Innovations often completely transform systems of production. The invention of production lines transformed automobile manufacturing. The innovation of cellphones transformed people’s ability to communicate. Similarly, the innovation of genetically modified (GM) canola in the Canadian Prairies transformed crop production systems.
Transitioning to Continuous Cropping and Reduced Tillage Practices
The ability to efficiently control weeds through herbicide applications rather than through tillage transformed crop production. Historically, the use of tillage was the leading form of weed control, with many fields producing a crop one year only to be tilled numerous times the following year as part of the practice of summerfallowing. Summerfallowing is when a field is not seeded to a crop and tilled multiple times through the spring, summer and fall to prevent weeds from growing and going to seed. The number of tillage passes would depend on the amount of rainfall during a growing season. The greater the amount of rain, the greater the number of tillage passes.
The commercialization of GM canola in the late 1990s transformed in-crop weed control. Farmers could plant herbicide tolerant canola into weedy fields, spray the crop post-germination and receive efficient control of weeds, especially weeds that can be difficult to control such as thistles and wild oats. As the adoption of GM canola grew, farmers consistently experienced superior weed control through continuous cropping practices, removing the vast majority of summerfallow acres and tillage passes. Between the periods of 1991-1994 and 2004-2006, the use of tillage decreased 62%. By the 2020-2024 period only 1.4% of Saskatchewan crop acres included summerfallow.
Changes in SOM Levels
The frequent use of tillage and summerfallow practices resulted in lower levels of soil organic matter (SOM). Historically, Saskatchewan SOM levels ranged from 5.16% and 5.57% in 1889 at Maple Creek, to 12.74% in 1891 and 13.54% in 1897 at Saltcoats, and 13.27% in 1891 and 14.01% in 1897 at Yorkton. Over the course of the 20th century, the levels of SOM consistently declined across the province.
Both reductions in tillage passes and summerfallow practices have contributed to increases in overall SOM levels. A survey of Saskatchewan farmers collected data on SOM percentages dating back to 1990. Between the periods of 1990-1999 and 2015-2024, the average percent of reported SOM in the soil increased from 3.33 to 4.71, an increase of 41%. Looking specifically at the survey time periods, average reported SOM levels increased by 19% between 1991-1994 and 2004-2006 compared to 26% over the most recent 20 years. The following figure illustrates this increasing trend in the average reported percentage SOM in agricultural soils.
Benefits of Higher SOM Levels
The farmer survey identified an increase in yields of the most commonly grown crops in Saskatchewan: wheat and canola. During the period of 1991-1994, wheat yields reported by participants averaged 34.6 bushels per acre (bu/ac), rising to 50.7 bu/ac from 2020-2024, an increase of 47%. Similarly, canola yields increased from 27 bu/ac on average from 1991-1994 to 40.4 bu/ac between 2020-2024, an increase of 50%. The observed increase in yields cannot be credited to any single factor, but rather are a result of the system of agricultural innovations over the study period, as well as variable precipitation between crop years. These innovations include improved crop genetics such as GM crops, as well as improvements in pesticide and fertilizer technologies. Innovations in implements have also contributed to this, such as with the ability to use variable rate applications for fertilizer across a field, based on nutrient requirements.
Greater SOM levels provide additional crop benefits, such as reduced erosion and increased moisture conservation. Increased SOM has dramatically reduced soil erosion by both wind and water. The reduced water erosion prevents fertilizer nutrients and pesticide residues from leaching into watersheds, providing additional environmental benefits. Higher SOM levels and the increased presence of post-harvest residues contribute to providing an insulating layer of material that reduces moisture evaporation rates during period of intense heat.
Some environmental activist organizations are spreading false information about the environmental benefits of continuous cropping and the use of herbicides to control weeds rather than the use of tillage. These activists groups publish reports that are not peer-reviewed, often using flawed methodologies to assess data and advocate results that aren’t supported by the data. Our peer-reviewed research quantifies the improvement of soil health following the transition to continuous cropping and chemical weed control systems, soundly refuting the false information spread by activist organizations.
To check out the full, open access article titled “Impacts of reduced tillage on soil health in Saskatchewan”, click here
Sutherland, C., S. Gleim, and S.J. Smyth. (2026). Impacts of reduced tillage on soil health in Saskatchewan. Environmental Challenges, 24(101613). https://doi.org/10.1016/j.envc.2026.101613
Facts Only
* The invention of production lines transformed automobile manufacturing.
