Dry Midwest Spells Trouble for Weed Control

Farmers across the Midwest are facing challenges with weed control as lingering dry conditions from last year, coupled with a dry spring, threaten crop yields. The lack of moisture has several repercussions:

• Reduced Herbicide Effectiveness: Residual herbicides, a key component of weed management, rely on adequate moisture to activate and work effectively. Dry spells hinder this activation.
• Herbicide Carryover: Dry conditions can increase the risk of herbicide carryover from the previous season, potentially damaging sensitive crops like soybeans.

Adapting to the Challenge Experts like Kevin Bradley, weed scientist at the University of Missouri, and Gentry Sorenson, agronomist at Iowa State University, urge farmers to be proactive:

• Soil Bioassays: Collecting soil samples to test for herbicide carryover allows adjustments to planting practices.
• Strategic Tillage: While disrupting no-till systems is less desirable, tillage can help dilute carryover herbicides in some cases.
• Delayed Planting: Fields with the highest carryover risk might benefit from a later planting window.

Other Weed Threats Regardless of weather, waterhemp remains a constant threat, requiring full herbicide rates and timely application. Additionally, experts warn of emerging pasture weeds:

• Fountain Grass: An increasingly troublesome invasive species with spiny stems that cattle avoid. Spot-treating with glyphosate is recommended.
• Knotroot Foxtail: This perennial invader resembles yellow foxtail but is less desirable for livestock and harder to control.