Culms usually smooth or weakly scabrous distally. Staminate spikes 3.1-5.7 × 0.7-1.1 mm. 2n = 20-24, 30, 36.

Fruiting mid May-late Aug. Moist to dry, open or shaded, mixed and coniferous woodlands, talus slopes, ridges, rock outcrops, burns, clearings, fields, banks, snowbeds; 20-1700 m; Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., Que., Sask., Yukon; Alaska, Conn., Maine, Mass., Mich., N.H., N.Y., Vt., W.Va., Wis.

Plants recently discovered in the southern Appalachian Mountains (Georgia, North Carolina, and Virginia) have staminate spikes similar to those of Carex deflexa var. boottii, averaging larger than those of var. deflexa. They also tend to produce basal spikes more consistently than do the northern plants.