Resumen
During the 1850s, land in U.S. farms increased by more than a third?100 million acres?and almost 50 million acres, an area almost equal to that of the states of Indiana and Ohio combined, were converted from their raw, natural state into productive farmland. The time and expense of transforming this land into a productive agricultural resource represented a significant fraction of domestic capital formation at the time and was an important contributor to American economic growth. Even more impressive, however, was the fact that almost half of these total net additions to cropland occurred in just seven Midwestern states which comprised somewhat less than one-eighth of the land area of the country at that time. Using a new GIS-based transportation database linked to county-level census data, we estimate that at least a quarter (and possibly two-thirds or more) of this increase in cultivable land can be linked directly to the coming of the railroad to the Midwest. Farmers responded to the shrinking transportation wedge which raised agricultural revenue productivity by rapidly expanding the area under cultivation and these changes, in turn, drove rising farm and land values.