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purple nutsedge (Cyperus rotundus)
NOT KNOWN TO OCCUR IN OREGON PLEASE CALL 1-866-INVADER IF YOU SUSPECT YOU HAVE FOUND THIS SPECIES

USDA Symbol: CYRO

ODA rating: A
purple nutsedge risk assessment
Noxious weed listing process


 
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Images courtesy of Rich Old, XID Services

 
 
If images are downloaded and used from the ODA web site please be sure to credit the photographer.
 
Description
Perennial; grows 1 to 2 feet high. Stems 3 cornered and generally longer than the basal leaves. Leaves grass-like, 1/8 to 1/3 inch wide and 2 to 6 inches in length. Inflorescence consists of numerous purple spikelets. Underground tubers oblong, covered by persistent reddish scales and often formed in chains.
 
Impacts
Purple nutsedge is considered one of the world's top 10 agricultural weeds. It thrives in moist conditions, most notably in the sandy soils found on river bottoms; areas which are critical for food production in many third world countries. As a nutsedge, it forms nut-like turions which resist herbicide treatments and tillage. In infested countries, it is commonly found in turf, ornamental areas, cultivated fields and ditch banks. In Oregon it is considered a potential threat to containerized horticultural products.
 
Introduction
This plant was introduced to the U.S. from Europe and can be found on virtually every continent.
 
Distribution
This species is not yet known to occur in Oregon.
 
Biological controls
Biological control agents are not used on "A" listed weeds in Oregon. If this weed is found in the state it will be managed for eradication or containment.
 
Informational links
Oregon WeedMapper