Mark VanGessel, Extension Weed Specialist; mjv@udel.edu
E3 soybeans are bred to be resistant to 2,4-D choline (Enlist), a special formulation of 2,4-D developed to minimize volatility. Meaning that these soybeans will not be injured when treated with 2,4-D choline at rates that would effectively kill conventional soybeans; and once the spray has landed on leaves and soil surface, the chance of it volatilizing and moving off-target is very unlikely. However, there is still a chance of this product drifting; or moving with the wind and air patterns created by the sprayer. So be sure to follow label instructions on the proper nozzles, environmental conditions, application techniques, and buffers to prevent injury to sensitive plants.
E3 soybeans are also resistant to glyphosate and glufosinate (Liberty). Enlist should be tankmixed with either of these herbicides to improve overall weed control and help with resistance management. Enlist Duo is a formulation of Enlist plus glyphosate. Liberty plus Enlist has been a more effective treatment for larger weeds than Enlist plus glyphosate. The three-way mixture of Enlist, glyphosate, and glufosinate is an option if the weed spectrum requires all three.
There is a potential for reduced grass control when Enlist is tankmixed with glyphosate or postemergence grass herbicides like clethodim (Select), sethoxydim (Poast), and quizalofop (Assure II). Increasing the rate of the grass herbicide can reduce the chance of this occurring, but it is not consistent. The best option is to make separate applications, particularly if the grasses are large.
Enlist, glyphosate and glufosinate provide little to no residual weed control and so if Palmer amaranth is an issue, including a residual herbicide such as Dual, Warrant, or Zidua maybe needed.