Small clumps; rhizome short. Stems 25-75 cm × 0.75-1.5 mm, wiry, dull green or reddish, pith interrupted in a regular pattern by very small cavities. Inflorescence of 2 clusters, one pressed against stem, one on a slender branch. Stamens 3-4. Capsule 2.5-3 mm long, often > tepals.