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European water chestnut (Trapa natans L)
NOT KNOWN TO OCCUR IN OREGON PLEASE CALL 1-866-INVADER IF YOU SUSPECT YOU HAVE FOUND THIS SPECIES
USDA Symbol: TRNA

ODA rating: A

European water chestnut risk assessment
Noxious weed listing process
 

Other common names
Singhara Ling, bullnut
 
Click on photo below to view larger image
Image courtesy of alfred Cofrancesco, U.S. Army Corps of Engineers
Image courtesy of Leslie J. Mehrhoff, University of Connecticut
Image courtesy of  Leslie J. Mehrhoff, University of Connecticut
 
If images are downloaded and used from the ODA web site please be sure to credit the photographer.
 
Description
Annual aquatic plant. Upper floating leaves diamond-shaped with toothed edges, arranged on inflated, spongy stalks and occur in clusters up to 20 inches across. Submersed leaves long and narrow or often replaced with green feather-like structures. Flowers small, solitary and white to light purple. Fruit a large swollen nut with two to four sharp spines.
 
Impacts
This plant is a fierce competitor in shallow bodies of water possessing soft, muddy rooting substrates. In the Northeast it creates nearly impenetrable mats across wide areas of water creating barriers to boaters, swimmers and fisherman alike. Spiked nuts drift to shore where their sharp spines may hurt bare feet. Mono-cultures severely limit light penetration and water mixing, creating conditions of reduced oxygen levels which may increase the potential for fish kills. It is of little value to waterfowl.
 
Distribution in Oregon
No sites have been identified in Oregon at this time.
 
Biological controls
Biological control agents are not used on "A" listed weeds in Oregon.
 
Informational links:
Oregon WeedMapper
European water chestnut printable trifold(pdf)