Erect, perennial herb up to 0.6 meters (2 feet) tall. Has a flat-topped appearance. Introduced from Eurasia, most likely in contaminated alfalfa seed. Also known as Lepidium draba.
• White flowers with 4 petals, approx. 1/4 inch across.
• Dense flower clusters give a flat topped appearance.
• Lower leaves are stalked and hairy while upper leaves clasp the stem and are usually hairless.
• Inflated, upside down, heartshaped seedpods.
Above ground parts are high in vitamin C.
Mowing 2–3 times a year for several years may slow the spread and reduce seed production. Mowing should be conducted during the bud stage and repeated when the plants re-bud. Selective herbicides are effective.
Reproduction and Dispersal:
Primarily by rhizomes and root fragments; can form dense patches of clones over an area of 3.6 meters (12 feet). Also reproduces by seed. Can produce two crops of seeds per year.
Meadows, fields, roadsides, ditches, waterways, cultivated lands and rangelands. Particularly adapted to sub-irrigated pastures with alkaline soils.
White flowers with 4 petals, approximately ¼ inch across. These dense flower clusters give the weed a flat-topped appearance early in the season, but this is lost as the stem elongates.
Leaves and Stems:
Leaves on mature plant are shaped like arrowheads, alternately arranged, and have finely toothed edges. Basal rosette has bluish-green, lance shaped leaves. A single stem, often branched near the top, has one flower cluster.
Inflated seedpods are shaped like an upside down heart. Seedpods contain two reddish brown, egg-shaped seeds separated by a narrow partition. Viable up to three years.
Rhizomatous, with vigorous creeping root system. Below ground buds develop new shoots. Root system comprises over 75% of the plants total biomass; can grow up to 9 meters (30 feet).
Hoary cress is an early bloomer and can easily create a dense mono culture that out-competes native plants. It is generally unpalatable to livestock.