The impact of waterhemp on soybean yields is very real. The answer can be summarized as follows: there are NO postemergence herbicides that will consistently control these very large weeds in soybean,… Say goodbye to Palmer amaranth. Having explored resistance issues with waterhemp and Palmer amaranth, let's turn our attention to discuss some control options for soybean in fields where resistance has been observed. 3 Due to its genetic variability, wide emergence window, vigorous growth potential, and prolific seed production, waterhemp has become a troublesome weed in marestail) and waterhemp in soybean has remained consistent over the past 10 days. Those populations were resistant to one or more of these products including s-metolachlor, dimethenamid-P, pyroxasulfone, and acetochlor. “The ALS inhibitors (Pursuit, Scepter) are almost completely ineffective against waterhemp in Illinois now,” Hager says. To evaluate the performance of commonly used HG 15 herbicides (pyroxasulfone, S-metolachlor, dimethenamid-P, and acetochlor) on waterhemp in Iowa soybean fields, an analysis on weed control data collected from herbicide evaluation trials was conducted by the Weed Science program at Iowa State University Research Farms from 2015 to 2019. Group 15 herbicides (HG 15) are commonly used for PRE waterhemp control. These results indicate that while all the PRE herbicides selected can provide effective residual control of waterhemp in soybean, pyroxasulfone, sulfentrazone, and metribuzin provided the most consistent early-season control over the 5-year period. The information Use full labeled rates; For postemergence treatments, make timely applications and apply to small pigweed (<4 inches tall). Kyber ™ herbicide is the comprehensive solution to difficult-to-control weeds in soybean fields. CONTROL IN SOYBEAN. Products used in the analysis were applied alone as PRE at the labeled field use rates. Figure 1. “If left untreated, it will compete with soybeans all season long, and can reduce yield by 44%,” said Jeff Stachler, OSU Extension Educator in Auglaize County, and Weed Specialist. 29: 716–729. Weed control options in soybeans. Diligent™ provides the defense you need, plus the flexibility to tank-mix with glyphosate and other residual herbicides. If applied too early, the control of Waterhemp declines. For best control, apply a pre-emergence residual herbicide followed by post-emergence applications as needed throughout the growing season. soybean herbicides in Roundup Ready (RR) or conven-tional soybean systems. A description of herbicide resistance in Illinois waterhemp populations, along with postemergence herbicide options to control waterhemp, follows. Copyright © 2020 Iowa State University of Science and Technology. Two trial sites were established. Waterhemp management in soybean was challenge for several Wisconsin farmers in 2019. Got waterhemp? New herbicide promises control of waterhemp. This strategy will aid in delaying emergence of waterhemp until soybean canopy closure when the crop will be more competitive, thereby reducing selection pressure on POST herbicides and reducing crop-weed competition and protecting against soybean yield losses. Site A was in Seneca County, NY on a field of Odessa silt loam soil where waterhemp had survived various herbicide applications and produced seed in 2018. herbicides, waterhemp, weed control, weed management, weeds. Procedures: Objective 1. Marvel™ herbicide protects soybean yields with superior postemergence control of glyphosate-resistant weeds and broad-spectrum control of other key weeds, including waterhemp, Palmer amaranth/Palmer pigweed, lambsquarters, morningglories and velvetleaf. If this article is to be used in any other manner, permission from Postemergence herbicides for waterhemp control in soybean are essentially limited to two herbicide families, the diphenyl ethers and glyphosate-type products. The main reason we like the combination we listed is the weed control is superior to anything else. Each is a "contact" herbicide, so thorough coverage of the target vegetation is essential for good control. Season-long competition by waterhemp (more than 20 plants per square foot) has been shown to reduce soybean yield by 44%. Ames, IA 50011-2031 “You could use glyphosate, but resistance continues to increase every year. Ideally, a grower would use both a group 14 and a group 2 herbicide if the waterhemp is glyphosate-resistant to slow the selection pressure for multiple-resistant waterhemp. Results from 2015 are described in the Crop News article, Manage waterhemp in soybean with layered residual herbicides. Residual Control of Waterhemp . Protect your soybeans from waterhemp and other weeds with Diligent™ herbicide. June 16, 2016 | Posted in Crop Protection Source: University of Illinois Extension By Aaron Hager, Extension Weed Scientist Waterhemp continues to be one of the most widespread and troublesome broadleaf weed species with which farmers must contend. However, an increased selection pressure from these herbicides used in corn-soybean rotations has resulted in the evolution of HG 15 resistance in waterhemp populations, recently documented in Illinois. Use effective soil applied herbicides at planting. This premix combines three modes of action, each effective individually, to control resistant weeds. Postemergence Soybean Herbicides Diphenyl ethers--acifluorfen (Blazer, Status), lactofen (Cobra), and fomesafen (Reflex, Flexstar). Procedures: Objective 1. The only option is the use of a PPO-inhibiting herbicide such as Flexstar, Cobra, or Ultra Blazer although there are multiple known populations of PPO-resistant Palmer and waterhemp in the state of Kentucky. Having explored resistance issues with waterhemp and Palmer amaranth, let's turn our attention to discuss some control options for soybean in fields where resistance has been observed. Waterhemp management in soybeans was a challenge for several farmers in 2018. Group 14 herbicides are likely the best choice for post-emergence control of glyphosate-resistant waterhemp in Roundup Ready soybeans. Waterhemp resistance to HG 15 has not been confirmed yet in Iowa, however it is important to proactively protect the value of these products for waterhemp control in soybean fields. All rights reserved. Waterhemp Management in Soybeans Waterhemp Biology • Waterhemp gains a competitive advantage over several more aggressive summer annual weeds through the sheer number of plants that can infest an area. Postemergence Herbicides for Soybeans. Group 14 herbicides are likely the best choice for POST-emergence control of glyphosate-resistant waterhemp in Roundup Ready soybeans. The most troublesome multiple-resistant weeds for North American crop production are 2 pigweed species, common waterhemp and Palmer amaranth. (And common ragweed. without further permission if published as written and if credit is given to the author, Integrated Crop Management News,
2020 soybean herbicides for waterhemp