This classification of riparian and wetland plant communities in the Shoshone National Forest was a cooperative project between the Wyoming Natural Diversity Database (WYNDD) of The Nature Conservancy and the Shoshone National Forest. This project identifies groups of plant species that commonly occur together in particular environmental settings, Each such group of species, or plant community type, is identified by the structure of the vegetation and by the species contributing the most canopy cover. The classification identifies physiognomic types based on the amounts of trees, tall shrubs, low shrubs, and herbaceous plants; and dominance types within each physiognomic type. The term "community type" is used in a broad sense to mean both seral or successional vegetation types and potential or climax vegetation types.