Herbicide Costs vs. Mechanical Management on Northern Wisconsin Lakes

Thu, 18 Dec 2025 17:43:03 +0000

For over a decade, lakes across Northern Wisconsin have spent staggering sums of money attempting to control Eurasian water milfoil with herbicides. The Lower Eagle River Chain of Lakes Commission, formed in 2007 specifically to tackle this invasive species, is a case in point.

Eurasian water milfoil grows aggressively, uprooting native vegetation, disrupting aquatic habitats, and interfering with recreation. By 2013, the Commission was spending up to $250,000 per year on herbicide treatments to control approximately 300 acres of milfoil. Grants helped fund these efforts, but by the mid-2010s, funding had dwindled to around $50,000 annually.

After a decade of chemical treatment, the Commission made a bold decision to stop using herbicides altogether. The results? Within a few years, the milfoil population began rebounding. According to the aquatic ecologist who has monitored these lakes for 18 years, the plant is “too big, it’s too much” for manual removal alone, which costs roughly $2,500 per day.

The lesson is clear: eradication with herbicides is expensive, temporary, and environmentally damaging. Even if chemicals were used without regard for ecological impacts, controlling the entire population long-term is not practical.

Instead, a management-focused approach should to taken to target plants that interfere with navigation and recreation rather than attempting total eradication. Mechanical harvesting offers a solution; it doesn’t attempt to eliminate every plant but efficiently manages growth, maintains recreational access, and avoids repeated herbicide costs.

After more than a decade of observation, the evidence is in: spending hundreds of thousands of dollars chasing eradication with chemicals is far less effective than strategic, mechanical management. It’s time for a shift in mindset: toleration and control, rather than endless eradication efforts, may be the only sustainable way forward for our lakes.

Black Lake Weed Harvester Removes 6,000 Pounds of Invasive Milfoil to Improve Boating Access

Tue, 19 Oct 2021 21:14:47 +0000

In the last few decades, the lake’s weedy, northern-most portion has clogged hulls and deterred boaters from entering the lake from the Oswegatchie River. Patches of weeds greet the water’s surface near every dock, and nearly invisible from a distance on a windy day, matted greenery creates a basin of weeds seven-feet-deep in some spots.

As part of a summer-long effort to cut a channel in Black Lake (New York), the Black Lake Association used an aquatic weed harvester to cut and remove invasive Eurasian watermilfoil. On one September afternoon, the Black Lake Association harvested roughly 6,000 pounds of invasive wet weeds in less than two hours.

The harvested vegetation was taken to a local dairy farm to be used as fertilizer.

navigation channels – Aquarius-Systems

Herbicide Costs vs. Mechanical Management on Northern Wisconsin Lakes

Black Lake Weed Harvester Removes 6,000 Pounds of Invasive Milfoil to Improve Boating Access