Carex sect. Multiflorae
in H. G. A. Engler, Pflanzenr. 38[IV,20]: 142. 1909.
Plants loosely cespitose, sometimes long-rhizomatous. Culms brown at base, usually not more than 1 mm wide distally. Leaves: basal sheaths fibrous; sheath fronts membranous, often dotted red, transversely rugose; blades V-shaped in cross section when young, glabrous. Inflorescences usually paniculate, usually condensed, with 8–20+ spikes, usually more than 15 spikes; proximal bracts filiform, sheathless; spikes androgynous, rarely also with some staminate flowers proximally or pistillate, sessile, prophylls absent. Proximal pistillate scales yellow or brown, sometimes with hyaline margins and 3-veined center, apex obtuse, at least distally, to awned. Perigynia ascending or eventually spreading, veined abaxially, veined or veinless adaxially, stipitate, lanceolate to broadly ovate, plano-convex in cross section, base rounded or subcordate, with spongy tissue, margins acutely angled, apex tapering or abruptly contracted to beak, glabrous; beak bidentate, with abaxial suture. Stigmas 2. Achenes biconvex, smaller than bodies of perigynia; style deciduous.
Mainly North America, Mexico, introduced to Europe and New Zealand.
Species 7 (7 in the flora).
Carex sect. Multiflorae is not clearly distinguished from several other sections in the subgenus Vignea (i.e., sections Vulpinae, Foetidae, Bracteosae). Although sect. Multiflorae is generally distinguishable from sect. Vulpinae by the presence of spongy tissue lateral to the achene (rather than basal), the perigynia contracted to beak (rather than tapered), the conical style base (rather than cylindric), and the generally prominent setaceous bracts, some taxa within each section have that combination of characters.
|1||Sheaths not rugose; bracts scalelike; scales silvery.||> 2|
|1||Sheaths rugose; bracts setaceous; scales hyaline, usually short-awned.||> 3|
|2||Perigynia pale or dark brown, 5–11-veined adaxially, 3–3.6 × 1.2–1.6 mm; proximal bracts prolonged with 10–15 mm setaceous apex.||Carex chihuahuensis|
|2||Perigynia dark brown to black, 3–5-veined adaxially, 3–4.5 × 1.5–2 mm; proximal bracts prolonged with 15–50 mm setaceous apex.||Carex alma|
|3||Perigynia red dotted.||Carex triangularis|
|3||Perigynia lacking red dots.||> 4|
|4||Perigynia dull yellow-green to pale brown.||> 5|
|4||Perigynia golden brown or yellow-brown.||> 6|
|5||Leaves shorter than flowering stem; perigynia 3.2–4 × 2–2.6 mm, body of the widest orbicular; beak 1/3 length of body.||Carex fissa|
|5||Leaves longer than flowering stem; perigynia 2–3.2 × 1.3–1.8 mm, body of the widest ovate to orbicular; beak 1/3–1/2 length of body.||Carex vulpinoidea|
|6||Perigynia golden brown, conspicuously 3-veined abaxially, otherwise veinless, 2.2–3 mm.||Carex annectens|
|6||Perigynia dull yellow-brown to medium brown, usually veined on both faces, to 7-veined abaxially, 2.8–4 mm.||Carex densa|