Image below shows areas of the lake treated for curly-leaf pondweed in May 2020
Image below shows areas of the lake treated for curly-leaf pondweed in May 2019
Image below shows areas of the lake treated for curly-leaf pondweed in May 2018
Image below shows areas of the lake treated for curly-leaf pondweed in May 2017
Image below shows areas of the lake treated for curly-leaf pondweed in May 2016
Image below shows areas of the lake treated for curly-leaf pondweed in May 2015.
Lake Restoration treated our lake for curly-leaf pondweed on June 1, 2014. Please see image below to view treatment areas.
Public Notice to Fish Trap Lake Property Owners:
The Fish Trap Lake Improvement District (“FTLID”) has contracted to treat curly-leaf pondweed in Fish Trap Lake in 2018.
The Minnesota Department of Natural Resources has granted to the FTLID a waiver of the requirements that the association obtain the signatures of approval of owners of lake-shore property. Instead, the FTLID will notify property owners of the treatment through alternative form[s]. This notice is one form that the FTLID is using to notify property owners. Other forms include notification on the FTLPOA web page, www.fishtraplake.com and during the FTLID’s annual meeting. The annual meeting this year is scheduled for Saturday, June 23, 2018 at 9:00 a.m., at the Scandia Valley Township Hall.
With regard to the treatment for this year, 2018;
- The proposed date for treatment: The date of treatment is determined by the issued permit.
- The target species for the treatment: Curly-leaf Pondweed
- The method of control or product being used: Aquathol K
- How landowners may request that control not occur adjacent to the landowner’s property: If you desire that the treatment of curly-leaf pondweed not occur adjacent to your property, please notify Tom Anderson, FTLID Chairman, immediately at the following address, phone number or email address:
Fish Trap Lake Improvement District
P.O. Box 73
Motley, MN 56466
Notification must be received by May 14, 2018
Professional Lake Management completed treatment of 65 acres (out of a total 70 acres) of curly-leaf pondweed on May 24, 2011.
This page contains a map showing the May 22, 2008 treatment areas, the June 2008 Delineation and treatment safety information.
At the March 7, 2009, Fish Trap Lake Improvement District Board meeting, the board selected Professional Lake Management to treat 55 acres of curly-leaf pondweed. The treatment areas for 2009 will be slightly different than in 2008 due to the fact that after last year’s treatment, the DNR did not observe curly-leaf pondweed in several of the treated areas.
Information from the DNR Website
Invasive, non-native species – Curly-leaf pondweed (Potamogeton crispus)
What is curly-leaf pondweed?
Curly-leaf is a submersed aquatic plant that is not native to North America. It generally grows in 3-10 feet of water. Curly-leaf tolerates low water clarity and will readily invade disturbed areas.
How can I tell if curly-leaf pondweed is in a lake?
Curly-leaf (see picture) is similar in appearance to many native pondweeds commonly found in Minnesota lakes and streams. It can be distinguished from other pondweeds by its unique life cycle. It is generally the first pondweed to come up in spring and dies back in mid-summer.
Where did curly-leaf pondweed come from?
Curly-leaf was first noted in Minnesota about 1910. It probably was accidentally introduced to the state when common carp were intentionally brought to Minnesota. Curly-leaf has been in Minnesota so long that most people do not realize that it is a nonnative species.
Why is curly-leaf pondweed a problem?
In spring, curly-leaf pondweed can form dense mats that may interfere with boating and other recreation on lakes. Curly-leaf also can cause ecological problems because it can displace native aquatic plants. In midsummer, curly-leaf plants usually die back, which results in rafts of dying plants piling up on shorelines, and often is followed by an increase in phosphorus, a nutrient, and undesirable algal blooms. Like other aquatic vegetation, the abundance of curly-leaf varies from year to year depending on environmental conditions, such as winter snow depth, and spring water clarity, which can effect its growth.
How does curly-leaf pondweed spread?
Curly-leaf is believed to spread from one body of water to another primarily by the unintentional transfer of turions, which are hardened stem tips, on plant fragments carried on trailered boats, personal watercraft, etc.
What can be done to prevent the spread of curly-leaf pondweed?
The most important action that you can take to limit the spread of curly-leaf and other non-native aquatic plants is to remove all vegetation from your watercraft before you move it from one body of water to another.
What can be done about problems caused by curly-leaf pondweed?
