I want to compost my grass clippings. Although I have never treated my grass, how can I know if the previous owner treated the grass? I bought my house 4 years ago. Presently, my yard has plenty of dandelions and other various weed. Previous posts mentioned that if persistent herbicides are present, dandelions would not grow. So can I assume any non-persistent herbicides in my grass/soil (if any) can be broken down with a nice hot compost?