Idaho land managers and regulators need knowledge on riparian reference sites. Reference sites are ecological controls that can be used to set meaningful management and regulatory goals. Since 1984, the Idaho Conservation Data Center, Boise, ID, has compiled information in a series of interrelated databases on the distribution and condition of riparian, wetland, and terrestrial plant associations in high quality reference sites in Idaho. This report summarizes association-specific and reference area-specific information from our databases and presents a standardized classification of Idaho riparian and wetland plant associations. Each plant association entry includes the current global and state conservation rank, and the plant association's occurrence in reference areas (if any). This is followed by a summary of each reference area, arranged by ecoregional Province and Section. Summary information includes location, management responsibility, site description, and a list of all riparian and wetland associations that occur in the area.