Aquatic Invasive Species

Monitoring for aquatic invasive plant species allows you to act as a first line of defense

The information that you gather on your lake will help maintain a record of aquatic vegetation as well as provide an early warning for new nuisance plants. Your efforts will ensure that new invasive plants be controlled early on.

By early identification of new invasive plants, such as Brazilian elodea and Hydrilla, Indiana has been able to keep these invasive plants from spreading. You can also prevent an invasive plant such as these from becoming a problem on your lake through early detection.

We currently have a recommended strategy for how you conduct your vegetation survey. Over time you will discover what method works best for your group and your lake.

Currently, we ask that you report your information through EDDMaps—Early Detection and Distribution Mapping System, or the Great Lakes Early Detection Network as part of EDDMaps.

Report your information through EDDMaps

How to monitor for invasive plant species

  1. Based on the lake size and the number of volunteers, it will be beneficial to have a group of monitors. You will want to break up the shoreline into sections and assign segments to different volunteers. It is usually helpful to assign segments where the volunteers live along the shoreline. This ensures more monitoring and familiarity with the shoreline. This will allow everyone to break up the work. One person will be the Captain of the group and everyone will report suspicious finding to one person who will be our contact. The Captain will be in charge of setting up a schedule for monitoring and ensuring that everyone does the monitoring.
  2. Once you have the sections set up, begin monitoring by moving slowly around the perimeter of the lake, as close to shore as possible. A weaving or zigzag pattern away from the shoreline to cover all the area where the light penetrates to the bottom of the lake. This will be further out in some lakes depending on the gradient of the lake bottom.
  3. Plan to monitor on days when the lake is calm. Wind and large ripples will make it more difficult to survey plants.
  4. Scan the vegetation as you travel along the shore. Attempt to identify both the surface and submersed vegetation. It is important to also scan the shoreline, as fragmented vegetation will wash up on shore, especially after storm events. Pull submersed plants with the rake if necessary for easier identification. Be careful not to disturb the bottom of the lake.
  5. Using a map of your lake make note of plant species and abundance using a system of letters or numbers. Make marks closer together to display denser beds of plants. It is not necessary to make note of all the vegetation in the lake, only invasive plants or anything unusual. This map will be an excellent way to document current invasive plants and will be a great reference for future use.
  6. Take extra time to thoroughly evaluate areas around any boat launch or protected coves. Boat launches are areas of high use and a source of plant introductions making them ideal areas of invasion. Coves are another area likely to have invasive plants. Wind blows plant fragments into coves where they are protected and can easily take root.
  7. Conduct a plant survey at least 2-3 times during the summer growing season. This will allow you to map your lake and document changes during the growing season. The best time to do the vegetation surveys is from May-September. Once a month is ideal, but not necessary to participate.
  8. Watch out for look-alike plants. They resemble exotic plants but are not invasive. Look-alike plants have some distinct characteristics that distinguish them from the invasive plants. Be sure to use the identification materials to distinguish if you have an invasive plant.

Aquatic plants are an ecologically important part of the lake ecosystem. We are not looking to remove vegetation from the lake only to control invasive plants and prevent them from becoming a nuisance.  The Invasive Species program is a method of documenting vegetation and helping us become better stewards of our lakes. 

What should you do if you think you have spotted an invasive plant but cannot be positive?

  1. Note the location of the plant by making notes on reference points to something on land. Place the marker buoy close the plant in question. If possible collect GPS coordinates of the plants location.
  2. Collect the plant using the rake if necessary. Make sure it includes the stem and leaves and flower and fruit if present.
  3. Wrap the specimen in moist paper towel and put in zip lock bag and mail to:

Indiana Clean Lakes Program
1315 East 10th Street, Rm 371
Bloomington, IN 47405

Be sure to include your contact information with the plant and the lake location where it was found. Only mail samples Monday-Wednesday to ensure that they make it to us when they are still in good condition. If you have any doubt about sample shipping feel free to contact us. If it is over the weekend or at a time you cannot mail the sample place it in the refrigerator and wait to mail.

  1. We will notify you once we have a proper identification.

Sample specimen bags are available upon request!


  1. Take a digital image of the plant placing a representative object next to the plant for size and email it to inclp@indiana.eduBe sure to save the representative sample in case we would still need it to mailed to us.