European Frog-Bit Invasive

Please see the below message regarding frog-bit,  a non-native water lily look-a-like, spreading through parts of Michigan.   Unlike invasive weeds such as Eurasian watermilfoil already established in Wisconsin, this one falls into the “prohibited” category of the invasive species law because of its non-existence (or near non-existence) in the state.   Please report any suspicious sightings.

Welcome back summer!!!!

Ted Ritter

Vilas County Invasive Species Coordinator

http://www.vilasconservation.org

Exotic Aquatic European frog-bit Spreading Throughout Michigan

Invasive Free Floating Flowering Plant Forms Dense Monotypic Meadows

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 in 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 may force out other beneficial native floating plants (like water lilies) and effectively prevent 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.