The drought and erosion of the area that came to be called the Dust Bowl, affected 100,000,000 acres from the panhandles of Texas and Oklahoma through New Mexico, Colorado, and Kansas up to Canada, all in the lee of the Rocky Mountains.

The Dust Bowl developed in the 1930s. There were severe dust storms that greatly damaged the farming of the U.S. and Canadian prairies. It was brought on by the farmers not being familiar with the area they had moved to, or the ways of coping with a pattern of rainfall that gave a few wet years followed by several drought years.

The drought came in three waves, 1934, 1936, and 1939–40, with some regions experiencing drought conditions for as many as eight years in a row.

Farmers did not understand why the prairie grasses survived, and what their deep roots were for - they were to find water during times of drought. Their tall stems also meant that strong prairie winds never reached the deep soils in which they grew. But the farmers ploughed up the land and removed the grasses, and instead planted shallow-rooted wheat, then harvested it and left the ground bare.

During the drought of the 1930s, the exposed soil turned to dust, which the prevailing winds blew away in huge clouds that sometimes blackened the sky. They were called "black blizzards" and "black rollers". The video below shows you much more.

Tens of thousands of families had to abandon their farms. These migrants were called "Okies" because so many of them came from Oklahoma. Many migrated to California.

Author John Steinbeck wrote The Grapes of Wrath in 1939, one of the world's most famous books. It told the story of migrant workers and the Dust Bowl.