Description
Key Characters:
Growth Form:
Perennials, rhizomes brown, slender.
Stems:
Culms laxly tufted, slender, soft, terete (cylindrical), 9–60 cm tall, 0.5–1.5 mm in diameter.
Roots:
Leaves:
Leaves simple.
alternate, basal or nearly so
reduced to bladeless sheaths
Margins entire.
Sheathing; sheaths membranous, pale, streaked with reddish brown especially toward base, 2–9 cm long, the orifice truncate.
Stipules absent.
Flowers:
Flowers in spikelets many–flowered, lanceoloid to narrowly ovoid, 8–17 mm long, 2–4 mm wide, gradually narrowed to an acute apex; glumes pale and tinged reddish brown on both sides of midnerve, thin, membranous, lanceolate–elliptic 2–3 mm long, 1.2–1.3 mm wide, gradually narrowed to a subobtuse apex, midnerve yellowish green, ending below the glume apex.
Flowers bisexual (perfect).
Calyx of 1–4 bristles, slender, slightly longer than the achene, sometimes absent.
Corolla (petals) absent.
Ovary superior; styles base conical, spongy, ⅓–⅔ as wide as achene; stigmas 2.
Fruit:
Achenes dark yellow; smooth; narrowly obovate; lenticular; 1–1.5 mm long; 0.7–0.9 mm wide.
Seeds 1; seed coat thin; free from pericarp; embryo basal; endosperm abundant.
Ploidy:
2n = 18
Habitat:
Occurring along margins of marshes and ponds.
Elevation Range:
0–250 m.