Herbs perennial, rhizomatous.
Culms solitary or clustered, trigonous or terete.
Leaves basal and cauline; cauline leaves sometimes consisting of bladeless sheaths; ligules present; blades to 25 cm × 2.5–4 mm.
Inflorescences terminal, spikes 1–10(30); involucral bracts 1–several, scale-like or blade-bearing and leaf-like throughout.
Spikes floral scales (10)20–200, spirally arranged, each subtending a flower or the proximal few empty.
Flowers bisexual; perianth persistent, of (8)10–25 hair-like, smooth bristles, greatly elongate, essentially straight, usually obscuring most of scales in spike, much longer than achene; stamens 1–3; styles deciduous, stigmas 3.
Achenes trigonous.
Mostly in cool temperate, alpine, and arctic regions of the northern hemisphere. Approximately 25 species; 3 species treated in Flora.
as described under Eriophorum
Herbs, perennial, cespitose or not, rhizomatous. Culms solitary or not, trigonous or terete. Leaves basal and cauline; cauline leaves sometimes bladeless sheaths; ligules present; blades filiform to flat with filiform tip, to 25 cm × 2.5-4 mm. Inflorescences terminal, spikelets solitary, erect or (1-)2-10(-30) in subcapitate or subumbellate panicle; involucral bracts 1-several, scalelike or blade-bearing and leaflike throughout. Spikelets: scales (10-)20-200, spirally arranged, each subtending flower, or proximal empty. Flowers bisexual; perianth persistent, of (8-)10-25 hairlike, smooth bristles, or very rarely 6 antrorsely barbed bristles, greatly elongate, essentially straight, usually obscuring most of scales in spikelet, much longer than achene; stamens 1-3; styles deciduous, linear, 3-fid. Achenes trigonous.In some species the North American populations are considered to be conspecific with Eurasian populations; differences in achene micromorphology and isozyme data suggest that these relationships should be investigated more thoroughly.