Thanks for your question Joe, At Hewitt’s, we sell a product made by Bonide called Weedbeater Plus Crabgrass and Broadleaf Weed Killer. Follow the directions on the package and you’ll wipe out the nutsedge as well as some other unwanted weeds without harming the grass. Never apply weed killers when temperatures are expected to go above 85° or it may burn the lawn. September is a great time for weed killing.