Eurasian Watermilfoil
Description
Eurasian watermilfoil (Myriophyllum spicatum) is an “exotic” aquatic plant. Exotic meaning that it is not native to this area, but it is native to Europe, Asia and Northern Africa. Eurasian watermilfoil has slender stems whorled by submersed feathery leaves and tiny flowers produced above the water surface. The flowers are located in the axils of the floral bracts, and are either four-petaled or without petals. The leaves are threadlike, typically uniform in diameter, and aggregated into a submersed terminal spike. The stem thickens below the inflorescence and doubles its width further down, often curving to lie parallel with the water surface. The fruits are four-jointed nut-like bodies. Without flowers or fruits, Eurasian watermilfoil is nearly impossible to distinguish from Northern watermilfoil. Eurasian watermilfoil has 9-21 pairs of leaflets per leaf, while Northern milfoil typically has 7-11 pairs of leaflets. Coontail [which is native and prevalent in Liberty Lake] is often mistaken for the milfoils, but does not have individual leaflets (Wisconsin Department of Natural Resources, 1999).
Milfoil/Invasive Plant Management
Wednesday, August 28 – Thursday, August 29, 2024
This years invasive plant treatment is scheduled for the following dates:
August 28 – August 29, 2024.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 36 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake Business and Residential Notice 2024 – Mailed to shoreline residents, 8/16/2024
Liberty Lake Herbicide Treatment Notice Map 2024
LAKE USE IMPACTS
1. Boats – please minimize or curtail boat traffic during the treatment, as well as for the 24-hour period after. This helps to minimize wave action, which moves the herbicide away from the intended treatment zones.
2. Swimming – due to the products we will be using, there will be NO swim restriction on the entire lake, following the application.
CHEMICALS PLANNED FOR USE
ProcellaCOR (Florpyrauxifen-Benzyl) – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
AquaTechnex (Applicator), 509-960-8133
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
Tuesday, August 15 – Wednesday, August 16, 2023
This years invasive plant treatment is scheduled for the following dates:
August 15 – August 16, 2023.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 10 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake Business and Residential Notice 2023 – Mailed to shoreline residents, 7/21/2023
Liberty Lake Herbicide Treatment Notice Map 2023
LAKE USE IMPACTS
1. Boats – please minimize or curtail boat traffic during the treatment, as well as for the 24-hour period after. This helps to minimize wave action, which moves the herbicide away from the intended treatment zones.
2. Swimming – due to the products we will be using, there will be NO swim restriction on the entire lake, following the application.
CHEMICALS PLANNED FOR USE
ProcellaCOR (Florpyrauxifen-Benzyl) – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
AquaTechnex (Applicator), 509-960-8133
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
Tuesday, September 6 – Friday, September 16, 2022
This years invasive plant treatment is scheduled for the following dates:
September 6 – September 16, 2022.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 13 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake Business and Residential Notice 2022 – Mailed to shoreline residents, 8/29/2022
Liberty Lake Herbicide Treatment Notice Map 2022
LAKE USE IMPACTS
1. Boats – please minimize or curtail boat traffic during the treatment, as well as for the 24-hour period after. This helps to minimize wave action, which moves the herbicide away from the intended treatment zones.
2. Swimming – due to the products we will be using, there will be NO swim restriction on the entire lake, following the application.
CHEMICALS PLANNED FOR USE
ProcellaCOR (Florpyrauxifen-Benzyl) – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
AquaTechnex (Applicator), 509-960-8133
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
TODAY Treatment Occurred:
Tuesday, August 31 – Wednesday, September 1, 2021
24hr SWIM RESTRICTIONS ARE LIFTED 9/1/2021 @ 1:00p
This years invasive plant treatment is scheduled for the following dates:
August 31 – September 3, 2021.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 34 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake Business and Residential Notice 2021 – Mailed to shoreline residents, 8/17/2021
Liberty Lake Herbicide Treatment Notice Map 2021 – Mailed to shoreline residents, 8/17/2021
Swim Restrictions – Applies to ENTIRE LAKE
- This swim restriction begins when herbicide is placed in the lake, and the 24 hour clock starts when the treatment effort is complete. LLSWD tracks when this time begins/ends, so please feel free to contact our office to find out when the restriction will be lifted for the lake.
