Author
Hieu Nguyen
Best recognition factors
Stems triangular, scales of spikelet with a long awn extending beyond
apex of scale. Spikelets 1–5(–10); perianth bristles very stout to slender, unequal or equal, equaling achene to rudimentary, retrorsely spinulose
Ecology
Fresh to brackish shores, marshes, lakes, fens, often emergent in water to 0.7 m; 0–2400 m;
Family
Cyperaceae
Flowers
Flowers: perianth members 4–8, sometimes fewer, brown, bristlelike,variably slender to stout, equal or unequal, all equaling achene bodyto all rudimentary, retrorsely spinulose; anthers 2–3 mm; styles 2–3-fid.
Fruit
Fruits achene brown, biconvex to compressed bluntly trigonous, obovoid to
obpyriform, (2–)2.5–3.5 × 1.3–2.3 mm; beak 0.1–0.5 mm. 2n = 74, 78
Habit and stem features
Herbs, annual
Culms sharply trigonous, sides convex to concave proximally,
deeply concave to flat distally, 0.1-2m x 1-6mm, smooth
Inflorescences
Inflorescences capitate; proximal bract usually erect, resembling leaf blade
but trigonous proximally, (1–)3–20 cm.
Leaves
Leaves basal, sheath fronts membranous distally, orifice adaxially truncate
to concave, often splitting; ligules 2-fid, 1 mm; blades 2–6, proximally
V-shaped, distally trigonous to asymmetrically laterally flattened in cross
section, angles often scabridulous distally; distal blade (1–)2–5 times as
long as sheath, 50–750 × 2–9 mm.
References
Flora of
Magnoliophyta: Commelinidae (in part): Cyperaceae.
Godfrey, R. K. and J. W. Wooten. 1979. Aquatic and Wetland Plants of the
Spikelets
Spikelets 1–5(–10), 5–23 × 3–5(–7) mm;
scales bright (to very dark) orange-, red-brown, or purplish brown to
straw-colored, often prominently lineolate-spotted, midrib mostly paler,
ovate, 3.5–6 × 2–3 mm, smooth or awn sparsely spinulose, margins deciduously
ciliolate, flanks ribless except sometimes proximal scales, midrib prominent,
apex acute (to obtuse), 2-fid, notch (0.3–)0.5–1 mm deep, awn mostly irregularly
bent, 0.5–1.5(–2.5) mm.
Synonyms
Scirpus pungens