David from Fort Collins, Co writes
The manufacturer says "Do not use clippings as mulch or compost around flowers, ornamentals, trees, or in vegetable gardens" After an application, when is it safe to again use grass clippings as a mulch?
When using Drive XLR8 Herbicide Crabgrass Killer the active ingredient quinclorac has dissipation values that can range from 60 to over 500 days. Because quinclorac does not bind well to soil, some dissipation noted in field testing could be due to chemical testing. The persistence hazard of quinclorac is rated high (likely to take over 60 days to degrade to half of the applied concentration). We would recommend waiting an entire season before using any grass clippings as mulch.
Answer last updated on: 06/30/2022
