Local officials battling milfoil – the water weed
By SARAH SUTSCHEK - ssutschek@nwherald.com
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| Water quality specialist Kathleen Paap tests water for E. coli amid Eurasian watermilfoil, an invasive plant species to the Chain O' Lakes area. (Nick Dentamaro – ndentamaro@nwherald.com) |
It might appear harmless with its featherlike appearance floating in the water, but this plant can impair boating and fishing on the Chain O’ Lakes.
Eurasian water milfoil is native to Europe, Asia and North Africa and might have been introduced to North America as early as the 1800s.
It first was documented in 1942. It spread quickly and reached the Midwest between the 1950s and 1980s.
It’s the invasive plant that local officials are battling on area lakes, although curly-leaf pondweed can be problematic, too, by forming dense mats that interfere with recreational activities. Both species can crowd out native water plants.
“In the Chain, there is definitely milfoil out there and some curly-leaf, too,” said Mike Adam, senior biologist for the Lake County Health Department. “Lake Catherine and Channel Lake have more of it up there.”
But the Fox Waterway Agency does not have an aquatic herbicide program to help eradicate the plants, Executive Director Ingrid Danler said.
“It’s a very expensive program to run, and right now our efforts are focused on dredging, public safety programs, and capital projects,” she said. “We know there’s a need for it, especially in some of our northern lakes and some of the lakes to the south, the smaller ones.”
Instead, one of the main efforts to help stop the spread is education.
“[Milfoil] seems to be the worst culprit,” Danler said. “The problem with that guy is you can transport him pretty easily on your prop and any bucket.”
The plant doesn’t necessarily need to be rooted to survive, she said.
Every couple of years, there seems to be a problem with people tossing plants into the water after they overgrow aquariums or water gardens, Adam said. Almost every year, water hyacinth pops up, another non-native, invasive plant that has been called the world’s worst aquatic weed.
“In the case of water hyacinth, the state of Florida spends millions of dollars every year combating it,” Adam said. “It probably wouldn’t get very well established here because of the winters, but plants are starting to develop a cold tolerance.”
Prevention boils down to education, Adam said.
“People think they’re doing the right thing by putting plants in the Chain, but it’s not a good idea,” he said.
In contrast, the city of McHenry seems to have successfully stayed milfoil in McCullom Lake – for now, anyway.
In spring 2004, the city spent more than $15,000 on an aquatic herbicide treatment for the 240-acre lake, Parks and Recreation Director Pete Merkel said.
“That kind of treatment does not completely eradicate it; it’s more of a control method,” he said.
Because the lake is shallow, with an average depth between 4 and 4˝ feet and 9 feet at its deepest, it’s not hard for milfoil to quickly gain ground, Merkel said.
“It has the potential to spread and cover 80 percent of the lake if we let it get out of hand,” Merkel said. “We have noticed it starting to come back, but it’s not as strong as in 2004, when we had a large portion of the lake inundated.”
In the mid-1990s, McHenry relied on a bug found naturally in McCullom Lake to help keep it milfoil-free. But the weevil just wasn’t able to keep up, Merkel said.
“They did a great job for us for a couple of years, but it got to be more than they could handle,” he said.
Crystal Lake is fighting off milfoil through herbicide treatments, including one applied last month to about 20 acres in the West Bay and Main Beach areas.
On the Chain, in order to apply an aquatic herbicide or nonchemical treatment, such as plant screens and sediment covers, residents must obtain a letter of permission from the Illinois Department of Natural Resources.
Any chemical application must be done by a certified professional.
“Private lake owners would also have a licensed applicator do the treatment, although they don’t need a permit,” Adam said.
However, individual property owners within 20 miles upstream of any potable water supply or food processing water supply might need a permit from the Illinois Environmental Protection Agency.
When applying treatments, the directions on the label should be strictly adhered to, Adam said.
“If they’re following the label, there are minimal effects,” he said. “The concern is oxygen levels in the water. If it gets too low, it can kill fish or the pH could get altered.”
Lakewood, for example, recently had this problem after a treatment for surface algae June 12 in the Turnberry subdivision. Strong storms caused the algae to die off too quickly and, combined with ample runoff, caused an oxygen depletion for fish, killing thousands of them.
