I wouldn't - no experience or training. Try a search for cattails (you may well want to narrow the results by adding control) in the "Aquatic Vegetation" categories, "Questions & Observations", and maybe "Help". There should be a lot of threads on chemical cattail control. I know there have been one or two within the last month

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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