What's it cost you when glyphsate-resistant weeds hit your fields?

Organizers of a year-old program to inform farmers about the prevalence of this this growing problem in southern and Midwest corn, cotton and soybean fields shows that a couple common weeds, when infecting fields and spreading glyphosate resistance, can take a major bite out of per-acre profits.

• Crop Talk: Corn herbicide questions
  

In that context, participants of the Respect the Rotation program, operated in part by Bayer CropScience specialists, are working with federal officials to develop glyphosate usage guidelines to stem the spread of resistance around the country.

"Glyphosate-resistant marestail costs soybean growers an added $11.50 per acre," says associate professor of weed science at the University of Arkansas and a key member of the Weed Science Society of America (WSSA) Jason Norsworthy, who is working with the Environmental Protection Agency to develop guidelines for proper resistance management practices. "Glyphosate-resistant Palmer pigweed costs cotton growers $19.45 per acre. Resistance is impacting land values, conservation tillage and more. The system, the way it is currently set up, is not sustainable."

What's this mean at the farm level? One way Bayer officials are taking action is changing the company's herbicide labels to include more clear mode-of-action labels.

"If growers can see the numbering system associated with various chemistries and easily identify what mode of action they're applying, they can better identify opportunities for herbicide rotation," says Andy Hurst, product manager for Bayer CropScience. "Without that knowledge, it is easy to apply the same mode of action over and over, encouraging the development of resistance."