Popis: |
Abstract Stakeholders across the state of Nebraska, USA, were surveyed in 2019–2020 to assess problem weeds and weed management practices in agronomic crops. A total of 420 complete responses were obtained across four Nebraska districts (Northeast, Panhandle, Southeast, and West Central). Accumulated across the state, 65.5% of farmed or scouted crop ground in Nebraska was under no‐till production, with the major crops being corn and soybean representing 39.3% and 30.7% of agronomic crop production area, respectively. Palmer amaranth, horseweed, waterhemp, kochia, and giant ragweed were ranked the most problematic weeds. In a 2014–2015 survey, Palmer amaranth was the sixth most problematic weed. The most used preplant herbicides were 2,4‐D, glyphosate, and dicamba in the 2019–2020 survey. Atrazine applied alone or in mixture with acetochlor, bicyclopyrone, clopyralid, mesotrione, or S‐metolachlor were the most applied pre‐emergence (PRE) herbicides in corn, whereas the most applied PRE herbicides in soybean were metribuzin/sulfentrazone, flumioxazin/pyroxasulfone, and chloransulam‐methyl/sulfentrazone. Like the previous survey, glyphosate was the most frequent choice of survey respondents as a post‐emergence (POST) herbicide in glyphosate‐resistant corn and soybean, while 2,4‐D was the most applied POST herbicide in grain sorghum and wheat. Most of the respondents (77%) were aware of the new multiple herbicide‐resistant crops, and 86% listed physical drift and volatility of dicamba/2,4‐D as a primary concern. Twenty‐three percent of survey respondents identified integrated pest management as a primary research and extension priority for profitable agronomic crop production in Nebraska. |