Catt Plex is a glyphosate herbicide labeled to kill shore and emerged aquatic weeds such as cattails all the way down to the root as well as thousands of grass and broadleaf weeds in turf, but will not target algae. You may consider using Crystal Blue Copper Sulfate which controls most species of algae like filamentous or string algae with very low concentrations of copper sulfate. Please refer to the product label to confirm it can be used in for your treatment area, and for complete application instructions.
Catt Plex is not labeled for American pond weed. We would recommend SePRO Sonar RTU Aquatic Weed Herbicide is a specially formulated aquatic herbicide that’s designed to help control troublesome weeds in ponds. It’s very easy to use, simply pour it directly into the water from the shoreline without the need for boat or spray equipment and it also doesn’t require any mixing. There are NO fishing, swimming, livestock and pet consumption restrictions for Sonar RTU.
Catt Plex will only kill the cattails that are sprayed directly, this will not control or prevent regrowth from submerged weeds. Repeat treatments may be necessary to control weeds regenerating from underground parts or seed.
Page 14 of the product label for Cattails: For broadcast applications, apply 4 ½ to 6 pints per acre as a broadcast spray or at a ¾% solution with handheld equipment (Refer to the chart on page 9).
For best results, applications should be made as a broadcast application or spot treatment with the addition of a Non Ionic Surfactant for best results in accordance with the product label.
