Plants not scapose; pubescent or glabrous. Stems often erect, sometimes ascending, rarely subprostrate or decumbent, often branched distally, sometimes unbranched. Leaves basal and cauline; petiolate or sessile; basal rosulate or not, petiolate, blade margins dentate, sinuate, lyrate, runcinate, or pinnately lobed [entire]; cauline similar to basal, (blade smaller distally). Racemes (several-flowered), often considerably elongated in fruit. Fruiting pedicels ascending, divaricate, or erect, slender or stout (sometimes as wide as fruit). Flowers: sepals ovate or oblong, (glabrous or pubescent); petals yellow, obovate, spatulate, oblong, or suborbicular, (longer than sepals), claw differentiated from blade, (subequaling or longer than sepals, apex obtuse or emarginate); stamens tetradynamous; filaments not dilated basally; anthers oblong, (apex obtuse); nectar glands confluent, subtending bases of stamens, median glands present. Fruits usually sessile, rarely shortly stipitate (gynophore to 1 mm), usually linear, rarely lanceolate or subulate, smooth or torulose; valves each with prominent midvein and 2 conspicuous marginal veins, usually glabrous, rarely pubescent; replum rounded; septum complete; style subclavate [clavate, conical, cylindrical]; stigma capitate (lobes not decurrent). Seeds plump, not winged, oblong [ovoid]; seed coat (reticulate or papillate), not mucilaginous when wetted; cotyledons incumbent. x = 7.
Sep obtuse, ascending; pet small, yellow, obovate to spatulate, gradually narrowed to the claw; glands of the short stamens usually annular; filaments slender; anthers oblong; ovary cylindric; style short, scarcely differentiated; stigma capitate; ovules numerous; frs elongate, linear or subulate, terete or slightly quadrangular, tipped with the minute, persistent style; valves 3-nerved, with conspicuous midnerve and thinner lateral nerves; seeds in one row, oblong, smooth or nearly so; ours annuals or winter-annuals, ±pubescent with simple hairs, at least the lower lvs deeply pinnatifid. 90, widespread.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.