Wild oats have successfully annoyed farmers across western Canada for decades. They’re a nuisance that just won’t go away. To make matters worse, trusted Group 1 and 2 in-crop herbicides are becoming less effective as herbicide-resistant populations continue to develop and spread. The impact of resistant wild oats is significant. Wild oats are costing prairie farmers an estimated $500 million annually through yield and crop quality losses1.

The best way to manage wild oats is through a multi-year and multi-pronged approach that reduces the seedbank year after year. While most wild oat seeds germinate within two years, seeds can survive in the soil for much longer. Seeds can germinate when temperatures range from 5-30° C, and wild oat flushes are common throughout the spring, taking valuable moisture and nutrients away from crops.

When managing wild oats, it’s important to consider best practices for delaying herbicide resistance.

  1. Change up your farm practices. Do something different every year to throw weeds off their game. Alter herbicide application timings or include an application timing you haven’t done before.
  2. Rotate crops. Seed different crops and change growing habits and competition levels in your fields.
  3. Rotate herbicide mixtures. Use different modes of action and products with multiple modes of action. Rotate tank-mixes and change application timings.
  4. Scout for survivors. After spraying get out in the field and see if you can find patches or individuals that were not controlled – testing for resistance to most modes of action is available in Canada. Finding and managing those patches/fields early can save money and time in the long run.
  5. Keep records. Knowledge is power. Keep track of what you’ve done in the past and keep it easily accessible for planning next year.


Different application timing, different modes of action

Fierce® EZ is a great tool to help manage and suppress flushing wild oats. This soil active herbicide offers extended residual control on a long list of broadleaf and grass weeds. It features two active ingredients (Group 14, 15) and delivers up to eight weeks of residual activity on a wide-spectrum of tough-to-kill broadleaf weeds including herbicide-resistant kochia and cleavers.

Apply Fierce in the fall, after harvest and before freeze-up, ahead of peas, lentils, wheat (spring, winter) and soybeans with no re-cropping restrictions the following spring. If you miss a fall application, apply early in the spring ahead of peas, wheat and soybeans.

Below is an image of Fierce EZ working in the field on wild oats. Jason Casselman and Nufarm Territory Manager, Talbot Rycroft took this photo where the farmer left a checkstrip. With heavy populations, the herbicide did an excellent job of suppressing wild oats in the pea crop.

If you’ve struggled to get a handle on wild oats and challenging broadleaf weeds, it’s time to change things up! Talk to your local retailer or Nufarm Territory Manager about applying Fierce in the fall or early spring. Leave a checkstrip and see what the product can do for your fields.


  1. Manitoba Agriculture, Wild Oats. https://www.gov.mb.ca/agriculture/crops/weeds/wild-oats.html#:~:text=Wild%20oats%20is%20the%20most,and%20lowers%20grade%20and%20quality.