Cyperus erythrorhizos

{{short description|Species of plant}}

{{speciesbox

|name = Redroot flatsedge

|image = Cyperus erythrorhizos UMFS 1.jpg

|status =

|status_system =

|genus = Cyperus

|species = erythrorhizos

|authority = Muhl.

|synonyms_ref =

|synonyms = *Chlorocyperus erythrorhizus (Muhl.) Palla

• Cyperus cupreus J.Presl & C.Presl
• Cyperus occidentalis Torr.
• Cyperus chrysokerkos Steud.
• Cyperus infirmus Boeckeler
• Cyperus halei Torr. ex Britton
• Cyperus spiculatus Alph.Wood
• Cyperus washingtonensis Gand.
• Cyperus erythrorhizos var. cupreus (J.Presl & C.Presl) Kük.
• Cyperus erythrorhizos var. halei (Torr. ex Britton) Kük.
• Cyperus erythrorhizos var. infirmus (Boeckeler) Kük.

}}

Cyperus erythrorhizos is a species of sedge known by the common names red-rooted flatsedge[http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242357655 Flora of North America, Vol. 23 Page 172, Cyperus erythrorhizos Muhlenberg, Descr. Gram. 20. 1817. ] or redroot flatsedge.[https://plants.usda.gov/home/plantProfile?symbol=CYER2 USDA Plants Profile] It is found across much of North America from Maine, Ontario[http://apps.kew.org/wcsp/namedetail.do?name_id=236528 Kew World Checklist of Selected Plant Families] and British ColumbiaDouglas, G.W., Meidinger, D. & Penny, J.L. (2002). Rare Native Vascular Plants of British Columbia, ed. 2: 1-358. Province of British Columbia. south to Tabasco in southern Mexico.Novelo, A. & L. Ramos. 2005. Vegetación acuática. Cap. 5: 111–144. In J. Bueno, F Álvarez & S. Santiago. Biodiversidad del Estado de Tabasco. CONABIO-UNAM, México.Pérez J., L. A., M. Sousa Sánchez, A. M. Hanan-Alipi, F. Chiang Cabrera & P. Tenorio L. 2005. Vegetación terrestre. 65–110. In J. Bueno, F Álvarez & S. Santiago. Biodiversidad del Estado de Tabasco. CONABIO-UNAM, México.Tucker, G. C. 1994. Revision of the Mexican species of Cyperus (Cyperaceae). Systematic Botany Monographs 43: 1–213.Espejo Serna, A. & López-Ferrari, A.R. (1997). Las Monocotiledóneas Mexicanas una Sinopsis Florística 5: 1-98. Consejo Nacional de la Flora de México, México D.F.

Cyperus erythrorhizos is a plant of wet areas such as rivers and ditches, generally at low elevations. It gets its common and scientific names from the red color of its roots. This sedge grows to a maximum of a meter in height, but is usually quite a bit shorter. It may have a number of long, wispy leaves around the base of the plant. The inflorescence may contain one to several spikes, each spike containing 20 to over 100 spikelets. Each spikelet is light greenish brown to reddish brown and is made up of up to 30 bracted flowers. The fruit is a glossy achene about a millimetre long.