Spray or Seed First? Plus, Why you Shouldn't Grow De-Registered Varieties


Canola Seedlings Fert BurnIn a tight seeding window, is it better to seed first and spray later, or is a pre-seed burn-off a must? That’s the question we asked Kristen Phillips, agronomy specialist for Manitoba with the Canola Council of Canada. She says that 24 hours is all you need after a glyphosate application before heading in to seed that field. Going in prior to that is still safe for the canola, but it’s less likely to result in as good a kill of weeds as you’re targeting. If you’re going to take the time and money to spray, give the herbicide a chance to do its job completely, or face disappointment later.

Alternatively, if you simply couldn’t spray prior to seeding, all is not lost — Phillips says waiting two days after seeding is safe and also allows weeds disturbed at seeding to re-establish growth so that they can take up the herbicide. Canola takes about 5 days under ideal conditions to germinate, so keep that in mind.

Phillips also notes that if you’ve got very large weeds that you know you won’t get 100% control of pre-seed, it’s still better to hit them first, even at a 60% control rate, than wait. “The bigger they are the harder they are to kill and the more nutrients and water they’ve used,” she says. Earlier control is always going to be worth it in this circumstance, so prioritize a spray over seeding.

Stop Seeding De-Registered Varieties!

Last week the Canola Council of Canada reminded farmers not to grow any de-registered varieties. Farmers delivering canola will have to declare that all shipments DO NOT contain any of the varieties on this list.

“De-registered varieties can be detected at very low levels and will result in rejected export shipments and increased monitoring of Canadian canola,” Phillips says.

Phillips explains that there are market factors at play here — as few as nine (9) seeds in a super-B load could possibly close international markets to Canadian canola. Growing these varieties just isn’t worth the risk.

What do you do if you have left over seed of these varieties or a bin contaminated with the seed? When it comes to managing deregistered varieties contact the seed company that provided the variety, the grain company or your local Canola Council agronomist and they will help you figure out a solution.

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