Michigan lakefront property owners would be well advised to keep a watchful eye out this spring and summer for yet another potentially harmful exotic aquatic invasive plant – European frog-bit (scientific name: Hydrocharis morsus-ranae).
Detected last summer near the Detroit River as well as within Saginaw Bay, Alpena and Munuscong Bay in Chippewa County, the highly invasive free floating plant is native to Europe, Asia and Africa, and was intentionally imported to Canada from Europe in 1932 for commercial use as an ornamental plant. European frog-bit has since spread to several rivers, Lake Ontario, Lake Erie and many other inland waters within the Great Lakes region.
Capable of rapid growth rates, European frog-bit often forms dense floating mats that force out other beneficial native floating plants (like water lilies) and effectively prevents sunlight from reaching native submerged aquatic plants. Dense monotypic mats of European frog-bit may also impede navigation and interfere with recreational uses such fishing and swimming.
The invasive free floating plant may be easily identified by the presence of a single white flower of up to three quarters of an inch in width with three rounded petals and a yellow center. The leaves of European frog-bit are one to two inches wide and are round to heart-shaped. The leaf bottom is purple-red with a spongy coating along the middle vein of the leaf that allows it to float on the water.
If you should see this rapidly spreading invasive plant, note their location and the extent of the infestation, and then call the Michigan Department of Natural Resources Early Detection and Rapid Response coordinator at 517-641-4903 – ext. 260.