5a. Dianthus plumarius Linnaeus subsp. plumarius
Plants cespitose, not matted. Stems erect, simple, 13-40 cm, glabrous, often glaucous. Leaves: sheath (1-)2-4 mm, 1-2 times as long as stem diam.; blade linear, 2-7.5 cm, margins glabrous, often glaucous. Inflorescences open, 2-4-flowered cymes, or sometimes flowers solitary; bracts absent; bracteoles 4, green, obovate, 4- 3 times as long as calyx, herbaceous, apex abruptly acuminate or truncate. Pedicels 8-25 mm. Flowers: calyx 40-45-veined, 14-22 mm, glabrous, lobes ovate, 3-6 mm; petals white or pale pink, often with darker center, bearded, 8-15 mm, apex divided into narrow segments to 1/ 2 as long as blade. Capsules 23-27 mm, slightly exceeding calyx. Seeds 2.4-3 mm. 2n = 30, 60, 90 (all Europe).
Flowering spring and summer. Roadsides, sandy fields; 0-400 m; introduced; N.S., Ont., Que., Yukon; Ala., Calif., Conn., Maine, Mass., Mich., Mo., N.H., N.Y., N.C., Pa., S.C., Vt., Va., Wis.; e Europe.
Subspecies plumarius is often cultivated and occasionally escapes, perhaps not persisting in the northern part of its range.