Australian Water Clover

Marsilea mutica

Family: Marsileaceae

Other Common Names: water clover, four leaf clover
Weed class: monitor list
Year Listed: 2017
Native to: Australia and New Caledonia
Is this Weed Toxic?:

This plant may be toxic to cattle, horses, and sheep.

Legal listings:

This plant is on the quarantine list. It is prohibited to transport, buy, sell, offer for sale, or distribute plants or plant parts of quarantined species into or within the state of Washington or to sell, offer for sale, or distribute seed packets of seed, flower seed blends, or wildflower mixes of quarantined species into or within the state of Washington. Please see WAC 16-752 for more information on the quarantine list. For questions about the quarantine list, contact the Washington State Department of Agriculture's Plant Services Program at (360) 902-1874 or email PlantServices@agr.wa.gov.

Why Is It a Noxious Weed?

Australian water clover is on the monitor list - it is not a listed noxious weed in Washington. Please contact its sponsor Wesley Glisson at wgli461@ecy.wa.gov to report locations or for more information.

How would I identify it?

General Description

Australian water clover is a perennial aquatic fern that has leaves dived into four lobes, looking like a clover. Leaves are two tone in color and tend to float on the surface of water.

Flower Description

Plants do not flower, rather they have a small rounded structure called a sporocarp that is on a short stem, growing from the rhizome near the base of the petioles. Sporocarps contain many small spores.

Leaf description

Leaves are four-parted like a clover and are two toned, being green on the lower half and brown to purple on the top half. Leaves to around 2 inches wide.

Stem description

4 to 12 inch tall stems help attach the floating leaves to the aquatic substrate.

Where does it grow?

Plants grow in ponds, lakes and other aquatic environments.

How Does it Reproduce?

Plants spread by rhizomes and by spores.

How Do I Control It?

Herbicide Control

Because herbicide availability and regulation differ between states, we recommend the Washington Department of Ecology website for information on aquatic weed management and herbicides, or contact your county noxious weed coordinator