Invasive weed found in Medicine Lake

Recently, a watercraft inspector discovered starry stonewort, an invasive weed species, in Medicine Lake. Since showing up in Minnesota in 2015, there have been a variety of attempts to control/remove the aquatic invader. Medicine Lake is one of the neighboring lakes to Lake Minnetonka which has raised some concerns within the community as to if the Invasive species will show in lake Minnetonka. As of 2018, “starry stonewort has not yet been eradicated from any U.S. lake” (Marohn, para. 12).

What is starry stonewort?

Starry stonewort is a bright green, bushy algae that is native to Eurasia. It has very small white, star-shaped bulbils that form on clear threads at the base of the plant. The invasive weed is usually found at or below the sediment surface, making it even more difficult to remove. Starry stonewort can be mistaken as many other beneficial, grass-like algae such as chara and the other species of stonewort.

Weed found in Medicine Lake

How you can help?

According to the Minnesota DNR law, it requires water recreationist to:

  1. Clean all aquatic plants from your watercraft.
  2. Drain all the water from your watercraft by pulling the plug and keeping them out during transportation.
  3. Dispose of all the unwanted bait into the trash.
  4. Dry lifts, docks, boats, or any other watercraft equipment for a minimum of 21 days before putting it into another lake.

What we are doing to help control starry stonewort:

We have found that the best way to help control starry stonewort and other forms of invasive weed species from spreading across our Minnesota lakes, is by utilizing watercraft inspections at boat launches. More about our watercraft inspection services can be found here: If your lake identifies an infestation early on we provide manual SCUBA hand removal of the biomass.  For more developed patches we are also able to provide Diver assisted suction harvesting (DASH).

For more information about starry stonewort check out the links below.