Travis Gannon and Fred Yelverton As previously mentioned on Turffiles, oxadiazon was under registration review by the United States Environmental Protection Agency (US EPA) and their proposed interim decision was released in August 2021, you can read our information on the proposed changes. The proposed interim decision would have restricted applications to golf course fairways and sod production while eliminating applications to sports fields. The US EPA released the registration review decision in March 2022 which contains the following changes: 1 – Oxadiazon will continue to be registered for use on golf courses, sports fields, sod production and parks (with restrictions noted below). 2 – Oxadiazon applications will require post-application irrigation on all use sites as soon as possible on the same day of application. 3 – All herbicide products including oxadiazon will become restricted use pesticides for use by certified applicators only (or persons under their direct supervision). 4 – Single maximum application rate will be 3 lb active ingredient per acre with maximum annual application rate of 6 lb active ingredient per acre from all formulations. However, heavy weed pressure scenarios on golf courses will be allowed to use 4 lb active ingredient per acre (per application) with maximum annual application rate of 8 lb active ingredient per acre. 5 – Oxadiazon use will be limited to 30% of all golf course turf area (including roughs, fairways, tees and greens. 6 – Liquid applications on golf courses, athletic fields, parks, etc. will be limited to a single application per year with a maximum application rate of 3 lb active ingredient per acre. 7 – All oxadiazon applications (including sod farms) will require a 10-feet wide nontreated vegetative buffer from any surface water feature. 8 – Liquid backpack applications will be limited to spot treatments only. 9 – Mechanically pressurized handgun applications will be prohibited in all use sites except golf course turf. For complete details, please visit the specific US EPA docket.