The partnership pairs Geco’s predictive mapping tools with Gowan’s line of soil-applied herbicides in a collaboration aimed at helping farms take a more deliberate, patch-based approach to weed control over multiple seasons.

WHY IT MATTERS: Seeing weed pressure ahead of emergence can make herbicide decisions more targeted and cost-effective.

Geco’s announcement includes two offerings tied to the partnership. The company is launching a new three-season predictive-mapping subscription, and growers who sign up through a Gowan representative will receive one additional field map at no extra cost.

“Our technology enables the question: If you could know where your most problematic patches are and where they are spreading to, what could you do differently? That’s what our technology makes possible,” said Greg Stewart, CEO of Geco.

How predictive mapping works

While blanket applications and spot sprayers respond to weeds already visible in-season, predictive mapping works ahead of emergence by using multi-year imagery to identify the areas most likely to develop patches. That allows farms to be proactive with treatments, rather than reacting after they’ve already gained ground.

A grower wanting a map begins by sharing a field boundary with Geco, often through a platform like John Deere Operations Center. If they don’t have a boundary available, Geco can make one for them. From there, Geco pulls every usable satellite image of that field from the last five growing seasons and runs them through tools designed to distinguish crop from weeds across the full season.

That multi-year history is what drives the prediction. Stewart said the key isn’t ultra-high-resolution imagery as much as having dozens of images per season and several years of history to reveal how weed patches shift over time.

The history shows where weeds tend to emerge early or flush late, and where patches persist. The resulting prescription can be exported straight into a sprayer, granular applicator, drill or variable-rate seeding tool.

“We look at a field, understand where weeds have been and where they’re going, and from there the farm decides what to do,” he said.

Geco has calibrated its system by comparing predictions against drone imagery, spot-sprayer data and human scouting across many fields.

Because the algorithms used to make these calibrations and predictions are proprietary, Stewart was tight-lipped about their inner workings. But while they play a big role in the process, he says the real challenge is fitting the technology into a farmer’s season.

“It’s not usually the math that breaks these technologies,” he said. “It’s how well you solve a real-world problem.”

That means making sure the system fits farm reality. It must mesh with timing at the end of the season and fold naturally into a grower’s weed-control plan. Those practical points tend to matter more than the complexity of the algorithm.

That’s also where partnerships come in. Predictive maps don’t work in isolation; they need to line up with the herbicides and practices growers are already using in the field.

Many early adopters were already using chemistries such as ethalfluralin and triallate (the active ingredients in Gowan’s Edge and Avadex) on their worst kochia and wild-oat patches. Those products are expensive to blanket across entire fields, and predictive maps help target them only where they’re most likely to deliver a return. So, the collaboration made sense for both companies.

But herbicides are only one part of the equation, said Stewart. Once the map is made, growers still need a plan for how to use it: which products to place where, when to increase seeding rates and how to tackle the “problem-child” areas that keep showing up year after year.

“It’s the agronomist and the farmer who put together that strategy,” he said.

For Warkentin, predictive mapping works best on fields with well-defined patches like those same “problem-child” zones mentioned by Stewart. Once he receives a map, he reviews it with the grower to confirm the predicted zones match field history and scouting. He then adjusts rates, creates the prescription file and loads it into the sprayer or applicator.

There are still some practical limits — the kind Stewart refers to when he talks about real-world barriers. For example, some older spreaders can’t run prescription maps. Fortunately there is an easy workaround: growers can load the files into Google Maps. However, Warkentin says timing is a more stubborn problem for farmers.

“The best time to look at these maps is after harvest, but that’s also the busiest time of year,” he said. “By the time fall work is done, there’s very little time left to get maps made up and implemented.”

For farms using higher-value soil-applied products, the economics work well. Targeting only the worst 20 or 30 per cent of the field makes premium herbicides more economical and reduces total chemical use. Farms using lower-cost products may see less financial benefit, since the price of generating a prescription can outweigh the savings from variable-rate application.

