How Do I Control Volunteer Corn?
Jan 31, 2013
Question: I’m having problems with volunteer corn in my corn crop. How do I control it?
Answer: I’m not sure of your specific agronomic practices, seed traits etc., so I’m going to offer a couple of thoughts for your consideration. If the previous crop you grew was conventional corn, you have more options. The obvious one is to rotate to soybeans this year. Another option (depending on what seed you purchased) is to plant Roundup-tolerant corn and use Roundup herbicide in a postemergence application. If you grew glyphosate-resistant corn last year, plant LibertyLink corn and apply a postemergence application of Liberty. It gets tricky, though, when you grow continuous corn with hybrids that contain both Roundup Ready and LibertyLink traits. Those traits stacked together can be good in a corn-soybean rotation, but in a corn-on-corn rotation you really need to separate those traits, so you can use one or the other to clean up weeds. Another option that I acknowledge is probably next to impossible for someone in the northern corn-growing areas is to plant corn later than normal after controlling the volunteer corn. Basically, you want to get out and get your seedbed ready early. Level up that ground and then wait for the right soil temperature. At 50°F corn germinates, and at 55°F it gets really active. You want to let that volunteer corn sprout up to about two collars and then spray Fusilade or Poast or work the ground again with secondary tillage, such as with a field cultivator. One caution, be aware that today’s vertical-till harrows are not very good at removing volunteer corn and can make it worse. It can shatter those corn ears and cause reseeding. I don’t know what your harvest was like last year, but if you had a 20-bu. or 30-bu. harvest loss when you went through the field last fall, you potentially will have a mess this spring. Even if 90% of it was killed by frost last fall, that other 10% will have to be managed. Get on top of it as soon as you can.