By Elizabeth Leake, InSTePP Communication Specialist, University of Minnesota 

In a recent study published in the March 2015 edition of The Journal of Economic History, Jason Beddow and Philip Pardey (University of Minnesota, InSTePP) challenge some long-standing notions about the past and future evolution of crop production by taking explicit account of agriculture’s geographically-shifting footprint.

When analyzing crop yields, economists have long emphasized commercially-marketed and managed inputs, such as fertilizer, machinery, irrigation, and crop genetics, without giving as much consideration to spatially-explicit policy, biological and environmental conditions such as soil type, sunlight, rainfall, temperature, pests, and diseases. By so doing, they risk misattributing sources of growth (to inputs) and overestimating the effects of technological advances and climate change.

Beddow and Pardey’s new insight was that common economic indexes could be adapted to assess the output consequences of shifting the location of crop production. They applied these spatial indexes to analyze US corn production data for 1879 to 2007, a 128 year period during which there was a notable north-westerly movement in where corn was produced—the average corn plant in 2007 was grown over 400 kilometers northwest of its 1879 ancestor. Strikingly, some 16-21 percent of the increased corn output over the period is attributable to that movement, and, implicitly, the corresponding changes in biology, technology, weather, and economics faced by corn farmers.

InSTePP researchers are now investigating whether similar patterns of movement are evident for other crops and regions. Preliminary results reported by Beddow and Pardey find that more recent movements in the location of sub-Saharan African corn production may have had the opposite effect: decreasing crop output. Notwithstanding, the study raises prospects for future changes in where crops are grown to increase global crop production and mitigate impacts of global climate change.