Paul from Cordele writes
Image Herbicide for St. Augustine Grass and Centipede Grass is not labeled to treat dallisgrass. Unfortunately there are no products available that will kill the Dallisgrass without killing the surrounding St. Augustine grass. The best option once it has emerged is to either spot spray or wipe on something like Round Up Quick Pro, or hand dig up the clumps of dallisgrass down to the root system and re-seed.
Answer last updated on: 09/12/2019