The number of herbicide-resistant weed cases is growing while the list of modes of action available for controlling these weeds is not, so farmers in Western Canada have shifted back to soil-applied herbicides, including some old chemistries, like Edge and Avadex.
“We’re going full-circle here. These are older chemistries, but they’re coming back in and growers are seeing the value in them,” notes Mike Grenier of Gowan Canada, in the interview below.
Gowan recently acquired Edge and Treflan from Dow, adding them to a portfolio that already included Avadex and Fortress.
“These soil applied products have unique modes of action and now that they can be surface-applied in no-till situations, we’re seeing a lot of growers bringing them back into their programs as a base layer in a sequential treatment,” explains Grenier.
Group 1 and 2 resistance in wild oats is driving increased use of Group 8 Avadex and Fortress, he says: “Fall treatment as a surface application for no-till, we’re seeing a really big increase in that use pattern.”
Group 3 Edge is also making a comeback with glyphosate-resistant kochia, as it offers better broadleaf control.
But it’s not all old brands — there are also some new soil-applied products, including group 14s and 15s, that growers can use to mix up their weed control chemistries.
Grenier notes they’re encouraging growers to not wait until they have a resistance problem before using a soil-applied herbicide.
“We certainly are trying to help guys that have weed resistance issues in their field today, but we’re trying to have other growers who are a little bit further away understand that being proactive is still the best approach.”
Grenier joined Kelvin Heppner at CropConnect to talk about the comeback of soil-applied residual herbicides and their fit in Western Canada: