Corn and soybean farmers test-drove several new herbicides over the rugged proving ground of the 2013 growing season. The new active ingredient pyroxasulfone appears in three new products: Zidua, Anthem and Fierce.
New options for the weed control tool kit
“Pyroxasulfone is the first active in a new class of Group 15 herbicides, the same group as s-metolachlor (Dual products) and acetochlor (Harness, Degree, Warrant),” says George Watters of Noblesville, Ind., regional agronomist for WinField in Indiana.
“The new products are exciting because they combine the best attributes of s-metolachlor – long-lasting grass control – and acetochlor – activity against small-seeded broadleaf weeds – but with longer residual control and lower use rates,” Watters says.
In 2013, Tegtmeier applied a spring burndown of glyphosate and 2,4-D followed by a preemergence application of Instigate and either Cinch ATZ or Access ATZ.
“The Instigate helped provide season-long control where other products might be fading out,” Tegtmeier says, “and held back weeds to improve yields, especially where stands were not as strong as other areas.”
Dicamba- and 2,4-D-tolerant systems delayed
In May, the USDA’s Animal and Plant Health Inspection Service (APHIS) announced that it would create Environmental Impact statements (EIS) for Monsanto’s new dicamba-tolerant Roundup Ready 2 Xtend soybeans and Dow AgroSciences’ new 2,4-D-tolerant Enlist Weed Control System.
Although it's not known exactly how long the EISes will require, Monsanto is working toward a 2015 launch for soybeans, pending regulatory approvals.
Dow AgroSciences expects to launch Enlist corn and soybeans in 2015, with cotton to follow, pending label approvals.
1. Anthem by FMC
<p>David Gummert, agronomy center manager for Van Diest Farm Supply in Gilmore City, Iowa, recommends FMC’s Anthem, a combination of pyroxasulfone and fluthiacet-methyl, the active ingredient in FMC’s Cadet, to customers faced with herbicide-resistant waterhemp and severe sunflower and velvetleaf infestations.</p>
<p>No-till corn and soybean grower Paul Sefcik of Ottosen, Iowa, says he knew he had to do something differently when waterhemp began to survive multiple glyphosate applications. “I had planted Roundup Ready corn and soybeans for a long time,” Sefcik says. “The Roundup used to work okay, but after a while the waterhemp was still coming up, even after a third glyphosate application.”</p>
<p>Van Diest’s Gummert says wet weather prevented a spring burndown application on Sefcik’s fields, leading to a planned postemergence treatment at the V4 – V5 stage with 8 ounces per acre of Anthem and 36 ounces per acre of glyphosate. Says Sefcik, “Anthem works really well; I had a nice clean field with no setbacks.”</p>
<p><a href="http://www.fmccrop.com/grower/products/herbicides/anthem.aspx" target="_blank">Get more information about Anthem.</a></p>
2. Fierce by Valent
<p>Fierce combines pyroxasulfone with flumioxazin, the active ingredient in Valent’s Valor. Farmer Lance Panzier of Waltonville, Ill., tried Fierce on his 2013 soybean crop because herbicide-resistant waterhemp has become a major problem for him. “We have to be proactive to keep it down,” he says.</p>
<p>Panzier sprayed Dual with glyphosate as a burndown and applied 3 ounces per acre of Fierce immediately after planting soybeans. He applied Roundup and Flexar or Roundup and Liberty, depending on the soybean variety, 21-28 days after planting.</p>
<p>“Fierce was awesome on the waterhemp,” Panzier says. “It held down the waterhemp for the entire season. A lot of growers in the area who did not use Fierce or another product with long residual had to go back in with Cobra for the escaped weeds.”</p>
<p><a href="http://www.valent.com/agriculture/products/fierce/" target="_blank">Get more information about Fierce.</a></p>
3. Instigate by DuPont
<p>“DuPont Crop Protection launched Instigate (rimsulfuron + mesotrione) in the eastern Corn Belt in 2013 and plans to increase distribution across the entire corn and soybean growing region in 2014,” says Jeff Carpenter, DuPont corn portfolio product manager.</p>
<p>Strip tiller Randy Tegtmeier of West Salem, Ohio, applied Instigate to battle marestail on his 2013 corn crop because it can be applied beginning 14 days preplant, preemergence or early post until the V2 stage. “I like to front-load my herbicide program and prefer not to apply anything after 6-8 leaves,” he says.</p>
<p><a href="http://www.dupont.com/products-and-services/crop-protection/corn-protect... target="_blank">Get more information about Instigate.</a></p>
4. Zidua by BASF
<p>Dumas, Ark., grower Nelson Crow applied Zidua, a stand-alone formulation of pyroxasulfone, in a soybean field planted to rice in 2012. “Zidua is death on grasses,” Crow says. It can be applied with glyphosate as a burndown or over the top after planting; it works just as well either way.”</p>
<p> Crow applied 1 ounce per acre of Zidua in fields that will be in rice next year and the full rate of 2 ounces per acre on the rest of his fields.</p>
<p>“This was the first year it was fun combining because I didn’t have sunflowers and velvetleaf everywhere,” says Glenn Davis of Gilmore City, Iowa. He grows corn and alfalfa for his 300-head dairy herd. “Sunflowers and velvetleaf got worse and worse as we spread manure containing weed seeds back on the fields year after year,” he says. “We had tried a bunch of chemicals at higher rates and still had to come back in September and October with 2,4-D to keep the weed pressure down.”</p>
<p>Van Diest Farm Supply sprayed 8 ounces per acre of Anthem and 28 ounces per acre of glyphosate on Davis’s corn June 16. </p>
<p><a href="http://www.agproducts.basf.us/products/zidua-herbicide.html" target="_blank">Get more information about Zidua.</a></p>