Join the search for hydrilla

Hydrilla Hunt! program solicits help of lake and river enthusiasts to discover invasive aquatic plant

GLENCOE, Ill. (June 12, 2013) – Boaters, anglers, swimmers, and others who enjoy Illinois’ lakes and rivers are keeping their eyes peeled this summer for an aquatic “superweed.” Through the Hydrilla Hunt! program, citizen volunteers are on the lookout for a highly invasive aquatic plant named Hydrilla verticillata, or simply “hydrilla.”

Recognized as one of the world’s worst weeds, hydrilla can grow an inch per day and form dense mats of vegetation at the water surface. Within the past few years, hydrilla has been discovered in Wisconsin and Indiana and it is expected to arrive in Illinois very soon. Our desirable native aquatic plants, sport fishing, native wildlife, waterfront property values, and recreational uses might all be seriously impacted.

“Early detection of hydrilla could save Illinois millions of dollars in control costs,” noted Cathy McGlynn, coordinator for the Northeast Illinois Invasive Plant Partnership (NIIPP). “Experience from other states shows that once a waterway becomes infested with hydrilla, it’s nearly impossible to control. Our hope in Illinois is to identify the plant at a very early stage when populations are still small enough to eradicate and manage,” added McGlynn.

The strain of hydrilla that has been found in the northern United States is believed to have originated in Korea. It grows on mucky as well as sandy bottoms of lakes and rivers, and from very shallow water to depths of 20 feet or more. It can be spotted snagged on fishing lines or on boat anchors, or by noting plants seen while boating or growing along the sides of a pier. Hydrilla spreads quickly, since just a small stem fragment of hydrilla can sprout roots and grow into a whole new plant.


Anyone can participate in the Hydrilla Hunt! program. Volunteers are encouraged to take a more detailed look at aquatic plants they encounter while out and about on Illinois’ waterways. A Hydrilla Identification Sheet (available for download at the program’s website, see below) can be used to differentiate hydrilla from look-alike plants such as Brazilian elodea and American elodea. Volunteers who suspect they may have found hydrilla are asked to take several digital photographs and email them to the Hydrilla Hunt! program for verification.

For more information, including how to become a Hydrilla Hunt! volunteer, a Hydrilla Identification Sheet, fact sheets, and other resources, visit www.niipp.net/hydrilla. The Hydrilla Hunt! program is coordinated by the Northeast Illinois Invasive Plant Partnership, the Chicago Botanic Garden, and the Lake County Health Department-Lakes Management Unit. Funding support has been provided by the Illinois Department of Natural Resources through the Illinois-Indiana Sea Grant.