A recent trial by the University of Minnesota showed that using a preemergence (pre) herbicide in soybeans is beneficial, offering a significant reduction in weed densities early in the season. Weed escapes at the end of the season were nearly eliminated when using a pre herbicide, as well.
Although the planting season has been off to slow start for many across the state this year, growers are encouraged to follow through with plans to apply a pre herbicide. This is particularly important in fields where herbicide-resistant weed populations are present or suspected. An effective pre application can go a long way in helping control a problem weed population, especially when postemergence herbicide options are limited or limited in effectiveness.
The trials did not see a yield increase when using a pre, but long-term benefits of increasing herbicide diversity and limiting weed seedbank replenishment should not be ignored.
Use of a pre herbicide with residual activity also helps control weeds, such as waterhemp, that emerge over an extended period of time. Producers should also have a wider window to make a postemergence herbicide application when a PRE herbicide is used.
Read more about the benefits of using pre herbicides in soybeans from the U of M.
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