Tri-Lakes Aquatic Plant Control Program
The primary objective of the Tri-Lakes improvement program is to control the spread of invasive, exotic plants. In managing aquatic plants, it is important to recognize that aquatic plants provide several valuable ecological functions. Maintaining a diversity of native plants is as important as controlling nuisance and exotic species. The Midwest Aquatic Plant Management Society's plant reference chart is a great resource for identifying common native and invasive plant species.
Herbicide Treatments
Pending 2026 plant surveys.
Past Herbicide Treatments
Purple Loosestrife Biocontrol
The Tri-Lakes Improvement Board has initiated the stocking of Galerucella purple loosestrife beetles along Gilbert Creek, the tributary that flows into the channel between Blue Lake and Lake Mecosta. This area was selected due to the high density of purple loosestrife. Galerucella beetles selectively eat purple-loosestrife, making this biocontrol option viable as it will leave the native wetland plant species largely unimpacted. Kieser & Associates, located in Kalamazoo, Michigan, rears the beetles and will be placing eight stocked pots in the areas shown on the map and image below during the summer of 2026. Stocking will likely occur over multiple years to establish a reproducing population, providing long-term control. Stocking efforts will be documented via annual drone surveys.
Exotic plant species that are potentially a threat to the Tri-Lakes include Eurasian milfoil, starry stonewort, and curly-leaf pondweed. Early detection and rapid response are key to effective control of invasive aquatic plant species. Each year, biologists from Progressive Companies conduct multiple surveys of the lakes to identify exotic plant locations and targeted herbicide treatments are carried out to control nuisance plant growth. The herbicide treatments require a permit from the Michigan Department of Environment, Great Lakes, and Energy.
Eurasian milfoil
Starry stonewort
