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Section Paludosae
See list of 7 species in this sectionReference: Reznicek and Catling (2002).
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1a. Perigynia glabrous; style persistent on the achene; leaf blades (2.6–) 5.5–21 mm wide
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2a. Perigynia 3–4.5 mm long, glaucous; perigynium beak 0.3–0.6 mm long, weakly bidentate, the apical teeth up to 0.2 mm
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2b. Perigynia 3.9–7.8 mm long, not glaucous; perigynium beak 0.5–1.6 mm long, terminated by 2 distinct teeth (0.1–) 0.2–0.7 (–0.9) mm long
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3a. Leaves with blades (5.5–) 8.5–21 mm wide, the longest ligules 13–40 mm long
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3b. Leaves with blades 2.6–5 (–6) mm wide, the longest ligules 1.8–12.5 mm long
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1b. Perigynia pubescent; style articulated with the summit of the achene and deciduous from it at maturity; leaf blades 0.7–8.5 mm wide
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4a. Beak of perigynium with soft, hyaline, obscure teeth; staminate spikes 1 or rarely 2, borne on peduncles 2–20 mm long, usually exceeding the height of the lowest bract of the inflorescence
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4b. Beak of perigynium with distinct, firm teeth 0.2–0.8 mm long; staminate spikes 1–3, borne on peduncles (8–) 20–90 mm long, usually equaled or overtopped by the lowest bract
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5a. Perigynia 4.5–6.5 mm long, the pubescence short and relatively sparse, not concealing the veins or cellular details of the perigynium body; plants of dry, sandy or rocky soil
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5b. Perigynia 2.4–5 (–5.2) mm long, the pubescence longer and dense, concealing the veins and cellular details of the perigynium body; plants of shorelines and wetlands
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6a. Leaf blades M-shaped in cross-section (at least when young), sometimes ± flat at maturity, (2–) 2.2–4.5 (–6) mm wide, not prolonged apically into an elongate, filiform tip, with a prominent midvein that forms a sharp, abaxial keel for much of the lengt
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6b. Leaf blades involute, 0.7–2 (–2.2) mm wide, prolonged at the apex into an elongate, sometimes curled, filiform tip, with a low, rounded midvein forming an inconspicuous abaxial keel
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Each photo represents one species in this section.