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Herbicide resistance a global food threat [Winnipeg Free Press (Canada)](Winnipeg Free Press (Canada) Via Acquire Media NewsEdge) For decades, the experts have treated the growing problem of herbicide-resistant weeds as something solvable by the next new chemical or biological breakthrough. Now, more are stepping back and acknowledging it as a symptom of a much bigger issue in agriculture. In fact, one of the world's leading experts in managing herbicide resistance goes so far as to call it a sickness that threatens global food security. Stephen Powles, who heads up the Australian Herbicide Resistance Initiative at the University of Western Australia, has even given it a name -- HOS (herbicide-only syndrome). He was among several speakers at a summit recently held in Washington, D.C., and broadcast live over the Internet, who made a compelling argument something has to change -- and fast. Despite decades of research to raise awareness and promote better management practices, the list of resistant weeds continues to grow and their grip on farmers' fields continues to spread. With weeds that are now out of control in some southern U.S. states, farmers are returning to tillage -- which most agree has ominous implications for soil health and future productivity. Last week a British weed specialist brought a chilling message to Prairie farmers about the difficulty and cost of controlling herbicide-resistant blackgrass in Europe. Farmers there are resorting to older, more residual products that are tilled into the soil, a practice now being promoted here. In Manitoba, kochia, wild oats, and green foxtail have become resistant to one or more herbicides. Across Western Canada, a 2012 survey estimated weeds resistant to one or more herbicides had infested 7.7 million hectares, or about 20 per cent of the arable land. Powles said the rising incidence of weeds resistant to multiple modes of action is evidence farming's dependence on chemistry alone is unsustainable. It is a threat to global food security as it mainly affects farmers in the world's top exporting countries, Powles noted. Farmers in lesser developed countries still retain a higher degree of diversity and are less likely to use herbicides. The event sponsored by the Weed Science Society of America (WSSA) and hosted by the National Research Council turned to some unlikely resources for advice -- sociologists. "Fundamentally, at its core, it is a problem of human behaviour -- it's the choices you and I have been making," said David Shaw, chairman of the WSSA Herbicide Resistance Education Committee. "Do you know what the definition of insanity is? It's continuing to do what we have been doing, expecting different results." As the speakers at this event pointed out, the discussion over herbicide-resistance management needs to move beyond raising awareness and telling farmers what to do about it. Farmers are aware. The latest poll by BASF of farmers' attitudes found 94 per cent of Manitoba farmers are worried about herbicide resistance, and nearly 60 per cent think they already have it. The things they need to do to avoid it are well-documented. Yet many are waiting until they have the problem before taking action -- and then it's too late. Once weeds have evolved resistance, there is no going back. In sociological terms, HOS is considered a "wicked problem," which means it has multiple and complex causes that defy simple solutions, said Raymond Jussaume, head of the sociology department at Michigan State University. Addressing this will require all players in the system to move as a community towards a more holistic approach, he said. Regulation is one of the options on the table. But far more effective is a community based approach in which farmers help determine the goals and monitor progress, speakers said. Herbicide manufacturers and distributors are already well aware of the threat of herbicides becoming redundant, which ultimately means no market for their product. Their message to rotate herbicides to prevent resistance is well taken. But to keep them in the toolbox, it will also mean using them less often. That message has been slow to sink in. Laura Rance is editor of the Manitoba Co-operator. She can be reached at 204-792-4382 or by email: [email protected] (c) 2014 F.P. Canadian Newspapers Limited Partnership |