Alternate name: Heart-pod Hoarycress
Family: Brassicaceae, Mustard view all from this family
Description An aggressive agricultural weed with flat white flower clusters above clasping toothed leaves at top of stem.
Habit: introduced perennial herb; several stout stems, erect or prostrate, branched above, softly hairy at base; rhizomatous and/or stoloniferous; may form large patches.
Height: 3-36 in (8-90 cm)
Leaf: grey-green or blue-green; at base, ovate to spatulate to lanceolate, stalked, edges sometimes toothed or shallowly lobed, prominent midvein, 0.5-6 (15-150 mm) long, to 1.6 in (40 mm) wide; on stem, alternate, smaller, clasping, oblong to arrowhead-shaped; basal leaves wither by flowering.
Flower: tiny, white, with 4 petals, to 0.2-0.4 in (5-9 mm) wide; held in flat terminal cluster.
Fruit: heart-shaped or spherical pod, flat, 2-lobed, 1/8-1/4 in (3-6 mm) long and wide; held erect or sideways on short stalk.
Flower April to August.
Habitat Mountain slopes, roadsides, fields, agricultural lands, stream sides, disturbed areas, pastures, waste areas; to 11,000 ft (3300 m).
Range Naturalized throughout North America; not found in Alaska, northern Canada, or the Southeast from North Carolina, south to Florida, west to Louisiana, north to Arkansas.
Discussion Also known as whitetop, globed-podded hoarycress, peppergrass, perennial pepper-grass, whiteweed. The latin name Lepidium draba is also used. Considered weedy or invasive in most areas; listed as noxious in 15 states; a serious problem in the western U.S. Native to Eurasia, this plant was introduced to North America via ships' ballast or contaminated cargo by the early 1900s.