Mosquito Fern

Other Common Names: duckweed fern, fairy moss, water fern, azolla

(Azolla caroliniana)


Mosquito fern floats on the surface, forming large colonies, and can be green or red to brown.


Mosquito fern is a free floating plant that has two lobes: one floating and one below the water’s surface. The leaves are oppositely arranged around the stem. Leaves are green when actively growing and red to brown when stressed.


Mosquito fern grows in quiet ponds, lakes, swamps, and in slow moving water or resting on mud. It is often found mixed with duckweed and/or watermeal. It can cover the whole pond quickly, blocking out sunlight and oxygen, leading to fish kills.


Mosquito fern can be found in the northeast, southeast, south, and midwest.