LAKE USE IMPACTS
1. Boats – please minimize or curtail boat traffic during the treatment, as well as for the 24-hour period after. This helps to minimize wave action, which moves the herbicide away from the intended zones.
2. Swimming – due to the products we will be using, there will be a 24-hour swim restriction on the entire lake, following the application.
3. Irrigation – if you are one of the very few that have a historical water right that you use for irrigating your landscape, you will want to turn your pump off until 9/5.
CHEMICALS PLANNED FOR USE
Diquat – Manufacturer’s product label
Flumioxazin – Manufacturer’s product label
Aquathol – Manufacturer’s product label
Hydrothol 191 – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
Lakeland Restoration Services, LLC (Applicator), 877-273-6674
lakeland@lakelandrs.com
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
PLANNED Treatment Dates:
Tuesday, August 18 – Wednesday, August 19, 2020
Liberty Lake Aquatic Invasive Control – 2020 Update Letter
– A brief rundown of what we are doing this summer to address our 2 invasive plant species found in Liberty Lake.
This years invasive plant treatment is scheduled for the following dates:
August 18 – 19th, and/or August 25 – 26, 2020.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 28 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake Business and Residential Notice 2020 – Mailed to shoreline residents, 8/3/2020
Liberty Lake Herbicide Treatment Notice Map 2020 – Mailed to shoreline residents, 8/3/2020
Swim Restrictions – Map showing 400 foot buffer zone – To be posted online in the coming days….. x/xx/201x
- This recommended 24-hour swim restriction begins when herbicide is placed in each treatment area. LLSWD tracks when this time begins/ends, so please feel free to contact our office to find out when the restriction will be lifted in a certain part of the lake.
CHEMICALS PLANNED FOR USE
Triclopyr – Manufacturer’s product label
Fluridone – Manufacturer’s product label
Hydrothol 191 – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
Lakeland Restoration Services, LLC (Applicator), 877-273-6674
lakeland@lakelandrs.com
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
PLANNED Treatment Dates:
Wednesday, July 10 – Thursday, July 11, 2019
We are treating earlier in the year than typical due to a few factors:
- There is a new invasive plant in Liberty Lake: Curly Leaf Pondweed (CLP), initially identified by LLSWD staff in August 2018.In June 2019, a plant survey was done to further characterize the spread of CLP; we found it present along the entire shoreline! Luckily, CLP is not in dense stands…this means we may be able to get a hold of the population before it finds its niche on our soft, sandy lake bottom.
This plant needs to be addressed ASAP – before the plants begin producing seeds/turions. - We are using a contractor (Lakeland Restoration Services, LLC) to apply the herbicide this year, rather than LLSWD staff. This is due to the large acreage that is being targeted, as well as the special chemical mixture that is needed to target Curly Leaf Pondweed.
This years invasive plant treatment is scheduled for the following dates:
July 10 – 11th, and/or July 17 – 18, 2019.
- The treatment should take 1 day
- We will be working as early in the schedule/week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 39 acres of the lake shoreline (littoral zone) will have aquatic herbicide applied
Liberty Lake_Business and Residential Notice_2019 – Mailed to shoreline residents, 6/26/2019
Liberty Lake_Herbicide Treatment Notice Map_2019 – Mailed to shoreline residents, 6/26/2019
Swim Restrictions – Map showing 400 foot buffer zone – To be posted online in the coming days….. x/xx/201x
- This recommended 24-hour swim restriction begins when herbicide is placed in each treatment area. LLSWD tracks when this time begins/ends, so please feel free to contact our office to find out when the restriction will be lifted in a certain part of the lake.
CHEMICALS PLANNED FOR USE
Weedar 64 – Manufacturer’s product label
Hydrothol 191 – Manufacturer’s product label
CONTACT INFORMATION
Questions?