However, Stewart noted that most growers use the maps to intensify control in the toughest patches — not necessarily to cut total inputs.

Either way, Warkentin says growers who used the maps were pleased with the results.

“The system isn’t perfect, and producers know there will be a few small misses,” he said. “But overall the people who’ve used it have been happy with the results.”

For weed scientist Charles Geddes of AAFC Lethbridge, predictive mapping fits within a broader integrated weed management approach. He sees it helping growers make more deliberate decisions about where to invest their time, herbicides or cultural practices.

“I see this as another tool in the toolbox farmers have at their disposal,” he said.

Weed pressure is becoming harder to manage due to expanding herbicide resistance and weather variability that affects herbicide performance. Geddes says predictive mapping can help farmers plan where residual herbicides or added competition may provide the biggest returns. Using herbicides that stack multiple modes of action can be costly, especially on dryland farms, and applying them across full fields isn’t always justifiable.

“Predictive mapping lets farmers target herbicides or other practices where they’ll have the greatest impact,” Geddes said. “That can go a long way toward managing both costs and resistance.”

He also notes the technology adds some complexity. Prescription mapping requires growers to manage another layer of planning at a time of year when workloads are already heavy. That may limit adoption for some operations. But he expects interest to grow as farms gain experience and as more tools in crop production move toward AI-driven decision support.

That Prairie focus shapes where the technology goes next. Stewart says the company is now putting more emphasis on building partnerships with local retailers, agronomists and farmers to support longer-term, multi-season weed strategies. The Gowan partnership is just one example.

“We’re starting to partner with other retailers and independent agronomists across the region,” he said. “We’re really developing those relationships as much as we can these days.”

The post Predictive weed mapping, coming to a farm field near you appeared first on Manitoba Co-operator.

The 49-question online survey was conducted between the spring and fall of 2023. A total of 10 producers from Alberta and Saskatchewan who were early adopters of the technology responded to the survey. The results of the study were published in the September 2024 edition of the Canadian Journal of Plant Science.

Why it matters: Mechanical solutions like weed seed destructors have gotten some attention due to weed resistance concerns, but uptake on the Prairies has been slow.

You may know what a weed seed mill is, but you may not know how it works.

Here’s a snapshot of what it does and how it helps prevent weeds from growing and spreading.

First, the mill is attached to the rear of a combine. Then as a crop is harvested, weed seeds come out of the back of the combine and are fed into the mill where they are spun at a high rate of speed, which damages the weed seeds and renders them nonviable. This material is then spread back in the field.

In addition to controlling weed seeds, the mills also help stop the spread of weed seeds during harvest, lower herbicide costs, and reduce selection pressure for herbicide resistance.

Some of the most popular HWSC devices include the Redekop Seed Control Unit, the Integrated Harrington Seed Destructor, the Seed Terminator and the WeedHOG.

Making it work

While there have been various Canadian studies on impact mills, this is the first one to look at harvest weed seed control (HWSC) that incorporates actual on-farm experiences.

AAFC research scientist Breanne Tidemann says even though researchers had previously conducted small-plot research and field trials on HWSC technology, there were some knowledge gaps and it was important to gather real world data about its use.

“No matter how much small-plot research or even field trial-scale research you do, it’s not the same as a farmer using it on all their acres for multiple years,” says Tidemann, who led the research study.

“They just get insights and experiences that we can’t get.”

Tidemann says while the survey used a relatively small sample size, the 18 weed seed mills that were part of it represented 60 per cent of the machines estimated to be in used in Canada in 2023.

Those results, she adds, will provide a baseline that researchers will be able to revisit down the road to determine changes to the adoption rate and who is using the technology.

The study focused on several key issues including who is using HWSC technology and why; challenges they have encountered with it; crops it is being used with; maintenance and fuel costs and how effective it is in controlling problem weeds.

