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Hydrocharis morsus-ranae


European frog-bit in-situ
European frog-bit in-situ

Habitat: European frog-bit (or frogs bit) is found in the floating-leaved plant community. It is a free-floating plant that thrives in open marsh habitat and quiet backwaters, forming dense floating colonies.

Description: European frog-bit is a small free-floating aquatic plant. Its small kidney or heart shaped leaves (1.5 to 6.5 cm long) are not anchored to the bottom sediments. The leaves have elongated stalks (4-6 cm long) and occur in clumps, forming a bouquet-like rosette. Unbranched root-like tendrils (resembling slender bottle brushes) dangle below. The flowers of European frog-bit have three white petals with a yellow center.

European frog-bit Range Map
U.S. range map of European frog-bit

Origin and U.S. Range: European frog-bit is native to Europe. It is not native to New England and is considered invasive to this area. Nearby populations occur in Vermont and New York.

European frog-bit flower
European frog-bit flowers have three
white petals and a yellow center

Annual Cycle: European frog-bit is an aquatic perennial that propagates primarily by vegetative means. Mature plants send out multiple offspring on trailing runners (stolons). Winter buds (turions) form during the summer, and fall to the bottom as plants begin to decay at the end of the growing season. In the spring the turions break dormancy, bob to the water surface, and sprout new growth. Flowers, followed by fruits, occur during the summer.

Look Alikes: May be confused with fragrant water-lily, little floating heart, spatterdock, and water shield.

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European frog-bit flower European frog-bit in hand European frog-bit Colony European frog-bit reproductive structuresEuropean frog-bit range map European frog-bit Illustration

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