Glyphosate is Canada’s top-selling pesticide, mostly used in agriculture as a herbicide and to desiccate crops for harvest. While it has come under increasing scrutiny in recent years, glyphosate continues to play an important weed management role on many western Canadian farms.

A study by University of Saskatchewan researchers suggests glyphosate has served another important function — making Prairie agriculture more sustainable.

For the research paper, called “Correlating Genetically Modified Crops, Glyphosate Use and Increased Carbon Sequestration,” co-authored by Chelsea Sutherland, Savannah Gleim and Stuart Smyth, 137 Saskatchewan crop producers were questioned in an online poll between November 2020 and April 2021.

“When we asked farmers in the survey which of the technologies contributed the most to sustainability, it was glyphosate. They said the efficient weed control provided by glyphosate in their crop rotations was really the fundamental thing,” says Smyth, a professor in the Department of Agriculture and Resource Economics at the University of Saskatchewan.

“That was definitely a bit of a surprise,” he adds. “I was expecting it to be the genetically modified canola and the GM corn and soybeans that have come in as well.”

In the survey, participants were asked how their land management practices had changed over the past 25 years.

A key finding was farmers had shifted away from cropping systems that utilized intensive tillage and summerfallow to no-till systems. This was due in part to the advent of glyphosate and the complementary technology of genetically engineered herbicide-tolerant crops in the 1990s, which meant producers no longer had to rely on tillage as their main form of weed control.

Smyth says the two technologies, by slashing the reliance on intensive tillage practices and summerfallows in favour of no-till systems, enabled farmers to boost sustainability through improved soil quality, less erosion and reduced fuel consumption and greenhouse gas emissions.

“Our objective was to establish good baseline data prior to the commercialization of genetically modified canola in 1995, so that we have the ability to compare apples to apples as to how innovative technologies have contributed to making agriculture more sustainable,” says Smyth.

“If we’re not doing that, then we can’t better inform policy-makers, at both provincial and federal levels, about the advances that agriculture is making due to better crop genetics, changes in chemical use and also in the equipment that enables a lot of this to happen as well.”

The research paper contends removing or restricting glyphosate or herbicide tolerance technologies would have an adverse effect on sustainability on Prairie farms.

“I think … what our research shows is that sustainability relies on a system,” he says. “In this systems approach, everything needs to work in harmony or in synchronicity with the other aspects for the whole system to be efficient or sustainable.”

Carbon sequestration

According to Smyth, the study also illustrates how glyphosate and herbicide-tolerant crops have been a main driver of increased carbon sequestration in Saskatchewan’s agricultural soil by facilitating the adoption of conservation tillage and reduced summerfallow practices.

“The removal of tillage and adoption of minimal soil disturbances has reduced the amount of carbon released from tillage and increased the sequestration of carbon through continuous crop production,” the research paper states.

“Through the virtually complete adoption of sustainable soil management practices, facilitated by innovative tools and technologies, including herbicide-tolerant cropping systems and the associated chemicals, Saskatchewan crop farmers are reducing the carbon footprint of their operations and contributing to Canada’s important climate objectives.”

Smyth says he believes Canadian ag is moving closer to some type of a carbon market at a national level, which would allow Prairie farmers to start extracting some financial value from sustainable practices they’ve been incorporating over the past 20-25 years.

“Our research highlights how the ability to keep your land in a continuous crop, zero-tillage rotation is really going to start to become a bit more fiscally profitable from a carbon sequestration perspective,” he says.

Click here for more Industry News.