I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
There is not a good control for Bahia that won't harm centipede. Since the Bahia gets taller you can conceivably use a wiper applicator to get glyphosate (Rounup is one brand) on the Bahia but not on the centipede. Not easy, but an option.
Thanks for the question. Please stop in again soon!
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