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The Benefits of Flexible Roundup Rates
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The Benefits of Flexible Roundup Rates

May 06, 2019

Solid farm management plans and practices can help alleviate some of your spring stress, however life can always get in the way. Thankfully, another new tool is now available to deal with spray season pressures – TruFlex™ canola with Roundup Ready® Technology.

This new canola trait system provides improved weed control against tough-to-kill weeds like cleavers, foxtail barley, yellow foxtail and wild buckwheat. Also, if your spray dates are delayed, you can still get the job done with an application window that offers up to 10 to 14 more spray days than our current technology*.

In addition, advances in trait technology and genetics means you’ll get better weed control and crop safety compared to Roundup Ready® canola. This combination can help you see a higher yield potential at the end of the season.


Development of flexible application rates

Looking at field trial research during the development of the new trait, TruFlex canola showed the most promise in two distinct areas – crop tolerance and efficacy.

According to Tim Darragh, Technology Development Representative at Bayer Crop Science, the TruFlex trials displayed 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.

“This was a huge breakthrough during the trials and ultimately gives growers control over a greater number of weeds (24 in total), which are currently not on the label for Roundup Ready canola,” said Darragh. “The other nice thing about TruFlex is that it provides growers with more flexibility to target the right rate of Roundup required to control the weeds they have in the field and avoid over-application.”

In fields with smaller weeds and less pressure, growers have the option to apply 0.33 L/ac and still have great control. Likewise, with larger weeds, the grower can choose higher suitable rate with confidence in the crop safety profile of TruFlex. In terms of exact rates, Darragh outlines these three general guidelines:

  • Don’t apply more than 1.33 L/ac total in-crop.
  • When using sequential applications, they should be a minimum of 14 days apart.
  • When applying after the 6-leaf stage, no more than 0.67 L/ac should be applied.

Because of these flexible rates, farmers who are delayed during spray season are still able to control weeds without much risk to yield potential.


Flexibility in Spray Rates and Timing



Flexible rates = efficiency and stewardship

Darragh also points out that there are other benefits associated with getting the rate right and early application.

“By following the label rates and spraying early, farmers aren’t just being good stewards of the land, they’re also employing sound weed resistance management practices by ensuring fewer weed escapes and reducing the time and cost for spraying later in the growing season,” said Darragh. “This is better for the health of our fields, our crops and our bottom line.”


The gift of time

Darragh says TruFlex’s flexible rates and wider application window will also provide growers with more time to:

  • adapt to weather conditions;
  • manage expanding farm operations; and
  • control weeds in their crops, especially tough or emerging ones like yellow foxtail.

“TruFlex canola is going to provide growers with great opportunities to improve the efficiency and overall profitability of their operation. While the flexibility provides added breathing room, it shouldn’t come at the expense of sound farm management decisions,” added Darragh.

Darragh stresses that farmers still need to focus on early weed removal. The critical weed-free period for canola is up to the 4-leaf stage, so he recommends targeting a system that includes either a pre-seed burn off, or an early in-crop (cotyledon-to-1-leaf stage) application followed up with a second application later in-crop.

At the end of the day, to get the most out of TruFlex canola, growers still need to focus on solid agronomic practices.


To learn more about canola’s next generation, visit


* Compared to Roundup Ready canola.