Beecher Lake volunteers tackle invasive species year-round

MARINETTE COUNTY – Discovering what doesn’t work can be a giant leap toward progress in controlling invasive species, just ask Erin Enk and Nancy McKenney of Beecher Lake.

As residents of the 56-acre lake in Marinette County, they’ve grappled with a persistent underwater invasive weed called Eurasian water milfoil. This summer, they’re encouraged by signs their year-round efforts to confront the issue finally seem to be paying off.

But, it hasn’t been a straight path forward.

“It’s a journey,” McKenney said, describing about two decades’ of volunteer work spent trying to control Eurasian water milfoil, an invasive species that could put the lake’s natural ecosystem at risk if left uncontrolled.

Her daughter Erin Enk, 37, has joined in the effort to preserve the lake, which she enjoys for its beauty and biodiversity. They want to maintain the lake for future generations.

“We’ve been able to do this for 20 years now,” said Enk, a Stevens Point artist and jewelry maker who holds a master’s degree in biological science. “Even though we’ve had the milfoil present for this long, we were able to keep it low and our biodiversity is still very strong,” she said.

Enk said she first became interested in studying the outdoors from spending summers with her grandparents at Beecher Lake. “I’ve been going up there my whole life,” said Enk.

Several hundred residents, including 69 property owners, are members of the lake’s community district, with some owning more than one parcel, McKenney said. With a public boat ramp, beach and dam, the lake formed a community lake district decades ago, making it eligible for state environmental grants and allowing it to include a separate water maintenance fee on property owners’ tax bills. The fee was about $200 per parcel in 2024, McKenney said.

Beecher Lake residents first reported Eurasian water milfoil in 2007, Enk said. In 2010, they received a $30,000 Aquatic Invasive Species control grant and in 2015, they received a $192,000 grant to control the water milfoil. As a condition of the Department of Natural Resources grants, the local district provided 25% matches, Enk said.

Based on the 2023 annual aquatic plant surveys Marinette County Water Specialist Chuck Druckrey conducted on Beecher and Upper Lakes, the Eurasian water milfoil was found at 75% of 192 points in water less than 12 feet deep, according to public documents from Beecher Lake’s 2024 Annual Meeting. In 2024, following a May application of ProcellaCor, a plant survey found zero Eurasian water milfoil at any of the points, McKenney said. But, it’s taken a long time to find an effective way to control the milfoil.

The ProcellaCor, a relatively new herbicide first used in 2017, seems to have knocked out most of the milfoil, but whether it’s wiped out for good or will rise again isn’t yet clear, Enk said.

A group of four volunteers on a committee leads Beecher Lake’s aquatic species control efforts. Over the years, about 20 people have cycled through the committee, including Enk’s mother who served as chairperson for quite a while. McKenney has also served as the secretary of the Beecher and Upper Lakes Public Inland Lake Protection and Rehabilitation District Board of Commissioners
“We’ve had successes and failures from year to year,” Enk said. “It’s been a huge group effort.”

Beecher Lake worked with Druckrey to apply for an $8,500 Surface Water Planning Grant it received last year from the Wisconsin Department of Natural Resources, Enk said. Two prior grants netted $222,000, with a 25% match from the lake district.

Applying the chemical treatment of 2,4 D would knock down the water milfoil count, but it bounced back. “Within the same growing area, it would rebound to the next level. We were noticing [the herbicide 2,4 D] wasn’t really super effective,” said Enk.

Last year, samples of water milfoil collected from the lake were sent to the University of Montana, where scientists determined the unusual milfoil variety was resistant to the herbicide it was using, called 2,4D, Enk said.

“It’s important we didn’t keep using 2,4D if it isn’t effective,” Enk said, as it could affect other aquatic life.

What the pair has learned along the way they’ve shared with other lake districts, McKenney said. “It’s comparing the science as you get it. That’s a benefit to everybody, not just property owners. We have people fishing and paddleboarding. We have other districts that benefit from the knowledge that’s gained through this grant process,” she said.

The first tactic Beecher Lake residents tried over 15 years ago involved mechanical harvesting, a process designed to rid the lake water of the milfoil, McKenney said. After several years, residents realized it wasn’t controlling the milfoil and could have been spreading it.

Next, they tried treating Eurasian water milfoil with 2,4D several times only to watch as the audacious aquatic species rose again. A partial lake treatment of 14.6 acres was conducted in 2008, followed by a 5.8 acre treatment in 2010 and whole-lake treatments in 2013 and 2014, Enk said.

With limited success, a Beecher Lake Committee decided to take advantage of the winter months to kill the water milfoil by exposing it to freezing temperatures. Volunteers installed valves in the dam to control the water level, drawing it down in the winter after native aquatic life hibernated.

“The draw down after the changes to the dam in the winter of 2017-18 was successful and reduced Eurasian water milfoil occurrence from 45% to just 5%,” she said. “The results were not long lasting, however, and were back up to pre-treatment levels within three years.”

Snow coverage in 2022-23 prevented a successful freeze and meant a draw down that year wasn’t successful. The following summer, the invasive species was found in about 75% of the lake, Enk said.

To obtain an estimate of how much milfoil is in the lake, Marinette County Water Quality Specialist Druckney has taken samples from the bottom of the lake and assigned them a ranking, such as 1, 2 or 3, depending on the plant quantity found, Enk said.

Samples are taken with a rake that scrapes the bottom of the lake for the plant. The volume of plants found on the rake’s head is recorded as an indication of the milfoil’s volume and density, Enk explained.

At the end of the summer, Enk said, another plant survey will reveal any changes to the ecosystem. A plan for maintaining the lake will be written, explaining what’s been done and what’s been effective.

The most effective strategy going forward is likely a combination of summer and winter techniques for controlling the invasive species.
“It’s labor intensive, but we’re all enjoying it,” McKenney said, sitting on her dock watching as Enk painted a landscape of the lake. “We’re so lucky to live where we do. We just have to preserve it.”