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Section Griseae
See list of 6 species in this sectionBasal leaf sheath color is a critical character, and, therefore, complete specimens are necessary for confident identification (i.e., collections of only the upper stem and inflorescence may be difficult to assign to species). Color is best assessed with bright light and low magnification. Reference: Naczi and Bryson (2002).
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1a. Leaf sheaths, and sometimes the blades along the abaxial midrib, hispidulous; beak of perigynium (0.5–) 0.8–1.3 mm long
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1b. Leaf sheaths and blades glabrous; beak of perigynium 0–0.6 mm long (up to 1.2 mm long in C. oligocarpa)
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2a. Basal leaf sheaths of reproductive stems yellow-brown to dark brown, without anthocyanic pigments; carpellate spikes with (6–) 12–45 (–65) perigynia [Fig. 90]
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2b. Basal leaf sheaths of reproductive stems purple-red to dark purple (very rarely dark brown); carpellate spikes with 2–18 perigynia
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4a. Lowermost bract of inflorescence with a tightly clasping sheath; widest leaf blades (1.8–) 2.4–4 (–4.6) mm wide; carpellate spikes loosely flowered, many of the perigynia borne in 2 ranks; beak of perigynium 0.4–1.2 mm long
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4b. Lowermost bract of inflorescence with a loosely clasping sheath; widest leaf blades (3.7–) 4.2–8.2 (–9.1) mm wide; carpellate spikes densely flowered, the perigynia spirally arranged around the spike axis; beak of perigynium (0.2–) 0.3–0.6 mm long
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5a. Perigynia terete or nearly so in cross-section, (1.8–) 2–2.6 mm wide, 1.8–2.3 (–2.6) times as long as wide; achenes borne on a stipe (0.2–) 0.3–0.4 (–0.5) mm long
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5b. Perigynia obtusely trigonous in cross-section, 1.5–1.9 (–2.2) mm wide, (2.2–) 2.5–3.1 times as long as wide; achenes borne on a stipe (0.3–) 0.4–0.6 mm long
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Each photo represents one species in this section.