Oregon's diverse wetlands are classified here informally into 15 generalized types that most people will recognize because these names are widely used by scientists and the general public. The categories are based on a combination of water chemistry, water temperature, vegetation structure, hydroperiod, and landscape position. They can be herbaceous, shrub-dominated, or forested. Some are well known, some are rarities on the landscape, and at certain times of the year some may not appear to be wetlands at all. For convenience, they are listed alphabetically.
Under each of the following headings, you will find the current classification of plant associations occurring in those wetland types. The classification was revised in 2011-2012 with support from the Oregon Department of State Lands and EPA. Nomenclature follows the PLANTS database, as used by NatureServe in the U.S. National Vegetation Classification (NVCS). Where plant associations are included in the NVCS, links are provided to descriptions and conservation ranks on the NatureServe Explorer. "Provisional" association names are those not yet included in the NVCS.
For more information on the 2012 Wetland Classification and earlier classifications see the Preface for the 2012 Wetland Classification.
Major wetland classifications: