Carex scirpoidea

Michx.

Bulrush Sedge

G5Secure Found in 19 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.1371852
Element CodePMCYP03PD0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderCyperales
FamilyCyperaceae
GenusCarex
Other Common Names
Carex faux-scirpe (FR) Northern Single-spike Sedge (EN) northern singlespike sedge (EN) Scirpus-like Sedge (EN) Single-spike Sedge (EN)
Concept Reference
Flora of North America Editorial Committee (FNA). 2002b. Flora of North America north of Mexico. Vol. 23. Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford Univ. Press, New York. xxiv + 608 pp.
Taxonomic Comments
This record is for a broad treatment of Carex scirpoidea, including C. scirpoidea ssp. pseudoscirpoidea (as well as subspecies convoluta and stenochlaena), as recognized by Dunlop in FNA (2002, vol. 23) and Kartesz (1999). Other treatments distinguish Carex pseudoscirpoidea as a distinct species (e.g., Ackerfield (2022), Kartesz (1994)). Carex curatorum is generally recognized as a distinct species.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-08-03
Change Date2025-08-13
Edition Date2025-08-13
Edition AuthorsSoteropoulos (2025)
Threat ImpactUnknown
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Carex scirpoidea is a wide-ranging perennial graminoid found in a variety of open habitat types, including fens, shorelines, prairie pavement barrens, dry ridge sites, fellfields, and alpine tundra, with four subspecies. It occurs in northern and western North America from Alaska, United States, and throughout Canada south to Maine west to New York, Michigan, Minnesota, North Dakota, New Mexico, Utah, and California in the United States, as well as Greenland, Europe, and Asia. There are over 1000 estimated occurrences, which face threats from development, grazing, peat mining, rights-of-way maintenance, logging, recreational activities, hydrological alteration, invasive species, and other threats in some places. Little is known about trends, but with a large range extent and large number of occurrences, abundant habitat, and broad habitat preferences, this species is considered secure.
Range Extent Comments
Carex scirpoidea occurs in northern and western North America from Alaska, United States, and throughout Canada south to Maine west to New York, Michigan, Minnesota, North Dakota, New Mexico, Utah, and California in the United States, as well as Greenland, Europe, and Asia (FNA 2002). Range extent was estimated to be over 20 million square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025 (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025). See individual entries for distribution details about the four subspecies.
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are over 1000 occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, this species is threatened by development, grazing, peat mining, rights-of-way maintenance, logging, recreational activities (especially off-road vehicles), hydrological alteration, invasive species, and other threats in some places, though there is insufficient data, including anecdotal accounts, to understand scope and severity of threats for this species (NatureServe 2025). However, their overall impact is likely negligible given the species' broad range, large number of occurrences, and affinity for typically abundant habitats.
Ecology & Habitat

Description

From CNHP Wetland Guide 2012: Growth Habit: culms arising singly or few together from stout, woody, branching, creeping rhizomes. Culms: stiff, triangular, purplish red at the base, 1-4 dm tall, exceeding the leaves.
Leaves: 2-4, clustered near the base. Blades: mostly flat, firm, 1-4 mm wide. Sheaths: tight, slightly filamentose, hyaline and puberulent ventrally, concave at mouth.
Bracts: none or inconspicous
Spikes: usually solitary, erect, plants dioecious, pistillate and staminate spikes similar in size, shape, and color. Terminal spike is cylindric, 1.5-4 cm long, 3-6 mm thick, densely flowered. Lateral spikes sometimes 1-2 at the base of the main spike on pistillate plants, small, sessile, perigynia erect-appressed.
Pistillate Scales: obovate-oblong with an obtuse to broadly acute tip, deep brown to black with a pale midrib and hyaline margins, puberulent and fringed-ciliate along the upper margins, shorter to longer and wider than the perigynia.
Perigynia: ovoid or oblong-obovoid, tapering to the bae, rounded tapering at the apex, short-hairy, especially the upper half, reddish purplish brown, lighter toward the base, 2-3.5 mm long, 1-1.7 mm wide. Nerves: obscure. Beaks: slender, terete, 0.25 mm long, tip somewhat hyaline-erose or identulate. Stigmas: 3

