Dr. Whitfield: Today we're looking at the Dust Bowl, which hit the southern Great Plains, including the Texas Panhandle, during the 1930s.

Dr. Whitfield: In the years before, farmers had plowed up millions of acres of native grassland to plant wheat. Those grasses had deep roots that held the soil in place, even during dry years. When a long drought arrived in the early 1930s, the crops died, and there was nothing left to hold the soil down.

Dr. Whitfield: The wind did the rest. Huge dust storms carried topsoil for hundreds of miles. The worst day, April 14, 1935, became known as Black Sunday, when a wall of dust turned the afternoon dark.

Dr. Whitfield: So the Dust Bowl was not only a natural disaster. The drought was natural, but the damage was much worse because of how the land had been used. That's why the federal government created the Soil Conservation Service in 1935, to teach farmers methods like planting rows of trees as windbreaks and plowing along the shape of the land. Keep that idea in mind: human choices can turn a hard situation into a disaster.