Hello LSC, we'd like to let you know about the LSCA's 2024 plans for our Milfoil Control Program.

On April 26th, LSCA Trustees, our Diver Assisted Suction Harvesting (DASH) team, our contractor, and Arrowwood Environmental performed a spring survey of the lake for milfoil growth.

Our findings were similar to those seen in the fall 2023 Aquatic Plant Survey, which you can view here. Using the information gathered from both surveys, we have created a map to show where spot treatments will take place, and where our DASH team will be working this season:

Spot treatments of ProcellaCOR EC will take place on Tuesday, June 4th. Please see the attached notice below for further information:

Our DASH team will begin swimming through low density milfoil areas to hand-pull in June when the water temp allows, and will begin full DASH operations on July 1st.

The LSCA’s Milfoil Control Program consists of five components:

1. ‘Stop The Spread’ education and outreach. Our ‘Stop The Spread’ campaign educates boaters and property owners on best practices to limit the spread of milfoil. Each year, the LSCA holds a lake community meeting to discuss the control plan for the season, answer questions, and hand out a flyer with best practices for lake users to limit the spread of milfoil.

2. Volunteer milfoil cleanup. Throughout the season, we organize volunteers to collect detached floating milfoil from the lake and deposit it on our designated drop off platforms. The milfoil is then picked up from the platforms and disposed of. We also encourage boaters and property owners to remove any milfoil they see in the lake while boating or on their shoreline.

3. DASH - Diver Assisted Suction Harvesting. Our DASH crew suits up in scuba gear and hand-pulls milfoil by the roots from the lakebed. In sections of lower milfoil density, they will swim the area and hand-pull with mesh bags. In higher density areas, they will set up the DASH equipment which allows them to suction the hand-pulled milfoil up through a tube to a catch table on a boat. Milfoil is then placed in 17.5 gallon buckets for transport off the lake.

4. Herbicide spot treatments with ProcellaCOR EC. In order to maximize our DASH crew’s time, effectiveness, and number of acres covered, one of our control methods includes spot treatments with the herbicide ProcellaCOR EC.

5. Water quality improvement programs. Although not directly related to Milfoil Control, the LSCA's work on Lake Wise on LSC, the LSC Stormwater Master Plan, and the LSC Watershed Action Plan all help to limit phosphorus and other nutrients from entering the lake which can contribute to excessive plant growth, and improves overall water quality.

These efforts have resulted in the lowest percentage of milfoil cover and frequency of occurrence in the lake since the mid-2000s. Also, and just as importantly, we have seen many species of our native aquatic plants that have been suppressed by milfoil growth like Water stargrass, Tape grass, Thin-leaf pondweed, Illinois pondweed, Common waterweed, and Robbins’ pondweed have all increased in frequency of occurrence. These results are exactly what we want to see!

Lake St. Catherine has over 30 native aquatic plants which are important and necessary to sustain a healthy lake ecology. Our efforts are focused on reducing the amount of milfoil in the lake so that these native aquatic plants can grow as they normally would. Keeping milfoil under control is helping to return the aquatic plant environment to conditions before milfoil was introduced in the 1970s. Because of our milfoil control efforts, we again have a complex and diverse native aquatic plant community.

What can you do to help?

• As a general rule, get as much milfoil out of the lake as possible and dispose of it.

• Don’t drive through milfoil patches with your boat which will create fragments.

• If you have milfoil on your prop, don’t just reverse and drive away, please remove it from the lake.

• If you have milfoil growing in your dock or swimming area, pull it out by the roots and remove it from the lake.

• If you see milfoil floating anywhere in the lake, near your dock, or along your shoreline, remove it from the lake.

• Become a member of the LSCA to help support our efforts!

Keep in mind that native aquatic plants are important and necessary to sustain a healthy lake ecology. Please focus on removing milfoil plants only. It's up to all of us to stop the spread of milfoil.

We’re also working to schedule our yearly Milfoil Control Meeting - which we’ll announce soon. All are welcome to attend to learn about our milfoil control plans for the season, and ask questions. Also, as we have done the past several years, a drop-off float is located in the Channel where you can deposit detached milfoil and other plants - and we’ll remove them from the lake.

As you may be aware, there has been a lot of recent misinformation about milfoil, ProcellaCOR, the permitting process, and Lake St. Catherine in general. We encourage everyone to visit our newly updated Milfoil Control Program page to read more about this important topic.

The LSCA has always employed evidenced-based decision making when evaluating lake related issues, and we continue to do so with our Milfoil Control Program. Working with the State and lake scientists & experts, following the science and the data, and evaluating the results of our efforts show that we are doing the right things for the long-term health of LSC. To our members, and all who love LSC, if you ever have any questions or concerns, reach out to us, we’d be happy to answer them. You can always reach us at info@lakestcatherine.org.

Thank you.