b'Diversifying Weed Controlwith Sustainable SolutionsWith sustainability top-of-mind politically, companies look to sustainable weed control solutions.Melissa ShipmanWEED MANAGEMENT ISjust one aspect of crop production. The idea of sustainable weed control can mean dif-ferent things to different people, but its become clear that too much of a good thing really can be a bad thing, at least in terms of herbicide use.Herbicide resistance, including metabolic herbicide resistance, is lead-ing to some soul searching on how to manage weeds today in agronomic crops, said Martin Williams, a USDA Agricultural Research Service scientist and adjunct professor of crop sciences at the University of Illinois.And while sustainability has yet to be clearly defined in the agricultural space, experts agree that when thinking about weed control, an intentional, multi-layered approach is best. For Liam Vincent, technical marketing manager for BASF, weed control needs to be approached proactively.Sustainable weed control means thinking ahead to ensure that a farmMartin Williams looks into managing weeds in different crop fieldsincluding lima beans.operator has multiple, effective options with which to control weeds today and in the future, he says. in glyphosate-resistant crops, quicklysaid Palmer amaranth is another weed selected for glyphosate-resistant weedwith concerning resistance to nearly nine Rooted in Resistancepopulations, Williams says. different herbicide groups.In the early days of herbicide-resistantThen, continually throwing heavy reli- Over the last several decades, we crops in the mid-1990s, farmers didntance on another active ingredient selectedhave not seen many new herbicide have to give a great deal of thoughtfor additional herbicide resistance.groups or chemistry so were definitely in on how to kill weed plants in soybean,We now have waterhemp populationsa crisis, Jha says.cotton or corn.resistant to seven unique sites of action.Vincent says according to the However, weeds adapt, particularlyThat almost sounds like science fiction,International Herbicide-Resistant Weed to a simplistic approach, which is exactlybut it is a practical case study in the ecol- Database, there is documented weed what was deployed across millions ofogy of waterhemp, Williams says. resistance to 21 of the 31 known herbicide acres, year after year. Over-reliance onPrashant Jha, professor and extensionsites of action and over 160 herbicides.individual tactics, such as glyphosateweed specialist at Iowa State University,Because of this, more growers and 44/ SEEDWORLD.COMJUNE 2022'