The Cyperaceae are a family of

graminoid In botany and ecology, graminoid refers to a herbaceous plant with a grass-like morphology, i.e. elongated culms with long, blade-like leaves. They are contrasted to forbs, herbaceous plants without grass-like features. The plants most ofte ...

(grass-like),

monocotyledon Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one ...

ous flowering plants known as sedges. The

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

is large, with some 5,500 known species described in about 90

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

, the largest being the "true sedges" genus ''

Carex ''Carex'' is a vast genus of more than 2,000 species of grass-like plants in the family Cyperaceae, commonly known as sedges (or seg, in older books). Other members of the family Cyperaceae are also called sedges, however those of genus ''Carex'' ...

'' with over 2,000 species. These species are widely distributed, with the centers of diversity for the group occurring in

tropic The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

and tropical

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

. While sedges may be found growing in almost all environments, many are associated with

wetlands A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The p ...

, or with poor soils.

Ecological communities In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time, also known as a biocoenosis, biotic community, biological community, ecological community ...

dominated by sedges are known as sedgelands or sedge meadows. Some species superficially resemble the closely related rushes and the more distantly related

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...

es. Features distinguishing members of the sedge family from grasses or rushes are stems with triangular cross-sections (with occasional exceptions, a notable example being the

tule ''Schoenoplectus acutus'' (syn. ''Scirpus acutus, Schoenoplectus lacustris, Scirpus lacustris'' subsp. ''acutus''), called tule , common tule, hardstem tule, tule rush, hardstem bulrush, or viscid bulrush, is a giant species of sedge in the p ...

which has a round cross-section) and leaves that are spirally arranged in three ranks. In comparison, grasses have alternate leaves, forming two ranks. Some well-known sedges include the water chestnut (''

Eleocharis dulcis ''Eleocharis dulcis'', the Chinese water chestnut or water chestnut, is a grass-like sedge native to Asia, tropical Africa, and Oceania. It is grown in many countries for its edible corms. The water chestnut is not a nut, but an aquatic v ...

'') and the papyrus sedge (''

Cyperus papyrus ''Cyperus papyrus'', better known by the common names papyrus, papyrus sedge, paper reed, Indian matting plant, or Nile grass, is a species of aquatic flowering plant belonging to the sedge family Cyperaceae. It is a tender herbaceous perenn ...

''), from which the writing material

papyrus Papyrus ( ) is a material similar to thick paper that was used in ancient times as a writing surface. It was made from the pith of the papyrus plant, '' Cyperus papyrus'', a wetland sedge. ''Papyrus'' (plural: ''papyri'') can also refer to ...

was made. This family also includes cotton-grass (''

Eriophorum ''Eriophorum'' (cottongrass, cotton-grass or cottonsedge) is a genus of flowering plants in the family Cyperaceae, the sedge family. They are found throughout the arctic, subarctic, and temperate portions of the Northern Hemisphere in acid b ...

''), spike-rush (''

Eleocharis ''Eleocharis'' is a virtually cosmopolitan genus of 250 or more species of flowering plants in the sedge family, Cyperaceae. The name is derived from the Greek words ἕλειος (''heleios''), meaning "marsh dweller," and χάρις (''charis'' ...

''), sawgrass (''

Cladium ''Cladium'' (fen-sedge, sawgrass or twig-sedge) is a genus of large sedges, with a nearly worldwide distribution in tropical and temperate regions. These are plants characterized by long, narrow (grass-like) leaves having sharp, often serrated ( ...

''), nutsedge or nutgrass (''

Cyperus rotundus ''Cyperus rotundus'' (coco-grass, Java grass, nut grass, purple nut sedge or purple nutsedge, red nut sedge, Khmer ''kravanh chruk''Martin, Robert & Pol Chanthy, 2009''Weeds of Upland Cambodia'', ACIAR Monagraph 141, Canberra.) is a species of ...

'', a common lawn weed), and white star sedge ('' Rhynchospora colorata'').

Genera

, 88 genera are accepted in Kew's

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

References

External links

Cyperaceae
at th
''Angiosperm Phylogeny Website''
{{Authority control Poales families