The Sound of Volunteer Corn
Remember the song How do you solve a problem like Maria from the 1965 movie The Sound of Music?
Well, if Rogers and Hammerstein were writing about growing corn, they’d write this song: How do you solve a problem like volunteer corn?
Volunteer corn is an increasing weed problem significantly impacting yields. “It is a competitive plant,” says Carroll Moseley, herbicide brand manager for Syngenta Crop Protection.
South Dakota State University research demonstrated corn yield loss approaches 13% when volunteer corn density is extremely high, about 15,000 plants per acre.
In 2010, volunteer concentrations went even higher. Several situations occurred where farmers replanted due to high volunteer corn levels, says Craig Abell, Syngenta technical support representative. In some cases, volunteer corn populations tallied over 100,000 plants per acre—around three times higher than normal planting rates.
The situation was set up by the delayed 2009 harvest, says Abell. Corn-on-corn had high amounts of volunteer corn that followed the 2009 harvest, which continued into winter in some areas.
What to do?
Well, crop rotation still works. In soybeans, for example, a number of fop’ and ‘dim’ herbicides can be sprayed postemergence to clean up volunteer corn.
It is tougher for volunteer corn in corn. A postemergence corn herbicide that doesn’t coincide with the corn’s herbicide-tolerant trait will kill all corn,
One option is to plant a glufosinate-tolerant crop in the previous year’s glyphosate-tolerant crop. (Or vice versa.)
Multiple-herbicide trait stacks complicate volunteer corn control. For example, stacks that combine several weed control systems halt this option, says Jeff Springsteen, Bayer CropScience marketing manager for selective corn herbicides.
You could scour tree claims and weed patches behind your shop for cultivators. Cultivation is an option, though not a realistic one. Besides costing time and labor, cultivation also dashes no-till strategies.
“One of the bigger things is to think about is the way to minimize volunteer corn in the field,” says Bruce Battles, agronomy marketing manager for Syngenta Seeds.
“A lot of this is related with hybrid selection,” he adds. “It’s important to important to select hybrids with good stalk quality that are not going to fall down and lose ears.”
Fungicides can also play a role, he adds. That’s because plants treated with a strobilurin fungicide typically stay greener longer and have better plant health. This results in better standing corn and less harvest loss, Battles says.