Culms 20-100 cm. Inflorescences: larger involucral bracts 2-12 cm; peduncles 5-60 mm, glabrous or scabrous on angles. Scales brown to gray proximally, paler distally, usually with broad white membranous margins. 2n = 58.

Fruiting summer. Marshes, bogs, fens, meadows, shores; 0-3500 m; Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon; Alaska, Colo., Idaho, Ill., Ind., Iowa, Maine, Mich., Minn., Mont., Nebr., N.Mex., N.Y., N.Dak., Oreg., S.Dak., Utah, Wash., Wis., Wyo.; Eurasia.

Perennial herb with long-creeping rhizomes, colonial 20 cm - 1 m tall

Leaves: alternate, to 40 cm long, 1.5 - 8 mm wide, more or less flat with a three-angled tip, linear, channeled in cross-section, parallel-veined, with a sheathing base that encloses the stem. Sheaths tinged dark red at the top.

Inflorescence: a terminal cluster of two to ten spikelets, subtended by leaf-like bracts. Bracts one to three, blade-bearing, unequal, dark red at the base, 1 - 12 cm long, the longest equal to or surpassing the inflorescence.

Flowers: minute, subtended by a floral scale, lacking sepals and petals, bearing numerous hair-like bristles that form a dense, cottony tuft when the spikelet reaches maturity. Bristles persistent, white (sometimes yellowish), more or less straight, elongated, 1.5 - 3 cm long, much longer than the achene. Stamens three, exserted. Anthers 2 - 5 mm long. Pistil one. Style three-cleft.

Fruit: a one-seeded achene, black, 2 - 5 mm long, two to three times as long as wide, reverse lance-shaped, three-angled. Seed with a thin, non-adherent wall.

Culm: 20 cm - 1 m long, about 1 mm wide, nearly circular in cross-section, solid.

Spikelets: on 0.5 - 6 cm long stalks, 1 - 2 cm long in flower, 2 - 5 cm long in fruit, egg-shaped. Floral scales spirally arranged, brown to gray basally, paler towards the apex, often white-margined, 0.5 - 1 cm long, egg-shaped or lance-shaped with a more or less pointed apex, midrib prominent (fading near tip).

Similar species: The similar Eriophorum virginicum differs by having colored bristles (which do not elongate until August and September) and a single stamen. Eriophorum viridicarinatum is also similar but differs by lacking a reddish tinge on its leaf sheaths and inflorescence bracts.

Flowering: late April to mid-May

Habitat and ecology: Calcareous habitats and acid bogs.

Occurence in the Chicago region: native

Etymology: Eriophorum means "bearing cotton," from the Greek words erion (cotton or wool) and phoros (bearing). Angustifolium means narrow-leaved.

Author: The Morton Arboretum

Infrequent on the borders of sloughs and in marshes and bogs.