Taking know how from the farm to control Eurasian watermilfoil in the waters of Green Lake

Bob Schemel lifts his hands to show that the pontoon boat is being guided entirely by the John Deere system that otherwise can steer his tractor or combine. Brian Stenquist and Ann Pierce, both with the Minnesota Department of Natural Resources, are watching.

SPICER — There are a lot of thoughts that go through a farmer’s mind in the cab of the tractor or combine, but there’s one that Bob Schemel mulled over long and hard.
For a few years, he and Roger Sowder have volunteered their time as part of the Green Lake Property Owners Association to apply herbicide on the patches of Eurasian watermilfoil located about the lake.
The invasive aquatic plant was first discovered in the lake in 2000, and the GLPOA has invested roughly $100,000 to date to control it. At the start, volunteers hung over the sides of boats and cranked away at hand-held spreaders like you use on your lawn to disperse the herbicide.

Bob Schemel

Schemel and Sowder have elevated the art to science ever since Schemel had a Eurkea moment in the cab.
He asked himself: Why not use the technology of precision farming to control Eurasian milfoil in Green Lake? One of his first steps was to enlist the help of Kyle Sietsema at Haug Implement in Willmar.
Today, a green and yellow, John Deere globe normally found atop combines is a fixture on Schemel’s pontoon. Just as is the case when he is in the field, the system uses signals from satellites and a fixed tower to precisely fix the pontoon boat’s location on the lake. The system can actually steer the pontoon boat to the patches of Eurasian milfoil scattered all over the nearly 6,000 acre body of water. The coordinates for each patch are recorded in the system’s computer.

Roger Sowder watches as the herbicide is dispersed directly over a patch of Eurasian watermilfoil in Green Lake.

The system assures that herbicide is applied precisely where it is needed, and no more. It’s all about good stewardship, according to Schemel. There is less collateral damage from herbicide that might otherwise miss the intended target.
The hope is that the science behind precision farming will make the control efforts more effective.
It is not possible to eradicate the invasive plant at this point, but the benefits of control are real. The total acreage of Eurasian watermilfoil had grown to 15 acres after its initial discovery, but now has been knocked down to six or seven acres.
Protecting water quality in Green Lake is a multi-faceted matter. It requires responsibility on everyone’s part to prevent the spread of invasive species to the waters. It also takes on-going work to keep excess nutrients and sediment from the water.
All of the above are being done on Green Lake, and no doubt much of the credit belongs to the GLPOA. There are few lakes in the state that can match the commitment shown here, or the ingenuity.

— Tom Cherveny