New Infestations

Le Sueur County has set aside AIS Prevention Aid funds for new infestations/introductions of Aquatic Invasive Species that are found within the County.  Early detection and management is crucial to minimize the spread and impacts of the new infestation/introduction within a body of water and to surrounding bodies of water.

Recently, Le Sueur County has utilized AIS funds to address new infestations of Eurasian Watermilfoil in Lake Tetonka and Lake Francis.

Lake Tetonka

2017 Lake Tetonka EWM Assessment Report

Lake Francis

2018 Lake Francis EWM Removal and Survey Report

2017 Lake Francis EWM Removal and Survey Report



The picture above is Flowering Rush (photo credit: Minnesota Wildflowers Website).  This species has been found along the shoreline of three lakes within Le Sueur County.  It is best to identify this species when flowering due to its resemblance to other aquatic species.

The picture to the left is Eurasian Watermilfoil (EWM) that was removed from Lake Francis in the fall of 2018.  This was a continued effort to control an EWM infestation that began in 2017.  Hand removal was selected due to the healthy population of native aquatic vegetation that resides in Lake Francis.

Eurasian Watermilfoil in Upper Sakatah Lake

Eurasian Watermilfoil was detected in Upper Sakatah Lake in the summer of 2020.  The presence of Eurasian Watermilfoil was located on the south side of the lake, in sparse patches, and found in shallow water.  Le Sueur County informed neighboring counties and soil and water conservations districts, lake associations, and watercraft inspectors of the new infestation.  Additionally, an article was posted in the local paper.  

Le Sueur County partnered with the Waterville Lakes Association and the Minnesota DNR to treat the Eurasian Watermilfoil that was present.  The treatment was completed on September 22, 2020.  A chemical treatment was used, specifically 2,4-D Anime.  Upper Sakatah Lake will be surveyed in 2021 to see how the chemical treatment worked, and if additional treatment methods are needed. 

New Infestation EWM Upper Sakatah Lake