Carex is a vast genus of more than 2,000 species of grassy plants
in the family Cyperaceae, commonly known as sedges (or seg, in older
books). Other members of the
Cyperaceae family are also called sedges,
however those of genus
Carex may be called "true" sedges, and it is
the most species-rich genus in the family. The study of
Carex is known
2 Ecology and distribution
3 Taxonomy and cytogenetics
6 External links
All species of
Carex are perennial, although some species, such as
C. bebbii and C. viridula can fruit in their first year of
growth, and may not survive longer. They typically have rhizomes,
stolons or short rootstocks, but some species grow in tufts
(caespitose). The culm – the flower-bearing stalk – is
unbranched and usually erect. It is usually distinctly triangular
The leaves of
Carex comprise a blade, which extends away from the
stalk, and a sheath, which encloses part of the stalk. The blade is
normally long and flat, but may be folded, inrolled, channelled or
absent. The leaves have parallel veins and a distinct midrib. Where
the blade meets the culm there is a structure called the ligule.
The colour of foliage may be green, red or brown, and "ranges from
fine and hair-like, sometimes with curled tips, to quite broad with a
noticeable midrib and sometimes razor sharp edges".
Carex panicea, the upper spike contains male flowers, and the
lower spike contains female flowers.
The flowers of
Carex are small and are combined into spikes, which are
themselves combined into a larger inflorescence. The spike typically
contains many flowers, but can hold as few as one in some species.
Carex species are monoecious; each flower is either male
(staminate) or female (pistillate). A few species are dioecious.
Sedges exhibit diverse arrangements of male and female flowers. Often,
the lower spikes are entirely pistillate and upper spikes staminate,
with one or more spikes in between having pistillate flowers near the
base and staminate flowers near the tip. In other species, all
spikes are similar. In that case, they may have male flowers above and
female flowers below (androgynous) or female flowers above and male
flowers below (gynecandrous). In relatively few species, the
arrangement of flowers is irregular.
The defining structure of the genus
Carex is the bottle-shaped bract
surrounding each female flower. This structure is called the
perigynium or utricle, a modified prophyll. It is typically extended
into a "rostrum" or beak, which is often divided at the tip (bifid)
into two teeth. The shape, venation, and vestiture (hairs) of the
perigynium are important structures for distinguishing
The fruit of
Carex is a dry, one-seeded indehiscent achene or nut
which grows within the perigynium. Perigynium features aid in fruit
Ecology and distribution
Carex species are found across most of the world, albeit with few
species in tropical lowlands, and relatively few in sub-Saharan
Africa. Most (but not all) sedges are found in wetlands – such as
marshes, calcareous fens, bogs and other peatlands, pond and stream
banks, riparian zones, and even ditches. They are one of the
dominant plant groups in arctic and alpine tundra, and in wetland
habitats with a water depth of up to 50 cm (20 in).
Taxonomy and cytogenetics
Main article: List of
Carex was established by
Carl Linnaeus in his work Species
Plantarum in 1753, and is one of the largest genera of flowering
plants. Estimates of the number of species vary from about 1100 to
Carex displays the most dynamic chromosome evolution
of all flowering plants. Chromosome numbers range from n = 6
to n = 66, and over 100 species are known to show variation
in choromosome number within the species, with differences of up to 10
chromosomes between populations.
Carex has been divided into subgenera in a number of ways. The most
influential was Georg Kükenthal's classification using four subgenera
– Carex, Vignea, Indocarex and Primocarex – based primarily on the
arrangement of the male and female flowers. There has been
considerable debate about the status of these four groups, with some
species being transferred between groups and some authors, such as
Kenneth Kent Mackenzie, eschewing the subgenera altogether and
dividing the genus directly into sections. The genus is now divided
into around four subgenera, some of which may not, however, be
Carex subg. Carex
Carex subg. Carex – 1450 species, distributed globally
Carex subg. Psyllophora (Degl.) Peterm. (equivalent to Kükenthal's
"Primocarex") – 70 species
Carex subg. Vignea
Carex subg. Vignea (P. Beauv. ex T. Lestib.) Peterm. – 350 species,
Carex subg. Vigneastra (Tuckerman) Kükenthal (equivalent to
Kükenthal's "Indocarex") – 100 species, tropical and subtropical
Carex species and cultivars are popular in horticulture, particularly
in shady positions. Native species are used in wildland
habitat restoration projects, natural landscaping, and in sustainable
landscaping as drought-tolerant grass replacements for lawns and
garden meadows. Some require damp or wet conditions, others are
relatively drought-tolerant. Propagation is by seed or division in
A mix of dried specimens of several species of
Carex (including Carex
vesicaria) have a history of being used as thermal insulation in
footwear (such as skaller used by
Sami people  and
Sennegrass is one of the names for such mixes. During the
first human expedition to the South Pole in 1911, such a mix were used
in skaller, when camps had been set (after each stretch of travelling
had been completed). Carsten Borchgrevink of the British Antarctic
Expedition 1898-1900 reported “I found the
Lapps method of never
using socks in their Finn boots answered well. Socks are never used in
Finnmarken in winter time, but ‘senne grass’ which they, of
course, had a special method of arranging in the ‘komager’ (Finn
boots) … if you get wet feet while wearing the grass in the
‘komager’ you will be warmer than ever, as the fresh grass will,
by the moisture and the heat of your feet, in a way start to burn or
produce its own heat by spontaneous combustion. The great thing seems
to be to arrange the grass properly in the boots, and although we all
tried to imitate the Finns in their skill at this work, none of us
felt as warm on our feet as when they had helped us.”
