During the 1930s a combination of severe drought and the ploughing of fragile grassland for wheat turned the southern Great Plains into a zone of recurring dust storms. Topsoil stripped from millions of hectares buried farms and darkened skies as far as eastern cities. Hundreds of thousands of people abandoned the land, many migrating west toward California in search of work during the Depression. The crisis prompted federal soil-conservation programmes and resettlement schemes.
It linked land mismanagement to mass rural-to-urban migration and helped establish a federal role in land use, conservation and regional planning.
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