Spikes:

Separate staminate (male) and pistillate (female) spikes, with 1 to 4 spikes up to ¾ inch long crowded at the tip of the stem, the terminal spikes usually all staminate, occasionally with a few female flowers at the base (androgynous). Below the staminate spikes are 4 or 5 slender-stalked pistillate spikes, widely spaced and arising singly from the nodes with a leaf-like bract at the base of the stalk. The stalk of the lowest spike is rather longer than the spike with the stalks becoming progressively shorter as they ascend the stem, the stalks initially erect to ascending, becoming drooping with maturity. Pistillate spikes are cylindrical, up to about 1¼ inches long, green at flowering time with white, thread-like styles. Staminate spikes are showier with large, creamy yellow stamens.

Leaves and stems:

Leaves are basal and alternate, mostly near the base, 2.5 to 4 mm wide, erect to ascending at flowering time, mostly shorter than the flowering stems, elongating up to 30 inches at maturity and becoming arching. Stem leaf sheaths are U-shaped and translucent whitish-green. The ligule (membrane where the leaf joins the sheath) is wider than long. Leaves are M-shaped in cross-section when young, and hairless though rough along the edges. Leaf color is dark green in shady habitats and brighter yellowish green in sunnier locations.

The brown remnants of the previous year's leaves sheath the base, the sheaths splitting into thread-like fibers (a characteristic known as “fibrillose”) and the fibers extending down to the roots. Stems are slender, 3-sided and mostly smooth except rough in the upper plant. Stems are initially erect to ascending, becoming leaning to nearly prostrate, elongating up to 3 feet at maturity and mostly longer than the leaves. Not all plants produce flowering stems. Plants form loose to dense clumps and create colonies from short rhizomes.

Fruit:

Fruit develops in mid to late spring, the pistillate spikes forming clusters of seeds (achenes), each wrapped in a casing (perigynium), subtended by a scale. The scales of staminate spikes are oblong-elliptic with a rounded tip, tan tinged darker brown towards the tip. The empty staminate scales persist after fruit has dropped off. Pistillate spikes each contain 10 to 40 fruits that are not crowded on the stalk.

Pistillate scales are lance to egg-shaped with a long taper to a pointed tip, light brown with a narrow band of darker brown along the midrib, and are shorter than the perigynia. Perigynia are 4.5 to 6.5 mm long, 1.2 to 2 mm wide, 2-ribbed (more obvious when dry), hairless, shiny, golden-greenish when mature, the body nearly spherical and abruptly tapering to a slender beak about as long as the body and slightly angled off to one side, with 2 teeth at the tip. Achenes are 2 to 2.5 mm long, up to 1.8 mm wide, 3-sided to nearly round in cross-section, somewhat irregular in shape, and mature to dark brown.

Notes:

A common woodland sedge, Carex sprengelii is found throughout Minnesota. It is a cool-season sedge, blooming in early spring and may bloom again in fall.

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 sprengelii is in the Hymenochlaenae section; some of its common traits are: typically clump forming and forming loose colonies, leaves M-shaped in cross-section when young, spikes long and cylindric and drooping on slender stalks, terminal spike either all staminate or with a few perigynia (usually at the tip, occasionally the base), perigynia round in cross-section, 2-veined, beaked, the beak usually toothed, 3-sided achenes, often growing in woodlands.

C. sprengelii is distinguished from all other Minnesota sedges by the nearly spherical perigynia body and long, slender beak, combined with the brown, fibrous base which is present on vegetative shoots as well as flowering plants.