Rep. (Annual) Regents Univ. State New York New York State Mus. 47: 166. 1894.
Plants loosely cespitose; rhizomes ascending, reddish-brown, 0–15 (–30) mm, slender. Culms 21–47 cm, smooth to weakly scabrous distally; bases not fibrous. Leaf-blades pale green, shorter than culms, 1–3.3 mm wide, herbaceous, papillose abaxially, scabrous adaxially. Inflorescences with both staminate and pistillate spikes; peduncles of staminate spikes 0.4–2.2 mm; proximal cauline bracts leaflike usually shorter than inflorescences. Spikes: proximal pistillate spikes 2–3 (basal spikes 0); cauline spikes with proximal 2 spikes overlapping, se!parated by less than 7 mm, with 3–10 perigynia; staminate spikes 5.3–8.6 × 0.8–1.7 mm. Scales: pistillate scales reddish-brown to pale-brown, with broad white margins, ovate, 2.2–3.2 × 1.2–1.8 mm, 1/2 to 2/3 length of perigynia, apex acute to acuminate,; staminate scales elliptic, 2.4–3.2 × 0.9–1.8 mm, apex acute. Anthers 1.4–1.5 mm. Perigynia light green, veinless, ellipsoid, 3.2–4.2 × 1.1–1.3 mm, longer than wide; beak straight, pale green, 0.7–1 mm, ciliate-serrulate, apical teeth 0.2–0.4 mm. Stigmas 3. Achenes brown, obovoid to ellipsoid, obtusely trigonous in cross-section, 1.9–2.4 × 1–1.3 mm. 2n = 36.
Phenology: Fruiting mid May–mid Jul.
Habitat: Mainly calcareous soils on dry to mesic slopes, in partial shade in rich, deciduous or mixed deciduous-coniferous, open woods, bases of slopes, or full sun on exposed outcrops
Elevation: 10–2000 m
Alta., B.C., Man., N.B., N.S., Ont., Que., Sask., Alaska, Iowa, Maine, Mass., Mich., Minn., Nebr., N.H., N.Y., N.Dak., S.Dak., Vt., Wis., Wyo.
Hybrids between Carex peckii and other members of the section have not been confirmed; occasional plants appear to combine its characteristics with those of other species, such as C. tonsa.