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Eurasian water milfoil (Myriophyllum spicatum L.) is an invasive aquatic plant native to Europe, Asia and northern Africa. First found in a Washington D.C. pond in 1942, the milfoil took only eight years to spread throughout the Midwest and several Western states. Today, it has spread across the country invading lakes, reservoirs and other areas where standing or slow moving water is found  - including 126,000 acres in Indiana.

Eurasian water milfoil is a submersed perennial plant with a very long underwater stem. As the plant reaches the water's surface, it branches out vastly. Its leaves are whorled with four feathery leaves per whorl. In the late summer, small reddish flowers emerge above the water on a spike grown from the tip of the stem.

According to the United States Geological Survey, the aquatic invasive was "probably intentionally introduced" to our waters. Invasions could have started by people dumping aquariums in public waters, landowners planting it intentionally for fish habitat or recreationists unknowingly transport fragments from one body of water to another. Unfortunately for us, Eurasian water milfoil is capable of reproducing quickly by broken fragments that can easily set root and grow into a new plant. 

Eurasian water milfoil is a concern because it can completely destroy stands of native vegetation that our aquatic species need for food and shelter. It also has adverse effects on recreational activities such as boating and fishing. Unfortunately these same activities are also responsible for the spreading of this very adaptable invasive plant.

Managing Eurasian WaterMilfoil

Prevention is the best management as it is the easiest and cheapest way to control Eurasion water milfoil. Like other aquatic invasive species, this water milfoil likes to "hitchhike" from one body of water to another. To help stop the spread of this invasive plant, make sure to rinse off any mud and plant material from equipment such as boots, wading gear and your boat before leaving the access area. Also, do not dump aquariums or water garden plants into wild bodies of water. Instead, seal them in a plastic bag and throw in the trash.

For more information on how to control Eurasian water milfoil through, check out Purdue University's Identifying and Managing Aquatic Vegetation guide by botany professor, Carole A. Lembi.