Please contact Liberty Lake Sewer and Water District
-or-
Lakeland Restoration Services, LLC (Applicator), 877-273-6674
lakeland@lakelandrs.com
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
PLANNED Treatment Dates:
Monday, August 13 – Tuesday, August 14, 2018
This years milfoil treatment is scheduled for the following dates:
August 13 – 17, and/or August 20 – 24, 2018.
- The treatment should take 2 days
- We will be working as early in the week as possible
- The range of days is to account for any type of weather delays, or adverse environmental conditions which may occur (wind, rain, thunderstorms, algae, etc.)
- A total of 10 acres of the lake will have selective aquatic herbicide applied
Liberty Lake_Business and Residential Notice_2018 – Mailed to shoreline residents, 7/26/2018
Liberty Lake_Herbicide Treatment Notice Map_2018 – Mailed to shoreline residents, 7/26/2018
Swim Restrictions – Map showing 400 foot buffer zone – Posted online, 8/09/2018
– This recommended 24-hour swim restriction begins when herbicide is placed in each treatment area. LLSWD tracks when this time begins/ends, so please feel free to contact our office to find out when the restriction will be lifted in a certain part of the lake.
SculpinG_2,4-D – Manufacturer’s product label
Questions?
Contact the Applicator, Liberty Lake Sewer and Water District
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
PLANNED Treatment Dates:
Monday August 14th – Tuesday August 15th, 2017
This years milfoil treatment is scheduled for the following dates:
August 14th – 18th, and/or August 21st – 25th, 2017.
- The treatment should take 2 days
- We will be working as early in the week as possible
- The range of days is to account for any type of weather delays which may occur (wind, rain, thunderstorms, algae, etc.)
Liberty Lake_Herbicide Treatment Notice Map_2017 – Mailed to shoreline residents, 7/23/2017
Swim Restrictions – Map showing 1/4 mile buffer zone, x/x/xxxx
SculpinG_2,4-D – Manufacturer’s product label, 8/2/2017
AquaNeat_Glyphosate – Manufacturer’s product label, 8/2/2017
Questions?
Contact the Applicator, Liberty Lake Sewer and Water District
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
Treatment Dates:
Tuesday, August 16th – Wednesday, August 17th, 2016
This year’s milfoil treatment is scheduled for the following dates:
August 16th – 19th, and/or August 22nd – 26th, 2016.
- The treatment should take 2 days
- We will be working as early in the week as possible
- The range of days is to account for any type of weather delays which may occur (wind, rain, thunderstorms, algae, etc.)
Liberty Lake_Herbicide Treatment notice_2016 – Mailed to shoreline residents, 8/5/2016
SwimRestriction Map_2016 – Map showing 1/4 mile buffer zone, 8/5/2016
SculpinG_2,4-D – Manufacturers product label, 8/5/2016
AquaNeat_Glyphosate – Manufacturers product label, 8/5/2016
Questions?
Contact the Applicator, Liberty Lake Sewer and Water District
THIS HERBICIDE TREATMENT IS REGULATED UNDER A PERMIT ISSUED BY THE WASHINGTON DEPARTMENT OF ECOLOGY, PERMIT NO.: WAG994095
Problems
Eurasian watermilfoil reproduces by fragmentation, thus it does not rely on seed for reproduction. This reproduction allows for the plant fragments to be dispersed and carried by water currents and wind or inadvertently picked up by boaters. Milfoil reproduces extremely rapidly and can infest an entire lake within two years of introduction to the system (Washington State Department of Ecology, 2002). Milfoil is most commonly transported via boats, motors, trailers, bilges, live wells, or bait buckets, and if moist can stay alive for weeks.
Eurasian milfoil is very invasive and can provide only a single habitat by replacing the native plant species and in turn threatening the integrity of aquatic communities. It also inhibits the aesthetic and recreational uses like swimming, boating, and fishing. Severely infested waters display a dense yellow-green matt of vegetation and give off the appearance that the water is “infested” or “dead.” The decomposition of the plant mass at the end of the season results in nitrogen and phosphorus loading, and the cycling of nutrients from sediments to the water column by Eurasian watermilfoil may lead to deteriorating water quality and algae blooms of infested lakes (Wisconsin Department of Natural Resources, 1999).
