Fighting off an invading species can be an uphill battle. But a $13,500 grant from the Wisconsin Department of Natural Resources will help the Lake Hallie Lake Association make some headway in the war of attrition they’ve been waging against the hybrid watermilfoil weed.
First discovered in Lake Hallie in 2005, watermilfoil is an invasive aquatic plant that has an aggressive tendency to form a thick mat-like layer as it floats on the water. If left unchecked, this plant can cover huge areas of water, blocking sunlight from reaching more desirable plants and making boat traffic difficult.
“The milfoil has taken over the lake,” said George Wanserski, vice president of the Lake Association.
According to the DNR, watermilfoil is present in over 400 lakes statewde. It has also shown up in two other areas of Chippewa County, Glen Loch and Lake Wissota.
Until now about the only thing the Lake Association has been able to do is try to harvest the plant frequently enough to keep the water clear.
Using a $100,000 weed harvesting machine, the Lake Association harvests from May to September multiple time per week. Over the course of the season, from 200-300 tons of the plant are removed from the lake.
“If we didn’t harvest, it would be hard to motor through the lake,” Bakken said, explaining that the matted weed would bind up a boat’s propeller. Even if the boat did make it through, it would only make the problem worse. The weed reproduces through fragmentation: every piece the plant gets cut in will grow into a new weed.
Even harsh winters, like the current one, don’t seem to have much of an effect on the plant.
“In fact, it seems to grow throughout the winter under the ice,” Bakken said.
But the Lake Association is planning on using this grant to pay for a study to look into the best way of handling the weed.
“The study will provide good direction on how we can best deal with the invasive plant,” Wanserski said.
Some lakes have been drained in an attempt to get rid of the weed, while others have been treated with chemicals. Both are difficult and expensive options.
Continuing to harvest as the Association has been doing may be the best option, Bakken said, but “we’re concerned that this might not be the best management at this time.”
With an area of about 80 acres that is only about 11 feet deep, the man-made lake that was once a holding pond for a sawmill isn’t the biggest lake out there. But it has been a popular spot for fishing, especially for bluegill and bass.
“Historically, it’s been a great recreational lake,” Bakken said.
If the milfoil situation can be solved, the Association isn’t concerned about the further health of the lake.
“It’s a fertile lake,” Bakken said.