Herbaceous riparian vegetation occurs along rivers and streams throughout the state. It is often in or along active stream channels, and intergrades with upland portions of floodplains in a jumble of units that are difficult or impossible to map separately. It also intergrades with forested and shrub riparian vegetation, usually occurring as openings among these other types. It differs from the other habitat categories by having a relatively small patch size and moving water. Substrates are cobbles, boulders, sand, silt, and woody debris. Hydration may come from seasonal flooding by streams and rivers, or perennial streams and groundwater.

Herbaceous riparian map

Habitat: Edges and channels of rivers and streams, or interior portions of floodplains
Water regime: Perennially to seasonally flooded
Water chemistry: Fresh

Ecoregion*: BM = Blue Mountains, BR = Northern Basin and Range, CB = Columbia Basin, CR = Coast Range, EC = East Cascades, KM = Klamath Mountains, WC = West Cascades, WV = Willamette Valley
	Scientific & Common Name	Global & State Rank	Ecoregion*
	Adiantum aleuticum Wet Herbaceous Riparian [Provisional] Northern maidenhair fern (McCain 2004: 150; Crowe et al. 2004: 152)	G4S3	BM, WC
	Artemisia ludoviciana Herbaceous Riparian [Provisional] Prairie sage (Crowe et al. 2004: 157; Wells 2006: 159)	G4S2	BM
	Athyrium filix-femina - Glyceria striata - Senecio triangularis [Provisional] Lady fern - fowl mannagrass - arrowleaf groundsel (Crowe et al. 2004: 156)	G4S3	BM, EC, WC
	Boykinia occidentalis - Mitella ovalis Herbaceous Riparian [Provisional] Slender boykinia - oval leaved mitrewort (McCain 2004: 61)	G4S3	WC
	Carex nudata Wet Herbaceous Riparian [Provisional] Torrent sedge (Crowe et al. 2004: 108)	G3S3	BM, CB
	Chrysosplenium glechomifolium Wet Herbaceous Riparian [Provisional] Western golden carpet (McCain 2004: 188)	G3S3	CR
	Corydalis aquae-gelidae Wet Herbaceous Riparian [Provisional] Clackamas corydalis (McCain 2004: 46)	G3S2	WC
	Equisetum arvense Wet Meadow Common horsetail (Murray 2000: 18; McCain 2004: 185; Christy 2004: 117; Crowe et al. 2004: 159; NS)	G5S5	BM, CR, EC, WC, WV
	Erythranthe guttata Wet Herbaceous Riparian [Provisional] Yellow monkeyflower (McCain 2004: 43, 44)	G3S2	WC
	Erythranthe guttata - (Erythranthe spp.) Wet Herbaceous Riparian [Provisional] Tiling's monkeyflower - great purple monkeyflower (McCain et al. 2014: 266; NS)	G3S2	WC
	Oxalis - Hydrophyllum tenuipes - Tolmiea menziesii Herbaceous Riparian [Provisional] Oxalis - Pacific waterleaf - piggyback plant (McCain 2004: 116, 196)	G3S3	CR, WC
	Petasites frigidus - Equisetum arvense Wet Herbaceous Riparian [Provisional] Sweet coltsfoot - common horsetail (McCain 2004: 53)	G4S4	WC
	Petasites frigidus - Stachys cooleyae Wet Herbaceous Riparian [Provisional] Sweet coltsfoot - great betony (McCain 2004: 56)	G4S4	WC

Authored by John A. Christy, Wetlands Ecologist, (ORBIC) Oregon Biodiversity Information Center (2017)