Plants perennial, clumped and taprooted, or mat-forming and long-creeping rhizomatous. Stems: flowering shoots often decumbent proximally, 5-20(-30) cm, glandular-pubescent distally, pilose-subglabrous, deflexed or spreading proximally; non-flowering shoots present; small tufts of leaves present in axils of proximal leaves. Leaves not marcescent, sessile, ± spatulate proximally; blade linear-lanceolate to lanceolate or narrowly oblong, 4-30 × 0.5-6 mm, apex acute, rarely obtuse, subglabrous to softly pubescent, sometimes glandular. Inflorescences lax, 1-20-flowered cymes, pubescence short, glandular; bracts lanceolate, margins narrow, scarious, glandular-pubescent. Pedicels curved just below calyx, 5-30 mm, 1-6 times as long as sepals, glandular-pubescent. Flowers: sepals narrowly lanceolate to lance-elliptic, 3.5-7 mm, margins narrow, softly pubescent; petals obovate, 7.5-12.5 mm, ca. 2 times as long as sepals, apex 2-fid; stamens 10; anthers 0.8-1.1 mm; styles 5. Capsules cylindric, curved, 7.5-11.5 × 2.5-4 mm, (1-)1.5-2 times as long as sepals; teeth 10, erect, margins convolute. Seeds brown, 0.6-1.2 mm diam., tuberculate; testa not inflated. 2n = 36, 72, (108, Europe).
"Glabrous to densely villous and often glandular perennial, ascending or erect, 1.5–4(–6) dm, branched and often matted at the base; lvs linear to narrowly ovate, 2–7 cm 1–15 mm, usually subtending conspicuous axillary fascicles or short shoots; sep lanceolate, acute, 5–8 mm; pet conspicuous, white, bilobed, 2–3 times as long as the sep; polyploid series based on x=18 (or 9?). Rocky, gravelly, or sandy places, especially in calcareous or magnesian soils, often a weed in abandoned fields and meadows; throughout most of the north-temperate and boreal regions. Apr.–Aug. Highly variable, and often segregated into numerous confluent spp. or vars. (C. campestre; C. oreophilum; C. strictum; C. velutinum) An extremely villous phase on serpentine in se. Pa. and ne. Md. is var. villosissimum Pennell."
Ugborogho, R. E. 1974. North American Cerastium arvense Linnaeus. IV. Phenotypic variation. Phyton (Horn) 32: 89-97. Ugborogho, R. E. 1977. North American Cerastium arvense Linnaeus: Taxonomy, reproductive system and evolution. Phyton (Horn) 35: 169-187.
|Field or prairie mouse-ear chickweed, céraiste des champs|