Plants short-lived; taproot slender, usually with fewer basal leaves. Flowering stems branched distally, slender, (20-)30-45 cm, usually with 3-5 pairs of leaves, internodes longer than leaves. Pedicels usually several times longer than calyx. Flowers 8-12 mm diam.; calyx campanulate, 8-10(-12) mm in fruit. 2n = 48. Flowering summer. Gravelly and grassy places in the low arctic; 0-1000 m; Greenland; Man., N.W.T., Nunavut, Ont., Yukon; Alaska; Asia (Siberia). Silene ostenfeldii often appears to be inseparable from subsp. tenella except for its wingless seeds. It may be that the two subspecies of S. involucrata, together with S. ostenfeldii and S. hitchguirei, are components of a single variable species with diploid, tetraploid, and hexaploid populations.