Rorippa palustris
(L.) Besser Marsh Yellow-cressAnnual or biennial, to 60 cm high (rarely more), erect; stems often red-pigmented, glabrous. Leaves 2–12 cm long, glabrous or hairy, lobes irregularly serrate, margins toothed; basal leaves petiolate, auriculate at base, deeply incised with large terminal lamina; stem leaves similar, becoming smaller and sometimes simple. Sepals c. 1.5 mm long; petals 1–2 mm long, yellow; stamens 6. Fruit spreading to horizontal, oblong to ellipsoid, curved, 4–9 mm long (excluding style), 2–3 mm wide, contracting abruptly to style; style 0.5–1 mm long; pedicels spreading to horizontal, 4–6 mm long, glabrous or sparsely hairy; seeds in 2 rows per locule, coat covered with small bumps. Flowers mostly spring–summer.
MuM, Wim, GleP, VVP, VRiv, MSB, RobP, MuF, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, HSF, HNF, OtR, Strz, VAlp. Naturalized all States except NT. Native to much of the Northern Hemisphere. Widespread weed of wet or swampy areas.
The yellow petals about the same size as the sepals, and the short, swollen fruits are characteristic.
Entwisle, T.J. (1996). Brassicaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae, pp. 399–459. Inkata Press, Melbourne.
Spinning
