What is in this article?:
• Everyone probably should not be using the same program.
When you look at the yield data, there’s not a statistical difference in yield between the recommend postemergence treatments.
POST-HARVEST CONTROL is an important component of controlling troublesome corn weeds such as glyphosate-resistant Palmer amaranth pigweed and tropical spiderwort.
Georgia corn producers have several good options for herbicide programs, but Extension Weed Scientist Eric Prostko says that if he was king for a day, he’d require one thing.
“If you had to do at least one thing that I say, I would tell you to spray a quart of atrazine at planting, for a couple of reasons,” says Prostko.
“If we use a quart at planting, that would allow us to use 1.5 over-the-top, and that gives us the maximum legal amount of atrazine we can use in corn.”
Another reason he cites is time savings. “One of your most precious commodities is time, and the ability to get into the field on a timely basis. If we use a quart of atrazine at planting and it gets activated, it’s likely we’ll get very good control of pigweed. It buys you time to make a postemergence application. You might need to tend to other crops, or you might have bad weather.
“We all know he key to postemergence applications is timeliness,” he says.
For most corn producers in Georgia, it boils down to one or two products, says Prostko, including atrazine plus glyphosate or Roundup Ready, Liberty Link, Steadfast Q, Laudis or Capreno or Halex 6T, which is glyphosate, Callisto and Dual.
“All of these are very good products that do a very good job on the weed species we have.
With all of our recommended programs, we see very good control of the targeted weed species, especially of pigweed. I’m always asked which program works the best, and which one growers should be using.
“Everyone probably should not be using the same program. When you look at the yield data, there’s not a statistical difference in yield between the recommend postemergence treatments.
“One program may be better than another in certain situations, but it generally doesn’t translate into yield. All these programs are very good, as long as we’re getting them out in a timely fashion,” he says.
Many corn producers become concerned, says Prostko, when their plants turn yellow from early herbicide applications.