Continental Interior or Agricultural Heartland

Center-pivot irrigation waters the aridisols (dry soils) of this region. The delicate Ogallala Aquifer irrigates these soils and their associated crops. An aquifer is an underground reservoir that may be tapped for irrigation, drinking water, or other terrestrial purposes. This giant aquifer was tapped with wells beginning in the late 1930s. The aquifer is believed to have held, at maximum capacity, enough water to cover the entire continental United States in one and one-half feet of water. Measurements have determined that in the time between 1940 and 1980 the aquifer depth decreased an average of 10 feet per year. Recharge is much slower than the rate of use. The Ogallala was made slowly over millions of years, but thirsty farmers are endangering the resource and are on pace to deplete it within the next fifty years. This is a terrible thought knowing how dependent we, and the world, are on the food products of the Interior that derive their sustenance from this water.

This region stretches from the Mississippi Valley to the base of the Rocky Mountains. It includes the Corn Belt, focused in Iowa and Illinois, and the Wheat Belt (spring wheat in the north, winter wheat in the south).