Berry Lake Community District forms to tame invasive plants

NORTHEAST WIS. – When the sun sets on Berry Lake in northeast Wisconsin, its brilliance reflects on the water, painting a picture of nature in all its colorful glory.

The lake is the drawing card for residents like 65-year-old Tonni Larson and her family from the Bay of Green Bay.

“It’s peaceful, and it’s clean, and it’s a nice size,” she said about Berry Lake, a 210-acre lake in Oconto and Menominee counties. 

For 10 years, the Larsons have enjoyed Berry Lake, but not the Eurasian water milfoil that invaded it.

If uncontrolled, the invasive species can crowd out native plants and upset the lake’s ecosystem. Eurasian water milfoil is an aquatic plant with long, stringy branches that get caught in boat motors and break propeller blades. The species has cropped up in many, if not most, lakes in Wisconsin, experts said. It’s thought to travel from one lake to another by boat if boaters aren’t careful about cleaning their boat wells when they leave a lake with milfoil.

In its densest spots in inland lakes, the milfoil are a drag on boating. When a boat gets caught in the milfoil, “You have to pick it off because your boat starts to vibrate,” Larson said.

But two weeks after chemical treatments were applied, the lake is largely free of milfoil, thanks to the efforts of a core group of residents devoted to keeping the lake as pristine as possible. “We have a very clear, nice lake. That’s why we want to keep it that way,” said Larson, commission treasurer for the newly organized Berry Lake Community District in the Town of Underhill.

The district became official Jan. 1, allowing landowners around the 210-acre lake to be taxed locally for lake maintenance costs and making the community eligible for state grants and other funding. It exists to address “issues that threaten the lake’s ecosystem, protect the beauty and use of the lake and to maintain property values,” according to its website.

With a public boat landing, campground and a Lutheran church camp situated on its shores, Berry Lake has a public purpose and needed a way to access public funds, Larson said. An association alone didn’t have authority to impose a millage or per-parcel fee, Larson said.

But some association members opposed forming a district. “They think it’s government, and it’s government that gets involved in every decision you make; it’s not a good thing,” Larson said, recalling what she had to overcome to win support for the district.

Informal networking was influential. While volunteering at a charity event, Larson met a woman from another lake who touted the financial advantages of forming a district.

After applying for a state grant last year to treat the milfoil in Berry Lake and getting rejected, Larson said, “We thought, what are we going to do? We didn’t get the grant. The milfoil was growing. The water was going down.”

Larson contacted Oconto County Conservationist Ken Dolata and Steve Heimerman, a board member of Oconto County Lakes and Waterways Association. She also called existing lake districts. The more research Larson did, the more determined she was to organize a lake district to more evenly spread the costs of treating and preserving the lake. It would make Berry Lake eligible for more public grants and give it taxation authority. “We said [that] we just have to do it. We were up against a brick wall,” she said.

With the value of lake property at stake, the benefits of forming a district outweighed any perceived disadvantages, Larson said. It took five months of organizing and networking to obtain signatures from 58% of property owners, more than the required 51%, she said. “I went door to door over Labor Day weekend. Only one person was negative,” Larson said.

At an Aug. 23 annual meeting to be held at the Town of Underhill’s community center, district members will vote silently on three commissioners, the budget and whether they want a mill rate or per-parcel fee imposed. “On our side of the water, they all seem to favor the mill rate,” Larson said.

For a 15-acre parcel of forested vacant land across the road from the lake, the expected lake-maintenance cost to the property owner would be $34.76, Larson said.

“The members all have a voice. They all help and contribute to the expense of the lake to keep it in good shape, and they benefit from it,” she said.

Of the district’s 159 parcels, 130 are on the lake, but many people own several parcels. About 18 lake-property owners are full-time residents, and the rest are seasonal residents, she said. Living on or near a lake means joining a community, she said. “Everyone is interested in maintaining and taking care of it. It’s a good place to be,” Larson said. 

Preserving the lake drove Larson’s efforts to stamp out the milfoil. This year, Berry Lake received a two-year surface water grant from the Department of Natural Resources with expected total costs of $87,000, though the actual costs could be lower, Larson said. The DNR expects the local district to contribute 25% of the costs, though other funds can offset this amount. Berry Lake received an Oconto County “healthy water” grant of 10% or about $6,880, she said.

“The cost of a June 10 chemical treatment on Berry Lake cost about $43,000, but monitoring to test whether the milfoil is rebounding will cost extra,” Larson explained. “We have money yet to use next year to do Diver Assistance Suction Harvesting, or DASH, where divers will come in and pull it from the root and suction it to a boat and take it away,” she said.

“Managing the invasives is a year-round job with studies, pre- and post-treatment surveys, lining up vendors to do the treatment and working with the state and county to write grants”, said Steve Heimerman, who sits on the Berry Lake Community District board as commissioner representative for the Town of Underhill. The Town contributed $5,000 toward the treatment cost, he said.

To be eligible for grants for chemical treatments, districts are expected to have a five-year aquatic invasive plants report with a price tag of about $18,000, Larson said.

Berry Lake had four large areas in need of treatment, including one that was 10 acres in size, Larson said.

The district’s officers plan to monitor the lake for signs of a resurgence. Aquatic Plant Management LLC applied a chemical treatment on June 10 from a boat equipped with hoses that would take the herbicide down to the bottom of lake, closer to the milfoil’s roots, Larson said.

The herbicide ProcellaCOR wipes out Eurasian water milfoil without affecting most native species. It’s safe for humans and fish to use the water, but residents are warned not to irrigate using the lake water for a period of time. 

After the treatment comes the follow-up monitoring. Larson and her husband and another couple obtained water samples from the four areas where the milfoil was treated. Water samples were taken three hours after the treatment and at nine and 24 hours following the treatment.  They also obtained samples on the third, ninth and 12th days following the treatment, Larson said.

On the 70th day following the treatment, the samples will be sent to a lab in Madison for testing to see how effective the treatment of ProcellaCOR was.

For Larson, stepping up to maintain the lake has involved a new education. “It’s very interesting. I’m learning more all the time about anything we can do to keep the ecosystem healthy.”