Fanwort is a submersed, floating plant with short rhizomes (underwater stems). The shoots are green and sometimes reddish-brown. The leaves are either submersed or floating; submersed leaves are finely divided and arranged in opposite pairs on the stem. Floating leaves are small and inconspicuous and are less than 1/2 inch long and 1/3 inch wide. The leaf blade attaches to the center, and its flowers are white and small and float on the water surface.


  • 1

    Recreational activities such as swimming, fishing, and boating can be impaired and even prevented.

  • 2

    Dense mats of Aquatic weeds can block sunlight from native submerged plants.

  • 3

    Aquatic weeds greatly detract from the aesthetic appeal of a body of water.

  • 4

    Excessive growth can lead to fish stunting and overpopulation. This occurs because the production of too much habitat prevents effective feeding of small fish by larger fish.

  • 5

    Aquatic weeds can cause fish kills.

  • 6

    Aquatic weed growth provides quiet water areas ideal for mosquito breeding.

  • 7

    Weeds impede water flow in drainage ditches, irrigation canals, and culverts and cause water to back up.


Fanwort can be found in most of the contiguous states.