There's a local wetland that was dry for 2 years. It filled with water last year and it's covered with lilies in a year. I'm talking about an area that is probably 20+ acres. It gets cold enough for the ground to freeze up here. I'm amazed at how hardy they are.

I think chemicals would be the route to take.

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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).