"A new study by Christopher Wright and Michael Wimberly of South Dakota State University finds that U.S. farmers converted more than 1.3 million acres of grassland into corn and soybean fields between 2006 and 2011," writes Plumer. As up to five percent of grasslands in some states are converted to cropland each year, the northern Plains are confronting unexpected problems.
For example, notes Plumer, the loss of pasture could have big environmental impacts. "Studies have found that grasslands hold carbon in their soil better than cropland does."
"There’s a wildlife angle, too: The Prairie Pothole Region, traversing Minnesota and the Dakotas, is one of the continent’s key breeding grounds for ducks and other ground-nesting birds. Tall grasses in the area help sustain a number of species and shield birds from predators. But corn fields are now encroaching on the habitat, and bird populations are dropping."