Aquatic Plant Survey

RMB Environmental Laboratories, Inc. conducted an aquatic plant survey of East Battle Lake during August 2019.

East Battle Lake Plant Survey Comparison

2013 – 2019

Overall, there was a lot of similarity between the two surveys. There was a very similar composition of native plants found in both surveys. Each survey found the following native plants: chara, bladderwort, coontail, northern milfoil, Illinois pondweed, variable pondweed, sago pondweed, variable leaf pondweed, water celery, marigold, white stem pondweed, clasping leaf pondweed, and Canadian waterweed. Both surveys also saw the same three most abundant plants of chara, common bladderwort, and coontail. Furthermore, they appeared to generally be in the same areas.

It does appear that chara was more spread throughout the northeast bay of the lake. That portion of the lake is heavily vegetated; however, it appears to have become less diverse. In 2013 there was up to 10 species found in the bay, and in 2019 the maximum number found in that bay was five. That could be due to the fact that the chara overcrowded some other native vegetation. Additionally, the bay is covered with lily pads, which could also shade out plants.

Coontail was also found in the same general areas around the lake in 2019 as 2013. It was scattered in the northeast bay in each survey, and more prevalent in the south basin, especially in the narrows leading into the north basin. Coontail was found in deeper areas in both surveys as well between 9 – 12 ft.

Bladderwort again was found in very similar areas in both surveys. It appears to have become denser in 2019 from 2013 in the northeast bay. This is likely because bladderwort does not anchor with roots in the sediment, so it can exist with chara and other rooted plants found in that area.

The survey in 2019 indicated no drastic or alarming changes in the vegetation composition from 2013. Many of the same native plant species were found in each survey, and no invasive species were found in 2019. I would suggest that the EBLWA continue to monitor the plant community of East Battle Lake every few years to track changes or shifts in the lake. Furthermore, East Battle Lake is at risk to infestation due to its location in Otter Tail County with other lakes infested with invasive plants.

The complete survey is attached.

Freshwater Scientific Services, LLC (fixmylake.com) conducted an aquatic plant survey of East Battle Lake during the summer of 2012.

Summary of Findings

1. We found no submersed aquatic invasive plants in the lake in 2012 (no curlyleaf pondweed, Eurasian watermilfoil, or flowering rush).

2. Invasive purple loosestrife was found growing on the shore of East Battle Lake in a few localized areas, but we found no large stands of loosestrife in 2012.

3. East Battle Lake currently supports an abundant and diverse plant community (26 species; 19 submersed, 3 floating-leaf, and 4 emergent) with most areas shallower than 20 feet supporting plant growth. The plant community was dominated by muskgrass (Chara spp.; ~ 80% occurrence), which formed large, dense beds throughout much of the lake. In addition, several other taxa were found at more than 20% of the sampled locations (≤15 ft), including common bladderwort, coontail, northern watermilfoil, and illinois pondweed.

4. Recreational impairment due to plant growth was generally limited to the large, shallow bay on the far northeastern shore of the lake. Plants throughout most of this area grew to within 1 foot of the surface and formed an extensive area of dense surface growth that impaired boating and water recreation. Despite the observed areas of dense plant growth, 90 to 95% of the lake experienced no impairment of recreation or navigation due to plants.

The complete survey report is attached.