During the 1930s, several economic and climatic conditions combined with disastrous results for South Dakota. A lack of rainfall, extremely high temperatures and inappropriate cultivation techniques produced what was known as the Dust Bowl in South Dakota and several other plains states. Fertile topsoil was blown away in massive dust storms, and several harvests were completely ruined. The experiences of the Dust Bowl, coupled with local bank foreclosures and the general economic effects of the Great Depression, resulted in many South Dakotans leaving the state. The population of South Dakota declined by more than 7% between 1930 and 1940.