Is the creeping primrose the Jussiaea repens?
I looked up Parrot Feather and it looks nastier than the primrose (i.e. worse to control and spreads further into the water).

What do you use to keep the primrose under control (keep it contained to the areas that you want it)?

www.hoosierpondpros.com

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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).