 |
Ada County Weed Pest and Mosquito Abatement
Aquatic Noxious Weeds - Eurasian Watermilfoil
|
Eurasian Watermilfoil (Myriophyllum spicatum L.) is the first truly aquatic plant listed among Idaho’s noxious weeds list. This invasive and troublesome weed has infested several waterways in Ada County. If you know of, or are responsible for, a water-body that may be infested with Eurasian Watermilfoil, please contact us regarding possible treatments. Fill out this Request for Inspection Form and we will evaluate the area.
Eurasian Watermilfoil, an invasive plant introduced from Eurasia and Africa, is now found over much of the United States. It’s suspected that the first U.S. infestation occurred in the 1940s from vegetation that possibly escaped from an aquarium. Eurasian Watermilfoil is a perennial weed that forms dense, floating mats that eventually clog the waterways prohibiting native plant growth and inhibiting recreation. Throughout the summer, the weed’s feathery stems can grow up to 33 feet from the lakebed to the water surface. In Ada County the plant has been known to stay green throughout the winter, but it typically over-winters as a pale brown plant that lies on the bottom of the waterway.
Watermilfoil can be carried from pond to pond by wildlife or watercraft. The most important step to prevent the spread of Eurasian Watermilfoil is to clean boats and water trailers of ALL plant debris when leaving a waterway. Preferably the boat, bilge, and trailer will be inspected before it is launched in another waterway as well.
Controlling Eurasian Watermilfoil:
There are two forms of biological controls for Eurasian Watermilfoil, but neither is truly viable in Ada County since they are expensive, have the potential to adversely impact the environment, and are not shown to adequately control the noxious weeds.
Dredging and Mechanical Control Methods:
Large harvesting equipment can be used to mechanically remove Watermilfoil in some areas, and underwater divers can physically remove the plant from the water. Dredging can be expensive and does not offer long-term control without modification to the lakebed to prevent re-infestation.
Chemical Control Methods:
Some herbicide applications can control or possibly eradicate Eurasian Watermilfoil. Licensed professional applicators must be consulted before an aquatic herbicide is used. In all efforts to control Eurasian Watermilfoil, it is imperative to exactly follow all label instructions, guidelines and restrictions. While some products use similaractive ingredients to terrestrial herbicides, their formulations and instructions for use are different.
Alternative Revegetation:
Ada County Noxious Weed Control will continue an aggressive revegetation program that incorporates plants that may improve wildlife habitat to reduce the level of infestation by Eurasian Watermilfoil.
If you have questions about Eurasian Watermilfoil or how to control other aquatic noxious weeds, please contact our office.
|
Ada County Weed Pest and Mosquito Abatement
Aquatic Noxious Weeds - Eurasian Watermilfoil
|
Eurasian Watermilfoil (Myriophyllum spicatum L.) is the first truly aquatic plant listed among Idaho’s noxious weeds list. This invasive and troublesome weed has infested several waterways in Ada County. If you know of, or are responsible for, a water-body that may be infested with Eurasian Watermilfoil, please contact us regarding possible treatments. Fill out this Request for Inspection Form and we will evaluate the area.
Eurasian Watermilfoil, an invasive plant introduced from Eurasia and Africa, is now found over much of the United States. It’s suspected that the first U.S. infestation occurred in the 1940s from vegetation that possibly escaped from an aquarium. Eurasian Watermilfoil is a perennial weed that forms dense, floating mats that eventually clog the waterways prohibiting native plant growth and inhibiting recreation. Throughout the summer, the weed’s feathery stems can grow up to 33 feet from the lakebed to the water surface. In Ada County the plant has been known to stay green throughout the winter, but it typically over-winters as a pale brown plant that lies on the bottom of the waterway.
Watermilfoil can be carried from pond to pond by wildlife or watercraft. The most important step to prevent the spread of Eurasian Watermilfoil is to clean boats and water trailers of ALL plant debris when leaving a waterway. Preferably the boat, bilge, and trailer will be inspected before it is launched in another waterway as well.
Controlling Eurasian Watermilfoil:
There are two forms of biological controls for Eurasian Watermilfoil, but neither is truly viable in Ada County since they are expensive, have the potential to adversely impact the environment, and are not shown to adequately control the noxious weeds.
Dredging and Mechanical Control Methods:
Large harvesting equipment can be used to mechanically remove Watermilfoil in some areas, and underwater divers can physically remove the plant from the water. Dredging can be expensive and does not offer long-term control without modification to the lakebed to prevent re-infestation.
Chemical Control Methods:
Some herbicide applications can control or possibly eradicate Eurasian Watermilfoil. Licensed professional applicators must be consulted before an aquatic herbicide is used. In all efforts to control Eurasian Watermilfoil, it is imperative to exactly follow all label instructions, guidelines and restrictions. While some products use similaractive ingredients to terrestrial herbicides, their formulations and instructions for use are different.
Alternative Revegetation:
Ada County Noxious Weed Control will continue an aggressive revegetation program that incorporates plants that may improve wildlife habitat to reduce the level of infestation by Eurasian Watermilfoil.
If you have questions about Eurasian Watermilfoil or how to control other aquatic noxious weeds, please contact our office.