Herbicide Resistance Management

Updated: July 25, 2018

Current Situation

Herbicide resistance is one of the biggest issues facing U.S. farmers. Without the use of herbicides to control weeds, North American soybean and corn farmers would lose half their crop, costing them approximately $43 billion every year, according to the Weed Science Society of America.

Many farmers now realize that managing existing herbicide-resistant weeds and preventing the development of new ones requires complex weed-management strategies. Farmers must adopt weed-management practices that lessen the impact of herbicide-resistant weeds and protect current and future herbicide technologies. A diversified weed-management plan that includes using multiple herbicide sites of action and non-chemical controls – like cover crops, tillage and hand weeding – keeps weeds under control and stewards herbicide technology.

Safeguarding existing technology is crucial to weed-management. It’s been more than a decade since any significant new herbicide chemistries were established, and no new sites of action are under development. Because herbicides take an average of 11 years to create and herbicide chemistries cost an average of $286 million to bring to market, that’s unlikely to change reports CropLife America. Maintaining the effectiveness of current products is critical to farmers’ success.

Why the Checkoff Cares

Herbicide-resistant weeds cost soybean farmers time and money, impacting their profitability. The soy checkoff encourages farmers to adopt best-management practices to preserve crop-protection technologies and enhance the overall sustainability of the U.S. soy crop.

Key Points

  • The checkoff has played a leading role in establishing the Take Action program, an industry-wide partnership helping farmers manage pesticide resistance.
  • The Take Action industry partnership includes more than 25 universities from major row-crop states around the country, eight major herbicide providers, six farmer-led commodity organizations and one industry organization.
  • The Take Action effort encourages farmers to adopt weed-management practices that lessen the impact of herbicide-resistant weeds and protect current and future herbicide technology.
  • For farmers to manage and prevent herbicide resistance on their operations, they must first understand the weeds on their farm. Knowing when weeds grow and pollinate and how to control them before they go to seed gives farmers the upper hand.
  • Soybean farmers can manage for herbicide-resistant weeds in both no-till and conventional tillage systems through the use of crop rotation, cover crops, tillage and appropriate herbicide applications.
  • University research shows using multiple herbicide sites of action provides better control over weeds.
  • Poor weed control means higher costs for soybean farmers. Soybean farmers should be aware of the cost of poor weed control. Managing the risks of herbicide-resistant weeds can help protect the long-term bottom line.

Facts & Figures

  • A soy checkoff-funded survey shows that 50 percent of U.S. soybean farmers use a proactive, diversified weed-management plan that includes actions like tillage, burndown and residual-herbicide use.
  • According to the International Survey of Herbicide Resistant Weeds, 470 resistant weeds have been reported as herbicide-resistant globally. Of these 470, the United States reported 161, more than any other country. Herbicide-resistant weeds have been reported in 88 crops in 69 countries.
  • Weeds have developed resistance to 23 of the 26 known herbicide sites of action, according to the International Survey of Herbicide Resistant Weeds.
  • Weeds with resistance to multiple sites of action are becoming more commonplace. A waterhemp population with resistance to six sites of action was recently tested and confirmed by the University of Missouri.
  • According to the Weed Science Society of America, without the use of herbicides to control weeds, U.S. soybean and corn farmers would lose half of their crop.
  • On average, it takes $286 million and 11 years to bring a new pesticide to market, according to CropLife America.

Other Resources