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Setting Big Canola Yield Goals
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Setting Big Canola Yield Goals

Apr 12, 2019

Get the most out of your canola fields this growing season

While some factors for optimal yields are no-brainers (and possibly out of your control) like adequate moisture levels and ideal temperatures, others need to be deliberately planned and executed.



Unlocking the research for higher yields

A research review published in the January 2018 edition of Crop Science, summarized key management factors for determining canola productivity and maximizing potential yield.

The extensive study analyzed data available from performance trials across North America since 2011 and also incorporated over 100 reports from peer-reviewed journals, extension publications and websites over the past 20 years.

The review concluded that water supply, balanced nutrition, early planting (for both winter and spring canola) in shallow depth (10 to 19 mm), high seeding rate (6 kg ha−1), and diverse rotation (planting canola every 3 or 4 years) were among the best management practices to increase canola yields.

Other contributing factors to maximizing yields included effectively (and quickly) managing stress from weather, weeds and pests, and correctly timing swath and direct combining.


Survey says…

Also informing the review was data gathered from a canola grower survey conducted in 2011-12 by Agriculture and Agri-Food Canada (AAFC) and the Canola Council of Canada (CCC), which studied all the contributing factors to canola yield and best practices in canola management.

The data gathered from this survey found that using a soil test to guide nitrogen fertilizer rates provided the best yield advantage – with a 2.2 bushels per acre yield advantage over grower’s simply using past experience or yields as a guide.

Seeding earlier in the growing season also paid big yield dividends with a reduction of 3.6 bushels per acre in yield when the crop was seeded after May 22. However, there was no yield difference found when farmers seeded before the first week of May and the mid-May seeding dates.

Farmers who calibrated their seeding rate achieved 1.2 bushels per acre higher yield while those who swathed based on seed colour (about 73 per cent) had higher yields compared to those who swathed based on green seed count.

Overall, the results of the survey showed that maximizing canola yields relies on making sound management decisions that are based on both past experience and best practice.


Attack weeds early to maximize yield potential

Over the past 20 years, multiple research projects have found early weed removal produces higher yields in canola.

A study published in 2008, found the timing of weed removal had the greatest effect on canola yield – with weed removal at the four-leaf stage generating the highest yields in most cases. In fact, the report estimated that the yield effect of one weed emerging a week before the crop is equivalent to that of 100 weeds emerging three weeks after the crop.

The study also found that delaying weed removal until the six- to seven-leaf stage reduced canola yields by 20 percent or more.

To achieve proper weed control early also means that you’re helping to ensure good crop emergence and maintaining a uniform, even stand – which helps crops successfully compete against new weeds. Generally speaking, a good stand target is eight to 10 plants per square foot or higher to achieve a good uniform plant stand.


Weeds can be a compounding problem

Another impact on canola yields is the fact that drought and heat make some weeds stronger.

Various academic research papers have shown that a concurrent drought and heat wave increases the competitiveness of weeds growing in fields – and because many weeds have better water-use efficiency than crops – this means even less moisture gets to the plants.
(Patterson, 1995; Ziska et al., 2010; Valerio et al., 2013).

Weeds can also host crop diseases which can drastically impact yields. In the case of most plant viruses found in Western Canadian crops, there are three main sources:

  • transmitted seeds
  • infected transplants
  • naturally infected weed hosts or ones that originate in an adjoining infected susceptible crop

While not easy to control completely, the best way to keep viruses in-check is to quickly and effectively control weeds in your field.


A new canola system to manage weeds and increase yield potential

As spray season approaches (a notoriously stressful, frustrating and exhausting time), help has arrived in the marketplace. TruFlex™ canola with Roundup Ready® Technology is part of a new canola system designed to control many problem weeds (24 in total).

In the past, unpredictable weather during the spring spray season has threatened farmers’ ability to remove weeds early. TruFlex canola has a wider window of application than Roundup Ready® canola, so you have some breathing room if weather sidelines your spray plans.

TruFlex canola also provides improved crop tolerance to Roundup WeatherMAX® herbicide, which will allow growers to apply rates up to 1.33 L/ac in a single application or 0.67 L/ac in sequential applications.

Because of its flexibility in the application window and rates, the TruFlex canola system provides improved control of a broad spectrum of tough weeds like cleavers, foxtail barley and wild buckwheat compared to the Roundup Ready® canola system – and also helps enable season-long dandelion control.

With TruFlex canola, you can achieve weed control and higher yield potential in a way that works for your farm’s unique challenges. And, with that extra flexibility, you can care for your fields with confidence and put yourself in the best position to maximize your canola yield potential this growing season.





Assefa, Yared & Prasad, P. V. Vara & Foster, Chris & Wright, Yancy & Young, Steven & Bradley, Pauley & Stamm, Michael & Ciampitti, Ignacio. (2018). Major Management Factors Determining Spring and Winter Canola Yield in North America. Crop Science. 58. 16. 10.2135/cropsci2017.02.0079.

Harker, K., O'Donovan, J., Clayton, G., & Mayko, J. (2008). Field-Scale Time of Weed Removal in Canola. Weed Technology, 22(4), 747-749. doi:10.1614/WT-08-107.1