After a Trimec Southern spray in the first week of March, Mine was just that! Only the Centipede and Bermuda remained. I should have followed up 4-6 weeks later with another treatment! My bad! As the crabgrass came back in some areas! You have to kill the junk to let the good stuff take over! It all takes time and effort, but the rewards are awesome! The more of the bad you kill the better the good is! My centipede is slowly choking out the Bermuda as well!