Spikes:

A single spike at the top of the stem, with staminate (male) flowers at the tip and pistillate (female) flowers below (androgynous), all crowded together. Pistillate flowers are initially erect, becoming spreading then reflexed (pointing down) in fruit. A bract at the base of the spike is absent.

Leaves and stems:

1 to 3 leaves are alternately attached to the stem near the base, each up to 5 inches long, up to 1.6 mm wide, about as wide as and shorter than the flowering stems. Bases are wrapped in a brown sheath that is not fibrous; old dried leaves may persist to the next season. Stems are erect to ascending, 3-sided, very slender, hairless and mostly smooth, elongating up to 16 inches at maturity and remain longer than the leaves. Plants form loose colonies from slender rhizomes, sometimes loose clumps of a few stems.

Fruit:

Fruit develops in late spring to mid-summer, the spike forming a cluster of seeds (achenes), each wrapped in a casing (perigynium), subtended by a scale. The scales of both staminate and pistillate flowers fall off as fruit develops. Each spike contains 2 to 6 fruits, overlapping and reflexed at maturity.

Pistillate scales are lance-oblong with a blunt or pointed tip, whitish to pale brown, awnless, wider than and about 2/3 or so as long as the perigynia. Perigynia are 5 to 8 mm long, .7 to 1.1 mm wide, faintly several-veined, light green turning yellowish to brown when mature, nearly round in cross-section, narrowly lance-oblong, spongy at the base, with a long taper to a pointed beak that lacks teeth at the tip. Achenes are 2 to 2.4 mm long, .8 to 1.1 mm wide, oval-oblong, weakly 3-sided, with a persistent style that extends about 1 mm past the tip of the perigynia beak.

Notes:

Carex pauciflora is an occasional sedge of bogs, swamps, peatlands, and floating mats in northern Minnesota. Where we encountered it in a shaded sphagnum bog, it was on the top of mossy hummocks, the stem bases buried deep in the moss.

Carex is a large genus, with over 600 species in North America and 150+ in Minnesota alone. They are grouped into sections, the species in each group having common traits. Carex pauciflora is the lone member of the Leucoglochin section in Minnesota; some of the section's common traits are: clump forming or rhizomatous, basal sheaths brown and not fibrous, leaves V-shaped in cross-section when young, 1 spike per stem, spike with staminate flowers at the tip (androgynous), perigynia elongated, hairless, weakly veined and nearly round in cross-section, achenes 3-sided with a persistent style.

Carex pauciflora should not be confused with any other sedge in Minnesota; the single, androgynous spike with few elongated, slender perigynia that become spreading then reflexed in fruit, plus the colony-forming growth primarily in mossy habitats, distinguish it from all other sedges.