Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California, Arizona, and Texas eastward and northward to the Atlantic Coast.
Habitat: Roadsides, gardens and wasteland.
Flowers: May-July
Origin: Introduced from South America (or possibly Eurasia)
Growth Duration: Annual, Biennial
Conservation Status: Not of concern
Pollination: Ants
Low, spreading, glabrous to scurfy-pubescent annual, the stems freely-branched, decumbent, 2-5 dm. long.
Leaves alternate, numerous, ovate-oblong, 1.5-3 cm. long, pinnatifid, the segments narrow, entire to pinnatifid.
Inflorescence of many-flowered, crowded, axillary, bractless racemes 1-4 cm. long; pedicles slender, 1.5-2.5 mm. long; sepals 4, spreading, 0.5 mm. long, deciduous; petals 4, white, linear, minute; stamens 2.
Silicles strongly wrinkled, 2 mm. broad and 1.5 mm. long, cordate and notched, inflated and slightly obcompressed.
Publication: Syst. Nat. ed. 12. 2: 433. 1767; Mant Pl. 1: 92. 1767.
PNW Herbaria: Specimen records of Lepidium didymum in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Lepidium didymum checklist entry.
OregonFlora: Lepidium didymum information.
E-Flora BC: Lepidium didymum atlas page.
CalPhotos: Lepidium didymum photos.
USDA Plants: Lepidium didymum information.
