Annuals; glabrous or pubescent distal to base. Stems erect, branched distally, 1-4 dm. Basal leaves absent. Cauline leaves petiolate or (distal) sessile; blade spatulate or oblanceolate to oblong, 2-6 cm × 5-15 mm, margins pinnatifid or dentate, or (distalmost) entire or dentate. Racemes considerably elongated in fruit. Fruiting pedicels spreading to slightly descending, 3-10 mm. Flowers: sepals oblong, 1.5-3 mm; petals white or pink to purple, abaxial pair 5-8 × 2-5 mm, adaxial pair 2-5 × 1.5-3 mm. Fruits suborbicular to broadly ovate, 4-6(-7) × 3-6 mm, apically notched; valves extending into acute to obtuse wing; style 0.8-2 mm, exserted or included in apical notch. Seeds narrowly winged, 2-3 mm. 2n = 14. Flowering Jun-Aug. Escape from cultivation, waste places, old fields, lawns; introduced; N.S., Ont.; Mich.; w Europe; introduced also in South America.