Choosing how to harvest canola isn’t always straightforward — even when you’re growing a hybrid with pod shatter resistance. While this trait is an important first requirement for straight-cutting, field and environmental conditions ultimately determine whether it’s the right choice in a given year. Knowing what to look for as the crop approaches maturity can help minimize seed loss and support a smooth, efficient harvest.
Planning Your Straight-Cut Approach
Growing a canola hybrid with pod shatter resistance doesn’t automatically mean you should straight cut. That trait simply opens the door to the option. The ideal straight-cut crop has uniform maturity, a well-knit stand, and minimal weed pressure. Throughout the season, biotic and abiotic stressors — including insects and weather events — can weaken pod integrity, so walking fields and checking whether pods are holding or shelling prematurely is essential.
As you move closer to harvest, the risk of early frost increases. There’s no single rule for how to respond: a hard frost can cause pods to split and drop, which may influence both yield and your final harvest method.
BrettYoung’s Agronomic & Regulatory Services Manager, Justine Cornelsen, emphasizes monitoring seed colour change.
“Checking seed colour change every couple of days provides a great opportunity to also assess pod integrity,” she explained. “Then you can determine if diseases like blackleg are causing your pods to shell out. Hybrids with pod shatter reduction traits will act differently under varying environmental conditions, so assessments on how well they perform will help make future hybrid selection decisions easier.”
Deciding to Straight Cut
The decision to straight cut can be difficult when green weed plant material is present. Cornelsen said weedy, uneven, thin or even lodged crops can change a grower’s mind between swathing or straight-combining the crop. A thin, short crop, if swathed, doesn’t make a nice windrow to pick up and could be subject to blowing if not anchored well. If left to stand, though, a thin crop may not feed well into the header when straight-combined.
“It basically comes down to a personal preference on how best to harvest the crop to best minimize seed losses,” said Cornelsen.
Using a harvest aid may be warranted to help speed up dry down of a swath, to even out the maturity of the crop or to combat green weed growth.
Pre-Harvest Aids
With dry, warm days during harvest, your crop and its weeds have time to dry down naturally. But if the forecast doesn’t look cooperative, if you end up trying to beat frost or if you’re on a time crunch, a pre-harvest spray may be necessary to help prepare your canola for straight-combining. The purpose of using a pre-harvest application is for weed control and crop desiccation.
The Canola Council of Canada lists three main options for pre-harvest aids:
- Desiccation (Diquat): Fast drydown
- Pre-harvest glyphosate: Perennial weed control
- Heat LQ (Saflufenacil): Dry down and annual weed control
For most regions of the Prairies, there’s been drier late-season weather this year, making for little benefit when using a pre-harvest application. Cornelsen mentioned that for areas with canola crops with lots of plant biomass, a pre-harvest application could help with harvest timing.
“These tall canola crops with thicker green stalks benefit from a pre-harvest spray to help dry down the stalk to allow for a smoother straight-combining experience,” she said.
Cornelsen reminds growers none of the pre-harvest aids help to quicken plant physiological maturity.
Pod DefendR® Trait
Our Pod DefendR® trait is defined as a dependable level of shatter tolerance, well suited to straight cut or delayed swathing harvest systems. BY 6217TF and BY 6211TF both contain the Pod DefendR technology and we’ll have a new LibertyLink® hybrid coming for the 2024 growing season with Pod DefendR too.
With the introduction of the Canola Council of Canada’s canola shatter rating scale, all hybrids at BrettYoung are assessed for their shatter tolerance.
Products must be rated as a 7 or higher on the scale to receive the Pod DefendR designation.
So, whether swathing or straight-combining, timing is everything for canola.
FAQ
Does having a canola hybrid with pod shatter resistance mean you must straight cut your crop?
No, growing a canola hybrid with pod shatter resistance does not mean you are required to straight cut. There are other considerations like crop uniformity, weed growth and pod integrity that also play a role in your harvest decision.
What factors should be considered when deciding whether to straight cut canola?
You should consider crop maturity, uniformity, weed presence, stresses like insects or weather and how well the pods are holding together. Thin or uneven crops and green weed material can also influence the choice between swathing and straight-combining.
When might using a pre-harvest aid be necessary before straight-cutting canola?
A pre-harvest aid may be used if the weather forecast is not favorable, there is a risk of early frost or you need to speed up crop and weed dry down for straight combining.
What are the main pre-harvest aids recommended for canola?
The Canola Council of Canada recommends desiccation with Diquat for fast drydown, pre-harvest glyphosate for perennial weed control and Heat LQ (Saflufenacil) for dry down and annual weed control.
Does a pre-harvest spray help accelerate the physiological maturity of canola plants?
No, pre-harvest aids do not quicken the physiological maturity of the plant. Their purpose is to dry down weeds and help prepare the crop for harvest, but they do not affect the plant’s physiological development.
What is the Pod DefendR trait and how is it assessed?
Pod DefendR is a shatter tolerance trait that helps with straight cut or delayed swathing harvest systems. Hybrids must achieve a shatter rating of 7 or higher on the Canola Council of Canada’s shatter rating scale to receive the Pod DefendR designation.
