Frequently Asked Questions

---

Simply put, all of us use the entire bay and we bring the invasives back into our area.  Like dandelions, if you neighbor doesn't treat then we will continue to have to do our individual treatments each year.  This program is designed to decrease the amount of invasives that need to be treated every year with the goal being that you personally will not need to have your lakeshore treated for these invasive weeds.  Does it mean that all the weeds will be gone? NO!  Aquatic vegetation is needed to keep our bay healthy.  We will only be treating the invasive, non-native weeds.  

With our plan for the fall milfoil treatment it is anticipated that less then 20% of the milfoil will return in the 2nd year which will significantly reduce our cost to treat our bay in year 2.

We pay a lot of taxes to be on Lake Minnetonka and it is frustrating to have to foot the bill for bay AIS treatments.  What we have found is that if we don't advocate for our bay then no one is concerned about our weeds or our water quality.  We have begun conversations with the City of Mound, the Minnehaha Creek Watershed, the DNR and the Lake Minnetonka Conservation District to determine ways to tap into state, county and city funds.  The goal of establishing a bay association is to be in front of these organization and to draw on our state representatives to help us to protect our bay and all of Lake Minnetonka.

For this years treatment we will be applying for grants through the DNR and the LMCD to help offset some of the cost.  If we have dollars left from our fundraising it will roll into 2023 treatment.

No.  A weed free bay is a dead bay.  Native plants are an important part of a healthy lake's ecosytems.  Currently the Lake Minnetonka's Bay Treatment Program specifically targets non-native, invasive Eurasian watermilfoil,  Curly Leaf Pondweed and flowering rush.  These non-native weeds make recreation and boating difficult and are harmful to fish habitat and aquatic life.

 Once established, invasive weeds  are hard to control. Generally, after the first few years of treatment, the acreage needed to be  treated decreases significantly. Most invasive weeds reproduce from fragments, so boaters and  water currents can spread weeds from bay to bay. Annual weed surveys and spot treatments will  be needed to prevent large weed beds from reestablishing. 

 Only herbicides approved as safe by  the US Environmental Protection Agency and the MnDNR are used by the Lake Minnetonka  Association. Herbicides are applied at or below the recommended rates. Herbicides containing  glyphosates are not used. The Lake Minnetonka Association hires only trained and licensed  applicators for its Bay Treatments. 

Our applicators use state of the art equipment and application methods to pinpoint exactly where  to treat and what amount of herbicide to use. This way, we save money, use less herbicide, treat  only the areas necessary, and get better results. Our applicators work closely with the University  of Minnesota and other researchers to continually improve the bay treatments.  

 There are no fishing restrictions following bay  treatments. The herbicides used do not accumulate in fish.  

The bay treatments are restoring native plants.  Bays enrolled in the Bay Treatment Program are seeing an increase in the diversity and density of  native plants. Research shows that healthy native plant populations can prevent new, non-native  invasive weeds from becoming established and can help to improve fisheries and habitat for  aquatic species.  

 It is generally recommended  not to swim for 24 hours after treatment. While almost all of the herbicides used on Lake  Minnetonka do not have a swimming restriction, the state of Minnesota requires a notice be posted the day of treatment in areas treated within 100 feet from shore. Therefore, if your  property does not have a notice (sign in the yard) you do not have a swimming restriction. Also,  offshore areas of the lake (deeper water) will be safe for swimming and boating after treatment. 

It depends  on the treatment. Some of the herbicides used may have turf and ornamental flower irrigation  restrictions. The restrictions can range from 3 days to 14 days. If you use water from the lake to  irrigate, please read posted signs carefully to determine your irrigation restrictions after a treatment. It is also recommended that homeowner turn off weed blowers for 24 hours following treatments. 

 Bay treatments are more cost effective than weed cutting. Research  shows that cutting weeds can increase the rate of growth and the density of invasive plants such as  Eurasian watermilfoil and flowering rush. Furthermore, cutting weeds increases the risk of  spreading new invasive weeds lakewide. 

The applicator we are using has a contract with the Lake Minnetonka Association and is highly recommended by the DNR.  The company is PLM Lake & Land Management.  Per their permit communication to the DNR, they indicated that treatment will depend on what vegetation is found on the spring delineation survey.  They propose using diquat for areas with just Curly Leaf pondweed and Diquat/Procellacor combination for areas where milfoil is present.

Diquat Dibromide Screening Profile: https://www.health.state.mn.us/communities/environment/risk/docs/guidance/dwec/screening/diquatdibromide.pdf

Diquat Fact Sheet: https://dnr.wi.gov/water/wsSWIMSDocument.ashx?documentSeqNo=158277108

• Treatment of the Curly leaf pondweed is done early in the spring when bay oxygen levels are higher
• The plant is smaller so there is less plant material to decompose
• The decomp rate of the plant material is slower when the water is cold
• In the current situation, the CLP can grow to 15 feet tall and then dies off in the warm water around early July leaving more material to be decomposed at the height of water temperatures.