Eriophorum chamissonis C.A. Mey.
Chamisso's cotton-grass (Chamisso’s cotton-grass)
Cyperaceae (Sedge family)

Introduction to Vascular Plants


© Jamie Fenneman     (Photo ID #16993)


E-Flora BC Static Map

Distribution of Eriophorum chamissonis
Click here to view the full interactive map and legend

Species Information

Perennial herb from creeping rhizomes or stolons, extensively colonial; stem 20-75 cm tall.
Basal sheaths brown to purplish-brown, cross-wrinkled, persistent, not or only somewhat expanded upwards, the uppermost sheaths usually bladeless; stem leaves few, usually 1 to 3, located below the middle of the stems, mostly borne near the bases, rarely one above; blades 0.4-2 mm wide, short to elongate, thread-like, folded throughout or triangular in cross-section.
Spikes solitary, terminal, erect, at least some of them pendulous, appearing broad-based, egg-shaped-cylindrical and 1.5-2 cm long in flower, globe-shaped and 2-4 cm long in fruit; anthers mostly 1-3 (3.2) mm long; involucral bracts lacking.
Scales blackish to greyish, the middle scales lanceolate or broadly lanceolate, appressed to ascending, the midribs not reaching the tips, more or less long and sharp-pointed or blunt, with narrow, pale margins or broad translucent margins, the sterile sc
Two, sometimes difficult to separate, varieties occur in BC:

1. Perianth bristles rust-coloured; plants stout, the stems over 1.5 mm wide at the bases; middle scales lanceolate, more or less long-pointed, with narrow, pale margins...................... var. chamissonis.

1. Perianth bristles white to tawny; plants slender, the stems less than 1.5 mm wide at the bases; middle scales broadly lanceolate, blunt, with broad translucent margins..................... var. albidum (Nyl.) Fern.

SourceThe Illustrated Flora of British Columbia


Ecological Framework for Eriophorum chamissonis

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
998 15 2085
Slope Gradient (%)
2 0 50

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

57 24 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
6 1 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

AT(1), BAFA(3), BWBS(5), CDF(1), CWH(35), ESSF(24), ICH(20), IDF(2), MS(13), SBPS(3), SBS(43), SWB(3)

Habitat and Range

Bogs, streambanks, lakeshores and wet meadows in all vegetation zones; var. chamissonis – common throughout BC; var. albidum – infrequent in N BC, rare S to 51°N east of the Coast-Cascade Mountains; N to AK, YT and NT, E to NF and S to WI, MN, ND, CO and OR.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Eriophorum chamissonis var. aquatile (Norman) Fernald
Eriophorum russeolum Fr. ex Hartm.
Eriophorum russeolum subsp. rufescens (E.S. Anderson) Hyl., nom. inq.