Spikes:

A cluster ¾ to 1½ inches long at the top of the stem, made up of 8 to 12, round to short-cylindric, stalkless spikes, all tightly crowded or only slightly separated, though the lowest spike is occasionally more distant. Clusters may be branching (compound), with multiple spikes along 1 or 2 short branches at the base of the cluster, or unbranched (simple). All spikes are alike with staminate (male) flowers at the tip and pistillate (female) flowers at the base (androgynous). At the base of each spike/branch is a scale-like bract; the lowest bract usually has a conspicuous bristle-like tip that is often longer than the associated spike, sometimes slightly over-topping the terminal spike.

Leaves and stems:

Leaves are basal and alternate, mostly near the base, up to 7 mm wide, shorter than to longer than the flowering stems. Stem leaf sheaths are convex at the tip, smooth on the front, somewhat loosely wrap the stem, fragile and easily torn, translucent whitish and variably covered in reddish to purplish dots, especially along the edges and near the tip. The ligule (membrane where the leaf joins the sheath) is shorter or longer than wide, rounded to blunt at the tip. Leaves are hairless and V-shaped in cross-section when young.

Bases are wrapped in a brown sheath that persists to the next season and becomes fibrous. Stems are erect to ascending, strongly 3-sided with narrow wings, stout but spongy and easily compressed, rough textured at least on the upper stem, elongating up to about 30 inches at maturity. Plants are clump-forming and not colony-forming.

Fruit:

Fruit develops in late spring through early summer, the pistillate spikes forming clusters of seeds (achenes), each wrapped in a casing (perigynium), subtended by a scale. Pistillate spikes each contain 8 to 15 fruits that are ascending to spreading and crowded on the stalk.

Pistillate scales are narrowly egg-shaped, brown with translucent edging and a green midrib, often with a long taper to a pointed tip, and are somewhat shorter to about as long as the perigynia. Perigynia are 3 to 4 mm long, 1.5 to 1.8 mm wide (twice or more as long as wide), tan to golden brown at maturity except paler at the base, veinless or obscurely 3 to 5-veined on the front, hairless but with minute reddish-brown teeth along the edge on the upper half, not inflated but somewhat spongy at the base, flattened on the back side, narrowly egg-shaped in outline, widest near the base, the base rounded but abruptly tapered to a short stalk-like structure (stipe), the tip tapering to a toothed beak 1.5 to 2 mm long (about or nearly as long as the body). Achenes are about 1.5 mm long and wide, flattened lens-shaped, nearly round in outline, and mature to brown.

Notes:

Carex alopecoidea is an occasional sedge usually found in seasonally wet places. In Minnesota it is most often found in floodplain forests and on river and stream banks, but also in wet meadows, marsh edges, and ditches.

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 alopecoidea is in the Vulpinae section; some of its common traits are: clump forming, stems usually spongy, basal sheaths fibrous or not, sheath fronts cross-wrinkled (rugose) or not, leaves hairless and V-shaped in cross-section when young, spike clusters branched (compound) or not (simple) and often crowded, 4 to 20 stalkless spikes, terminal spike with staminate flowers at the tip (androgynous), lateral spikes androgynous or all pistillate, perigynia twice or more as long as wide, widest at/near the base, the base rounded with spongy tissue, tapered at the tip to a toothed beak, flattened lens-shaped achenes. Several of these traits are shared with the Phaestoglochin and Multiflorae sections; both have perigynia widest near the middle and usually less than twice as long as wide, firm stems and the former usually has more than 15 spikes.

Carex alopecoidea is distinguished by its stems that are stout but easily compressed and strongly 3-sided with narrow wings, fragile leaf sheaths that are smooth (not wrinkled) on the front, convex at the tip and variably red-dotted, androgynous spikes, perigynia 3 to 4 mm long that are widest at/near the base, rounded at the base and tapering to a toothed beak about or nearly as long as the perigynia body (measured from the tip of the achene on mature plants), and pistillate scales that are nearly as long as the perigynia and tapered to a pointed tip but not awned. Compare to species with a similar arrangement of spikes, which may have firm stems; leaf sheaths that are concave at the tip, wrinkled on the front, striped or mottled on the back, or not fragile; perigynia widest near the middle; or pistillate scales that may be awned or are much shorter than the perigynia.