Perennial, (5-) 15-30 (-45) cm tall, branched mostly from the base, erect, hoary with bipartite (rarely 3-4-parted) appressed hairs. Basal leaves densely rosulate, narrowly oblanceolate to linear-oblong, very variable in size, entire to slightly dentate, 30-50 mm long, 1.5 -2.5 (-3) mm broad; stalked to subsessile; cauline leaves linear, sessile, smaller, 1-1.5 mm broad. Racemes 20-50-flowered, up to 25 cm long in fruit. Flowers c. 10 mm across, yellow; pedicels (3-) 5-10 mm long in fruit, slightly thickened. Sepals 6-8 mm long. Petals (10-) 12-15 mm long, 5-6 mm broad. Stamens 6-7: 8-9 mm long; anthers c. 2 (-2.5) mm long. Siliquae (25-) 40-60 (-80) mm long, 1.5-2 mm broad, linear-oblong, terete, erect to sub-spreading, straight, appressedly hairy; valves with a prominent mid-rib; style 1.5-3 mm long, with capitate, subbilobed stigma; septum slightly rigid; seeds c. 2 mm long, 1 mm broad, oblong-ellipsoid, with or without an obscure wing to-wards the apex.