Bot. Gaz. 16: 44, plate 6, figs. 9–11. 1891.
Plants perennial, cespitose, with decumbent subterranean shoots; taproot stout; caudex branched, woody. Stems numerous, erect, simple, 3–15 cm, pubescent, viscid-glandular distally. Leaves mostly basal, densely tufted; basal numerous, pseudopetiolate, blade narrowly oblanceolate, tapering into base, 0.5–3 cm × 1.5–4 mm, ± fleshy, apex acute, puberulent; cauline in 1–3 pairs, ± sessile, reduced, blade narrowly oblanceolate to linear-lanceolate, 0.7–2 cm × 1–3 mm, apex acute, puberulent. Inflorescences: flowers terminal, solitary, or in single dichotomy, bracteate; bracts leaflike, 3–15 mm. Pedicels erect, ca. equaling calyx, viscid glandular-pubescent, hairs with purple septa. Flowers: calyx prominently 10-veined, campanulate, not contracted proximally around carpophore, 10–15 × 5–7 mm, papery, veins parallel, purplish, with pale commissures, with purple-septate glandular hairs (rarely septa not purple), lobes ovate, ca. 2 mm, margins broad, membranous, apex obtuse; corolla off-white or tinged with dusky purple, clawed, claw equaling calyx, broadened distally, limb 2-lobed, 3–5 mm, appendages ca. 1 mm; stamens equaling calyx; styles 3(–4), equaling calyx. Capsules equaling calyx, opening by 6 (or 8) teeth; carpophore 2.5–3.5 mm. Seeds brown, broadly winged, reniform, 1–2 mm, rugose-tessellate. 2n = 48.
Phenology: Flowering summer.
Habitat: Alpine ridges, gravel slopes, talus
Elevation: 1600-3000 m
Calif., Oreg., Wash.
Silene suksdorfii appears to be closely related to S. parryi but differs in its broadly winged seeds, smaller size, cespitose habit, and the prominent purple-septate hairs of the calyx, although the latter occasionally are present in S. parryi. It is very similar to, and in Idaho appears to intergrade with, another alpine species, S. sargentii, which has linear leaves and lacks the purple septa in the hairs and the broad wing on the seeds. It is similar also to S. hitchguirei; see discussion under that species.