Simon North
Cargill AG expert
Many prairie growers are now tank mixing herbicides and making a pre-seed pass in their cereal rotation. Here are four reasons to do the same in canola.
More growers are starting to tank mix two herbicide modes of action for a pre-seed burndown in their cereal crop. I want to encourage you to do the same in your canola crop. While the herbicides cost a little more than the ones we use in cereals, it will pay off with a healthier crop this year while lowering your risk of herbicide-resistant weeds in the future.
This is the year to add a tank-mix partner to your pre-seed glyphosate burndown. Here’s why.
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We’re seeing an increase in Group 2 resistant cleavers and kochia
Weed researchers are reporting increases in herbicide-resistant weed populations across Western Canada – particularly Group 2 resistant weeds. Cleavers and kochia can be very competitive early on, stealing resources from your germinating crop and taking away its yield potential.
Control these weeds early to create the clean, weed-free seedbed you need for healthy stand establishment. It will make a big difference on the yield.
Thinner plant stands are more susceptible to weed pressure
Seed costs are on the rise, and I’ve seen many growers reducing their seeding rates to stretch each bag of canola further. Crop competition is normally a powerful weed management tool. When stands are thin, you’re going to see more weed pressure. Use herbicides proactively to reduce competition.
Volunteer issues escalate in tight rotations
For many years, canola has been the most profitable crop on the Prairies. People are growing wheat-canola-wheat rotations, and as a result, we’re seeing a lot more canola volunteers from different trait systems. The grain that falls out the back of the combine can stay dormant in the soil for two to three years. I’ve even seen volunteer canola growing in a freshly-tilled field that had been seeded to grass for seven years!
Volunteer canola is very competitive early in the season, and depending on the system you use in any given year, your in-crop control options can be limited. Take advantage of that pre-seed pass to clean it up – especially if you’re growing an identity preserved canola variety in 2017.
Weeds, insects and disease get a head start
The winter annuals, weeds and the canola volunteers that emerge early in the season don’t just mine the soil of water and nutrients; they can also harbour disease and insects. These pests will get a two-to-three week head start on your crop – particularly in minimum tillage systems. That means you’ll be seeding into hostile territory.
It’s a lot more efficient to control big weeds and volunteers at pre-seed, when you can apply more active ingredient, than at your in-crop application, where application rates are limited.
Add a Group 6 or a Group 14 to the tank with glyphosate
Here are my top suggestions for your pre-seed burndown:
- Glyphosate + a Group 6 like Pardner®
- Glyphosate + a Group 13 like Command®, which also provides residual cleaver control
- Glyphosate + a Group 14 like Conquer™, which also contains bromoxynil (a Group 6 and the active ingredient in Pardner)
Both these options are safe ahead of canola, and they control wild buckwheat, narrow-leaved hawk’s-beard, cleavers and kochia.
The ROI of tank mixing
When you control weeds early on, you can protect yield early on. Canola is not competitive during its early growth stages, so it’s critical to have a weed-free seedbed.
A cleaner seedbed also puts you in a good position for your in-crop application. If we get a lot of rain in June and you can’t get into the field (like we saw in 2016), you avoid the risk of missing the in-crop window and losing control of the weed population. You may also be able to cut back your in-crop application and make one pass instead of two.
Over 99 per cent of the canola grown in Western Canada is herbicide-tolerant canola, and depending on the system you choose, you’re spraying either glyphosate or Liberty® every time. There is no new herbicide-tolerance innovation coming down the pipeline anytime soon. For the future of canola production, we must protect the long-term viability of our chemicals. Tank mixing at pre-seed is one of the best ways to keep your glyphosate or Liberty effective.
If you want to get early-season control of a problem weed or canola volunteers, talk to your Cargill representative. We can recommend a glyphosate tank-mix solution that will maximize your ROI, prepare a clean seedbed and help keep your herbicides effective for the future.
Always read and follow label directions. Pardner and Liberty are registered trademarks of Bayer. Conquer is a trademark of Nufarm Agriculture Inc. Command is a registered trademark of FMC corporation.
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