Species serve as a food source for numerous animals, and some are
used as a livestock hay.
^ Ilkka Kukkonen; Heikki Toivonen (1988). "Taxonomy of wetland
carices". Aquatic Botany. 30 (1–2): 5–22.
^ Andrew L. Hipp (2007). "Nonuniform processes of chromosome evolution
in sedges (Carex: Cyperaceae)" (PDF). Evolution. 61 (9): 2175–2194.
doi:10.1111/j.1558-5646.2007.00183.x. PMID 17767589.
^ a b c d e f g h i j Robert H. Mohlenbrock; Paul Wayne Nelson (1999).
"Introduction". Sedges: Carex. Volume 14 of The Illustrated flora of
Illinois. Southern Illinois University Press. pp. 3–7.
^ a b c d e f Peter W. Ball; A. A. Reznicek (2002). "
Sp. Pl. 2: 972. 1753; Gen. Pl. ed. 5, 420. 1754". Magnoliophyta:
Commelinidae (in part): Cyperaceae.
Flora of North America North of
Mexico. 23. Oxford University Press. pp. 254–258.
^ Amjad Almusaed (2010). Biophilic and Bioclimatic Architecture:
Analytical Therapy for the Next Generation of Passive Sustainable
Architecture. Springer. p. 52. ISBN 978-1-84996-534-7.
^ a b c d A. C. Jermy; D. A. Simpson; M. J. Y. Foley; M. S. Porter
(2007). "General structure of Cyperaceae". Sedges of the British
Isles. BSBI Handbook No. 1 (3rd ed.). Botanical Society of the British
Isles. pp. 2–26. ISBN 978-0-901158-35-2.
^ David G. Frodin (2004). "History and concepts of big plant genera".
Taxon. 53 (3): 753–776. doi:10.2307/4135449.
^ Andrew L. Hipp; Paul E. Rothrock; Eric H. Roalson (2009). "The
evolution of chromosome arrangements in
Carex (Cyperaceae)" (PDF). The
Botanical Review. 75 (1): 96–109.
^ a b c Julian R. Starr; Stephen A. Harris; David A. Simpson (2008).
"Phylogeny of the unispicate taxa in
Cyperaceae Tribe Cariceae II: the
limits of Uncinia". In Robert F. C. Naczi; Bruce A. Ford. Sedges:
Uses, Diversity, and Systematics of the
Cyperaceae (PDF proof).
Monographs in Systematic Botany. 180. Missouri Botanical Garden Press.
^ a b c Dai Lunkai; Liang Songyun; Zhang Shuren; Tang Yancheng; Tetsuo
Koyama; Gordon C. Tucker. "33.
Carex Linnaeus, Sp. Pl. 2: 972. 1753.
薹草属 tai cao shu". Acoraceae through
Cyperaceae (PDF). Flora of
China. 23. Harvard University Press. pp. 285–461.
^ Judy Lowe (2012). "Carex". Tennessee & Kentucky Garden Guide:
the Best Plants for a Tennessee or Kentucky Garden (2nd ed.). Cool
Springs Press. p. 178. ISBN 978-1-59186-537-7.
^ Frances Tenenbaum, ed. (2003). "Carex". Taylor's Encyclopedia of
Garden Plants. Houghton Mifflin Harcourt. pp. 74–75.
^ "Grasses and grasslike plants". Native Sons. Retrieved May 22,
^ RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling
Kindersley. 2008. p. 1136. ISBN 1-4053-3296-4.
^ a b "Bruk av land og vann i Finnmark i historisk perspektiv" [The
use of land and water in Finnmark in historical perspective]. Norges
Offentlige Utredninger (in Norwegian). Norwegian Ministry of Justice
and Public Security. 1994 (21). 1994.
^ Ole Mathismoen (December 14, 2011). "Blir ikke varm i rått
Aftenposten (in Norwegian). p. 17. ... skalder
med senegress fra Kautokeino til bruk når de hadde slått leir.
^ Borchgrevink, Carston (1980). First on the Antarctic continent.
Being an account of the British Antarctic Expedition, 1898 – 1900.
London: Hurst and Co.
^ Ronald W. Crites; E. Joe Middlebrooks; Sherwood C. Reed (2005).
Natural Wastewater Treatment Systems. CRC Press. p. 263.
^ Heinjo Lahring (2003). Water and
Wetland Plants of the Prairie
Provinces. University of Regina Press. p. 114.
^ Joel Greenberg (2010). Of Prairie, Woods, and Water: Two Centuries
of Chicago Nature Writing. ReadHowYouWant.com. p. 206.
Wikimedia Commons has media related to Carex.
Jones, T. M. (2010) Interactive Visual Identification to Carices
of North America @ LSU Herbarium
eMonocot Cyperaceae, a portal to updated classification, images,
species descriptions, and vetted specimen data for the entire sedge
family, with a strong focus on Carex.