Aquatic Plant Management
One of the primary responsibilities of SAWM is to monitor and manage the aquatic plants within the Shawano waterways. A healthy native aquatic plant environment is a critical element in any healthy aquatic ecosystem, providing food and habitat to wildlife, improving water quality and stabilizing bottom sediments. Our excellent fishery and water clarity is a testament to the healthy and diverse native aquatic plant environment of Shawano Lake.
Unfortunately, aquatic invasive plants, especially Eurasian water milfoil (EWM) and curly-leaf pondweed (CLP), are also found in our waters. SAWM has been active in monitoring the waters for invasive species and, in 2013 contracted with Onterra LLC, an environmental engineering firm, to survey Shawano Lake and document the location and density of EWM and CP during the summer and fall of 2013. The resulting report, Shawano Lake AIS Control and Prevention Project–Phase 1: Trial EWM Treatment, dated February 1, 2014, reported on the process and results of the survey. The report was the basis for developing an aquatic invasive species management plan and can be accessed from the drop-down menu at the bottom of this page.
The Aquatic Plant Management Plan Update report dated April 2014, developed by Onterra LLC based on their 2013 plant survey, is SAWM’s roadmap for managing EWM found in Shawano Lake. This report is also available in the drop-down menu below. The initial phase of the plan called for a trial treatment of about 145 acres of dense EWM located on the west end of Shawano Lake. Approval of the trial treatment and a grant to cover a majority of the cost was obtained from the Wisconsin DNR. A copy of the Aquatic Plant Control Permit and a chemical fact sheet are accessible below. The chemical treatment was applied in spring 2014. The results were monitored immediately following the treatment and throughout the summer and fall of 2014.
The report documenting the results of the 2014 phase I trial treatment indicate that the treatment was very successful. The Onterra report is available below. Throughout 2015 Onterra continued to monitor the trial treatment area to complete the assessment of the 2014 EWM treatment. The trial treatment area did not have any significant reappearance of EWM in 2015 so the large scale treatment plans moved forward. Part of the process included surveying over 900 riparian property owners on Shawano Lake to gauge their level of support for the treatment. Almost 60% of the surveys were returned and the response overwhelmingly supported a 2016 treatment.
On February 1, 2016, an application for a $200,000 grant from the Wisconsin DNR was submitted and on April 1 SAWM was notified that our grant was approved. The treatment was done on May 23rd and 24th. A map of the area that was treated as well as the permit authorizing the treatment is available below. Post-treatment assessments were done in 2016, 2017, 2018, 2019 and will continue in future years. A report assessing the 2016 treatment results is below.