- Federal Environmental Protection Agency (EPA) announced a June 12th or V4 growth stage cutoff in Illinois, Iowa, Indiana & Minnesota still allowing growers an additional weed control option in dicamba tolerant soybeans.
- Reminder that all new label restrictions follow the label restrictions that were in place in states that sought a 24 (A) label in the previous year.
- Fields that don’t get an application of dicamba, still have options for weed management.
The EPA has reduced the application cutoff date from June 30th to June 12th in Illinois, Iowa, Minnesota, and Indiana. The deadline is June 12th, however, keep in mind the federal label also states that applications can be made to soybeans prior to V4 growth stage (four fully expanded trifoliates on the main stem) whichever comes first. For Minnesota, the application date is June 12th for soybeans grown south of Interstate 94, and June 30th north of Interstate 94. Minnesota also added a state-wide temperature restriction; if the daytime high temperature is predicted by National Weather Service to be higher than 85°F or if at the time of application is 85°F or warmer. Lastly, South Dakota also has a June 20th cutoff, or V4 growth stage whichever comes first. Be cognizant of state specific regulations that are still in place. For example, if your state had a temperature cutoff last season, that cutoff is still in place in addition to the new date and/or growth stage cutoff on the federal label.
To make successful applications of the three approved products, there are several best management practices to follow: approved nozzle selection, utilizing an approved volatility reduction adjuvant (VRA) and drift reduction adjuvant (DRA) for all applications. Applicators must closely monitor the weather, and closely monitor the landscape prior to applications for susceptible crops/species.
Dicamba is still a great addition to glyphosate to provide burndown on a variety of broadleaf weeds include tough-to-control weeds like marestail. Burndown applications of dicamba also allow for dicamba tolerant soybeans to be planted without a plant back restriction, making it more appealing to a no-till operation. Once dicamba is no longer a viable option to use, glufosinate (Liberty®) is an option for soybeans that contain the XtendFlex® trait. Other options that can be used are the foliar applied PPOs, however, those products along with glufosinate will need to be applied to small, actively growing weeds with increased carrier volume to provide adequate coverage (nozzle selection is important) on the target weeds. Products should also be checked for a planting interval for the following seasons crop to mitigate the risk for carryover.
As plans are in place for the 2023 growing season, keep in mind that dicamba is still an effective tool for weed management, but it must be stewarded to coexist with other technologies and specialty crops. If you have questions regarding label changes to dicamba products, contact your local FS Crop Specialist.