Carex sect. Squarrosae
Carices North. U.S., 564. 1847.
Plants cespitose or colonial, short to long rhizomatous. Culms brown or red-brown at base. Leaves: basal sheaths not fibrous; sheath fronts membranous; blades septate-nodulose, usually V-shaped in cross section when young, usually glabrous. Inflorescences single spike or racemose, with 2–9 spikes; proximal bracts leaflike or threadlike, sheathless or sheath longer than diameter of stem, at least 3 times as long as inflorescence; lateral spikes pistillate or infrequently gynecandrous, larger spikes usually with more than 50 perigynia, pedunculate, prophyllate; terminal spike staminate or gyncecandrous. Proximal pistillate scales sometimes with narrow, indistinct body, apex obtuse to awned. Perigynia ascending to spreading, many-veined, sessile or shortly stipitate, inflated, obconic, round in cross section, not more than 10 mm, base tapering or rounded-tapering, apex truncate, abruptly beaked, glabrous; beak 1.2–3.8, bidentate, teeth 0.3 mm or longer. Stigmas 3. Achenes trigonous, 1.2–3 mm, smaller than bodies of perigynia; style persistent or deciduous.
Temperate regions of e and mid w North America and temperate South America.
Species 4 (4 in the flora).
|1||Terminal spike largely staminate; pistillate scales with long awns, exceeding perigynia bodies; achenes 1.2–2.1 mm.||> 2|
|1||Terminal spike gynecandrous; pistillate scales with short awns or awnless, completely hidden by perigynia; achenes 2–3 mm.||> 3|
|2||Pistillate scales with narrow, indistinct body, 0.1–0.4 mm wide; staminate scales linear, 0.3–0.8 mm wide, loosely, irregularly imbricated with tips spreading; plants cespitose, not colonial, short-rhizomatous.||Carex frankii|
|2||Pistillate scales with wider, translucent body, 0.4–0.9(–1.1) mm wide; staminate scales lanceolate, narrowly ovate, or oblong-obovate, 0.9–1.6 mm wide, ± tightly imbricate in spike; plants not cespitose, colonial, long-rhizomatous.||Carex aureolensis|
|3||Style persistent, sinuous; achenes 1.9–2.5 times as long as wide; spikes 1–2(–3) per stem; pistillate portion of spike ovate to oblong; perigynia widely radiating, the proximal reflexed; beak usually smooth.||Carex squarrosa|
|3||Style deciduous, straight; achenes 1.2–1.9 times as long as wide; spikes (1–)2–4(–6) per stem; pistillate portion of spike oblong to elliptic; perigynia, including the proximal, appressed-ascending; beak often sparingly scabrous.||Carex typhina|