Aquathol K at 3 ppm is effective at controlling naiad. This would be 1.9 gallons per acre foot. For example, 1 acre, 5 feet deep would need about 10 gallons. I would suspect in your area the cooler (cold) weather would result in most of the biomass falling out. Next year I would wait until you feel you can't wait any longer and then do a treatment to control the bulk of the area where the naiad is. You should get some residual control outside of the "target" area by treating this way.
Send me an IM if you have any questions.
