Progress in wheat farm yield improvement has largely stagnated across the U.S. Pacific Northwest

Authors: Adams, Curtis; GRAEBNER, RYAN - Oregon State University; Durfee, Nicole

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/24/2026
Publication Date: 7/9/2026
Citation: Adams, C.B., Graebner, R., Durfee, N.M. 2026. Progress in wheat farm yield improvement has largely stagnated across the U.S. Pacific Northwest. Scientific Reports. 16. Article 31542. https://doi.org/10.1038/s41598-026-60000-3.
DOI: https://doi.org/10.1038/s41598-026-60000-3

Interpretive Summary: Stagnation in wheat yield improvement has been documented in some global production hubs. This is a serious concern because increased food production is needed to meet the demands of the projected future population. There are vague indications that yields may be stagnating in the U.S. Pacific Northwest, but no strong investigation has been conducted. Our objective was to provide this analysis. We found that historically there were linear increases in yields over time across all USDA agricultural districts of the Pacific Northwest states. Incremental shifts toward irrigation in some districts drove the highest rates of historic yield increase. But yields largely stagnated between the early 1980s and mid-1990s. We found that plant breeding efforts over the last 25 years have largely prevented yield erosion, but have not contributed to yield gains like they did prior to the mid-1990s. These findings present a sort of paradigm shift for regional farmers. Farmers cannot rely on sustained improvement of yields to be competitive in global wheat markets or to improve farm revenue. In the absence of further innovations to improve yields, farmers can best accomplish these things by improving production efficiency. Gaining rigorous understanding of factors contributing to yield stagnation is critical to reversing the trend, followed by agricultural innovations, likely in multiple areas.

Technical Abstract: Yield stagnation, which has occurred in some global wheat production hubs, is a serious barrier to meeting future food demands. Yield trends across the U.S. Pacific Northwest, where 8.2 million Mg of wheat was produced in 2025, are mostly unknown. Using publicly available data (USDA farm surveys and university-led wheat variety trials), the objective of this research was to evaluate winter wheat yield trends across Oregon, Washington, and Idaho since the early 1970s. Survey analysis showed that historic rates of yield increase among agricultural districts ranged from 0.018 to 0.195 Mg ha-1 year-1, with incremental shifts toward irrigation in select districts driving the highest rates. But yields largely stagnated between the early 1980s and mid-1990s. Analysis of top-yielding varieties in 163 variety trials conducted since 2000 showed a slight yield decrease in lower-yielding systems (-0.00309 Mg ha-1 per year of variety release or -0.093% p.a.) and a non-significant change of -0.013% p.a. in higher-yielding systems. Thus, only "maintenance breeding" rather than actual yield increase is being accomplished through current breeding efforts. These findings have broad implications for regional farmers and multidisciplinary researchers who support them. Gaining rigorous understanding of factors contributing to yield stagnation is critical to reversing the trend.