Protect Corn at Its Most Vulnerable Stage

protect corn

Herbicide applications that provide control of emerged weeds and prevention of new weeds protect corn at its most vulnerable stage, just after emergence.

Early in the growing season, shortly after emergence, corn plants are just beginning to put down their roots. At this stage, their demand for nutrients, water and light is small, so resources are plentiful and small weeds are noncompetitive. From a distance, corn plant development appears to be off to a great start, but these young plants are at their most vulnerable. Though not directly competing with weeds for resources at this stage, corn can sense the presence of and have noncompetitive interactions with even the smallest of weeds, negatively affecting corn growth, development and yield potential.

Corn plants are most sensitive to nearby weeds during the first week of postemergence, even when they are only a few inches tall, and can detect changes in light quality when sunlight is reflected off nearby weeds.  As soon as a corn plant detects the presence of a weed, it will engage in a shade avoidance response, reallocating resources to elongating and growing taller in order to overshadow nearby weeds, neglecting whole plant development. The roots often suffer the most in this scenario, as they are smaller and poorly developed. The poor nutrient uptake that results can lead to poor grain fill, lower quality and reduced yields.i

“Corn yields can be affected as soon as weeds emerge from the ground,” said Frank Rittemann, selective corn herbicides product manager at Bayer. “Early season weed control is necessary to protect corn from both competitive and noncompetitive interactions at its most vulnerable stage.”


Bayer solutions for weed management 

Protect your corn when it is most vulnerable by taking a zero tolerance approach and controlling weeds before they go to seed. Rittemann recommends using a two-pass herbicide program of Corvus® tankmixed with atrazine, followed by DiFlexx® DUO tankmixed with  Roundup PowerMAX®.

Corvus, tankmixed with atrazine, provides overlapping sites of action for control of weeds pre-emergence. With as little as a half-inch of rain, Corvus reactivates to wipe out tough, resistant weeds. “Corvus kills weeds before they are out of the ground and takes out any weeds that have already emerged,” said Rittemann. “This minimizes the weeds that emerge with the corn plants and gives them an early start on acquiring nutrients before they engage in any shade avoidance response due to weeds.”

DiFlexx DUO, tankmixed with Roundup PowerMAX, takes down tough-to-control, resistant weeds postemergence. “With multiple, powerful and effective sites of action, this postemergence application works best if applied soon after emergence to take weeds out at three inches or less,” Rittemann said. 

When used as part of a zero tolerance, two-pass herbicide program, Corvus and DiFlexx Duo effectively take out and control tough weeds to protect corn at its most vulnerable.  


©2018 Bayer Group. Always read and follow label instructions. Bayer, the Bayer Cross, Corvus, DiFlexx, and Roundup PowerMAX are trademarks of Bayer Group. Atrazine and Corvus are restricted use pesticides. Not all products are registered in all states. For additional product information call toll-free 1-866-99-BAYER (1-866-992-2937) or visit our website at www.CropScience.Bayer.us. Bayer CropScience LP, 800 North Lindbergh Blvd. St. Louis, MO 63167.

Work Cited

i Hartzler, B. “Protect Your Corn Yields from Weeds.” Iowa State University Extension and Outreach: Integrated Crop Management News, 2010. https://crops.extension.iastate.edu/cropnews/2010/05/protect-your-corn-yields-weeds

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