Distribution: Occurring west of the Cascades crest in lowland western Washington British Columbia to Oregon, east to Montana, Wyoming, Nebraska, the Great Lakes region, and northeastern North America.
Habitat: Fields, roadsides, and wastelots at low elevation.
Flowers: April-May
Origin: Introduced from Europe
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Self-pollination, bees, flies
Rhizomatous, mat-forming perennials, the flowering stems ascending, branched, 15-40 cm. long; non-flowering stems prostrate, readily rooting; herbage densely white-woolly.
Leaves opposite, sessile, linear to linear-lanceolate, 10-60 mm. long and 2-8 mm. wide, not glandular.
Inflorescences of lax, 3- to 13-flowered, bracteate cymes; pedicles ascending, straight, 10-40 mm. long; flowers white, 12-20 mm. in diameter; sepals 5, narrowly lanceolate-elliptic, 5-7 mm. long; petals 5, deltoid, 2 lobed, white, 10-18 mm. long; stamens 10; styles 5.
Capsules cylindric, slightly curved, 10-15 mm. long, with 10 erect teeth.
PNW Herbaria: Specimen records of Cerastium tomentosum in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Cerastium tomentosum checklist entry
OregonFlora: Cerastium tomentosum information
E-Flora BC: Cerastium tomentosum atlas page
CalPhotos: Cerastium tomentosum photos