Annual herb with lax rosette. Stems erect, glabrous, to 1-(2) m tall. Lvs glaucous, glabrous or sparsely hairy, all petiolate. Lower lvs lyrate-pinnatifid to lyrate-pinnate, with large terminal and 1-2 pairs of lateral lobes, 8-15-(20) × 5-8 cm; margins dentate. Upper lvs simple, becoming linear, toothed to entire, 20-50 × 3-10 mm. Racemes to 45 cm long; open fls about level with buds, or lower. Sepals erecto-patent, narrow-oblong, 4-6 × c. 1 mm. Petals yellow, 6-8 × 2-3 mm. Lateral stamens spreading. Silique terete, glabrous, linear, constricted between seeds, 15-25-(40) × 1.5-2.5 mm; gynophore 0; valves with prominent median and weaker lateral veins; beak tapering, seedless, 5-10 mm long. Seeds yellow to brown, 1-2 mm diam.