Set up an interview
Media Relations
Agriculture and Agri-Food Canada
1-866-345-7972
aafc.mediarelations-relationsmedias.aac@agr.gc.ca
Agriculture is at the heart of countless communities across the Prairies, supporting livelihoods and providing nutritious food for Canadians and the world. It’s also a vital driver of Canada’s economy, with the agriculture and agri-food sector in the Prairies contributing $22.5 billion in 2022. So, it’s incredibly important that we work to protect the health and productivity of our agricultural lands.
One of the biggest threats to cropland in the Prairies is something we’re all familiar with, from farmer to lawn enthusiast to hobby gardener: weeds. Weeds can be a problem because they compete for resources (like water, light and nutrients) with what we’re trying to grow, interfere with all sorts of things like soil health and irrigation, and can even upset the biodiversity of the ecosystem. And while not all weeds are harmful, some weed species are so invasive they threaten to run wild and take over large areas of land.
Fortunately, Agriculture and Agri-Food Canada’s researchers are coming to the rescue. A handful of weed researchers in the Prairies have formed a kind of Super Team. These humble heroes are working together to help farmers protect their fields from the wickedest weed villains in the West. Taking a multi-faceted approach, sometimes called integrated weed management, they leverage each other’s strengths and collaborate to discover more effective solutions. And while they all have different superpowers, by partnering together they form one formidable force in the fight against the most challenging weeds.
Julia Leeson: Weed watcher
Before you can tackle a problem, you must first understand it. Julia Leeson, weed monitoring biologist at the Saskatoon Research and Development Centre, conducts field surveys throughout the Prairies to get a clearer picture of what weeds are causing problems in producer’s fields. Think of her as a hall monitor for misbehaving weeds: she helps track which weeds are the biggest trouble-makers, and where they are gathering.
Because weeds know no boundaries, it’s important that everyone in the agriculture industry work together to monitor their progression across the landscape and share information on best practices in combating them. This is part of a system called biovigilance.
Leeson works closely with provincial partners to monitor and map weed infestations, and also looks at weeds in different types of agricultural systems – for example, one project she is involved with is looking at the impact of natural and planted field boundaries on weeds, while other projects explore the interplay of weeds with organic production systems.
The Prairie weed survey takes place over a four-year period, when over 4,000 fields are visited across the agricultural areas of the three Prairie provinces. The surveys have been conducted similarly for the past 50 years, allowing comparison and assessment of changes in the weed populations.
Charles Geddes: Kochia warrior, field champion
Sometimes, the more you attack a problem weed, the stronger it becomes. Like a villain in the movies that just keeps getting bigger and more powerful with everything the heroes throw at it, some weeds are masters at adapting to common weed management tactics like herbicide. For example, Dr. Charles Geddes, research scientist at the Lethbridge Research and Development Centre, has been studying weeds that no longer seem to be affected by the common crop treatments producers spray in their fields. This is called herbicide resistance, and kochia (a bushy, invasive weed capable of producing 30,000 seeds in a single plant) is one of the prime examples of this challenge.
Kochia has proven to be a worthy adversary. Blowing up from the southwest, often in the form of tumbleweeds, it’s prevalent in fields throughout the Prairies, particularly in southern Alberta and western Saskatchewan. In some areas, this troublesome weed has evolved throughout the years to be resistant to many traditional classes of herbicides. Its ability to adapt makes it not only difficult to control, but also stronger and more resilient, allowing it to out-compete crops and spread more rapidly. Dr. Geddes has been exploring ways to control weeds like kochia by making them once again vulnerable to the safe and economical crop treatments that most producers use. He is researching whether we can alter the genetic make-up of the weed, to turn back the clock on some of the rapid adaptation kochia has benefitted from – turning the lion back into a kitten and enabling producers to take back control of their fields.
And because we know that we can’t fight what we don’t understand, Dr. Geddes also works very closely with Julia Leeson to survey producers. The survey data shows a clearer picture of where herbicide-resistant weeds are present, and helps track how resistance is spreading. This data is invaluable to our Super Team of weed researchers, so they can help farmers add the right tools to their kits and better manage weeds in their fields.
