More adverse spring weather and the northern spread of herbicide-resistant marestail find more reduced-tillage farmers considering fall residual herbicide applications. “Fall applications have risen dramatically in the last few years and will continue to grow,” says Regan Wear, CHS agronomy manager in Shipman, Ill. “Erratic, wet, cold springs have narrowed the planting window and fueled interest in fall residual herbicide applications because they really sharpen up timing the following spring.”

Key to the fall residual herbicide application decision is to determine whether these applications’ yield and income contributions will offset the investment.

Tangible ROI

These factors may contribute to the yield and profit impact of fall residual herbicide applications

  • Planting earlier in warmer, cleaner seed beds
  • Reduced need/expense for spring burndown herbicide applications
  • Reduced weed competition
  • Decreased SCN and black-cutworm damage from controlling alternate host weeds.

 “The return on investment from fall applications comes from the ability to plant early,” Wear says. “Winter annuals (see sidebar) can create a salad bowl that’s really hard to get through and can force extra tillage passes to get the weeds down.

“Fields sprayed in the fall are our first fields planted and could see a 20% increase in yields compared to corn planted later.”  “Farmers invest so much in seed today,” says Jeff Carpenter, DuPont Crop Protection corn herbicide portfolio manager, “that $12-$15 spent in the fall can result in better spring weed control and earlier planting so that the seed has greater opportunity to achieve its genetic potential.”

Long-term, fall residual herbicide applications can help protect the productivity and land values by preventing herbicide-resistant weeds’ establishment. Fall residual herbicide applications can also add an additional site of action to resistant weed-management programs, Carpenter adds.