Has your pond become tangled with overgrown weeds and algae? To regain control of your waterfront, you must know what you're dealing with and how to treat it. Learn how to identify emergent, floating, and submerged weeds and which herbicides best treat these common pond weeds below.
Emergent Pond Weeds
Often known as shoreline weeds, emergent pond weeds feature stiff stalks rooted in the shallow edges of your pond, with most of the plant emerging out of the water. Common emergent weeds include cattails, bulrush, Phragmites, and shoreline grasses.
Treatment Recommendations
Airmax Shoreline Defense emergent weed control is the ultimate chemical solution for controlling cattails and other shoreline weeds. The aquatic-safe glyphosate herbicide starts working on contact to provide long-lasting photosynthesis inhibition, and the systemic formula kills weeds all the way to the root.
An alternative, natural emergent weed removal option includes using an aquatic weed cutter like the Jenlis Weed Razer Pro to shear the stalks right at the roots. Ensure you thoroughly remove all cut vegetation with a rake and skimmer to prevent reproduction through fragmentation.
Pictures of Common Emergent Weeds
Floating Pond Weeds
When foliage crests the surface of your pond over deeper water, you are likely dealing with floating pond weeds. These tenacious plants may be rooted in the pond’s bottom or feature free-floating roots dangling in the water. Common floating weeds you may spot are duckweed, watermeal, water lily, water lettuce, and spatterdock.
Treatment Recommendations
Airmax WipeOut Pondweed Defense eliminates and controls both floating and submerged weeds throughout the entire growing season. This systemic fluridone herbicide is easy to apply and treats waterbodies with no outflow as a whole.
If you want to avoid chemicals, you must manually remove floating weeds with pond tools. The Pond Guy PondSkim quickly scoops up three square feet of stubborn duckweed and other nuisance floating plants with each pass.
Pictures of Common Floating Weeds
Submerged Pond Weeds
The bane of fishing ponds, submerged weeds grow in the muck and sediment along the bottom of your pond, hidden from sight. A characteristic that sets them apart from other weeds is that submerged plants have soft stems that cannot support emergent growth, so you will not see them rise above the water’s surface. Common submerged weeds your line might get snagged on are coontail, watermilfoil, Hydrilla, and many types of pondweed.
Treatment Recommendations
Airmax Ultra PondWeed Defense is ideal for directly targeting submerged weeds, and the broad-spectrum application of the active ingredient diquat makes it suitable for most other common water weed types as well.
Airmax Pond Dye Plus provides a more natural way to inhibit submerged weed growth by blocking portions of the UV spectrum from reaching the pond’s bottom. The added PondClear beneficial bacteria consume nutrients that fuel weed growth, providing a one-two punch without harsh chemicals.
Pictures of Common Submerged Weeds
Pond Weeds vs. Algae & Chara
Some pond weeds are commonly confused with algae. Duckweed and watermeal may be mistaken for string algae mats, while Chara resembles a few different submerged weeds. You’ll need to use your senses to distinguish which vegetation is invading your pond.
Chara is grainy and produces a musky odor when crushed, which true submerged weeds lack. Duckweed and watermeal both float on the surface like algae mats. However, you can grab a handful and easily view the individual plants, while filamentous algae resemble tangles of wet wool.
Treatment Recommendations
Some potent pond treatments remedy both weed and algae infestations in a single product. If you need to eliminate floating weeds and floating algae mats, Airmax KnockDown Defense in a tank sprayer will be your go-to. If submerged weeds and Chara keep stealing your fishing bait, spread some Airmax EasyKlear Defense granules to wipe them all out.
Identify, Treat, and Prevent Common Pond Weeds
If identifying and treating your nuisance pond weeds still seems overwhelming, check out our Weed Control Guide and then send us a weed ID photo, or call 866-POND-HELP to speak with an aquatic weed specialist.
Read more about common pond weeds in the following related guides:
How to Send Us a Weed ID Photo
Last Updated: June 19, 2025