Photo Credit: Montana Statewide Noxious Weed Awareness and Education Program Archive, Montana State University, retrieved from Bugwood.org (Image Number: 2154012), used under CC BY 3.0 US, modified from the original
Common Name: Heart-Podded Hoary Cress
Scientific Name: Lepidium draba
Habitat: Roadsides, farmland, disturbed areas
Provincial Designation: Noxious
Native to Europe and Asia, it is believed that hoary cress was introduced to North America by European settlers in the late 1800s as a contaminant in grass and alfalfa seed or ballast water of ships.
Heart-podded hoary cress can invade open grasslands and form dense monocultures. It is also toxic to livestock.
Heart-podded hoary cress has 5-8 mm wide white flowers with four petals. Numerous flowers are borne at the ends of stems in flat-topped clusters.
Leaves are grey-green or blue-green in colour, elliptic or egg-shaped, and 3-10 cm long. The leaves usually clasp the stem and are covered with soft hairs. Some plants have short stalked leaves with no hairs. Most fruits are heart-shaped and flattened.
Stems are erect, hairy, and grow up to 65 cm tall.