Carex torta

Boott ex Tuckerman

Twisted Sedge

G5Secure Found in 12 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.152577
Element CodePMCYP03DU0
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 tordu (FR) Streambed Sedge (EN) twisted sedge (EN)
Concept Reference
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.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-08-20
Change Date1984-02-29
Edition Date2025-08-20
Edition AuthorsSoteropoulos (2025)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Carex torta is a wide-ranging perennial graminoid found in rocky streambeds. It occurs in eastern North America from Nova Scotia west to Ontario, Canada, and Iowa south to Georgia west to Mississippi, Arkansas, and Oklahoma in the United States. There are over 550 estimated occurrences, which potentially face threats from development, hydrological alteration, flooding and intense storms, invasive species, and other threats in some places. Little is known about trends, but with a large range extent and large number of occurrences, this species is considered secure.
Range Extent Comments
Carex torta occurs in eastern North America from Nova Scotia west to Ontario (presumed extirpated), Canada, and Iowa south to northern Georgia west to northwestern Mississippi, western Arkansas, and eastern Oklahoma in the United States (FNA 2002, Weakley and the Southeastern Flora Team 2025). Range extent was estimated to be approximately 2 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).
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 550 occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, this species is potentially threatened by development, hydrological alteration, flooding and intense storms, invasive species, and other threats in some places. However, their overall impact is likely negligible given the species' broad range, large number of occurrences, and no obvious intrinsic vulnerabilities.
Ecology & Habitat

Habitat

Carex torta grows in "rocky streambeds, often dominant in patches in the beds of mountain streams, along their banks, and on rocky or cobbly islands" (FNA 2002, Weakley and the Southeastern Flora Team 2025).
Palustrine Habitats
Riparian
Other Nations (2)
CanadaN5
ProvinceRankNative
OntarioSXYes
New BrunswickS5Yes
QuebecS3Yes
Nova ScotiaS5Yes
United StatesN5
ProvinceRankNative
DelawareS2Yes
New YorkS5Yes
West VirginiaS5Yes
ArkansasS4Yes
New HampshireSNRYes
District of ColumbiaSNRYes
IndianaS3Yes
Rhode IslandSNRYes
GeorgiaS1Yes
MaineSNRYes
PennsylvaniaS5Yes
South CarolinaS2Yes
MissouriSNRYes
ConnecticutSNRYes
MassachusettsSNRYes
New JerseyS4Yes
OklahomaSNRYes
OhioSNRYes
IowaSNRYes
MississippiS1Yes
TennesseeSNRYes
KentuckyS5Yes
VermontS5Yes
IllinoisS2Yes
MarylandSNRYes
VirginiaS4Yes
North CarolinaS3Yes
AlabamaSNRYes
Threat Assessments

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (12)
Georgia (1)
AreaForestAcres
Joe GapChattahoochee National Forest5,321
Maine (1)
AreaForestAcres
Caribou - Speckled ExtWhite Mountain National Forest5,988
New Hampshire (2)
AreaForestAcres
Great Gulf Ext.White Mountain National Forest15,110
Wild RiverWhite Mountain National Forest46,878
North Carolina (5)
AreaForestAcres
Barkers Creek (addition)Nantahala National Forest975
Harper CreekPisgah National Forest7,325
Lost CovePisgah National Forest5,944
SnowbirdNantahala National Forest8,489
Wilson CreekPisgah National Forest4,863
South Carolina (1)
AreaForestAcres
Ellicott Rock 2Sumter National Forest517
Virginia (2)
AreaForestAcres
Elliott KnobGeorge Washington National Forest9,380
JerkemtightGeorge Washington National Forest16,687
References (8)
  1. 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.
  2. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  3. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  4. 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.
  5. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  6. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  7. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).
  8. Weakley, A.S., and Southeastern Flora Team. 2025. Flora of the southeastern United States Web App. Edition of February 18, 2025. University of North Carolina Herbarium (NCU), North Carolina Botanical Garden, University of North Carolina, Chapel Hill. Online. Available: https://fsus.ncbg.unc.edu (accessed 2025).