Volunteer corn has become one of the more prevalent weeds in fields across the Midwest. Conditions experienced in 2012, however, have combined to create almost a perfect storm in some fields for potentially high volunteer corn populations in 2013.
In areas most affected by the drought of 2012, stalk quality issues may have led to increased stalk breakage and dropped ears. Grain moisture was also very low in areas, reaching 13% or less across southern MN, for example, by the end of the harvest season.
Harvesting grain at an extremely low grain moisture content can lead to increased mechanical harvest losses due to increased kernel shattering and ear droppage. These factors can lead to higher than normal volunteer corn populations the following year.
Volunteer corn not only can rob yield, but it also can impact the management of pests like corn rootworm. U of MN Extension has just published a fact sheet, "Control Volunteer Corn for Yield Protection and Corn Rootworm Management" that addresses these concerns and more.
Yield impacts, the relationship between volunteer corn and corn rootworm population development, and potential impacts on resistance to Bt-CRW traits are discussed. Control options and why it is recommended to control volunteer corn by the V4 to V5 stage are also discussed.
You can view this fact sheet at: http://z.umn.edu/volunteercorn.