Approval letter

This Aquatic Plant Management Plan for Deer Lake presents a strategy for managing aquatic plants by protecting native plant populations, managing curly leaf pondweed, and preventing establishment of invasive species through the year 2021. The plan also covers a response to zebra mussels, an aquatic invader found in the lake in late 2016. The plan includes data about the plant community, watershed, and water quality of the lake. It also reviews a history of aquatic plant management on Deer Lake.

In April, June and July of 2016 a point intercept aquatic macrophyte survey was conducted on Deer Lake in Polk County Wisconsin. The spring survey was to evaluate the presence of Potamogeton crispus-curly leaf pondweed (CLP). CLP was sampled in six locations of the sample grid and located in numerous other locations outside of the grid. The later season survey in July found 31 species of native plant sampled. Four species of invasive species were observed but not sampled. The Simpson’s diversity index was 0.90. The maximum depth of plants was 26.2 feet and the mean depth of plants was 10.7 feet. 87.8% of the defined littoral zone had aquatic plants present. The floristic quality index was 33.8 which is much higher than the ecoregion median of other lakes. Compared to a 2010 aquatic macrophyte survey, there was a statistically significant increase in four native species and a significant decrease in three native species. The floristic quality index was slightly higher in 2016. All other parameters were similar in both surveys.

Grant AEPP46216 awarded