Winter cress is an introduced Eurasian biennial that is now a very common weed of roadsides, meadows, mudflats or any disturbed area, whether dry or moist. The plants grow up to 0.5 m tall.
Origin of the name: Barbarea, after St. Barbara; vulgaris, L. vulgaris, common, ordinary
Range: N. Temperate Zone
WI Range: Common throughout southern WI; locally north to Bayfield and Iron Counties
Common associates: Brome grass, kentucky bluegrass, wild carrot, ragweed
Wetland Indicator Status: FAC
Coefficient of Conservatism: C = * (S&W), C = * (MI)
bloom in spring from May to early June.
Like all mustards, the flowers have 4 petals, each bent outward in the middle forming a cross; and 6 stamens, 4 long and 2 short. The petals are 4 to 8 mm long. The seeds form in a 2 to 3 cm linear capsule (silique). Also like most mustards (broccoli, cabbage, etc.) its sharp taste is due to sulfur absorbed from the soil and metabolized into an oil in the leaf and seed tissue.
Foliage is dark green and glossy. The basal leaves are pinnate with a large rounded terminal lobe; upper leaves are oval and clasp the stem.
Winter cress is similar to the equally common and
invasive Wild Mustard (Brassica kaber), also with yellow flowers. Wild Mustard is a summer blooming annual whose upper leaves are toothed but not lobed and the leaves donít clasp the stem.