Plants annual; taproot slender. Stems erect, simple or branched, slender, to 80 cm, subglabrous to retrorsely puberulent especially proximally, distal internodes frequently glutinous. Leaves 2 per node; blade with margins ciliate toward base, apex acute to obtuse; basal blades oblanceolate, spatulate; cauline narrowly oblanceolate to linear, 1-9 cm × 2-15 mm, scabrous or puberulent, rarely glabrous on both surfaces. Inflorescences cymose, open, branches usually ascending, several- to many-flowered, 1-flowered in depauperate specimens. Flowers: mature calyx prominently 10-veined, campanulate to ovate, 5-9 × 3-5 mm, margins dentate, glabrous, veins parallel, with pale commissures; lobes usually purple, triangular, acute, ca. 1 mm; petals white, often suffused with dark red, rarely wholly dark red, limb ovate, usually 2-lobed, ca. 2.5 mm, slightly longer than calyx, rarely petals absent, claw narrow, appendages 0.1-0.4 mm; stamens included; styles 3; stigmas included. Capsules equaling calyx, opening by 6 teeth; carpophore less than 1 mm. Seeds dull gray-black, reniform, 0.5-0.8 mm diam., finely papillate. 2n = 24. Flowering spring-late summer. Dry, sandy or gravelly places, roadsides, fields, waste places, open woods, often appearing after burning; 0-2300 m; Alta., B.C., Man., N.B., Ont., Que., Sask.; Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Mexico; South America; adventive in Europe. The six varieties and forms of Silene antirrhina noted above were named on the basis of stature and flower color, but none appear to be worthy of recognition. The species is very plastic, being greatly affected by moisture, exposure, and nutrients.
Annual, 2-8 dm, often puberulent below, glabrous above except usually for some glutinous bands below the upper nodes; basal lvs oblanceolate to spatulate; cauline lvs oblanceolate to linear, 3-6 cm נ9-12 mm, the margins ciliate near the base; infl open; fls mostly ±numerous; cal 4-10 mm, 10-nerved; pet white or pink, equaling or exceeding the cal, 2-lobed, or obsolete, the appendages minute or none; carpophore 1 mm; fr 4-10 mm, 3-locular; seeds 0.5-0.8 mm wide, papillate; 2n=24. Sandy soil and waste places, through the U.S. and s. Can., apparently native. Summer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.