European Frog-bit

Photo by Meghan Johnstone, APIPP

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Common Name: European frog-bit
Scientific Name: Hydrocharis morsus-ranae
Origin: Europe


European frog-bit is a free-floating annual. The leaves are leathery and round with undersides that may be dark purple. White flowers with yellow centers bloom in the summer. The leaf stem of European frog-bit lacks a midline groove which distinguishes it from its native look-alike American frog-bit, Limnobium spongia.


This plant grows well in quiet, open water including marshes, ditches, swamps, and sheltered coves.


European frog-bit has rapid vegetative spread and forms dense mats, which can limit light penetration and inhibit recreational use.

NYS Threat Ranking Assessment Score = Very High, 85.57


Limited information exists about control techniques for this species. Hand pulling may be suitable to control individual plants or small infestations.

Distribution: View Map