Although glyphosate resistant weeds have been documented in states surrounding Iowa, at this time our only confirmed glyphosate-resistant species is horseweed/marestail (Conyza canadensis). However, over the past decade we have selected for a weed spectrum that possesses a higher level of tolerance than was present at the start of the Roundup Ready era of weed management. Because of this, glyphosate control failures are more common now than they were ten years ago.
Iowa State University
Hartzler, Robert G., "Improving glyphosate performance in Roundup Ready soybean" (2008). Integrated Crop Management News. 805.
The Iowa State University Digital Repository provides access to Integrated Crop Management News for historical purposes only. Users are hereby notified that the content may be inaccurate, out of date, incomplete and/or may not meet the needs and requirements of the user. Users should make their own assessment of the information and whether it is suitable for their intended purpose. For current information on integrated crop management from Iowa State University Extension and Outreach, please visit https://crops.extension.iastate.edu/.