Carex crawei

Dewey

Crawe's Sedge

G5Secure Found in 1 roadless area NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.151967
Element CodePMCYP03360
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 de Crawe (FR) Crawe's 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 Date2025-07-08
Change Date1986-04-08
Edition Date2025-07-08
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 crawei is a wide-ranging perennial graminoid in open, often calcareous and at least seasonally wet, habitats. It occurs across much of North America from Newfoundland Island and New Brunswick, Canada west to British Columbia and south in the United States to New York and Connecticut, the Great Lakes region south to Georgia and west to Oklahoma, Colorado, Utah, Arizona, and Washington. There are over 450 estimated occurrences, which face threats from development, conversion to agriculture or pasture, grazing and trampling by cattle, haying, quarrying, rights-of-way maintenance, recreational activities, hydrological alteration, fire suppression leading to succession, and invasive species. 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 crawei occurs across much of North America from Newfoundland Island and New Brunswick, Canada west to British Columbia and south in the United States to New York and Connecticut, the Great Lakes region south to Georgia west to Oklahoma, Colorado, Utah, Arizona, and Washington (FNA 2002). Range extent was estimated to be approximately 7.5 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 450 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, conversion to agriculture or pasture, grazing and trampling by cattle, haying, quarrying, rights-of-way maintenance, recreational activities (especially off-road-vehicles), hydrological alteration, fire suppression leading to succession, 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 and large number of occurrences.
Ecology & Habitat

Description

Craw's Sedge is a perennial grass-like plant with a single or several stems, 1-3 dm high, which arise together from creeping rhizomes. The flat leaves, 1-3 mm wide, are mainly clustered near the base of the plant. 15-50 female flowers are clustered in cylindrical spikes, 1-2 cm long, and borne singly on stalks arising from the upper leaves (bracts). Male flowers are clustered together in the uppermost spike. Scales subtending the individual female flowers (perigynia) are shorter and narrower than the perigynia and are brown and membranous with a pale, thickened midvein. Elliptic, glabrous perigynia are pale green to light brown, often with reddish speckles, and 2-4 mm long. There are 3 stigmas, and the seed is triangular in cross-section.

From CNHP Wetland Guide 2012: Habit: culms arising singly or few together from well developed, creeping rhizomes. Culms: slender but stiff, 0.8-3(4) dm tall, exceeding the leaves, slightly phyllopodic. Leaves: 6-12. Blades: stiff, thick, flat, usually recurved-spreading, roughened on the margins towards the apex, 1.5-3 mm wide. Sheaths: tight, hyaline ventrally, occasionally brown-dotted toward the mouth. Bracts: lowest leaflike with well-developed sheath, shorter than inflorescence. Spikes: 3-5, narrowly oblong to cylindric, short- to long pedunculate, green to brown. Terminal: Staminate, pedunculate, 1-3 cm long, 2-3 mm wide. Lateral: Pistillate or androgynous, 1-3 cm long, 5-6 mm wide, closely flowered, widely separate, the lowest often nearly basal; perigynia 10-45, ascending. Pistillate Scales: broadly ovate with midrib often excurrent, equaling or narrower and shorter than the perigynia, reddish brown with hyaline margins and green center. Perigynia: ovoid or oblong-ovoid, rounded at sessile base, abruptly contracted at apex, somewhat terete, 2-3.5 mm long, 1.25-2 mm wide. Nerves: obscure to coarse on both faces, numerous. Beaks: straight, entire or minutely bidentulate, 0.4 mm long. Stigmas: 3

Diagnostic Characteristics

From CNHP Wetland Guide 2012: Main Characteristics:
Perigynia elliptic, light green to tan, often with reddish speckles
Rhizomatous, the shoots single
Terminal spike staminate, pedunculate
Widely spaced spikes
Pistillate scales broadly ovate with midrib often excurrent, equaling or shorter than perigynia, reddish brown with hyaline margins and green center
Styles 3

Habitat

Carex crawei grows in "dry to usually moist, open ground, often associated with calcareous gravels or limestone pavements, in wet meadows, fens, prairie swales, beach pools, shores and glades, less commonly edges of white-cedar thickets, prairie patches along rights-of-way, streams, ditches, and quarries" (FNA 2002).
Terrestrial Habitats
Forest EdgeGrassland/herbaceousBarrens
Palustrine Habitats
TEMPORARY POOLHERBACEOUS WETLANDBog/fenRiparian
Other Nations (2)
United StatesN4
ProvinceRankNative
OhioS3Yes
OklahomaSHYes
ArizonaSNRYes
MississippiS1Yes
South DakotaSNRYes
WyomingS1Yes
MontanaS2Yes
MinnesotaSNRYes
New YorkS2Yes
IowaS3Yes
MichiganSNRYes
ArkansasS3Yes
MissouriSNRYes
IdahoS1Yes
VirginiaS2Yes
TennesseeS3Yes
KansasS1Yes
GeorgiaS3Yes
IndianaS2Yes
WisconsinS4Yes
UtahS1Yes
NebraskaSNRYes
North DakotaSNRYes
KentuckyS3Yes
IllinoisS2Yes
WashingtonSNRYes
MaineSXYes
ConnecticutS1Yes
New JerseySHYes
ColoradoS1Yes
AlabamaSNRYes
CanadaN4
ProvinceRankNative
SaskatchewanS3Yes
British ColumbiaS3Yes
AlbertaS3Yes
ManitobaS3Yes
QuebecS3Yes
OntarioS4Yes
Island of NewfoundlandS1Yes
New BrunswickS2Yes
Threat Assessments

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (1)
Missouri (1)
AreaForestAcres
Swan Creek Rare II Study AreaMark Twain National Forest7,310
References (10)
  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. Heidel, B. L. 1994. Survey for PSORALEA HYPOGAEA in the Great Falls Resource Area, Lewistown District. Unpublished report to the Bureau of Land Management, Montana. Montana Natural Heritage Program, Helena, Montana. 22 pp. plus appendices.
  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. Lesica, P. 1991d. The rare vascular plants of Pine Butte Preserve. Unpublished report to The Nature Conservancy, Montana Field Office, Helena. 15 pp.
  7. Lesica, P. and J. S. Shelly. 1988b. The vegetation and flora of glaciated prairie potholes on the Blackfeet Indian Reservation, Montana: Progress report. Unpublished report to the Montana Nature Conservancy, Helena, MT. 19 pp.
  8. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  9. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  10. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).