Spikes:

Separate staminate (male) and pistillate (female) spikes, with 1 to 3 staminate spikes up to 2+ inches long at the top of the stem, which occasionally have a few pistillate flowers at the tip (gynecandrous). Below the staminate spikes are 2 to 6 slender-stalked pistillate spikes, arising singly from the nodes; occasionally the pistillate spikes have a few staminate flowers at the tip (androgynous). The stalk of the lowest spike is longest with both staminate and pistillate stalks becoming somewhat shorter as they ascend the stem, and drooping with maturity. Pistillate spikes are slender and cylindrical, up to 4¾ inches long, each with a leaf-like bract at the base of the stalk, the bract of the lowest spike over-topping the terminal spike. All spikes are fairly evenly spaced on the stem, except the lowest spike is typically a bit more widely separated from the one above it.

Leaves and stems:

Leaves are basal and alternate, up to 6 leaves per stem, 3.3 to 12 mm wide, up to 20 inches long, shorter than the flowering stem though the upper stem leaves can over-top the spikes. Stem leaf sheaths loosely wrap the stem and are papery, translucent whitish, U to V-shaped at the top. The ligule (membrane where the leaf joins the sheath) is longer than wide with a broad band of loose tissue around the edge. Leaves are M-shaped in cross-section when young, and hairless though slightly rough along the edges.

Bases are wrapped in a smooth, brown to reddish sheath that becomes somewhat fibrous with maturity. Stems are stout, 3-sided and slightly rough along the angles, erect to ascending, elongating up to 4 feet or more at maturity. Not all plants produce flowering stems. Plants form loose to dense clumps and may form loose colonies from creeping rhizomes.

Fruit:

Fruit develops in late spring through mid-summer, the pistillate spikes forming clusters of seeds (achenes), each wrapped in a casing (perigynium), subtended by a scale. The empty staminate scales persist after fruit has dropped off. Pistillate spikes are densely packed with numerous fruits, the perigynia ascending to widely spreading.

Pistillate scales are mostly lance-oblong, translucent white or tinged chestnut brown with a green midrib that extends to a long awn that has rough hairs along the edge, the tip of the scale body straight across or slightly heart-shaped, the body shorter than the perigynia but the awn much longer. Perigynia are light green tinged light brown at maturity, 1.8 to 3.7 mm long, 1.2 to 2.5 mm wide, 2-ribbed and essentially veinless, hairless, loosely wrapping the achene, oval-elliptic, widest at or above the middle, rounded on the tip end and abruptly tapering to a short, toothless beak that is slightly angled and off-center. Achenes are 1.5 to 1.7 mm long, lens-shaped and variously crimped on one side (occasionally both).

Notes:

Carex crinita reaches the western edge of its range in Minnesota, found in wet places primarily in the northeast quarter of the state.

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 crinita is in the Phacocystis section (a combination of former Acutae and Cryptocarpae sections); some of its common traits are: typically clump forming and rhizomatous, leaves V or M-shaped in cross-section when young and hairless except along the edges, spikes long and cylindric, spikes drooping on slender stalks to nearly stalkless, terminal spike usually all staminate or with a few perigynia at the tip, perigynia densely packed, green to brownish, 2-ribbed, weakly veined and short-beaked, achenes lens-shaped with 2 stigmas, growing in wetlands and other wet places.

Carex crinita is very similar in appearance to Carex gynandra, which has rough textured basal sheaths, periginia more tapering at the tip, and the body of pistillate scales taper or are slightly rounded at the tip, where C. crinita scales are straight across or have somewhat heart-shaped lobes at the top of the body, perigynia rounded at the tip, and basal sheaths that are smooth. There are 2 varieties: var. crinita is found throughout much of the eastern half of North America, including Minnesota, and described above; var. brevicrinis is more southern and eastern and lacks the crimp in the achene.