One down, one to go.

The first of two contractors hired by the Glen Lake Association to look for Eurasian watermilfoil (EWM) in the lake did not turn up any evidence of the nasty invasive plant after searching this week, association scientist Rob Karner tells The Ticker.

This contractor used a method in which a rake is dragged across the bottom at random intervals along a grid pattern, Karner says. While he’s “cautiously optimistic” after getting the all clear from the first contractor, it’s too soon to say the plant doesn’t have a foothold in the lake.

“I don’t want to diminish or shortchange the first contractor’s work, because they have a proven method, they have experience, and they see EWM all the time,” he says. “But we’re in the middle of a process of using two different contractors with different methodologies.”

The second contractor, scheduled to search later this month, will use an underwater remote operated vehicle (ROV) to search for the invasive plant. They’ll also be looking specifically at a series of nearly 40 potential “hot spots” that were identified in an aerial drone survey last year.

And even if the best-case scenario occurs (the second contractor also comes up empty handed), the association intends to pour a ton of renewed energy into its prevention efforts, the largest of which is a staffed boat wash at the lake’s only public boat launch.

“We’re not going to rest easy even if the second contractor says they didn’t find it,” Karner says. “We’re never really in the clear. Any time a boat comes in from another lake, it might have (EWM) on it.”

The search was triggered last year after detached pieces of EWM were found floating in the water near the launch. It’s not clear if the pieces came from another lake via an unwashed boat or if they were from a plant growing in the lake, but they were enough to sound the alarm bells.

While it was too late in the season to mobilize a large-scale search, aerial surveying was completed to support the searches now underway.

Neighboring Lake Leelanau is several years deep in own battle with EWM. Lake Leelanau Lake Association is leading the charge, with support from the Grand Traverse Band of Ottawa & Chippewa Indians and others. Significant progress has been made, but the war is far from over.

Introduced to North America more than 100 years ago, EWM is now one of the most widely distributed invasive aquatic plants on the continent. Like many invasive species, the plant is a problem because of its ability to rapidly spread and choke out native species, creating large, dense swaths that can completely change the character and ecology of a lake.

It is present to some degree in several northern Michigan lakes, but tends to present a more significant problem in shallower, warmer lakes or similar areas of larger lakes. Litle Glen Lake, for instance, is at a much higher risk for substantial infestation than the colder, deeper Big Glen Lake.

Recent weather trends of milder winters and earlier springs have helped the plant substantially by extending the growing season.

Boat washes are among the best lines of defense against the spread of EWM and aquatic invasive species, which often spread from lake to lake as they hitch rides on or in boats. GLA has operated a full-service boat wash at the boat launch for many years, something that’s quite rare across the state.