By Eric Jones and Philip Rozeboom et.al
Kochia is a difficult to manage weed that infests crops across South Dakota. Herbicides are the most effective and efficient tactic to manage kochia. However, overreliance on single herbicide active ingredients (such as glyphosate [Roundup] and imazethapyr [Pursuit]) have resulted in resistant populations. Mixing effective herbicides is a tactic that can reduce selection pressure on resistant weeds and increase the effectiveness of weed management.
Dicamba (Engenia, Xtendimax, Tavium) products labeled for tolerant soybean varieties had great utility in managing herbicide-resistant kochia. However, due to the registration being pulled for these products, many South Dakota soybean farmers now have few options for effective postemergence herbicide. Glufosinate (Liberty) and lactofen (Cobra) are effective on kochia when applied timely (2 to 4” weeds). While effective, farmers are highly encouraged to not apply these herbicides alone and recurrently as to not select for resistant weeds.