|Dwarf umbrella-sedge, Cyperus albostriatus|
They are annual or perennial plants, mostly aquatic and growing in still or slow-moving water up to 0.5 m deep. The species vary greatly in size, with small species only 5 cm tall, while others can reach 5 m in height. Common names include papyrus sedges, flatsedges, nutsedges, umbrella-sedges and galingales. The stems are circular in cross-section in some, triangular in others, usually leafless for most of their length, with the slender grass-like leaves at the base of the plant, and in a whorl at the apex of the flowering stems. The flowers are greenish, and wind pollinated; they are produced in clusters among the apical leaves. The seed is a small nutlet.
Cyperus species are eaten by the larvae of some Lepidoptera species, including Batrachedra cuniculata. They also provide an alternative food source for Bicyclus anynana larvae. The seeds and tubers are an important food for many small birds and mammals.
Cyperus microcristatus (from Cameroon) and C. multifolius (native to Panama and Ecuador) are possibly extinct; the former was only found once, in 1995, and the latter has not been seen in the last 200 years. The "true" papyrus sedge of Ancient Egypt, C. papyrus subsp. hadidii, is also very rare today due to draining of its wetland habitat; feared extinct in the mid-20th century, it is still found at a few sites in the Wadi El Natrun region and northern Sudan.
Around 700 species are currently recognised in the genus Cyperus.
Use by humans
Papyrus sedge (C. papyrus) of Africa was of major historical importance in providing papyrus. C. giganteus, locally known as cañita, is used by the Yokot'an Maya of Tabasco, Mexico, for weaving petates (sleeping mats) and sombreros. C. textilis and C. pangorei are traditionally used to produce the typical mats of Palakkad in India, and the makaloa mats of Niihau were made from C. laevigatus.
The Chufa flatsedge (C. esculentus) has edible tubers and is grown commercially for these; they are eaten as vegetables, made into sweets, or used to produce the horchata of the Valencia region. Several other species – e.g. Australian bush onion (C. bulbosus) – are eaten to a smaller extent. For some Northern Paiutes, Cyperus tubers were a mainstay food, to the extent that they were known as tövusi-dökadö ("nutsedge tuber eaters").[verification needed]
Most species are of little economic value. Some are grown as ornamental or pot plants, namely the umbrella papyrus (C. alternifolius), the dwarf umbrella-sedge (C. albostriatus, formerly called C. diffusus), and related species. There is increasing interest in the larger, fast-growing species as crops for paper and biofuel production.
- Amphoe Nong Prue, a district in Thailand. The name of its capital Nong Prue (หนองปรือ) literally means "Cyperus swamp".
- The sedge Carex pseudocyperus is a related plant convergent in appearance to Cyperus.
- "Cyperus L., Sp. Pl.: 44 (1753)". Kew World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew. Retrieved 22 March 2015.
- Win Huygh, Isabel Larridon, Marc Reynders, A. Muthama Muasya, Rafaël H. A. Govaerts, David A. Simpson & Paul Goetghebeur (2010). "Nomenclature and typification of names of genera and subdivisions of genera in Cypereae (Cyperaceae): 1. Names of genera in the Cyperus clade". Taxon 59 (6): 1883–1890.
- Gordon C. Tucker, Brian G. Marcks & J. Richard Carter (2003). "Cyperus Linnaeus, Sp. Pl. 1: 44. 1753; Gen. Pl. ed. 5, 26. 1754". In Flora of North America Editorial Committee. Magnoliophyta: Commelinidae (in part): Cyperaceae. Flora of North America 23. Oxford University Press. pp. 141–191.
- C. D. Adams (1994). "5. Cyperus L.". In G. Davidse, M. Sousa Sánchez & A. O. Chater. Flora Mesoamericana 6. Mexico City: Universidad Nacional Autónoma de México. pp. 423–440.
- G. E. Schatz, S. Andriambololonera, Andrianarivelo, M. W. Callmander, Faranirina, P. P. Lowry, P. B. Phillipson, Rabarimanarivo, J. I. Raharilala, Rajaonary, Rakotonirina, R. H. Ramananjanahary, B. Ramandimbisoa, A. Randrianasolo, N. Ravololomanana, Z. S. Rogers, C. M. Taylor & G. A. Wahlert (2011). Catalogue of the Vascular Plants of Madagascar. Monographs in Systematic Botany. Missouri Botanical Garden.
- Rinny E. Kooi, Paul M. Brakefield & William E. M.-T. Rossie (1996). "Effects of food plant on phenotypic plasticity in the tropical butterfly Bicyclus anynana". Entomologia Experimentalis et Applicata 80: 149–151. doi:10.1111/j.1570-7458.1996.tb00906.x.
- "Cyperus". The Plant List. Retrieved 20 March 2015.
- John M. Riddle (1994). Contraception and Abortion from the Ancient World to the Renaissance. Cambridge, Massachusetts: Harvard University Press. ISBN 978-0674168763.
|Wikimedia Commons has media related to Cyperus.|
- CYPERUS interactive identification key by D. M. Ferguson @ LSU Herbarium
- CYPERACEAE interactive identification keys @ LSU Herbarium
- Flora of China Vol. 23 Page 219, 莎草属 suo cao shu, Cyperus Linnaeus, Sp. Pl. 1: 44. 1753.
- Flora of Pakistan, V. 206 Page 89, Cyperus Linnaeus, Sp. Pl. 1: 44. 1753; Gen. Pl., ed. 5: 26. 1754; Boiss., Fl. Or. 5: 363. 1882; C.B.Clarke in Hook.f., Fl. Brit. Ind. 6: 597. 1893; R. R. Stewart, l.c. 86. 1972; Kukkonen in Rech.f., Fl. Iranica 173: 85. 1998.