Lake Wawasee Aquatic Vegetation Management Plan 2009

Executive Summary
V3 was contracted by the Wawasee Area Conservancy Foundation (WACF) to update the 2006 Lake Wawasee Aquatic Vegetation Management Plan and include results of vegetation surveys in ecozone areas of Conklin and Johnson Bay. Native species provide many benefits which can be diminished by the presence of exotic aquatic vegetative species. The primary submersed aquatic exotic species at Lake Wawasee are Eurasian watermilfoil (Myriophyllum spicatum), curly leaf pond weed (Potamogeton crispus), and starry stonewort (Nitellopsis obtusa). In addition to disrupting the native vegetative community, exotic species inhibit recreational uses such as swimming, boating and fishing.

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Herbicide treatments are an effective management tool for controlling exotic species at Lake Wawasee. Aquatic Weed Control applied liquid 2,4-D (DMA®4 IVM) at a rate of 2.8 gal/A-ft.
to 25 acres of Eurasian watermilfoil on July 20, 2009 and treated an additional 25 acres on August 24, 2009. Aquatic Weed control applied liquid Nautique at a rate of 1.0 ppm to 15
acres of starry stonewort within Johnson Bay on August 31, 2009 (Figure 4). The treatment of starry stonewort was done later in the growth season when the star-shaped bulbils are developed
and allows for positive identification. V3 conducted the summer Tier II survey on August 12, 2009 to evaluate the vegetative community and determine the extent of exotic species in Lake Wawasee. The 2009 summer sampling effort had vegetation at 78 of the 100 sampling locations and collected a total of 16 species. The two exotic species collected were Eurasian watermilfoil and curlyleaf pondweed. Chara was the most frequently occurring species within Lake Wawasee (39%). Eurasian watermilfoil was present at 33% of sampling locations and collected from depths ranging from 4 to 23 feet during the 2009 Tier II survey. Curlyleaf pondweed was collected at one sampling location from a depth of 16 feet during the 2009 Tier II survey. Starry stonewort was collected at 4 sampling locations in Johnson Bay with a rake score frequency of 3 (20-100% rake teeth filled). Starry stonewort was collected from depths ranging from 3 to 5 feet (Figure 15).
In addition to the Tier II vegetation survey, V3 conducted ecozone surveys in Johnson Bay, Conklin Bay and North Bay. The ecozone survey of Johnson Bay was conducted on August 10, 2009.
Ecozone areas of Conklin Bay and North Bay were surveyed on August 11, 2009. The most common floating-leaf emergent species within Johnson and Conklin Bay are yellow pond lily
(Nuphar variegate) and white water lily (Nymphaea oderata). Fifteen emergent beds were mapped within Johnson Bay’s shoreline, which ranged from 0.01 – 2.74 acres in size and totaled
9.75 acres (Figure 13). The 2009 emergent survey results indicate that the buoys within Johnson Bay are protecting the ecozone areas, as emergent beds increased by 1 acre from 2008 to
2009. V3 mapped 9 beds along the shoreline of Conklin Bay. Conklin Bay’s emergent beds ranged from 0.09 – 3.44 acres in size and totaled 8.9 acres (Figure 14). Conklin Bay’s emergent
beds have increased by 0.93 acres since the 2008 emergent survey. Hardstem bulrush (Scirpus acutus), floating pondweed (Potamogeton natans) and white water lily composed the three
emergent clumps in North Bay in 2008 and 2009. North Bay’s clumps 1 and 3 expanded in 2009 and clump 2 decreased in size by 0.02 acres (Figure 17).

Eurasian watermilfoil has shown a steady increase in frequency from 2005 to 2009 (12.8% and 33% respectively) which substantiates the need for treatment in 2010. The 2005 survey effort
included more sampling locations in the shallow zones of Lake Wawasee which could have resulted in an underestimate of Eurasian watermilfoil’s abundance as it can thrive in deeper depth
zones. Locations where starry stonewort was retrieved in 2009 remained consistent with the locations starry stonewort was collected in 2008.

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For the health and safety of everyone, the WACF Board of Directors has cancelled the public meeting of the WACF *ANNUAL LAKE CELEBRATION & BRUNCH, *scheduled for Saturday, July 25th, 10:30 AM at the WACF Education Center.
In its place, the Board of Directors will attend the WACF ANNUAL MEETING, on Saturday, July 25, in-person, and socially-distanced, at the Ruddell Pavilion and the Jorgensen Amphitheater at the WACF Center. Board members and staff may also attend remotely.
The agenda for the Annual Meeting will include: a presentation by Dr. Jerry Sweeten, Ecosystems Connections Institute, on initial research and findings from the first year of the Wawasee Inlets Nutrient Study (WINS), the WACF Cattail Awards, recognizing exceptional commitment to the
enhancement of water quality in the Wawasee Area Watershed, and a salute to WACF volunteers.
Highlights of the Annual Meeting will be made available via remote
live-streaming or on the WACF YouTube Channel. Details on internet access of the meeting will be posted on and WACF Facebook page.


Key WACF Acquisition

After a full 20 years of negotiations with the property owner, WACF has acquired what is arguably their most important property. The Turkey Creek Inlet Preserve (across from Runaway Bay) filters the approximately 43% of water flowing into Lake Wawasee. Please take a few minutes to listen to Tom Yoder explain the importance of this property to Lake Wawasee.

New WACF Water Study

WACF is undertaking a new and comprehensive wetland water quality study that will allow us to focus our resources on the most critical hot spots. Read more….