Shaun Sharpe: Smoking out the enemy
The work of Dr. Geddes and many other researchers has made it clear that managing weeds requires more than just herbicide. While spraying crops is still an important tool for producers, a combination of approaches is necessary to both minimize herbicide resistance and improve production for farmers.
Dr. Shaun Sharpe, research scientist at the Saskatoon Research and Development Centre, is also answering the call to discover new weapons in the battle against weeds. Key to Dr. Sharpe’s work is the idea of reducing the infestation of weeds in the first place, before they have a chance to replenish themselves and overpower herbicides.
One project he is working on involves stimulating weed seeds to emerge in the fall and then relying on frost to kill the delicate young plants. This would render those seeds unable to re-grow in the springtime, thereby reducing their impact on the next year’s crop.
But how would a superhero stimulate the enemy weeds to grow? X-ray vision? Lightning bolts? No - with smoke, of course! Actually, not real smoke, but a compound also known as pyroligneous acid or wood vinegar, which is derived from burning plant materials. This is more commonly known to sausage-making enthusiasts as flavouring agent liquid smoke. Pow, take that, weeds!
But why does smoke stimulate plant growth? Although it is still being studied, researchers believe it may provide a “scorched earth” survival signal, as seen through the rapid regrowth of plant communities following a fire. In this application, the idea is to stimulate seeds to grow at the “wrong” time of year and then die off, which would drive down their density in the seedbed over time. The result: fewer weeds to kill means less resistance risk for herbicides.
Dr. Sharpe is currently investigating wood vinegar in greenhouse settings, with the hope that an appropriate pattern of application timing can be identified for larger-scale field trials.
This is just one of the new approaches Dr. Sharpe is cooking up in his lab. He and the rest of the Super Team are exploring all aspects of weed control, including interrupting their growth cycle before they can become a big problem.
Breanne Tidemann: Dealing the crushing blow
Since we now know we can’t “spray our way” out of weed issues, Dr. Breanne Tidemann, research scientist at the Lacombe Research and Development Centre, is also focused on studying multi-faceted strategies in the battle against weeds. One of these solutions is harvest weed seed control. This tactic has been prompted by our growing awareness of herbicide resistance – which, thanks in part to the work of our Super Team, is becoming clearer.
The idea behind this management approach is that many weed species are producing seeds at the same time the crop is becoming ready for harvest. During harvest, these weed seeds are spread far and wide, ready to pop up and cause problems in future years – mo’ seeds, mo’ problems. So, it makes sense to try and limit these little menaces before they have a chance to wreak havoc. One tool Dr. Tidemann has been experimenting with is physical impact mills. This piece of equipment separates the weed seeds from the crop and literally crushes them, making them harmless and unable to grow the next year.
One of the challenges for producers to adopt this approach is cost – currently, buying this equipment comes with a fairly high price tag. So, Dr. Tidemann is working on both demonstrating the effectiveness of this strategy (so producers can decide for themselves if it has value to their operations) and exploring less costly ways that producers can control harvest weed seeds in their fields.
Overall, Dr. Tidemann is hoping this can be one more tool in the box for farmers and she’s excited to continue working with the Super Team to discover other new solutions for Canadian producers.
The Super Team is on the case
These are just some of the ways AAFC scientists are thinking outside the spray, and helping producers take back their fields with new, effective integrated weed management strategies. By working together, they continue to come up with innovative ways to build off each other’s work and design new weapons in the battle against weeds. In fact, this work is happening all across the country in many crop types, such as studying projectile weed control: Canada's weed hunters set their sights on natural alternatives to herbicides.
Managing weeds can be a complex challenge, but finding solutions is critically important. Canadians and people around the world rely on the food our farmers produce. With 80% of the farmland in Canada located in the Prairies, we are fortunate to have this Super Team of weed researchers on the case, helping our farmers and producers battle their biggest weed foes.
Key facts
- Managing weeds is a complex challenge, but our Super Team of weed researchers in the Prairies is working together to discover new ways for producers to protect their fields.
- Taking a multi-faceted approach called integrated weed management, these researchers leverage each other’s strengths to help farmers add the right tools to their kits to better manage weeds.
- By collaborating with each other and other researchers, the Super Team is learning more about the weeds in producer’s fields and finding new, practical solutions that enhance the effectiveness of traditional weed management methods.
Photo gallery
