Both of the two most commonly-used herbicides in no-till are under fire.

Glyphosate has been under fire due to thousands of non-ag lawsuits being filed against Bayer, who inherited many of these concerns when they purchased Monsanto in 2018. In addition, the U.S. Environmental Protection Agency (EPA) has recently taken steps to crack down on the use of atrazine.

Our annual No-Till Operational Benchmark Study shows nearly two-thirds of no-tillers use atrazine and glyphosate to control weeds in no-tilled corn. Some 83% of growers use glyphosate with no-tilled soybeans.

Where’s the Science?

EPA announced in late June that it expects to revise its atrazine registration based on reducing chemical runoff levels. In 2020, EPA set the atrazine aquatic ecosystem concentration equivalent level of concern (LOC) at 15 parts per billion for water in streams, but is now proposing an ultra-low atrazine level of only 3.4 parts per billion. This label revision would have a devastating impact on no-tillers.

The proposed rules would dramatically reduce atrazine application rates or even totally prohibit application in some watersheds. The EPA annual rates would be restricted to 2 pounds of active ingredient or less per acre for sorghum, field corn and sweet corn.

The rules would prohibit atrazine application when soils are saturated or above the soil’s ability to retain water. Application could also be prohibited during rain or other storm events that are likely to produce runoff or — get this — even when forecasted within 48 hours of application. In addition, atrazine could no longer be applied aerially.

Need More Time

In mid-summer, several ag groups asked EPA to extend the public comment window by another 60 days past the current September 6 deadline.

These herbicide formulations are essential for effective weed control in many no-tilled fields. So it’s in your best interest to let ag groups and Washington politicians know what the serious consequences could be if these proposed rule changes make it much tougher to control weeds in your no-till fields.