Bismarck Farm and Ranch Guide, ND
03-18-07
Volunteer corn poses significant challenge for producers
By Tim Hoskins, For Farm & Ranch Guide
While traditional weeds will continue to be the main problem most Iowa farmers will face, certain areas will have significant volunteer corn issues in 2007.
“There is an increased likelihood for more volunteer corn in 2007,” says Mike Owen, Iowa State University Extension weed specialist.
The reason is due to environmental conditions, such as wind damage in 2006. Volunteer corn will likely be present in soybeans and corn fields.
He says volunteer corn has always been a tough weed to control but use of biotech hybrids might make it even tougher.
Field history should be on the top of a farmer's mind when dealing with volunteer corn.
In soybean fields, which are most likely glyphosate resistant, Owen says the volunteer corn could be glyphosate resistant as well if resistant corn was grown in the same field the previous year.
Another reason volunteer corn may be Roundup Ready is due to pollen drift from neighboring glyphosate-resistant corn fields.
“Pollen does not understand field boundaries. It goes where it wants to go,” Owen notes.
He says if the volunteer corn is Roundup Ready, it is best to mix a post-emergence grass herbicide with the Roundup application. However, if it isn't glyphosate-resistant volunteer corn, a glyphosate application should take care of it.
If the glyphosate application does not take care of it, a post-emergence grass herbicide application might be needed, which would require another field pass.
Controlling volunteer corn in a planted corn field might require more management.
Owen says volunteer corn has always been hard to control in corn fields.
Field history could be another factor to solve the problem of volunteer corn in corn.
He says one solution for Roundup Ready volunteer corn, especially in corn fields, is to plant Liberty Link hybrids.
Using a Liberty Link system also would help control any selection pressure for glyphosate-resistant weeds in a field, Owen says.
However, he says farmers need to note the field history and what was grown in fields next to them the past year if they plan to switch to a Liberty Link hybrid to control Roundup Ready volunteer corn.
While using the Liberty Link system could effectively control Roundup Ready volunteer corn, it might not be effective in controlling volunteer corn from Hereclux/
Roundup Ready hybrids.
That is because the Liberty Link gene is a marker for the Herelcux trait. Therefore, switching to a Liberty Link corn hybrid might not solve the problem.
He says this drives home the point the glyphosate-resistant system is not an easy system.
“People think this system is simple. It is not,” Owen says.