It's what you might not see in Lake Delton that's fueling a fight. The village plans to fight a variety of invasive plants that could threaten the beauty of the popular spot -- if left unchecked. The problem is these plants grow fast, with little regard for native species. They pose no health risk but create an ugly lake, which is a risk for local business.

"It's a major draw for the area," Village Trustee Les Bremer says of Lake Delton.
Scenic Lake Delton. Resorts rest on its shores. Performers play on its water. But it's also home to ducks and a few non-native, invasive plant species.

"I would say the Eurasian watermilfoil would be of most concern," Donna Sefton with the DNR says.

A private expert hired by the Village of Lake Delton says the stubborn plant has spread from a couple of acres to five acres within the last few years. It's one of three invasive plants being monitored at Lake Delton.

"You can get a little fragment of that and it can grow into a whole new plant," Sefton says.

And that plant can grow as much as two inches a day, reaching 20 feet long or form a canopy.

"If the plants are chopped up by boats or other activity, they can grow into new plants in different parts of the lake," Sefton says.

But the more it spreads, the more difficult to boat or to swim. That's why this plant with fine leaves could become a thick problem for an area, heavily dependent on having fun.
"You have thousands using the lake every year," Bremer says.

Hotel owner and Village Trustee Les Bremer says the village is taking action to monitor and treat the lake before the problem gets too deep.

But also of concern are the E. coli readings from streams that feed into Lake Delton.

"It's something to be kept a close eye on and controlled," Bremer says.

Experts blame runoff from nearby farms and horse stables as well as the local duck population, but say they do not expect any postings or beach closings.

Meantime, Sefton says anyone can help protect the lake by cleaning boats of vegetation to prevent the spread of aggressive weeds. She says a healthy lake -- full of native plant life -- is a clean lake.

The firm monitoring Lake Delton says it plans to use an herbicide to tackle isolated patches of milfoil. And, it will monitor E. coli levels and educate landowners on creating buffer zones to reduce runoff better.