re: Lawn Burweed in grass

I usually only use it in the spring to clean up anything in my carpetgrass that my pre emergent (prodiamine) didn't catch. The lable on msmturf says not to use in temperatures above 85 degrees or damage to the grass can occur. My front yard is st Augustine so i will use Celsius on it once temperatures get high but it cant be used on carpetgrass.