Source: adapted from Stutz, R. and A. de Souza (1998) The World Economy: Resources, Location, Trade and Development, Third Edition, Toronto: Prentice Hall, p. 268.
Significant improvements in transport technology took place since Von Thunen designed his agricultural land-use model in the 19th century. For instance, with rail systems and grain elevators, it became much more cost-effective to transport agricultural commodities over long distances. Refrigeration allowed perishable products to be moved cost-effectively over long distances as well. Since most of the American agricultural landscape was established in the late 19th and early 20th century, agricultural land use was much less constrained by transport costs than its European and Asian counterparts. Large scale agricultural regions thus emerged where agricultural land use was influenced by distance from major markets and by local geographical conditions. As such, it is possible to apply Von Thunen’s assumption to agricultural land use over the continental United States.
- Figure A represents what the agricultural land use would be if the most basic assumptions were applied, namely the market located at New York (or BostWash), crops being ranked by comparative rent-paying abilities, and considering ubiquitous geographical characteristics. Although this representation has some level of concordance with reality, it inaccurately portrays agricultural land use in the United States.
- Figure B includes one supplementary assumption that considers climate variations, where the north is colder than the south. This constraint has a significant impact on agricultural land use as even if for a location a crop would have a higher rent-paying ability, another crop would be grown because climatic conditions forbid it. The resulting agricultural land use has a much higher level of correspondence with reality.