Cattails grow dense enough to provide habitat for mosquitos to breed, tight enough so that small fish that eat mosquito larvae cannot easily swim in the water to eat the larvae. If it was my pond, I would remove every cattail.

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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).