Eurasian watermilfoil was believed to have been introduced to the eastern United States around the 1940s, but it is possible that it may have arrived as early as the late 1800s. The first known herbarium milfoil specimen in Washington was collected from Lake Meridian near Seattle in 1965 (Washington State Department of Ecology, 2002).
Distribution
Eurasian watermilfoil has been spreading throughout Liberty Lakes’ perimeter since it was first discovered in 1995. Removal was controlled by divers until 1997, when the infestation became to great to handle, then Aqua-Kleen® Granular 2,4-D became the primary treatment. Each spring, aquatic weed diving surveys are conducted by Clearwater Scuba, L.L.C. and the LLSWD to evaluate potential growth and effective treatment. 2,4-D treatments have occurred since 1998 in northern and southern sections of the lake where the infestation remains in the shallow shoreline areas of approximately 1 to 3 meters in depth.
It is of concern of the district and the community that if the density of the milfoil increases that it could potentially crowd out native vegetation and impede human recreation and aquatic habitat. Another very important concern of the district and the community is the potential for the spread of Eurasian watermilfoil to other lakes in the surrounding area. There are other waterbodies in the area that currently are not infested with Eurasian watermilfoil, and it is our concern to reduce the chances of infestation, or reduce the further spread of milfoil to other lakes or waterbodies. Liberty Lake is a popular recreational lake for the greater community and residents, unified with its history; the community has a strong affinity to protect it. Thus in response to the numerous concerns, the Liberty Lake Sewer and Water District wants to evaluate all control options and means of management for the invasive weed for suppression and future control of milfoil within Liberty Lake.
Management
The Liberty Lake Sewer and Water District has taken the community concerns acutely and researched the means of management for the invasive weed. In October of 2002, the Liberty Lake Sewer and Water District was awarded a grant by the Washington State Department of Ecology (DOE) to develop an Integrated Aquatic Weed Management Plan for Liberty Lake. The report is the result of collaboration and research for a probable solution to the Eurasian watermilfoil infestation at Liberty Lake. As part of the plan’s development, the Liberty Lake Sewer and Water District encouraged representation from the community, neighboring lake communities, aquatic consultants, Washington State Department of Ecology, Washington State Department of Natural Resources, and the Washington Department of Fish and Wildlife. A special thanks to the Washington State Department of Ecology and Kathy Hamel for their time and funding to make this project possible.
More recently, the Liberty Lake Sewer and Water District received grant funding for the Liberty Lake Milfoil Management Implementation Project from Washington Department of Ecology’s Aquatic Weed Management Fund. Up to $100,000 was offered to the Liberty Lake Sewer and Water District to cover 75 percent of the eligible project costs for the Liberty Lake Milfoil Management Implementation Project for five years (2004-2009). The project funded was implementation of the Aquatic Weed Management Plan that was drafted and funded in October 2003. It is the intent of the Liberty Lake Milfoil Management Implementation Project to implement the management strategy outlined in the plan. The full text of the Liberty Lake Integrated Aquatic Weed Management Plan is available below.
For more information, please contact Liberty Lake Sewer and Water District.
Public education is an important element in the control of aquatic nuisance plants. Signs have been developed by DOE to bring attention to the Eurasian watermilfoil infestation in lakes and to show fishermen and other lake users how to avoid transporting aquatic plants from one lake to another. These signs have been installed at the public boat launch at Liberty Lake. Educational flyers are available at the District’s administrative building and have been distributed to residents and concerned citizens. Mailings and newspaper articles are also written to inform residents of the infestation and best management practices that can be applied to limit the spread and future degree of infestation.
The Sewer and Water District recognizes that the effective management will be an on-going concern and will require a long-term commitment. The Liberty Lake Sewer and Water District is willing to fund the follow-up activities necessary to ensure continued milfoil eradication and management. Monitoring of the plant community and beneficial uses such as fishing, boating, and swimming needs to be continued.
Other Information
For more information about Eurasian watermilfoil (Myriophyllum spicatum), please check out the links listed below.