Plants annual, taprooted. Stems erect, many-branched from base, 10-40 cm, minutely viscid-glandular; small axillary tufts of leaves usually absent. Leaves not marcescent, distal sessile, proximal spatulate; blade linear or linear- lanceolate to linear-oblong, 10-30 × 1-4 mm, apex obtuse to subacute, glabrous or sparsely and minutely viscid-glandular. Inflorescences lax, 3-21(-30)-flowered cymes; bracts narrowly lanceolate, glandular-pubescent. Pedicels erect, slender, 2-15 mm, 0.5-3 times as long as sepals, glandular-puberulent Flowers: sepals ovate-lanceolate, 5-6 mm, margins narrow, apex acute to obtuse, minutely viscid-glandular; petals oblanceolate, 5-8 mm, 1.5 times as long as sepals, apex 2-fid; stamens 10; styles 3(-4). Capsules oblong-ovoid, straight, 8-11 mm, ca. 2 times as long as sepals; teeth 6, occasionally 8, erect to spreading, margins convolute. Seeds pale brown, ovate, 0.6 mm diam., tuberculate; testa not inflated. 2n = 36, 38. Flowering spring. Alien weed of cultivated land; 200-800 m; introduced; Ark., Idaho, Ill., Ind., Kans., Ky., Miss., Ohio, Oreg., Tenn., Va., Wash.; s Europe; Asia. First collected in North America in 1966 in Washington, Cerastium dubium has now been gathered from many widely scattered sites, and appears to be spreading rapidly.
Lax, finely glandular-puberulent annual 1-3 dm; lvs 1-3 cm נ1-2 mm; fls in lax, open dichasia, the pedicels to 15 mm; bracts wholly herbaceous; sep 5, 3.5-6 mm; pet 5, about equaling or a little longer than the sep, shortly cleft; styles 3; fr 6-toothed; 2n=36, 38. European weed, casually intr. with us, as in Ill. (C. anomalum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.