The survey results indicate most of the responding producers who use the physical impact mills for HWSC operate larger farms (10,000 acres or larger). Those producers equipped a majority of their combines (75 per cent) with the mills, but acknowledged they were strategic about their use since they had a limited number of the machines available.

Survey respondents indicated wild oat (60 per cent) and kochia (50 per cent) were the top weeds that motivated them to adopt impact mills on their farm.

Tidemann says she was somewhat surprised to see wild oat ranked so high.

“All the research that we’ve done has shown wild oat loses its (weed) seeds early, so there’s some challenges using harvest weed seed control for wild oat. But I’m not surprised that it’s pushing people to try alternatives,” she noted.

The survey results also indicated operating a weed seed mill behind a combine adds an additional $1.40 in fuel costs per acre. Tidemann says it’s up to individual farmers to determine how affordable that is, since it largely depends on the size of the farms they operate.

On average, producers said it cost them about $1,500 a year in maintenance per impact mill, including greasing the mill as well as changing parts such as bearings and belts. Tidemann says it was difficult to pinpoint a precise figure since many respondents had only recently adopted the technology and were estimating what their costs would be. Longer-use adopters who completed the survey indicated annual maintenance costs of about $1,750 for each unit.

Participating producers were also asked about limitations or challenges they experienced when using the mills on their farm. Most respondents (70 per cent) identified mill plugging due to green material as a significant limitation they encountered. One of the primary sources of green material identified in the survey was kochia.

“A very large patch of kochia that’s essentially choked out all the crop, if you try and take that in one fell swoop, you will be unplugging the back of your combine. There’s got to be enough dry materials to push it through,” Tidemann says.

Despite that, a number of respondents identified kochia as the weed that showed the greatest response in terms of mill use. They also noted reduced use of herbicides with grassy weeds such as wild oats and green foxtail when using an impact mill. Wheat (90 per cent), canola (80 per cent) and lentils (80 per cent) were identified as the crops in which mills were most utilized.

Producers were also asked to estimate how long it will take to recoup the investment they made when they purchased an impact mill. The most common response was three to five years (60 per cent) followed by six to eight years (20 per cent).

“It’s reassuring that those people that are adopting are going in with the mindset that it’s going to take some time and they’re not expecting an immediate response which is going to lead to people stepping out of it before they would maybe see the impact,” Tidemann says.

Respondents were asked to identify sources of information they consulted when considering the use of impact mills on their farm. The two most common responses were manufacturers/retailers and other early adopting farmers.

“The mill companies makes sense,” says Tidemann. “The second one, early adopting farmers, was interesting. To me, what that’s saying is it’s all good and fine to have someone like me out talking to them, but you’re going to get a whole lot more bang for your buck if you have a farmer that’s actually using the thing. They want to hear from farmers who are using the machines.”

Resisting resistance

Jason Waldenberger was one of the farmers who participated in the AAFC study. He operates a 6,500-acre grain farm just north of Moose Jaw, Sask., and has been using an Australian-manufactured Seed Terminator impact mill for the past three harvests.

Waldenberger says he’s an “easy sell” when it comes adopting new technology and became interested in HWSC equipment several years ago after meeting a fellow farmer who was already using it. He was prompted to start using it himself after noting growing chemical resistance among weeds in the fields where he was growing pulse crops.

He says participating in the study was a no-brainer, since anything producers can do to help the research community also helps themselves.

“We’ve got some fantastic people working in our industry,” he says. “I think anytime we can work with those kinds of people or pass along information and vice versa, they can then do really good, steady work and help us make better decisions and give us feedback on what they’re finding.”

Tidemann says the data gathered through the survey could help manufacturers make adjustments to their products to address some of the concerns producers raise.

It may also help provide some direction for future research in terms of HWSC technology.

Survey respondents were asked to identify research that was still needed regarding impact mills. The three most common responses were efficacy on weed densities, their impact on precision spraying and grain loss calculations.

