Volunteer corn costs

Published on: 16:06PM Jun 08, 2010
Gordon Vail
What problem weeds concern you most in soybeans? Is volunteer corn on your list? 
This season, chances are that most of the volunteer corn in your soybean fields is glyphosate-tolerant. Since glyphosate won’t control it, you will want to add another mode of action to your soybean herbicide program.
Here are a few reasons to be on the look out for volunteer corn in 2010:
  • Purdue University studies have shown that just 0.5 volunteer corn plants/m2 – an area roughly the size of a hula-hoop – can cause a soybean yield loss of 6.5 bu/A1.
  • The wet fall in 2009 caused a late harvest in many areas. That usually means more ears fell, likely leading to increased volunteer corn populations in 2010.
Uncontrolled volunteer corn can also serve as a trap crop for adult corn rootworm beetle, increasing the potential for egg-laying in soybean and heavier corn rootworm pressure when you rotate back to corn.
1P. Marquardt and W. Johnson, Purdue University trials conducted in 2008 and 2009