Annual herb, densely hispid to bristly below, glabrous above, up to 75 cm tall. Lower leaves rosetted, 5-50 x 2-15 cm, irregularly deeply serrate to more usually lyrately pinnatisect with 5-15 pairs of lateral lobes, irregularly serrate; upper leaves much reduced in size upwards, often becoming linear at the base of upper branches. Petals pale yellow, 5-7 mm long. Pods spreading to erect, up to 60 mm long with 10-20 mm long, 1-2-seeded beak.