label data are now accessible online from the the Consortium of Pacific Northwest Herbaria and the Consortium of North American Bryophyte Herbaria, but these records have not necessarily been verified recently. Increasingly, it is possible to identify the original specimens upon which historical reports were based (Christy et al. 1982; Christy 1983), but all old material needs to be reconfirmed by critical study.