The tractors rolled on, the grass yanked up, a million acres a year, turned and pulverized; in just five years, 1925 to 1930, another 5.2 million acres of native sod went under the plow in the southern plains—an area the size of two Yellowstone National Parks. This was in addition to nearly twenty million acres of prairie that had already been turned. Only four small farms existed in Dallam County, Texas, in 1901, covering barely a thousand acres; by 1930, a third of the county was in cultivation.
