Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Bushy Pondweed

The pond dude told me at a seminar that I have bushy pond weed. Since I had just stocked it with 10 pounds of bluegil I bought 10 pounds of Talapia. (May) Now the pond weed is taking over. I purchased 2.5 gal. of AQUATHOL K. The instructions are greek to me. My pond is shared by three homeowners, but they look to me to take care of the pond(they help pay for the chemicals, but not the fish.) I tried a half gal. in 7 gal. of water in a 15 gal. spray rig. I only sprayed a 4' by 30' area and the results are not promising. Any suggestions on the amount of Aquathol/ water for application? The area I sprayed was about 1.5 average depth.

D.thompson

How many days have elapsed since your initial treatment?
If less than 5-8 days, it isn't likely that visible results have occurred at this point.
If more than 5-8 days have elapsed, and no change has occured, there are two probable causes for the poor results.
1) I'm guessing you applied the mixture to the water's surface. Subsurface injection is much preferred with Aquathol K - or any other contact-herbicides.
2) Treating narrow bands with Aquathol K for submersed weeds is usually doomed to fail due to rapid product-diffusion into adjacent (untreated) areas - and further worsened by any wind or thermal-induced currents. Assume the liquid herbicide will disperse in the same manner as a dye. If a dye applied to the targeted area isn't likely to remain somewhat stationary for 24-48 hours ("contact-time"), then neither will the Aquathol K; and efficacy will be minimal.
BTW: The dilution-ratio of Aquathol K in your spray-tank is irrelevant. The actual amount of product (not mixture) applied into a given area (based on depth) is the most critical factor (ie. achieving a plant-lethal ppm concentration). The water (diluent) used in the sprayer's mix-tank serves only as a "carrier", and simply gives you more time and fudge-factor during the application process.
Ultimately, treating BPW in Aug is a dicey proposition. Treat too small of an area, and acceptable results are unlikely due to rapid product-diffusion. Treat too large of an area, and dissolved-oxygen problems are likely.

Thank you. I treated the neak of the creek comming into the pond. There is a deep area about 40 feet back up the creek that is full of bluegil and bass. Before I teated that area, I wanted a clear path into the pond proper. (narrow band)
I did spray the Aquathol on the surface, but I appreciate the advise about putting it under the surface. I did not see that in the instructions. I am trying to treat 1/3 of the ppond at a time to keep from killing the fish. I do have an air pump and air stones circulating the pond water. But I do not want to kill the bass.

Good news, after about two weeks it just turned loose and floated out into the pond. I treated the deep area of the creek and it responded quicker. It has rained some in the last week and a lot tonight, so I will hold off treating the pond proper until the flow slows down. My pond flows over the damn into Lake Waxahachie so I try to be careful about run off. The pond look a lot better, but the rain usually "beats down" the problems and appears to clear up for a few days...

Excellent d.thompson. There is a real sense of satisfaction in fixing a pond problem.