Invasive Species (Aquatic) -


(Cabomba caroliniana Gray )

Photos & Description courtesy of IPANE

What Fanwort does to the habitat

Fanwort grows in extremely dense colonies and is known to clog drainage canals and freshwater streams. It crowds out established native species and restricts recreational activities like swimming and boating. Shoots have been seen under the ice in winter, so it gets a very early start.


Still sold in aquarium stores, the plant is often flushed into the local water system. Since it can root from vegetative parts, it is easily spread.



Drawing water off the pond to dry out the fanwort has been shown to work. But the plant needs to be well dried out not to reproduce from seed.


Endothall and flurodine herbicides are also known to work for control.


Common Name

Full Scientific Name

Carolina fanwort

Cabomba caroliniana Gray

Family Name Common

Family Scientific Name

Water-shield family Cabomba caroliniana


Botanical Glossary

Cabomba caroliniana is a submersed, rhizomatous, aquatic perennial that can have stems up to 2 m (6.5 ft.) long. It has two types of leaves. The petioled, submersed leaves are opposite, and sometimes whorled, peltate in form, and are 2-5 cm (0.75-2 in.) in width. These leaves are repeatedly divided into filiform segments. The small floating leaves are few and linear-elliptic in shape, have entire margins and often have a basal notch. These leaves are 6-20 mm (0.25-0.75 in.) long. The long-peduncled (3-10 cm (1.2-4 in.)) flowers are most often white with yellow at the center, but are rarely pink or purplish. The sepals and petals are about 1.25 cm (0.5 in.) across. The petals are auriculate at the their bases, and obovate in shape. The 3 ripened carpels are flask shaped. Page References Bailey 385, Crow & Hellquist 38, Fernald 642, Flora of North America 79, Gleason & Cronquist 46, Holmgren 44, Magee & Ahles 494.

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