Annual. Stems simple or branched, 10–50 cm, glabrous above. Basal leaves in a rosette, 1–10 cm long, oblanceolate, pinnately lobed. Stem leaves lanceolate, auriculate-clasping with dentate margins. Vestiture of simple or stellate hairs. Inflorescence an ebracteate raceme with spreading pedicels 7–12 mm long. Flowers white; petals 1–3 mm long. Fruit an obtriangular, strongly flattened silicle, 5–7 mm long with numerous seeds; style 1 mm long, deciduous (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).