Can clippings or other yard wastes treated with pesticides be put in the compost pile?
No simple answer exists to this question. Individual pesticides react in different ways and break down under unique conditions. Research is being conducted to better evaluate the fate of pesticide products once applied to turf areas. Lawn clippings treated with a herbicide (weed killer) should be returned to the lawn for two or three mowings after the application before using them in a compost pile. Herbicides commonly used on home lawns persist in the soil from less than one month up to 12 months, depending on the chemical. If some treated clippings are mixed into a compost pile, they will decompose more rapidly in a properly maintained pile than in soil. In general, plant material in contact with insecticides registered for home use is safe to use in a compost pile. Insecticides sprayed on plant material break down rapidly in light, and the plant material usually can be used in the compost pile within one week of application. Fungicide-treated material should also be kept out of the
