North Carolina grower Kip Roberson makes short work of glyphosate-resistant weeds in soybeans. He accomplishes this by applying a postemergence treatment of ET herbicide tankmixed with glyphosate.
“ET is great herbicide for stopping weeds at the small stage as well as when they get a little bigger,” says Roberson, who lives in Robersonville. “I applied the tankmix over the top for glyphosate-resistant pigweed when they were about six inches tall. It totally destroyed the glyphosate-resistant pigweed; it just burned them right up! It also provided good control of other weeds, including morningglory and cocklebur.”
Fast Control Noted
ET burns down glyphosate-resistant weeds and other weeds quickly. Glyphosate alone takes between 14 to 21 days to control weed species. Adding ET herbicide to glyphosate reduces the control interval from 21 to as little as three days.
“I saw faster control with the ET plus glyphosate tankmix, which took about eight days to control the weeds,” Roberson says. “That faster control is important to me because I don’t have to wait long to see if I have control.”
ET herbicide, a Nichino America product, offers soybean growers an alternate mode of action for resistance management. ET is effective against ALS-, triazine- and glyphosate-resistant species. ET also allows for application flexibility, is rainfast within one hour, has low volatility and is tankmix compatible with a multitude of herbicides. It is also effective in cool and wet conditions and is very economical.
“ET is definitely very cost-effective; it’s an inexpensive product that works so well for us,” Roberson adds. “We have used ET for almost eight years now in our cotton defoliation program. This was the first year that we used it as an herbicide in our soybeans, and we really like the results.”
ET is a contact herbicide and thorough coverage is essential for best results. Nichino America recommends that ET be applied with a NIS-type adjuvant in a minimum of 15 GPA water volume.
ET should be applied to weeds that are four inches or smaller, as pictured above, for optimal results.
Short term speckling
Postemergent applications of ET on soybeans will typically cause temporary herbicidal speckling; however, this speckling will not occur on new growth.
Roberson noticed his ET plus glyphosate application speckled his treated beans last year. “But give it three to four days, and the soybeans will come right out it,” he says. “After two weeks, you won’t even know that you sprayed it. We did not lose any yield. As a matter of fact, the ET-treated beans were probably some of my better yielders.”
This North Carolina grower normally starts his soybean weed control program with a burndown application in mid-April with glyphosate, 2,4-D and Valor. “After I plant my soybeans, I apply Prefix,” Roberson says.
“Once the soybeans emerge, I will get in an application of Roundup. Then about 14 to 15 days later when another flush of weeds comes in, I will go back with the ET plus Roundup tankmix, which keeps my soybean fields real clean.”
Roberson always plants a portion of his soybeans in maturity groups VI and VII. He farms no-till and plants on 7 1/2-inch centers. He starts planting full season soybeans the last week of April or first week of May.
“If I am planting behind wheat, I will probably begin planting in the first week of June if moisture permits,” he says. “With my crop inputs, my dryland soybeans normally average around 40 to 45 bushels per acre. This past season was very dry, so we averaged about 30 bushels per acre.”
ET is a very versatile, effective product in Roberson’s operation. He has used it for many years as a cotton defoliant, but now it provides him a new tool for postemergence control of glyphosate-resistant weeds in his soybean crop.
Ninchino America contributed information for this article.