Biennials or, rarely, perennials; mostly glabrous, except blade auricles ciliate. Stems (1-)2.5-8 dm. Basal leaves: petiole (0.5-) 1-6(-8) cm; blade pinnatifid to pinnatisect, 1.5-11 cm, lobes (3-)6-10 on each side, lateral lobes oblong or ovate, 0.4-3 cm × 1-10 mm, not fleshy, margins entire, terminal lobe considerably larger than lateral ones, 1-5 cm × 10-350 mm. Cauline leaves: blade pinnatisect, lateral lobes 1-4, (oblong to lanceolate), margins often entire, rarely coarsely toothed; conspicuously auriculate, auricles ovate or narrowly oblong, (to 10 × 4 mm, margins entire). Fruiting pedicels divaricate to ascending, (2-)3-6(-7) mm, terete, stout (almost as broad as fruit). Flowers: sepals 3-5 × 0.7-1.5 mm, lateral pair slightly saccate basally, margins scarious; petals yellow or pale yellow, oblanceolate to spatulate, (5-)6-7(-8.5) × 1.5-3 mm, base cuneate, apex truncate or emarginate; filaments 3-5 mm; anthers 0.8-1.2 mm; ovules (34-)38-48(-52) per ovary; gynophore to 0.3 mm. Fruits erect to ascending, not appressed to rachis, torulose, subterete to slightly latiseptate, (4.5-)5.3-7(-8) cm × 1.5-2 mm; style stout, 0.2-1(-2) mm. Seeds dark brown, somewhat plump, oblong or quadrate, 1.8-2.5 × 1.4-1.6 mm. 2n = 16. Flowering Mar-Jul. Waste grounds, fields, limestone glades, rocky outcrops, fields, railroad embankments, disturbed sites, roadsides; 0-1600 m; introduced; B.C., Nfld. and Labr. (Nfld.); Ala., Alaska, Ark., Calif., Colo., Conn., Del., D.C., Ga., Ill., Ind., Ky., Maine, Md., Mass., Mich., Miss., Mo., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., S.C., Tenn., Va., Wash., W.Va.; Europe; Asia; n, s Africa; introduced also in Mexico, South America (Argentina, Brazil, Chile), Australia.