Fall herbicide applications can be an important tool to kill weeds like Canada thistle.

Your overview of pre- and post-harvest herbicide applications

Q & A with an expert

Q: What can I do to control perennial weeds on my farm?  A: Late or end-of-season herbicide applications present growers with an opportunity to gain long-term control over tough-to-kill perennial weed populations.  The main goal of this application should be weed control and not hastening crop maturity. In fields with weed populations composed of quackgrass, […] Read more

I bioassayed soil in January from a field treated twice with the herbicide tribenuron-methyl in 2020 to determine if the field was suitable for a canola crop this year. It was not — the potted field soil fried the canola seedlings, which is shown in the photo at bottom. The photo at top is the check. I recommended the farmer stay with wheat this year on this quarter.

Herbicides and bioassays

A dry fall followed by a dry spring may leave much higher levels of residual herbicides

When you use a soil-persistent herbicide, there are many factors you must consider very seriously. The first thing you have to do is read the label that comes with the herbicide. It will tell you how to mix and apply, water source, what weeds are controlled and so on. Read it very carefully. Of course, […] Read more


Big Canada thistle plants can spell trouble in the combine, especially when there are large patches of them.

Fall herbicide application timing in canola

To control perennial weeds in canola, there are benefits to both pre- and post-harvest control options — the deciding factor could be tied to your goals

When deciding between a pre-harvest or post-harvest spray application to control tough perennial weeds, there are always some key considerations for farmers. The extent of the weed problem and harvest timing are important ones, of course, but other factors such as herbicide cost and killing frost also play into the decision. To control a weed […] Read more

To hit up problem weeds, such as herbicide-resistant kochia (far left photo), Alberta farmer Dallas Vert applies a post-harvest weed control treatment of Valtera. Last year, Saskatchewan farmer Dallas Leduc’s post-harvest application of Roundup ProActive 360 tank mixed with four ounces of 2,4-D worked well on Canada thistle (middle photo) and narrow-leaved hawk’s beard (right) on his farm.

Zap troublesome weeds in the fall

Whether it works best pre- or post-harvest depends on several factors

A sampling of western Canadian producers, when asked about their fall weed control measures, have most generally agreed that either a pre- or post-harvest herbicide application is a valuable management tool. Most of the farmers contacted leaned toward a post-harvest treatment with a glyphosate product, although there are a number of caveats that come into […] Read more


John Deere’s See and Spray Select option activates an individual spray nozzle only when boom cameras detect a green, growing weed below it.

Deere launches new See and Spray Select technology

Automated spot-spray option can reduce herbicide use

It’s no surprise to farmers that herbicide use in agriculture has come under increased scrutiny by the general public in recent years. In some countries, glyphosate may soon be banned entirely, which will cause significant adjustments to cropping practices. And even in those regions where there isn’t yet a risk of losing glyphosate, weed resistance […] Read more

Mike Cowbrough is the weed management lead, field crops, with OMAFRA and co-curator of sprayers101.com. In the photo, Cowbrough shows his audience how mixing order can affect product compatibility in tank mixes.

Two more reasons to consider a jar test before tank mixing

It’s better to be safe than sorry when you combine multiple modes of action or include micronutrients in the tank

When tank mixing goes well, farmers can reduce the number of passes through their fields, saving equipment operating time and man-hours, reducing compaction and optimizing application timing. When tank mixing goes badly, however, the results can be disastrous. Because chemical companies won’t and, in fact, can’t test their products with every possible mixing option, making […] Read more


Weed control options should factor into cropping plans

Weed control options should factor into cropping plans

Q & A with an expert

Q: What do I need to think about when planning for weed management? A: It is this time of year when acres are being locked into place for the upcoming growing season. With commodity prices currently on an upward trajectory, many different cropping options are being considered. Crops like flax, field peas and soybeans have […] Read more

Provincial weed specialist Clark Brenzil says Saskatchewan may be coming out of a dry cycle in 2021, which means that C3 weeds, such as wild mustard (shown here) and wild oat could do better this year.

How will you prep your fields this spring for best weed control?

What you need to know heading into Plant 2021

Farmers need to be on their toes to keep weeds in check and prevent crop injury this spring due to environmental conditions last year and those developing now. To help make the job easier for you, Grainews reached out to weed specialists in each province for their recommendations this spring season. Alberta In Alberta, Agriculture […] Read more


Franck Groeneweg and his family moved to Montana after 18 years of farming at Edgeley, Sask. It’s just over a year now since the family settled on their new 15,000-acre grain farm. This year, Groeneweg plans to apply a pre-seed burnoff,  which may include glyphosate likely tank mixed with 2,4-D, or he may apply a Fortress-type product that includes dicamba and tribenuron, but it will all depend on the weed spectrum in the field.

Weed control efforts off to a good start

There’s more than one way to approach spring weed treatments — Prairie producers discuss their strategies to control competitive weeds

Weed pressure usually isn’t too serious of a problem for most western Canadian crops in March or even early April, especially if there is still snow on the ground, but it’s a topic on many farmers’ radars as they plan for the coming growing season. For several producers in Western Canada, talking about weed control […] Read more

Figuring out all the angles on rotation can be a complex challenge for farmers.

Rotation, rotation, rotation are a farmer’s best friend in the field

Not rotating crops and chemistries might just be the opportunity crop pests were waiting for

[UPDATED: April 1, 2021] Rotation isn’t a new word, but applying it to all aspects of annual crop production might be a newer concept for western Canadian farmers looking to keep a step ahead of various crop pests, say specialists with Corteva Agriscience. A proper crop rotation, a proper variety rotation, a proper herbicide rotation, […] Read more