| Author | (L.) Besser | |
| Distribution | Throughout the state, though possibly absent along the eastern coastal areas.
This species occurs across the U.S. and southern Canada. | |
| Abundance | Infrequent to locally fairly common; despite it occurring 3/4th of the counties with specimens, it is not a common species, though a State Rank of S5 is certainly warranted. | |
| Habitat | This is a wetland species of varied habitats, but always in standing or very slowly moving water, and usually in sunny places. It grows along sreamsides, seepages, margins of lakes and ponds (especially in drawdown zones), marshes, ditches, and other similar places. | |
| Phenology | Blooms from May to October, and fruits shortly after flowering. | |
| Identification | This is a fairly robust species with a broad stem, up to 2-3 feet tall, sometimes branched. The basal leaves, flat on the ground, are pinnately divided, with the terminal lobe usually elliptical to ovate and 1-inch or more long and wide; lateral lobes are narrow. It has numerous stem leaves, alternate, and highly dissected into pinnate segments, the lobes somewhat rounded but lightly serrated. There are a number of racemes of flowers from upper axils and the end of the stem, with lateral ones usually spreading horizontally. The petals are small but bright yellow. In this species, the flowers are on pedicels, and petals are present; in R. sessiliflora, the flowers are nearly sessile, and petals are absent. This is a "horsey" wetland plant, with many pinnately divided leaves and numerous racemes (often more like rounded clusters) of bright yellow flowers. | |
| Taxonomic Comments | Most older references named it as Rorippa islandica. There are several varieties, of which only the nominate one occurs in NC.
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| Other Common Name(s) | Marsh Yellowcress, Yellow Marshcress | |
| State Rank | S4 [S5] | |
| Global Rank | G5 | |
| State Status | | |
| US Status | | |
| USACE-agcp | OBL link |
| USACE-emp | OBL link |
