SPRINGFIELD – Hydrilla, a highly invasive aquatic plant, has been discovered in DuPage County, marking the first known occurrence in that county and only the second known report in Illinois.
Hydrilla is considered one of the world’s worst aquatic weeds. It can grow up to an inch per day and form dense mats of vegetation with negative impacts on boating, fishing, swimming, native aquatic wildlife, and property values. Control and eradication efforts can cost millions of dollars over many years.
The Illinois Department of Natural Resources (IDNR), along with other state and local agencies, are working to track the spread of this aggressive invasive plant in waterways and determine the most appropriate containment and eradication strategies.
The public should be aware that this plant looks very similar to the native Elodea species, but there are a few key features that can be used to differentiate them. Hydrilla has whorls around the stem of more than three leaves with often visibly toothed edges.
The hydrilla found in DuPage County may have been unintentionally released from a homeowner’s aquarium or a water garden. Although hydrilla is a federal noxious weed that is illegal to buy, sell, or transport and is banned in Illinois, it is often found in the aquarium and water garden trade.
People can do their part to limit the spread of this invasive plant and other aquatic invasive species by taking these actions:
- Remove all plants, animals and mud from any equipment that is used in waterbodies.
- Drain all water from boats and gear.
- Dry everything thoroughly with a towel or heat.
- Do not dispose of plants or animals from aquariums or water gardens in local waterbodies.
Anyone who suspects they have identified hydrilla in a waterbody should notify the IDNR Aquatic Nuisance Species Program at dnr.ans@illinois.gov. For additional information on hydrilla, please refer to the Great Lakes Hydrilla Collaborative.