Continued Wet Weather Conditions Could Affect Applying Preemergence Herbicides to Crops

Continued rain could mean farmers will need to apply preemergence herbicides to corn after it has already emerged
Continued rain could mean farmers will need to apply preemergence herbicides to corn after it has already emerged

According to a recent Agriculture.com article, wet weather across the Midwest and northern Plains this week could affect farmers’ ability to apply preemergence herbicides to crops. The article reports that, while much of the Corn Belt has seen favorable corn-planting weather over the past few days, planting delays are expected to continue; this could mean farmers may be forced to apply preemergence herbicides to corn after it has already emerged.


“The drier pattern across the Midwest and Delta so far this week has allowed corn and soybean planting to progress very well, while spring wheat planting has improved in the northern Plains,” says Don Keeney, senior ag meteorologist with MDA Weather Services. “However, rains should return to central Midwest, [northern Midwest, and northern Plains] over the next few days, which will slow planting there a bit.” Agriculture.com claims that the inability to apply preemergence herbicide to crops won’t necessarily indicate a season of fighting “untreated weeds”; in fact, Ohio State University Extension weed scientist Mark Loux reports many [preemergence herbicides] can be applied after the crops are in the ground.


“Most preemergence corn herbicides can be applied to emerged corn,” Loux reports, “and some of them have enough foliar activity to control small, emerged weeds without the need to add postemergence herbicides. It’s also possible to mix in some other POST herbicides such as Impact, dicamba, 2,4-D, Capreno, etc to control emerged weeds, instead of glyphosate or Liberty.” Loux warns, however, that many products have a specific window of time when they can be applied to crops.


While crop planting conditions have improved over the past few days, Agriculture.com reports wet weather could impact the timing of applying preemergence herbicides to crops.