“There’s still lots of things that we don’t know (about the technology) and this gives us an idea of what’s important on-farm,” says Tidemann.

The post The real talk on weed seed destructors appeared first on Manitoba Co-operator.

That was one message from Wes Lewis, Manitoba sales representative with Gowan Canada, during Manitoba Agriculture’s Crop Talk webinar in early October. Having spent more than 16 years in the agriculture industry, Lewis knows his herbicides.

“Our objectives with Gowan are to help growers manage weed resistance through the 2025 crop year,” he said. “But not just through then – to manage weed resistance in general.”

Why it matters: Fall weed control is more important this year because wet conditions this spring prevented many producers from spraying at the best time.

Kochia has been a persistent problem for years. It pops up in saline patches and has a biological proclivity for overcoming chemical control. Glyphosate-resistant kochia had made its mark in Manitoba over the last decade.

“This year it was really evident,” Lewis said, adding that wild oats were also a problem.

Both weeds are top of mind in the resistance conversation: kochia for its creeping victory over Group 9 chemistries and wild oats for their widespread resistance to Groups 1 and 2.

“We need to use as many tools as we have within the industry and as growers to really help fight back the resistance that is a problem,” Lewis said.

Product breakdown

Avadex (Group 15) and Fortress (Groups 3 and 15) are ahead of some resistance worries, for now.

Both are marketed by Gowan as a pre-emergent base in spring herbicide layering to relieve pressure on in-crop application. Avadex is noted in particular for resistance management in wild oats. Both are also used in fall.

Proper rates, record keeping and good crop and herbicide rotations are important, said Lewis. Avadex, Edge (Group 3) and Fortress have unique benefits in terms of management.

“When you’re looking at these benefits … from a resistance management standpoint, they’re effective. They’re unique groups, and growers are starting to incorporate them more.”

Avadex and Fortress create a herbicide layer in the soil, which is crucial to control wild oats, Lewis said. While Avadex focuses on shoots, Edge focuses on roots. With Avadex, the goal is for weeds to grow through the herbicide layer, which kills them.

Fortress does the same thing, but also focuses on broadleaf weeds. A clay carrier helps bring the product through stubble and in contact with the soil, where it binds to create the key herbicide layer.

To assess the effectiveness of these products, farmers can conduct soil scrapes, in which they peel back the top layer of soil to see if the product is working.

When it comes to application guidelines, Lewis said proper timing and method are important for optimal results.

Fall 2024

Early October was the ideal time to start fall applications, he noted, particularly in light of favourable weather conditions.

“We’ve had a really nice fall where temperatures have been really warm and quite nice. The harvest is well underway and kind of nearing wrapping up, and it should allow growers an opportunity to get onto their fields this fall and get those applications done and get prepped for 2025.”

Spraying later is also acceptable.

“Better to have some product on and know you’re going to get some protection moving into the spring,” Lewis said, emphasizing the unpredictability of spring weather.

Shallow incorporation is key for effective herbicide action — half an inch for Avadex and Fortress. Producers should aim for a uniform layer across this depth. With Edge, depth could be a quarter of an inch to a half-inch, Lewis added.

Soil moisture and stubble conditions are important. Proper incorporation will maximize effectiveness. In heavy stubble, it’s difficult to get the microactives in the herbicide down to the soil, Lewis said. Excess straw should be managed before application.

For minimum or vertical tillage systems, it’s best to apply the product after tillage, Lewis said. Soil lumps can hamper herbicide penetration.

Incorporation is necessary, since the microactives have low water solubility. Applying them on the surface isn’t sufficient, and volatilization can diminish herbicide effectiveness. That’s why adequate soil moisture is so important, Lewis said.

He warned that the noted products should not be used after field burning, since high carbon content can tie up active ingredients and reduce performance.

The post Best fall spraying practices to beat back herbicide resistance appeared first on Manitoba Co-operator.