Aquatic Invasive Plant Identification Cards: Hydrilla vs. Common Waterweed
DOWNLOADSeptember 2, 2026 - Jo Latimore, Paige Filice, Erick Elgin, and Chelsea Cooper
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EmailWith its abundance of lakes, rivers, and wetlands, Michigan is vulnerable to the impacts of aquatic invasive plants. Invasive plants can negatively impact habitat, water quality, and biodiversity. Fortunately, new invasions can often be stopped if caught early. To help Michiganders identify invasive aquatic plants, Michigan State University Extension created a series of illustrated identification cards.
Learning to identify aquatic invasive plants is critical to slowing their spread in Michigan lakes, rivers, and wetlands. If your organization is interested in large quantities of any of these identification cards for distribution, they are currently available in packs of 100 of each design at no cost by filling out our request form at bit.ly/aiscards. You may also be interested in our more detailed 2025 publication, “Aquatic Invasive Plants: A Field Guide for Michigan Lakes, Streams, and Ponds.”
Hydrilla vs. Common Waterweed
Hydrilla is a very recent invader to Michigan waters; in fact, it is currently only known from one invasion of ponds in southwest Michigan. It has simple green, serrated leaves and a long flexible stem; spines are also sometimes found on the underside of the leaf along the midvein. These visible serrations set it part from Elodea (waterweed), a native beneficial plant. Hydrilla also differs in that it produces tubers in the sediment.
