Figure out the area that the watershield is covering and apply the Ecomazapyr at the rate of 2-4 pints per acre, and mix in the surfactant at the rate of .16 to .64 fl. oz. per gallon of tank mix.

If you mix the solution too strong (more is NOT better when it comes to herbicides to control plants) you can shock the plant and it basically shuts down, NOT translocating the herbicide to the roots where it's supposed to go to kill the plant vs. just giving it a haircut. You did the correct thing, applying it in the Fall when the plants were taking nutrients down to the roots for the winter.

What rate did you mix it at and spray it at?

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).