Eurasian Watermilfoil & Curly-leaf pondweed

Eurasian Watermilfoil and Curly-leaf pondweed are invasive aquatic plants that form dense, floating mats of vegetation.  These mats are a nuisance to many outdoor enthusiasts including boaters, swimmers, and fishermen.  They also out compete native plants because these floating mats crowd them out.  Curly-leaf pondweed also starts growing earlier than most native plants.  This gives it an advantage over native plants because it consumes nutrients before the natives start growing.  Learn more about Eurasian Watermilfoil in this aquatic invasive species fact sheet. See what the plant looks like with this identification card.  Learn more about Curly-leaf pondweed in this aquatic invasive species fact sheet and at the DNR Curly-leaf pondweed webpage.

Infested lakes in Scott County

Click on each tab to view the list of waterbodies are infested with each plant.  For your convenience, the waterbodies are listed by their respective watershed authority.  
  1. Eurasian Watermilfoil
  2. Curly-leaf pondweed

Scott Watershed Management Organization's lakes infested with Eurasian Watermilfoil:

  • McMahon (Carl's) Lake
  • O’Dowd Lake 
  • Thole Lake
  • McColl Pond
Scott County staff survey the following lakes at least yearly to manage Eurasian Watermilfoil and Curly-leaf Pondweed.  See SWMO's latest annual report for more information on SWMO invasive species management.

Prior Lake Spring Lake Watershed District's (PLSLWD) lakes infested with Eurasian Watermilfoil:

  • Cate's (Hidden) Lake
  • Lower Prior Lake
  • Upper Prior Lake
  • Pike Lake
See PLSLWD's Lake Monitoring webpage for more information about lake surveying and treatment in their jurisdiction.

Find out more about these lakes at DNR's Lakefinder webpage.

How do Eurasian Watermilfoil and Curly-leaf pondweed spread?

They are very easily spread because it only takes a small piece of the plant carried into a new waterbody.  They often get caught on watercraft and boat trailers, which is probably the most common way they are spread.  Learn more about how Eurasian Watermilfoil is spread by visiting DNR's webpage.  Learn more about how Curly-leaf pondweed is spread by visiting the Minnesota Sea Grant Curly-leaf Pondweed webpage.

What can we do to prevent spreading aquatic invasive

We can all prevent the spread of these and other prolific plants by following DNR's Clean, Drain, Dry instructional video on YouTube.  This short brochure summarizes what to do to avoid the biggest concern species.  Clean In Clean Out training is available on the DNR training webpage.  DNR's What You Can Do webpage has more information available to prevent the spread of these and other aquatic invasive species (AIS).  Grants may be available to help local governments with aquatic invasive species management

What do I do if I find aquatic invasive plants in a lake where they haven't been found before?

Contact the DNR.  Call 1-651-259-5100, and ask to speak to an Aquatic Invasive Species (AIS) Specialist.  

How do I know which invasive plants have been documented in the lake?

Go to DNR's Lakefinder page.  Search for the lake in question.  The lake information will include known aquatic invasive species.

Click on the pictures for more information

Eurasian Watermilfoil
Curlyleaf Pondweed
Scott County Aquatic Plant Surveys