A dual urease-and-nitrification inhibitor applied to a 155 lbs N/ac rate cut nitrous oxide emissions by 68% at AAFC's Tilbury site in 2024, while keeping corn yields intact.

How is the Living Labs network set up?

The five-year Living Labs program runs from 2023 through March 2028. Agriculture and Agri-Food Canada operates six trial sites in the Niagara-Essex region and three in Ottawa-Central Ontario, all running on commercial farms rather than research stations.

Soil biochemist Craig Drury, based at AAFC Harrow, said the design flips the usual trial format. "Living Labs is a little bit different in that you're designing the projects with the producer. It's tailoring management practices to fit within their operation and equipment," Drury said.

Research scientist David Pelster added that on-farm variability cuts both ways. "Each individual site might be a little more variable but you have a lot more sites than we otherwise would," he said. "With a research trial, your results might be specific to that particular field, whereas with [Living Labs] if you do see something we have more space to scale its applicability."

How big were the emission cuts?

Trials used a simple framework. Nitrogen went on at 180 lbs N/ac or 155 lbs N/ac, with or without a dual inhibitor, across 12 test strips per site.

At Tilbury in 2024, the four treatments produced these N2O reductions versus the untreated full rate:

• Full 180 lbs N/ac + inhibitor: 41% reduction
• 155 lbs N/ac alone: 61% reduction
• 155 lbs N/ac + inhibitor: 68% reduction
• Pelster's separate site with reduced rate plus inhibitor: 13% reduction

Lower rates did most of the heavy lifting on emissions at Tilbury. The inhibitor amplified the result when paired with a rate cut.

Did yields actually move?

Yield responses ran site-by-site. Pelster flagged one farm where the inhibitor produced "textbook" results on both nitrogen rates, lifting corn yields by four per cent across the board compared with untreated 180 lbs N/ac.

At that site:

• Lower rate + inhibitor: +5 bu/ac versus the untreated full-rate check
• Full rate + inhibitor: +7 bu/ac versus the same check
• Every inhibitor strip beat the untreated full rate

"If you want to lower the rate and keep the same yields, it showed that we had to have an inhibitor there," Pelster said. "It's not true in all sites, but there are some where it was textbook results in the way it worked."

Across southern Ontario Living Lab fields, dual inhibitors at standard rates added 7 to 10 bu/ac. One site returned 10 to 15 bu/ac when the inhibitor was paired with an 85% N rate. Separately, injecting UAN plus a dual inhibitor produced an 18% yield bump over standard broadcasting.

What does the economics look like?

Drury laid out the math at a summer 2025 AAFC webinar. An 18% corn yield lift — about 30 extra bushels per acre — at $6/bu delivers roughly $180/ac in additional gross revenue. The dual inhibitor costs around $20/ac, leaving the farmer well ahead.

• UAN + dual inhibitor in Living Lab trials: $34 to $41/ac extra profit
• Dual inhibitors enabled N-rate cuts of 15 to 20% without yield loss
• Lamothe's farm: positive ROI across every season of the trial

Norm Lamothe runs 500 acres of corn-soy-wheat-oats at Woodleigh Farms near Peterborough, Ont., a sixth-generation family operation. He rotational-grazes sheep on cover crops instead of spraying them off — a management move that put soil biology ahead of bagged biology from the start.

"What we found is it's not allowed us to reduce nitrogen, but it's made that nitrogen more efficient," Lamothe said. "So the dollar value of what we get back from the nitrogen usage and efficiency versus the price of the [inhibitors] has been positive throughout the trial."

Why does Drury push dual inhibitors specifically?

A urease inhibitor alone cuts ammonia volatilisation but leaves more nitrogen in the soil, which can lift N2O losses back up — a swap Drury calls "pollution swapping." A dual inhibitor suppresses both loss pathways and keeps more N available to the crop.

The case strengthens on wet, heavy soils. "If you have a heavier texture soil where you do often have very wet conditions, that's when it would have been beneficial to have applied a combined urease and nitrification inhibitor with your granular urea or liquid UAN fertilizer," Drury said.

He also pointed to a farmer who switched to injection after seeing the Living Labs data, even though he did not own the kit. The trial convinced him to arrange custom injection first, then consider buying the toolbar if the numbers worked.

What should Ontario corn growers try this season?

Lamothe's starting point is a single zero-N test strip fed into the Ontario Corn Nitrogen Calculator. The exercise defines each farm's minimum economic N rate before any inhibitor spend.

"I think all farmers farm the way they farm until they can farm better," he said.

AAFC will publish further Living Labs results before the program closes in March 2028. Site-by-site data is available on the Ontario Soil and Crop website (ontariosoilcrop.org/livinglab), and Drury's full 2025 nitrogen-management webinar sits on YouTube for growers weighing their next input pass.