Annual, erect, stiffly branched, 20-50 cm tall herb, hairy with simple, rigid, reflexed hairs. Basal leaves rosulate, deeply pinnatisect with ± rounded terminal lobes, stalked, irregularly toothed; cauline leaves smaller with a narrow, often hastate terminal lobe. Racemes branched, each branch 20-30-flowered, elongated in fruit. Flowers small, c. 4 mm across, yellow; pedicels 2-4 mm long, thickened and appressed to the axis, erect. Sepals c. 2.5 mm long. Petals 3-4 mm long, 1 mm broad. Stamens c. 2: 3 mm long; anthers c. 0.5 mm long. Siliquae very short, 10-15 (-17) mm long, c. 1.5 mm broad, conical at the apex, ± hispid (rarely glabrous) ; valves rigid, 3-veined; style c. 0.5 mm long with a short, depressed stigma; septum submembranous, somewhat rigid, pale yellowish or dull whitish; seeds c. 10 in each locule, c. 0.8 mm long, ellipsoid, reddish-brown.