Search Field Guide
Advanced Search
MT Gov Logo
Montana Field Guide

Montana Field Guides

Green-keeled Cottonsedge - Eriophorum viridicarinatum

Native Species

Global Rank: G5
State Rank: S4
(see State Rank Reason below)
C-value: 10


Agency Status
USFWS:
USFS:
BLM:


 





State Rank Reason (see State Rank above)
DRAFT: Requesting feedback on the 2026 revised rank, factors, and State Rank Reason outlined below and in the Conservation Status Rank Report. Eriophorum viridicarinatum is an uncommon species of fens across portions of western and central Montana, being most abundant in the northwestern portion of the state. Occurrences are almost entirely on publicly managed lands, including many on National Forest lands managed for multiple use. More than 2 dozen occurrences are protected within Glacier National Park or within designated wilderness or other conservation areas. Population levels appear to be relatively robust based on the available though limited data. Trends are unknown though populations have likely been relatively stable in the recent past or experienced only minor declines. Climate change may negatively affect this species over the next several decades. However, the timing and magnitude of potential impacts are largely unknown. Although climate change is listed as a potential threat to the species, it does not affect the overall threat rank or scoring, or the final subnational rank. Survey and monitoring data are needed to be able to more precisely determine population levels, assess condition and for assessing population trends.
Green-keeled Cottonsedge (Eriophorum viridicarinatum) Conservation Status Summary
State Rank: S4
Review Date = 07/08/2026
See the complete Conservation Status Rank Report
How we calculate Conservation Status Ranks
 
General Description
Rhizomatous. Stems 25–60 cm. Leaves: flat; blades 2–5 mm wide. Inflorescence 2 to 10 nodding, pedunculate spikelets; bracts 2 or more, leaf-like, as long as the inflorescence. Spikelets 15–30 mm long in fruit; lowest scale ca. as long as the spikelet. Fertile scales 4–6 mm long, greenish black with a pale midvein that reaches the tip. Bristles whitish. Achene 2–4 mm long, minutely apiculate (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Species Range
Montana Range Range Descriptions

Native
 


Range Comments
AK to NL south to BC, ID, CO, IL and PA (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Observations in Montana Natural Heritage Program Database
Number of Observations: 193

(Click on the following maps and charts to see full sized version) Map Help and Descriptions
Relative Density

Recency

 

(Observations spanning multiple months or years are excluded from time charts)



Habitat
Wet, organic soil of (often calcareous) fens in the valleys and montane zone.


References
  • Literature Cited AboveLegend:   View Online Publication
    • Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
  • Additional ReferencesLegend:   View Online Publication
    Do you know of a citation we're missing?
    • Lesica, P. 1986. Vegetation and flora of Pine Butte fen, Teton County, Montana. The Great Basin Naturalist 46(1): 22-32.
    • Lesica, P. 1994. The distribution of plant community diversity associated with glacial wetlands in the Ovando Valley, Montana. [Unpublished report.] The Nature Conservancy, Montana Field Office, Helena. 26 pp.
    • Lesica, P., M.T. Lavin, and P.F. Stickney. 2022. Manual of Montana Vascular Plants, Second Edition. Fort Worth, TX: BRIT Press. viii + 779 p.
    • Maguire, B. 1939. Distrubution notes concerning plants of Glacier National Park, Montana-II. Rhodora 41:504-508.
    • Moseley, R. K., R. J. Bursik, and M. Manusco. 1991. Floristic inventory of wetlands in Fremont and Teton counties, Idaho. Unpublished report on file IDCDC Department of Fish & Game, Boise, ID. 60 pp.
  • Web Search Engines for Articles on "Green-keeled Cottonsedge"
Login Logout
Citation for data on this website:
Green-keeled Cottonsedge — Eriophorum viridicarinatum.  Montana Field Guide.  .  Retrieved on , from