One-row Yellowcress, Watercress: Nasturtium microphyllum
Watercress, Water Cress: Nasturtium officinale (Synonym: Rorippa nasturtium-aquaticum) - Flowers white. Plants aquatic with stems prostrate or floating at rooting at the nodes. Leaves pinnately compound.
Austrian Yellowcress: Rorippa austriaca
Columbia Cress, Columbia Yellowcress, Columbian Yellowcress: Rorippa columbiae (Synonyms: Nasturtium columbiae, Nasturtium sinuatum, Nasturtium sinuatum var. columbiae, Radicula columbiae, Rorippa calycina, Rorippa calycina var. columbiae, Rorippa sinuata var. columbiae) - Flowers yellow, the petals 3-5 mm long. Plants of moist sites but rarely aquatic. Fruits round to widely oblong, less than 3 times as long as wide. Plants perennials.
Abrupt Bluntleaf Yellowcress, Bluntleaf Yellowcress, Bluntleaved Yellowcress: Rorippa curvipes (Synonyms: Rorippa curvipes var. curvipes, Rorippa curvipes var. truncata) - Flowers yellow, with petals less than 3 mm long. Plants of moist sites but rarely aquatic. Fruits round to widely oblong, less than 3 times as long as wide. Plants taprooted annuals.
Curvepod Yellowcress, Lyrateleaf Yellowcress, Western Yellowcress, Western Yellow Cress: Rorippa curvisiliqua (Synonyms: Nasturtium curvisiliqua, Nasturtium lyratum, Radicula curvisiliqua, Rorippa curvisiliqua var. curvisiliqua, Rorippa curvisiliqua var. lyrata, Rorippa curvisiliqua var. orientalis, Rorippa curvisiliqua var. spatulata, Rorippa lyrata, Sisymbrium curvisiliqua) - Flowers yellow, with petals less than 3 mm long. Plants of moist sites but rarely aquatic. Fruits linear to narrowly oblong and at least 3 tims as long as wide. An annual or biennial pinnately divided but not compound leaves.
Hairy Marsh Yellowcress, Hispid Yellowcress: Rorippa palustris ssp. hispida (Synonyms: Radicula hispida, Rorippa hispida, Rorippa islandica var. hispida, Rorippa palustris ssp. hispida, Rorippa palustris var. elongata, Rorippa palustris var. hispida) -
Fernald's Yellowcress, Marsh Yellowcress, Northern Marsh Yellowcress, Smooth Marsh Yellowcress, Yellow Bogcresss: Rorippa palustris ssp. palustris (Synonyms: Rorippa hispida, Rorippa islandica ssp. fernaldiana, Rorippa islandica var. fernaldiana, Rorippa islandica var. glabra, Rorippa islandica var. glabrata,Rorippa islandica var. cernua, Rorippa islandica var. dictyota, Rorippa islandica var. glabra, Rorippa islandica var. glabrata, Rorippa palustris ssp. fernaldiana, Rorippa palustris ssp. glabra, Rorippa palustris ssp. occidentalis, Rorippa palustris var. glabra, Rorippa palustris var. occidentalis, Rorippa palustris ssp. palustris) - Flowers yellow, with petals less than 3 mm long. Plants of moist sites but rarely aquatic. Fruits linear to narrowly oblong and at least 3 times as long as wide.
Spreading Yellowcress, Western Yellowcress: Rorippa sinuata - Flowers yellow, the petals 3-5 mm long. Plants of moist sites but rarely aquatic. Fruits linear to narrowly oblong and at least 3 times as long as wide. Plants perennial from creeping rhizomes or coarse lateral roots.
Creeping Yellowcress, Shore Yellowcress: Rorippa sylvestris -
Low Yellowcress, Modoc Yellowcress: Rorippa tenerrima -