Poir. in J.B.A.M.de Lamarck, Encycl. , Suppl. 3: 532 (1813)
Perennials 35–90 cm tall, loosely caespitose, subglabrous; rhizome long, creeping to ascending; stolons present; plant base often purplish. Stem thick, c. 2–3 mm in diam. Basal leaves usually 18–30 cm long, 13–19 mm wide, evenly narrowing; cauline leaves usually 4–5, up to 18 cm long and 13 mm wide. All leaves acute; margins papillose-serrulate; sheaths ±dissected, with mouth ciliate. Lower bract 2–3 cm long, herbaceous, shorter than inflorescence. Inflorescence decompound, ±dense, usually 1.5–8 × 2.5 × 6 cm; main branches with anthelas of 3–8-flowered clusters. Bracteoles ovate-lanceolate, 2.0–2.5 mm long, membranous-dirty white, sparsely ciliate. Tepals ±equal, glabrous, oblong-lanceolate, usually (3.0–) 3.5–4.2 mm long, dirty white (whitish-membranous with pale straw-brown base and 1–3 prominent veins). Stamens 6; anthers 1.1–1.3 mm long; filaments c. 1.0–1.1 mm long; style c. 1.0 mm long; stigmas 0.9–1.3 mm long. Capsule ±ovoid, acuminate, mucronate, pale brown; capsule segments c. 2.5 × 1.5–1.6 mm long, including mucro c. 0.5 mm long. Seeds ellipsoidal, 1.1–1.3 mm long, 0.6–0.7 mm wide; appendage c. 0.1 mm long, probably not or indistinctly fibrillate. 2n=12, fide L.Borgen, Check-List Chromos. Macarones. Vasc. Pl. 30 (1977).