Stems - To +60cm tall, from stout taproot, herbaceous, glaucous above, with stellate and simple hairs below(dense), erect, typically simple.
Leaves - Alternate, sessile, clasping, stellate and simple pubescent. Lowest leaves 5-6cm long, 1.5-2cm broad, oblong, entire. Middle and upper leaves reduced upward, lanceolate. Auricles typically pointed.
Inflorescence - Terminal raceme, compact in flower, elongating in fruit to +30cm tall(long). Pedicels to 3mm in flower, elongating to 1.5cm in fruit, glabrous.
Flowers - Petals 4, pale-yellow, to +/-5mm long. 1.2mm broad at apex, glabrous. Stamens 6. Filaments glabrous, 3mm long. Anthers yellow, .2mm long and broad. Ovary ovoid, 2-valved. Style 1mm long, persistent in fruit and forming beak. Stigma globose.
Fruit - Obovoid silicle tapering at base, to 5mm long, 4mm in diameter, glabrous, many seeded(+/-10). Beak to 2mm long. Valves margined.
Flowering - April - September.
Habitat - Waste ground, disturbed sites, roadsides, railroads.
Origin - Native to Europe.
Other info. - This is an easily identifiable plant which you are not likely to see unless you like to walk railroad tracks. The flowers close and shrivel very quickly on sunny, warm days, so the plant is best viewed when it's overcast. Pulling the plant from the ground is an effort in futility as the taproot is quite large.