Map: Survey Shows Low DON Levels in 2024 Ontario Corn Crop

Oct 23, 2024

An annual survey conducted by the province suggests few vomitoxin concerns with this year’s Ontario corn crop.

Released this week, the results of the Ontario corn ear mould and mycotoxin survey showed more than three-quarters (76%) of the 261 total samples tested below 0.5 parts per million for deoxynivalenol (DON). Last year, only 41% of the samples tested below 0.5 ppm. At the other end of the scale, none of this year’s samples tested above 5 ppm, compared to 5% in 2023.

All told, 94% of the 2024 samples tested at 2 ppm or lower, versus 77% last year and the 10-year average of 86%.

The 2 ppm level is generally considered the maximum threshold at which DON levels are not a significant quality or marketing concern. The larger percentage of this year’s crop below that level indicates producers should not run into grade discounts, depending on the local severity of the problem.

As the map below shows, the bulk of this year’s more elevated DON levels (between 2 and 5 ppm) showed up in pockets in the southwestern part of the province, including Middlesex, Oxford, and Elgin counties, although some cases in eastern Ontario were also identified.

Farmers should evaluate their crops and consider harvesting and drying higher risk fields before infections worsen, the report said. Ear moulds and mycotoxins occur every year in Ontario and fields need to be assessed individually, it added.

“Even with 94% of 2024 samples testing below 2 ppm, growers should still be vigilant, as they may have individual fields with elevated DON.”

One of the worst years for DON levels in the Ontario corn crop was 2018. In that year, just one-third of the samples tested below 0.5 ppm, while 25% were at 5 ppm or above. A significant portion of the 2018 crop turned out to be virtually unmarketable, costing producers millions of dollars in lost sales. Farmers experienced another difficult year for DON in 2016, when less than half of the samples tested at 0.5 ppm or below.

Click here to see more...

Video: From Conventional to Regenerative: Will Groeneveld’s Journey Back to the Land

"You realize you've got a pretty finite number of years to do this. If you ever want to try something new, you better do it."

That mindset helped Will Groeneveld take a bold turn on his Alberta grain farm. A lifelong farmer, Will had never heard of regenerative agriculture until 2018, when he attended a seminar by Kevin Elmy that shifted his worldview. What began as curiosity quickly turned into a deep exploration of how biology—not just chemistry—shapes the health of our soils, crops and ecosystems.

In this video, Will candidly reflects on his family’s farming history, how the operation evolved from a traditional mixed farm to grain-only, and how the desire to improve the land pushed him to invite livestock back into the rotation—without owning a single cow.

Today, through creative partnerships and a commitment to the five principles of regenerative agriculture, Will is reintroducing diversity, building soil health and extending living roots in the ground for as much of the year as possible. Whether it’s through intercropping, zero tillage (which he’s practiced since the 1980s) or managing forage for visiting cattle, Will’s approach is a testament to continuous learning and a willingness to challenge old norms.

Will is a participant in the Regenerative Agriculture Lab (RAL), a social innovation process bringing together producers, researchers, retailers and others to co-create a resilient regenerative agriculture system in Alberta. His story highlights both the potential and humility required to farm with nature, not against it.