I stumbled upon these this morning I tried Googling a bunch of different pictures of Polaris grass and couldn't find a match I thought maybe this might be worthy of a future extraction

I’m not an expert by any means but it doesn’t look like Phalaris grass, especially the types that are of interest here (Arundinacea, Aquatica and Brachystachys). I’m not sure what genus that plant you found belongs to however I am pretty confident in saying it’s not a grass from the Phalaris genus.