In the 1930s, the southern Great Plains of the United States some of the worst environmental disasters in the nation's history. Huge clouds of dust, sometimes thousands of meters high, swept across the , turning day into night. On April 14, 1935, a day later known as "Black Sunday," one storm carried so much that people caught outside could hardly see their own hands. The became known as the Dust Bowl, and the disaster forced hundreds of thousands of people to their homes in search of work .
Although a long was the cause of the storms, the roots of the disaster went back several decades. In the late nineteenth and early twentieth centuries, the government encouraged settlers to move to the plains by offering them land at little or no cost. The had originally been covered with deep-rooted grasses that held the in place, even during dry periods. When wheat prices rose sharply during World War I, farmers began plowing up millions of hectares of these grasslands. New machines such as tractors made it possible to clear land far more quickly than ever before.
For a time, the seemed successful, as rainfall was unusually high and harvests were large. After the economy collapsed in 1929, however, wheat prices fell dramatically. To make up for their losses, many farmers plowed even more land and planted more wheat, which only lowered prices further. Then, in the early 1930s, the rain stopped. Without the grasses to protect it, the dry, exposed was easily picked up by the strong winds that are common on the plains.
The government responded with a of programs. In 1935, it established the Service, led by a scientist named Hugh Hammond Bennett, who had spent years warning about the dangers of erosion. The agency paid farmers to new methods, such as plowing along the natural curves of the land and rotating crops so that the would not be . In addition, more than 200 million trees were planted in long lines across the plains to slow the wind. By the end of the , the amount of being blown away had been greatly reduced.
Today, historians the Dust Bowl as a warning about what can happen when people ignore the limits of the natural environment. Some scientists point out that the faces a similar risk today. Many farms on the plains now depend on water pumped from deep , and in some areas this water is being used much faster than it can be replaced. If it runs out, they warn, large areas of farmland could once again be left dry and unprotected.
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Q1p1_long_b
What was one reason farmers began plowing large areas of grassland?
Q2p1_long_b
Why did conditions on the plains become worse after 1929?
