Top 5 Most Troublesome Broadleaf Weeds in Western Canada

If asked to name the most troublesome broadleaf weeds on your farm, you could likely rattle off a few that you battle every year. If you had to think about your top five, would they be the same five that others in Western Canada are battling? What about in your province, or soil zone?

We were curious, too. We looked into an independent study* conducted by AgData in 2014 that surveyed farmers in Western Canada to determine the broadleaf weeds that plague growers more than any others.

The Western Canada top five:

  1. Volunteer canola
  2. Kochia
  3. Wild buckwheat
  4. Cleavers
  5. Stinkweed

Most of these broadleaf weeds are all too familiar to Western Canadian growers, but some more recently than others. In a Prairie Weed Survey from 2001-03, volunteer canola was not even in the top 10. A substantial increase in canola acres since then has likely played the largest part in its prevalence as a weed, says Andrew Clements, agronomist with Premium Ag in Okotoks, Alta.

How does that differ by province? In Alberta and Saskatchewan, the same five weeds make up the top five. Volunteer canola takes the top rank in both Alberta and Saskatchewan but loses out to wild buckwheat in Manitoba. Manitoba is the only Prairie Province to have wild mustard as a top five broadleaf weed and not have stinkweed in their top five.

Broadleaf Weed Map by Provinces

Another way we often look at weed pressures is the soil zones that they thrive in. See the map below for where the brown, dark brown and black soil zones can be found in Western Canada. Volunteer canola once again dominates the map as the No. 1 broadleaf weed in the dark brown and black soil zones. In both brown and dark brown soil zones, flixweed appears as one of the top five concerns. The black soil zone shows as the only zone with hemp nettle in the top five. Also of interest is that the brown soil zone does not include volunteer canola in the top five – it comes in at No. 6.

Broadleaf Weed Map by Soilzone

For each of the weeds mentioned above – eight in total – Stellar™ herbicide has a labelled control, including Group 2 and 9 resistant kochia, Group 2 resistant cleavers and hemp nettle. Growers and agronomists including Andrew Clements are no strangers to the strong annual broadleaf weed control provided by Stellar.

“I use a lot of Stellar; it’s a really effective chemical in oats and cereals,” Clements says. “Stellar has a good activity on a lot of the difficult weeds we’re after like narrow-leaved hawk’s-beard and wild buckwheat.”

*Source: 2014 AgData BPI+ Cereal Spring Herbicide Market
Western Canada Study