Past experience in Minnesota and elsewhere has shown that eradication or elimination of curly-leaf pondweed from lakes is not a realistic goal. Nevertheless, problems caused by curly-leaf can be managed using available methods of control. Short-term control of dense mats of curly-leaf that interfere with use of a lake can be obtained using contact herbicides or mechanical harvesting. For information on regulations governing the use of herbicides and mechanical harvesting, please see the brochure entitled “Aquatic Plant Management: A lakeshore owner’s guide to aquatic plant benefits and regulations for their control.” Over the past few years, there has been an increase in the number of lake residents and associations requesting assistance with problems caused by curly-leaf pondweed. More specifically, people want to know whether control can:
- Reduce the lake-wide abundance of curly-leaf pondweed for long periods of time
- Increase the abundance of native submersed aquatic plants, and
- Improve water quality by reducing peaks in concentrations of phosphorous, and associated algal blooms
In response, the DNR has increased its efforts to 1) provide technical assistance to lake residents and 2) evaluate new strategies for control of curly-leaf pondweed. The evaluation of new methods has been focused on experimental lake-wide treatments of curly-leaf, which are done early in the spring. Since these treatments require monitoring that is expensive in terms of both time and money, there are a limited number of them in Minnesota. Until the results from multi-year monitoring of current lake-wide treatments are available, it will remain unclear whether more such treatments should be undertaken.
More detailed information on experimental lake-wide treatments of curly-leaf pondweed may be obtained by reading the chapter on curly-leaf pondweed in the DNR’s annual report on invasive species. Alternatively, please call the DNR’s Division of Ecological Services at 651-296-2835 or 888-MINNDNR to request a copy of this report or to discuss options for control of curly-leaf pondweed.
Photo of Curly-leaf Pondweed
Photo by Vic Ramey, University of Florida
Three areas approved by the DNR and treated with by PLM with Aquathol on May 22, 2008.
From left to right, the sizes of the treatment areas are 35.7, 10.8 and 13 acres.
Aquathol® and Hydrothol® Aquatic Herbicides and Algicides Safety Information
What about swimming after an application?
There is no swimming restriction on any of the Endothall labels. These products dissipate rapidly after use. They are poorly absorbed through the skin and small amounts of water that are ingested while swimming are not considered toxic or harmful. An adult would have to continuously swim more than 500 hours (20 days) to absorb and ingest more than enough Endothall to exceed the No Observable Effect Level (NOEL*). That’s enough time to swim 10 laps across Lake Michigan.
Can I eat the fish from the treated lake?
Eating fish following an Endothall treatment is not prohibited. Endothall does not concentrate in fish. A person would have to eat over 600 lbs. of fish from water treated with Aquathol or Hydrothol every day for a lifetime to exceed the NOEL.
What about livestock that drink treated water?
Like fish, Endothall is not concentrated in the meat and is excreted rapidly. Beef cattle drinking from a pond treated with Aquathol or Hydrothol would ingest a small quantity of Endothall. A person would have to eat almost 1300 lbs. of meat from animals drinking only treated water to exceed the NOEL.
What if my dog or cat drinks the treated water?
This is considered incidental exposure. In addition Endothall is not toxic to dogs or cats at rates used to treat aquatic weeds and algae.
Is Endothall toxic to waterfowl or other wildlife?
Endothall formulations for aquatic uses are not toxic to waterfowl and wildlife when applied at labeled rates. (The maximum rate of application is 5 ppm for any of the Endothall products: the 8-day LC50 for bobwhite quail and mallard ducklings is >5,000 ppm and the 21-day LD50 for mallard ducks is 344 ppm.)
How long does Endothall last in the water following a treatment?
The time that Endothall remains in the water varies with the size and type of application made, but it generally dissipates and degrades within a few days. The half-life (time in which 1/2 of the product is degraded) is about 3-7 days in most situations. Endothall is degraded by microbes into Carbon, Hydrogen, Oxygen and Organic Acids normally found in the environment.
What about drinking treated water?
The U.S. EPA has established a Maximum Contaminant Level (MCL) for drinking water of 0.1 ppm. An adult would have to drink more than 350 gallons of water ever day at the MCL of 0.1 ppm for a lifetime to exceed the NOEL
Aquatic plants play an important role in the ecology of our lakes and reservoirs. However, exotic invasive aquatic weeds such as Hydrilla, Eurasian Watermilfoil, Curlyleaf Pondweed and Water Hyacinth, along with noxious algae, often pose a serious threat to the health and well-being of these water resources. Endothall, the active ingredient in Aquathol and Hydrothol can enhance the aquatic environment and protect our waters by controlling these weeds and algae.
The following illustrates how levels of Aquathol and Hydrothol found in water following an application for control of aquatic weeds and algae, relate to human health.
The above statements are based on exposure or consumption of endothall by an adult at the EPA established and proposed tolerances or levels predicted from animal studies. To protect yourself and the environment when using pesticides, carefully read and follow label directions.
*The NOEL is the highest dose at which no adverse effects were observed in laboratory animals. For regulatory purposes, the NOEL is selected from the laboratory mammalian species that shows the greatest sensitivity to the effects of the pesticide.
Aquathol® is a registered trademark of United Phosphorus, Inc.
© 2007 United Phosphorus, Inc.
All rights reserved.
Delineation – DNR – June 2008
This delineation shows the areas of curly-leaf on Fish Trap Lake approximately one month after Professional Lake Management treated the lake. The only area not depicted is the area where Thoroughfare Creek enters the lake. Based on a previous estimate, there is about 15 acres in that area.