Answer: Roundup is quite effective in killing bermudagrass, but will kill other green plant tissue it contacts. It ties up in the soil and breaks down quickly so you can replant within 10 days to 2 weeks. It is most effective on actively growing bermudagrass. On dormant or drought-stressed bermudagrass it is not very effective. Therefore, you will need to wait until grass resumes vigorous growth for it to be an effective control. Repeat applications are usually needed as there are always a few weeds that escape or seeds that germinate later.
A non-chemical option for significantly reducing bermudagrass infestations is summer rototilling. When you rototill the grass must use stored energy to resprout, and runners brought to the surface by rototilling will dry out in the hot summer sun and die. After rototilling, wait a week or so to allow resprouting and then rototill again. It is important that you do this in the hot, dry summer period. I have seen bermuda virtually eliminated by diligent application of summer rototilling.
Good luck and thanks for the question!
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