* The innovation of cellphones transformed people’s ability to communicate.
* The innovation of genetically modified (GM) canola transformed crop production systems in the Canadian Prairies.
* Weed control shifted from tillage to herbicide applications via GM canola.
* Summerfallowing involved leaving a field unseeded and tilling multiple times to prevent weed growth.
* Tillage passes historically depended on rainfall; more rain meant more passes during summerfallowing.
* Commercialization of GM canola allowed planting into weedy fields followed by post-germination herbicide spraying for weed control.
* Between 1991-1994 and 2004-2006, the use of tillage decreased by 62%.
* By 2020-2024, only 1.4% of Saskatchewan crop acres included summerfallow.
* Saskatchewan SOM levels ranged from 5.16% and 5.57% in 1889 to 13.27% in 1891 and 14.01% in 1897 at specific locations.
* Average reported SOM levels increased from 3.33% (1990-1999) to 4.71% (2015-2024), a 41% increase.
* Wheat yields averaged 34.6 bu/ac in 1991-1994, rising to 50.7 bu/ac in 2020-2024 (a 47% increase).
* Canola yields increased from an average of 27 bu/ac (1991-1994) to 40.4 bu/ac (2020-2024) (a 50% increase).
Executive Summary
The transition to continuous cropping and reduced tillage practices, facilitated by the commercialization of genetically modified (GM) canola, transformed crop production in the Canadian Prairies. The shift involved replacing traditional tillage and summerfallowing with herbicide-based weed control, which led to a significant reduction in tillage passes. Between 1991-1994 and 2004-2006, the use of tillage decreased by 62%, and by 2020-2024, only 1.4% of Saskatchewan crop acres included summerfallow.
These changes in land management coincided with shifts in soil organic matter (SOM) levels. Historically low SOM levels were associated with frequent tillage and summerfallowing. However, the reduction in these practices led to an overall increase in SOM levels reported by farmers between 1990-1999 and 2015-2024, with the average percentage increasing by 41%. This increase in SOM correlated with higher crop yields for wheat and canola, with reported wheat yields increasing by 47% and canola yields by 50% across the observed periods.
Higher SOM levels offer tangible benefits, including reduced soil erosion, increased moisture conservation, and a capacity to retain nutrients. These environmental advantages, alongside innovations in crop genetics and technology, contributed to the observed yield increases. The text notes that some groups spread information challenging these environmental benefits, contrasting peer-reviewed research with unverified claims regarding herbicide use and continuous cropping.
Full Take
The narrative links technological innovation—specifically GM crops and herbicide use—to systemic changes in agricultural practice, which subsequently influenced soil health and crop productivity. The critical tension lies between established, observable physical changes (reduced tillage/fallowing leading to higher SOM) and external narratives that challenge the validity of these empirical outcomes, often stemming from activist groups promoting alternative methods without peer-reviewed foundation.
The pattern observed is the displacement of traditional, resource-intensive practices by novel technological systems, which creates an emergent outcome (higher SOM, increased yields). The introduction of GM technology acts as a catalyst, setting the stage for these shifts, but the subsequent benefits are layered with external, competing interpretations regarding cause and effect. For example, when SOM increases alongside yield gains, it becomes complex to isolate whether innovation alone or the reduced physical disturbance is the primary driver, which is precisely where external framing attempts to insert simpler, non-scientific narratives.
The implication for agency is recognizing that scientific validation must operate independently of advocacy structures. When observed results (like increased yields and SOM) are presented alongside unsubstantiated claims, the focus shifts from verifying the data to negotiating the accepted reality. The manipulation tactic appears to involve exploiting the complexity of systemic change by simplifying it into an oppositional binary where established scientific findings are labeled as "false information" spread by external actors. To resist this, one must focus on the observed statistical shifts and the mechanisms described, rather than accepting external assessments of their validity wholesale.
Bridge Questions: If yield increases and SOM improvements were demonstrably decoupled from the specific mechanism of GM adoption versus general reduced tillage, how would that alter the framing of agricultural progress? What are the systemic costs of relying on unverified narratives to interpret complex environmental feedback loops? What independent methodologies are necessary to evaluate the influence of novel technologies against historical practice in similar contexts?