Here is some information from Dr. Eric Prostko, UGA Extension Agronomist – Weed Science.
First, let me remind you that Halex GT is a postemergence field corn herbicide from Syngenta that many Georgia growers use. Halex GT is a pre-mixture of the following active ingredients: mesotrione + glyphosate + s-metolachlor. In 2025, many growers have figured out that they can make their own version of Halex GT for much less money ($$) using generic formulations of these same active ingredients. However, the big issue is that the s-metolachlor in the Halex GT is not exactly the same formulation as in the generic products. Thus, there could be some problems with increased corn injury and perhaps even physical compatibility with a home-made mix. In fact, it clearly states on the labels of mesotrione (if you look for it) that there can be some enhanced crop injury when mixing mesotrione with other emulsifiable concentrate (EC) herbicide formulations such as Dual Magnum (s-metolachlor) or Outlook (dimethenamid-P). I have talked to just a few folks who have made their own Halex GT without any major issues except where overlapping occurred. However, since I have no personal research to support this practice, I am not recommending growers make home-made Halex GT at this time. I am in the process of conducting a field trial this summer to address this research issue and reserve the right to change my position in 2026. Here is a quick summary of what I just discussed:
2) Do early postemergence applications of Cobra (lactofen) in soybeans increase yield?
The short answers is HELL NO! This is a myth that has been permeating around the high-yield grower community for years. There have been several replicated field studies to show there is absolutely no evidence to support this claim. Please check out this recent white paper (December 2024) from the Mississippi Soybean Promotion Board to access the data summary:
https://mssoy.org/sites/default/files/2024-12/LACTOFEN%20YIELD%20WHITE%20PAPER%20DEC%202024.pdf
