In many areas fall herbicide applications were delayed due to the late harvest. Applications can still be effective, depending on weeds present, temperature, rate of herbicide and additives used. The article offers recommendations for these late-fall applications and their importance, particularly for control of herbicide-resistant marestail.
This week growers facing challenges with Palmer amaranth questioned whether it was due to the product, the environment and lack of rain, or a resistant weed. Several factors could be at play, notes a UNL weed scientist, who recommends starting with preemergence herbicides with residual activity to get the best control.
With cold, wet conditions in March, many producers may be facing a smaller than expected window for making their herbicide burndown applications in April. This makes timely applications now even more important to provide for a proper interval before planting this year.
Nine weed species in Nebraska have now evolved resistance to at least one group of herbicides. Six weed species — common ragweed, common waterhemp, marestail, kochia, giant ragweed, and Palmer amaranth — have confirmed resistance to glyphosate. Rotate herbicide sites of action and weed control practice to avoid contributing to this trend.