Drought threatens the stability of the United States’ for age system, yet the magnitude and spatial heterogeneity of its impacts on alfalfa remain poorly quantified. We construct a state-year panel for 2005–2025 that links geospatially matched SPEI-03 measures over alfalfa land with state-level data on yield, irrigation, and export value. Spatial diagnostics show weak joint spatial structure between drought and export value, and both variables are individually spatially correlated. Combining with panel fixed-effects
models and generalized additive models, we find that drought significantly reduce alfalfa yield, with the strongest vulnerabilities concentrated in irrigation-dependent western states. By contrast, drought variation has a weaker reduced-form association with export value once persistent geography, prices, and state heterogeneity are taken into account. These findings suggest that drought affects alfalfa trade primarily through production capacity, while export performance is partially buffered by logistics, market access, and water-management institutions. The results underscore the need for region-specific adaptation strategies, including irrigation-efficiency and acreage-adjustment policies in the West and feed-risk management tools in the Midwest.