Diagnostic Characteristics

From CNHP Wetland Guide 2012: Main Characteristics:
Single spike
Perigynia reddish brown with white hairs
Pistillate scales red to purple, margins hyaline, central midrib extending midway or to scale apex
Achenes tightly enveloped by perigynia
Plants either cespitose or with long rhizomes

Habitat

Carex scirpoidea grows in fens, shorelines, prairie pavement barrens, dry ridge sites, fellfields with gravelly soils and noncalcaerous soils, weakly acidic, and calcaerous soils (FNA 2002, NatureServe 2025).
Terrestrial Habitats
Grassland/herbaceousAlpineBarrensBare rock/talus/scree
Palustrine Habitats
Bog/fenRiparian
Other Nations (2)
CanadaN5
ProvinceRankNative
AlbertaS5Yes
QuebecSNRYes
British ColumbiaS5Yes
Northwest TerritoriesS5Yes
OntarioS4Yes
ManitobaS4Yes
LabradorS4Yes
SaskatchewanS4Yes
New BrunswickS1Yes
Island of NewfoundlandS4Yes
NunavutS5Yes
Yukon TerritoryS5Yes
Nova ScotiaS2Yes
United StatesN5
ProvinceRankNative
North DakotaS2Yes
AlaskaSNRYes
MinnesotaS3Yes
OregonSNRYes
ColoradoSNRYes
MaineS2Yes
VermontS2Yes
WashingtonS5Yes
WyomingS4Yes
New YorkS1Yes
MichiganS2Yes
New HampshireSNRYes
CaliforniaSNRYes
NevadaS2Yes
MontanaS5Yes
IdahoSNRYes
UtahS4Yes
Threat Assessments

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (19)
Alaska (1)
AreaForestAcres
North KupreanofTongass National Forest114,660
Nevada (3)
AreaForestAcres
Humboldt - Angel LkHumboldt-Toiyabe National Forest1,008
Ruby - Lamoille CynHumboldt-Toiyabe National Forest32,771
Ruby - ThompsonHumboldt-Toiyabe National Forest5,289
New Hampshire (3)
AreaForestAcres
Great Gulf Ext.White Mountain National Forest15,110
Kinsman MountainWhite Mountain National Forest8,999
Presidential - Dry River ExtWhite Mountain National Forest10,555
Oregon (2)
AreaForestAcres
French Pete (a)Willamette National Forest1,668
Hurricane CreekWallowa-Whitman National Forest1,606
Utah (1)
AreaForestAcres
Horse Mountain - Mans PeakManti-Lasal National Forest22,159
Washington (5)
AreaForestAcres
Liberty BellOkanogan National Forest108,495
Long SwampOkanogan National Forest66,344
Mt. Baker WestMt Baker-Snoqualmie National Forest25,390
Salmo - Priest BColville National Forest11,869
TiffanyOkanogan National Forest22,045
Wyoming (4)
AreaForestAcres
Beartooth Proposed WildernessShoshone National Forest16,837
Cloud Peak ContiguousBighorn National Forest113,757
Snowy RangeMedicine Bow-Routt National Forest29,660
South Beartooth HighwayShoshone National Forest105,570
References (9)
  1. Ackerfield, J. 2022. Flora of Colorado. Second Edition. Bot. Misc. 60. BRIT Press, Fort Worth Botanic Garden/Botanical Research Institute of Texas, U.S.A. 861 pp.
  2. Flora of North America Editorial Committee (FNA). 2002b. Flora of North America north of Mexico. Vol. 23. Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford Univ. Press, New York. xxiv + 608 pp.
  3. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  4. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  5. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  6. Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
  7. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  8. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  9. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).