Agriculture is the largest use of land in the contiguous United States. Cropland, pasture and range, and grazed forest cover 63% of the land in the lower 48 states, and cropland alone covers a fifth of it, about 390 million acres (Winters-Michaud et al. 2024, 2017 data). Most of that cropland grows just three crops: corn, soybeans and wheat made up 72% of the acres planted to principal crops in 2025 (USDA NASS 2025). We study how farming landscapes work today: what grows where, how it got that way, and what the mix of crops on the land means for the people and places that depend on it.
Landscape diversity and yields
Does a more diverse landscape grow more? Across US counties, landscapes with a richer mix of crops and land covers are associated with higher yields of major crops (Burchfield et al. 2019; Nelson & Burchfield 2021), and that positive association holds up across crops and across different ways of measuring diversity (Nelson et al. 2026). Diversity over time matters too, but rotations on most US cropland are still too simple for their yield benefits to show up at the county scale (Burchfield et al. 2024). We also map the counties that manage to be both diverse and productive, and what they have in common (Nelson & Burchfield 2023).
How today’s landscapes came to be
Today’s farming landscapes carry the legacy of a century of choices: federal farm policy, markets, infrastructure and the decisions of earlier generations of farmers (Spangler et al. 2020). Those legacies create regional path dependencies that make some places more likely to diversify than others (Spangler et al. 2022). Fieldwork in North Carolina and Idaho shows how soils, technology, markets and policy interact to shape what farmers can grow (Rissing & Burchfield 2024; Spangler et al. 2022), and interviews across four counties trace why neighbouring places moved in opposite directions (Francois et al. 2025).
What the mix of crops means
The crops on the land shape more than yields. We study what simplified landscapes mean for pollinators (Christman et al. 2022, 2024), where the fruits and vegetables in our diets are grown (Spangler et al. 2025), and how farm livelihoods and the well-being of farming communities line up with diverse and productive farming systems (Burchfield et al. 2022; Ribert et al. 2024).
Bright spots
One approach we use is bright spots analysis: mapping places whose yields are higher than soil and weather alone would predict, then asking what those places have in common (Burchfield & Schumacher 2020; Burchfield & Nelson 2021).
This work has been funded by USDA NIFA Grant 2020-67019-31157.
Publications
- Nelson, K., Bean, B., Burchfield, E. (2026). Consistent positive associations between landscape diversity and crop yields. Global Change Biology, 32(5), e70894.
- Francois, J., Nelson, K., Burchfield, E., Rissing, A. (2025). Contexts of crop selection decisions shape changing agricultural landscape diversity in the United States. Agriculture and Human Values, 42, 2631-2649.
- Spangler, K., Rissing, A., Burchfield, E., Schumacher, B., Powell, B., Siegel, K. (2025). Nutritious monocultures? Where and how fruits and vegetables are produced in the US. Global Food Security, 45, 100860.
- Burchfield, E., Crossley, M., Nelson, K. (2024). Rotational complexity across US counties is currently insufficient to observe yield gains in major crops. Environmental Research Letters, 19(4), 044024.
- Ribert, J., Nelson, K., Burchfield, E. (2024). Linking diversity–productivity conditions of farming systems with the well-being of agricultural communities. Sustainability, 16(16), 6826.
- Rissing, A., Burchfield, E. (2024). Crop diversification as landscape change: Using land systems science to understand agricultural trajectories in North Carolina. Regional Environmental Change, 24(1), 3.
- Christman, M., Spears, L., Burchfield, E., Pearse, W., Strange, J., Ramirez, R. (2024). Bumble bee responses to climate and landscapes: Investigating habitat associations and species assemblages across geographic regions in the United States of America. Global Change Biology, 30(6).
- Burchfield, E., Ferro, M., Hüttel, S., Lakes, T., Leonhardt, H., Niedermayr, A., Rissing, A., Seifert, S., Wesemeyer, M. (2024). Towards a comprehensive analysis of agricultural land systems in the EU and US: A critical view on publicly available datasets. Land Use Policy, 147, 107371.
- Nelson, K., Burchfield, E. (2023). Defining features of diverse and productive agricultural systems: An archetype analysis of U.S. agricultural counties. Frontiers in Sustainable Food Systems, 7, 1081079.
- Rissing, A., Burchfield, E., Spangler, K., Schumacher, B. (2023). Implications of US agricultural data practice for sustainable food systems research. Nature Food, 4, 213-217.
- Burchfield, E., Schumacher, B., Spangler, K., Rissing, A. (2022). The state of US farm operator livelihoods. Frontiers in Sustainable Food Systems.
- Christman, M., Spears, L., Strange, J., Pearse, W., Burchfield, E., Ramirez, R. (2022). Land cover and climate drive shifts in Bombus assemblage composition. Agriculture, Ecosystems and Environment, 339, 108113.
- Spangler, K., Schumacher, B., Bean, B., Burchfield, E. (2022). Path dependencies in US agriculture: Regional factors of diversification. Agriculture, Ecosystems and Environment, 333, 107957.
- Spangler, K., Burchfield, E., Radel, C., Jackson-Smith, D., Johnson, R. (2022). Crop diversification in Idaho’s Magic Valley: the present and the imaginary. Agronomy for Sustainable Development, 42, 99.
- Nelson, K., Burchfield, E. (2021). Landscape complexity and US crop production. Nature Food. https://doi.org/10.1038/s43016-021-00281-1
- Burchfield, E., Nelson, K. (2021). Agricultural yield geographies in the United States. Environmental Research Letters. https://doi.org/10.1088/1748-9326/abe88d
- Burchfield, E., Schumacher, B. (2020). Bright spots in US corn production. Environmental Research Letters, 15(10).
- Spangler, K., Burchfield, E., Schumacher, B. (2020). Past and current dynamics of US agricultural land use and policy. Frontiers in Sustainable Food Systems, 4, 98.
- Burchfield, E., Nelson, K., Spangler, K. (2019). The impact of agricultural diversification on U.S. crop production. Agriculture, Ecosystems & Environment, 285, 106615. Preprint available here.