Home/Species/ Big-head Sedge

Carex macrocephala

Willd. ex Spreng.

Big-head Sedge

G5Secure Found in 8 roadless areas NatureServe Explorer →

G5SecureGlobal Rank

Identity

Unique IDELEMENT_GLOBAL.2.128115

Element CodePMCYP03810

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 à grosses têtes (FR) Large-head Sedge (EN) largehead 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.

Taxonomic Comments

Kartesz recognized two varieties in Carex macrocephala, C. m. var. bracteata and C. m. var. macrocephala. These varieties are not recognized by the Flora of North America (2002).

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2023-03-08

Change Date1992-12-22

Edition Date2023-03-08

Edition AuthorsEberly (2023)

Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)

Number of Occurrences> 300

Rank Reasons

Carex macrocephala is a rhizomatous sedge of sandy coastal habitats with a wide distribution including the Pacific Coast of the United States in Alaska, Oregon, and Washington, Canada in British Columbia, Japan, the Russian Far East (Kamchatka), and Northern China. There are over 300 occurrences known. With a large range extent, over 300 occurrences, and no obvious intrinsic vulnerabilities, this species is considered secure.

Range Extent Comments

Carex macrocephala has a amphiberingian distribution including the Pacific Coast of the United States in Alaska, Oregon, and Washington, Canada in British Columbia, Japan, and the Russian Far East (Kamchatka). Reports from China are likely Carex kobomugi (syn. Carex macrocephala var. kobomugi) and based on confusion by its inclusion in C. macrocephala in older treatments (Wu et al. 2010). There are exotic locations in the eastern United States including New Jersey (Wootton 2007).

Occurrences Comments

By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1992 and 2023, it is estimated that there are at least 330 occurrences rangewide (GBIF 2023, SEINet 2023).

Threat Impact Comments

Although threats are not widely documented, this species is potentially threatened by sea level rise. However, as an early successional species it can colonize favorable habitats leaving potential for it to shift with sea level rise.

Ecology & Habitat

Habitat

This species is found on sandy or sometimes gravelly substrates in coastal areas including beaches, sounds, bays, and inlets, but especially on dunes (FNA 2002, Page et al. 2011).

Ecology

This early successional species grows in stressed and unstable conditions where it tolerates salt spray, shifting sands, and wave and wind disturbance and drought (B.C. CDC 2012, Page et al. 2011).

Reproduction

It can establish and spread quickly through rhizomatous root growth after disturbance (B.C. CDC 2012, Page et al. 2011).

Terrestrial Habitats

Sand/dune

Other Nations (2)

CanadaN4

Province	Rank	Native
British Columbia	S4	Yes

United StatesN4

Province	Rank	Native
Washington	SNR	Yes
Alaska	SNR	Yes
New Jersey	SNA	No
Oregon	S2	Yes

Threat Assessments

Threat	Scope	Severity	Timing
11 - Climate change & severe weather	Large (31-70%)	Unknown	High (continuing)
11.1 - Habitat shifting & alteration	Large (31-70%)	Unknown	High (continuing)

Plant Characteristics

DurationPERENNIAL

Economic Value (Genus)No

Roadless Areas (8)

Alaska (8)

Area	Forest	Acres
Chichagof	Tongass National Forest	555,858
Copper River Wetlands	Chugach National Forest	85,972
Fidalgo-Gravina	Chugach National Forest	257,968
Middle Kruzof	Tongass National Forest	14,724
North Kruzof	Tongass National Forest	33,146
South Kruzof	Tongass National Forest	55,193
Upper Situk	Tongass National Forest	16,789
Yakutat Forelands	Tongass National Forest	323,648

References (8)

B.C. Conservation Data Centre (B.C. CDC). 2012. Ecological Community Summary: <i>Carex macrocephala</i> Herbaceous Vegetation. B.C. Minist. of Environment. Online. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Mar 8, 2023).
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.
Global Biodiversity Information Facility (GBIF). 2023. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2023).
iNaturalist. 2023. Online. Available: https://www.inaturalist.org (accessed 2023).
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.
Page, N., P. Lilley, I.J. Walker, and R.G. Vennesland. 2011. Status report on coastal sand ecosystems in British Columbia. Report prepared for the coastal sand ecosystems Recovery team. vii + 83 pp.
Wootton, L. 2007. First Report of <i>Carex macrocephala</i> in Eastern North America with Notes on Its Co-Occurrence with Carex Kobomugi in New Jersey. The Journal of the Torrey Botanical Society 134(1)126-134.
Wu, Z. Y., P. H. Raven & D. Y. Hong, eds. 2010. Flora of China. Volume 23 (Acoraceae through Cyperaceae). Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis.

Carex macrocephala

Habitat

Ecology

Reproduction

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