I have the same grass looking plant popping up in my pond this year as well. I did throw out some wild rice seed last year, but never saw any of it. I wonder if the seed could stay dormant in the pond for a year?

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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).