Existing Invasives

These invasive species are existing threats to our Big Whitefish Lake waters and the surrounding lake basin. Click on each name to see photos of the species.

Curly Leaf Pondweed: (Listed as a restricted noxious weed by the MI Department of Agriculture.) It grows in early spring inhibiting growth of native plants. Midsummer die-back results in masses of dead vegetation, increase in phosphorus levels and potential algae blooms. Herbicide applications* at low rates in early spring provide effective control while later applications are ineffective.

Eurasian Milfoil: (Listed as a restricted noxious weed by the MI Department of Agriculture.) Milfoil easily transfers on boats that go in and out of different lakes. It begins to photosynthesize and grow prolifically in early spring, dominating an area and limiting light available to other aquatic life. Dense colonies of plants clog boat motors impacting recreational use. Efforts to control milfoil growth include reducing nutrient enrichment (like shoreline fertilizer) and hand pulling out colonies. Biological control with native herbivorous weevil shows promise. Herbicide treatments* provide short-term control (up to 3-4 years).

Japanese Knotweed: This species is prohibited under Michigan law; forms dense thickets that shade out natives; rhizomes can damage pavement; extremely difficult to eradicate; spread by flood waters.

Purple Loosestrife: This species is restricted under Michigan law; attractive but persistent weed; spreads vigorously in moist soil conditions; crowds out native wetland plant species.

Quagga Mussels: Quagga mussels filter phytoplankton from water, decreasing the food source that zooplankton rely on and altering the food web. Filtering the water also increases the transparency, which can lead to increased light penetration that can change species dominance of aquatic plants. The water filtration by the quagga mussel also creates waste, which creates a foul environment and can contain toxic pollutants that can be passed up the food chain. The rapid colonization of these mussels on hard surfaces can clog water intake structures and they are costly to remove and control.

Zebra Mussels: Zebra mussels create protein strands that can attach to any surface, causing major damage as colonies can block pipes, affecting power plants and water-treatment facilities. Additionally, zebra mussels impact water quality by their decomposing bodies, waste and filter-feeding ability. These traits disrupt fish-spawning habitats and can cause water to have a four odor or taste. Zebra mussels are a very tolerant and prolific species, making it very easy for them to quickly spread to new environments and making it difficult to control.

* Permits are required for herbicide use in water bodies and wetlands.