Cyperus rotundus (sedge)

Ecology Distribution Management Info Impact Info References and Links Contacts

General Impact For a detailed account of the impacts of Cyperus rotundus please read: Cyperus rotundus (Purple Nutsedge) Impacts Information. The information in this document is summarised below.          Location Specific Impacts: Pakistan   Agricultural: In Pakistan, purple nutsedge is one of the most common weeds found throughout the Indus valley during the summer season in major field crops such as cotton, sugarcane and maize (Iqbal Cheema & An 2008). Bryson et al. (2003, in Iqbal Cheema & An 2008) reported that purple nutsedge causes seed cotton yield reductions of 62–85%. Amasya (Turkey)   Agricultural: Purple nutsedge is found at greater than 5% frequencies in onion production systems in the province of Amasya, Turkey. United States (USA)   Agricultural: By 1939, uncontrolled purple nutsedge encroachment caused growers to abandon agricultural land (Godfrey 1939, in Webster 2005). Human nuisance: In the USA purple nutsedge is most important in cotton, maize, and home gardens (Bendixen & Nandihalli 1987). Texas (United States (USA))   Agricultural: Herbicides have benefitted the Cyperus species by eliminating interspecific weed competition (Keeley 1987, Webster and Coble 1997b, in Warren & Coble 1999). Purple and yellow nutsedge infestations continue to increase in many Texas peanut fields due to the use of dinitroaniline herbicides, which control most grass and small-seeded broadleaf weeds but have no effect on either nutsedge species (Grichar et al. 1992, Grichar and Nester 1997, in Warren & Coble 1999).