Cerastium vulgatum L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Short-lived perennial, perhaps sometimes blooming the first year, viscid- puberulent, 1.5–5 dm, tending to sprawl and root at the nodes, and with short, often matted, basal sterile branches; lvs ovate or lance-ovate, 1–2 cm × 3–12 mm, obtuse or acutish, the lower oblanceolate or spatulate; infl often at first compact, but becoming more open in age, the mature pedicels mostly 5–12 mm; sep 4.5–6 mm, lance- oblong, scarious-margined, without the long distal hairs of C. viscosum; pet about equaling the sep, evidently bifid, commonly to 1 mm or more; fr cylindric, often curved, 8–10 × 2–3 mm; polyploid series based on x=18 (or 9?). Native of Eurasia, now established as a weed over most of N. Amer., often in lawns. Apr.–Oct. (C. fontanum)