What are you spraying to kill it? I bought some Atrazine but found some Image I had in a cabinet in the garage. Sprayed half the pump sprayer and then looked at the label.... "Do not use on St. Augustine"... I have St. Augustine. I am crossing my fingers I sprayed it early enough the grass was still dormant and it won't hurt it. Otherwise, its going to be a long summer trying to recover my grass.