By Dale Fjell
The following is an edited version of an article originally published in conjunction with Kansas Corn. The original article can be found on their website at http://kscorn.com.
There is growing concern from producers this year about volunteer corn and how to control it. While corn is technically a crop and not a weed, volunteer corn can possibly do more harm to your yields than good. Dale Fjell, Kansas Corn Director of Research and Sustainability, and Ignacio Ciampitti, K-State Crop Production and Cropping Systems specialist, have weighed in to give their advice and recommendations.
Farmers may be seeing more volunteer corn this year because of the dry conditions. Normally, the volunteer corn would sprout early, giving farmers a chance to eradicate it. In drier areas this year, the volunteer corn may be emerging at the same time as this year’s planted corn, Fjell said.
According to Fjell, the widespread adoption of Roundup Ready corn can make management of volunteer corn in corn fields a little complicated. There are really only a few options, other than cultivation, available to control volunteer corn once this year’s corn has emerged.
“Volunteer corn is highly competitive with both corn and soybeans,” Fjell says. “Timely management is critical to protect crop yields infested with this plant.”
He urges farmers to take care of the volunteer corn as soon as possible to minimize potential impact on water use (more precisely in dryland environments) and to increase the probability of achieving full control and minimizing the potential impact on corn yields.
Ciampitti cites some research studies done on the effects of volunteer corn.
- In 2007, researchers at South Dakota State University indicated that volunteer corn is much less competitive in corn than soybean. The South Dakota study (Alms et al. 2007) evaluated the full season effect of a range of volunteer corn densities (800-14,000 plants/acre) on both corn and soybean and reported yield losses that ranged from 0% to 13% in corn and 0% to 54% in soybean.
- A 2007 University of Minnesota (U of M) study reported yield loss potential in corn that was very similar to the South Dakota study.
- Iowa State reported one volunteer corn plant per 10 ft. of row reduced corn yield 1.3%.
The yield impact on corn is likely due to volunteer corn’s reduced demand for resources and the competitive vigor of the planted F1 hybrid, Ciampitti says. Volunteer corn has a lower yield potential than the planted F1 hybrid resulting from delayed emergence. In the U of M study, volunteer corn plants lagged from one to six leaf stages behind the crop and few plants produced an ear by harvest.
Ciampitti offers this advice to growers facing a volunteer corn problem, “If volunteer corn populations are high and conditions remain dry, inter-row cultivation is the most cost-effective option in corn unless the herbicide-resistance traits of volunteer corn and the planted corn differ; then herbicide control is possible.”