Spatial and Temporal Distribution of Locations of Round Barns in the United States

Inventories of round barns have been published for many of the Midwestern states, where such barns are most prevalent. This study adopts a broader perspective and considers distribution of round barns in the entire continental United States to address questions such as why the vast majority of these barns are located in the Midwest; are there centers of influence detectable in the spatial and temporal distribution; and why did the period of greatest building activity last only two decades at the start of the twentieth century? Round barn locations are concentrated in regions were glacial sediments provide fertile soil for farming activities, not only in the Midwest but also in the north-eastern states of Pennsylvania, New York, and Vermont. Surprisingly, perhaps, is the lack of any influence of local topography on the locations of round barns. There is no direct correlation between the number of farms in a particular county and the number of round barns in that county. Nor is there any clear sign of spatio-temporal clustering associated with external influences such as agricultural research stations. As far as can be determined from the available data, the period of building frenzy was common to all states above the Mason-Dixon line and east of the Continental Divide, lagging the expansion of farms during the last two decades of the nineteenth century. This suggests that the round barn experiment that occured was not entirely successful because of inherent limitations in the design and building of circular structures, and not so much because of external factors that changed, such as loss of support from agricultural research stations or farming periodicals. This study uses diffusion-based marketing models to show how the bell-shaped curve of number of barns built over time agrees with the forecasted rate of adaptation of an innovation or new durable goods product.