Herbicide-resistance issues have soybean farmers walking their fields across the county, scouting for weeds. Stevan Knezevic, Ph.D., weed scientist at the University of Nebraska-Lincoln, answers some common questions he hears from farmers.
Q: Why should I change my weed-management program if I don’t have a resistant-weed problem now?
A: Over the last 10 years, the glyphosate-resistant weed populations have expanded at about a rate of one weed per year. If your fields are free of resistant weeds no, that doesn’t mean that you will not have any next year. The costs of managing a resistant weed population can greatly outweigh the costs of preventing it from the start.
Q: Can I just use different brands of glyphosate or add different adjuvants or surfactants to the glyphosate I normally use to control or prevent resistant weeds?
A: No. Glyphosate is still the same in all brands, thus changing brands will not do any good. To prevent herbicide resistance, you must use products that have different or multiple modes of action.
Q: How can I tell if I have resistant weeds?
A: Scout your fields after a herbicide application and look for survivors. If you see weeds that survived a herbicide application, that could be a sign of potential resistance. There are 143 weeds that have shown resistance to herbicides in the United States, and you can learn more about the most threatening ones and how to identify them at www.TakeActionOnWeeds.com.
Q: What will using all these different herbicides cost me?
A: The cost of preventing resistance is not as high as the cost of getting and fighting resistance in our field, or yield loss resulting from uncontrolled resistant weeds. Weeds cost. Proactive management pays.
Q: When will a new herbicide be commercialized that will solve this problem?
A: There is no new herbicide to solve this problem. Farmers should not wait for a new herbicide to be the simple solution for resistant weeds. Take action now. Know your weeds. Understand field management practices that give your crops the upper hand against resistant weeds. And understand how to best select herbicides with diverse sites of action to control weeds.
- See more at: http://unitedsoybean.org/article/herbicide-resistance-faq/#sthash.pUfihdqB.dpuf
Herbicide-resistance issues have soybean farmers walking their fields across the county, scouting for weeds. Stevan Knezevic, Ph.D., weed scientist at the University of Nebraska-Lincoln, answers some common questions he hears from farmers.
Q: Why should I change my weed-management program if I don’t have a resistant-weed problem now?
A: Over the last 10 years, the glyphosate-resistant weed populations have expanded at about a rate of one weed per year. If your fields are free of resistant weeds no, that doesn’t mean that you will not have any next year. The costs of managing a resistant weed population can greatly outweigh the costs of preventing it from the start.
Q: Can I just use different brands of glyphosate or add different adjuvants or surfactants to the glyphosate I normally use to control or prevent resistant weeds?
A: No. Glyphosate is still the same in all brands, thus changing brands will not do any good. To prevent herbicide resistance, you must use products that have different or multiple modes of action.
Q: How can I tell if I have resistant weeds?
A: Scout your fields after a herbicide application and look for survivors. If you see weeds that survived a herbicide application, that could be a sign of potential resistance. There are 143 weeds that have shown resistance to herbicides in the United States, and you can learn more about the most threatening ones and how to identify them at www.TakeActionOnWeeds.com.
Q: What will using all these different herbicides cost me?
A: The cost of preventing resistance is not as high as the cost of getting and fighting resistance in our field, or yield loss resulting from uncontrolled resistant weeds. Weeds cost. Proactive management pays.
Q: When will a new herbicide be commercialized that will solve this problem?
A: There is no new herbicide to solve this problem. Farmers should not wait for a new herbicide to be the simple solution for resistant weeds. Take action now. Know your weeds. Understand field management practices that give your crops the upper hand against resistant weeds. And understand how to best select herbicides with diverse sites of action to control weeds.