Starry stonewort was first discovered in Minnesota waters in Lake Koronis in 2015. It’s now found in 19 Minnesota waterbodies. Lake Koronis is helping researchers understand how a changing climate may influence this invasive and how we can better manage it.
Overall, the research showed year-to-year variability in the total biomass of starry stonewort. There were good years and bad years for it. Warm summers adversely affected its total biomass, while warmer winters appear to have allowed it it to expand its coverage area, according to the research.
While warmer summer temperatures could reduce the total biomass, the area of a lake bottom covered by starry stonewort tended to increase in the summers that followed warmer winters. In this way, water winter temperatures could be associated with greater spread of starry stonewort.
Much more needs to be learned, but the data can help find the most effective methods for controlling the invasive plant. In many of the infected lakes, Koronis included, mechanical harvesting and herbicide applications are being used to manage it.