Published on:
17:46PM Jun 08, 2009
Purdue University, Ohio State University and Southern Illinois University recently shared data from a joint 2007-08 glyphosate-tolerant corn timing study. The findings reinforced what many weed scientists (including me) recommend – controlling weeds early in the season protects yield. For example, Iowa State University reports a one day delayed application of glyphosate may cost more than a pre-emergence residual herbicide, depending on crop price and yield potential.

In the study:
- Plots treated with foundation herbicides early in the season performed better than post-only applications.
- The longer weeds were allowed to compete with corn, the less it yielded.

Corn growers across the Midwest use pre-emergence herbicides for a variety of reasons, including better weed control, yield protection, a wider application window, and to control key problem weeds. How have pre-emergence herbicides protected your crop so far this season?
keyword:
Keyword