Herbicide resistance has been increasing across Canada for the past four decades, with resistant weeds now found on an estimated 38 million acres of cropland in Western Canada.
According to Hugh Beckie, research scientist with Agriculture and Agri-Food Canada (AAFC), the rising percentage of cropland affected by herbicide resistant weeds is showing no signs of slowing down.
Beckie was part of a team that conducted three rounds of prairie weed surveys in 2001-2003, 2007-2009 and 2014-2017. During each period, the team surveyed one of the three Prairie provinces per season. “Across the Prairies, we quickly found that the more we looked, the more resistance we discovered,” he says.
When Saskatchewan was last evaluated in 2015, the team found that 57 per cent of surveyed cropland had weeds that were resistant to one or more herbicide modes of action.