Aquatic Plant Management

Plant identification

Use this aquatic plant identification guide to identify the types of plants you see on Lake Johanna. 

The DNR limits the amount of the total lake surface that can be treated.

The DNR wishes to maintain fish habitat and native species, but still ensure that residents can control vegetation that affects their use of the lake (beaches, boat docks, boat lifts, swimming rafts, and access to the larger lake). Given the DNR limits, treatment will benefit our individual properties, but can not control or eliminate vegetation lake-wide, which would be both illegal and cost-prohibitive.

The chemicals used are contact herbicides. They knock down the growing parts of plants above the lake bed. They are not systemic herbicides that kill the entire plant. Completely removing vegetation, especially native species, opens up the lakebed to the further spread of invasive species.