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Latest university data continues to confirm the importance of early-season
weed control in corn

New research from a glyphosate-tolerant corn timing study conducted in 2007 and 2008 by Purdue University, Ohio State University and Southern Illinois University continues to prove the value of early-season weed control.

The data shows plots treated with foundation pre-emergence herbicide treatments early in the season performed better than post-emergence only applications against foxtail and giant ragweed and resulted in the highest yields.

In the study, plots were treated with different pre-emergence programs � atrazine, Bicep II Magnum® (atrazine + S-metolachlor) and Lexar® (atrazine + S-metolachlor + mesotrione). Weed control evaluations were taken prior to a post-emergence glyphosate application for three different timings: applying glyphosate at 12-inch corn, applying glyphosate one week after 12-inch corn and applying glyphosate two weeks after 12-inch corn.

Weed Control
For the two weeds tested, foxtail and giant ragweed, using a foundation pre-emergence program provided better weed control, leading to increased yields. Atrazine alone provided some weed control, however Bicep II Magnum provided better weed control and Lexar provided the best level of control.

Foxtail Control

Giant Ragweed Control

Corn Yield

Corn Yield

The weed control graphs show the percent control of each weed at each of the three different post-emergence glyphosate applications. Comparing the same treatments at each different timing interval, each of the pre-emergence applications improved weed control and Lexar performed most effectively. When you evaluate the yield graph, the value of early-season weed control is clear.

The longer the weeds were allowed to compete with corn, the less corn yielded. The plot treated with Lexar pre-emergence followed by a glyphosate application at 12-inch corn yielded 223 bushels per acre compared to 211 bushels for the Lexar plot treated with glyphosate at two weeks after 12-inch corn.

The difference is even more dramatic when you compare to the plot that didn�t receive a pre-emergence herbicide treatment. Three different plots received no pre-emergence treatment; instead, the plots received one shot of glyphosate at each of the three different timings. The plot that received one shot of glyphosate at 12-inch corn yielded 204 bushels per acre, compared to 223 bushels for the Lexar-treated plot followed by one shot of glyphosate at 12-inch corn � a difference of almost 20 bushels per acre.

Bottom Line
Don�t save quarters now to lose dollars later. Use Lexar, Lumax®, or Bicep II Magnum pre-emergence corn herbicides to protect corn fields from yield-robbing early-season weeds, which, in turn, will protect yield potential and your bottom line. It�s simple, ask your retailer or Syngenta sales representative which solution is right for your farm.

Click here for a downloadable sell sheet.


©2009 Syngenta Crop Protection, Inc., P.O. Box 18300, Greensboro, NC 27419.

Important: Always read and follow label instructions before buying or using these products. Bicep II Magnum®, Lexar® and Lumax® are Restricted Use Pesticides.

Bicep II Magnum®, Lexar®, Lumax®, the mesotrione logo and the Syngenta logo are registered trademarks of a Syngenta Group Company. Roundup OriginalMAX® is a registered trademark of Monsanto Technology LLC.

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