Eurasian water milfoil is an exotic plant that arrived in the U.S. in the 1940's through the aquarium trade. Scientists say it's destroying native plants like a biological wildfire out of control. The weed is now found in Ohio and 47 other states. Biologists have several methods to control it, but they're still looking for an ideal solution. A small Stowe, Ohio company is revolutionizing the way communities get rid of the milfoil. 90.3's Janet Babin reports.
Janet Babin- The name Eurasian Water Milfoil might not have a familiar ring, but the weed is well known to many who've been out boating this summer, especially on lakes. Recreational lake users sometimes have to manually clear clumps of the long stringy stuff from boat propellers. It looks like a cross between seaweed and an evergreen bush. Earl Wonk has run into it during his travels with a boat he docks at the Wildwood Yacht Club on Lake Erie.
Earl Wonk- It was so bad that you had to throw the engine into reverse to knock off the plants cause they would run around your prop and get stuck in there and you're going forward and the boat's not moving.
JB- Milfoil roots in lake bottoms. It can be found in water as deep as 26 feet, growing as much as an inch a day at summer's peak. The weed often spreads by boats (and) fragments of milfoil not cleaned from motors easily detach and root in new lakes. Mark Coscarelli is with the Michigan Department of Environmental Quality. He says Eurasian water milfoil infests hundreds of Michigan lakes.
Mark Coscarelli- It grows in mats to the surface, it crowds out native vegetation, it can become unsightly, it can, if boats run through it, it gets cut up and washes up on beaches.
JB- While trying to figure out how to control the milfoil in Vermont, aquatic biologist Holly Crosson found a native bug that makes a steady diet of Eurasian Milfoil. Crosson, who works with the Vermont Natural Resources Agency, suspected the tiny beetle was the reason milfoil was not a problem in some lakes. Vermont was awarded a federal grant to investigate. The conclusion indicated that the beetles lay eggs on top of the plant, eat it, and can destroy it within about five years.
Now that research is licensed to Enviroscience, a Stowe, Ohio company with about two dozen biologists headed up by Marty Hilovsky. In his lab filled with fish tanks, he grows thousands of tiny black beetles, then sells them to lake managers around the country.
Marty Hilovsky- We're using a native beetle to combat an exotic species. We're using a species that's already here and all we're doing is increasing it in number giving it a jump-start out in the wild.
JB- Scientists often use bio-control to curb exotic weeds - traditionally that means using a foreign bug to eat the foreign plant. But sometimes the bug ends up overrunning indigenous plants that have no defenses against it. Hilovsky says using a native bug eliminates that potential problem. Two years ago, he heard a lecture about the beetles and decided to try selling them. Even though the company's strength, he says, is it's scientists, not it's salesforce, Hilovsky knew clients were looking for natural ways to kill the milfoil, without causing problems for local ecosystems - so he jumped on what some consider a risky proposition.
MH- We could make more money if we stayed with herbicides or mechanical harvesting or that - we really believe in this - we believe that bio control has a future in lake management.
JB- Biologist Chris Brant is Enviroscience's milfoil project manager. She's leading three part time staffers into Ohio's Lake Magador south of Cleveland, to collect the milfoil-eating beetles. Dressed in wet suits, with flippers and snorkels in tow, each assistant collects about one hundred bugs that are brought back to the Enviroscience lab to propagate. The company now boasts beetle clients in ten states, including Michigan. Mark Coscarelli says his department paid the company ten thousand dollars to stock several lakes with thousands of beetles. Two summers later, Coscarelli still calls the beetle method experimental:
MC- We have seen some success in Paradise Lake. We've seen reduced beds of Eurasian water milfoil - there's visible scars, remnants... in fact, the weevil is doing it's job in eating it's host. In other cases I've seen where following a year of introduction no weevils could be found.
JB- Others are skeptical of the beetle method - Holly Crosson, who first proposed the idea of using the beetles to control milfoil, thinks the process is still too experimental to sell. But Hilovsky says the company's already doubled the amount of beetle business for next spring and summer. He says if lake managers are looking for alternatives to milfoil management, to date his company is the only choice. In Cleveland, Janet Babin, 90.3 WCPN, 90.3 FM.