This is reminder that the only two labeled formulations of 2,4-D that can be applied postemergence in 2,4-D-resistant soybean varieties are Enlist One and Enlist Duo. No other salt formulations and no ester formulations can be applied postemergence to these varieties. Ester formulations are more volatile than salt formulations and volatility can increase with the warmer air and soil temperatures that typically occur when postemergence applications are made. A bill to ban the sale and application of 2,4-D ester formulations has been introduced in the Illinois legislature multiple times; applying an ester formulation postemergence in soybean could result in additional damage to nontarget vegetation (i.e., trees, ornamental plants, etc.) and increase the likelihood that this bill will advance through a future legislative process.

Hager, A.. “A Reminder about 2,4-D Formulations.” Department of Crop Sciences, University of Illinois at Urbana-Champaign, March 7, 2025.