The map is part of a study published in Proceedings of the National Academy of Sciences, which found that bee populations declined by 23 percent from 2008 to 2013, and 39 percent of U.S. croplands that depend on pollinators "face a threatening mismatch between rising demand for pollination and a falling supply of wild bees," Brown writes. The study "indicates that farmers will face increasing costs—and that the problem may even destabilize the nation’s crop production." (University of Vermont map)
The study "identifies 139 counties in key agricultural regions of California, the Pacific Northwest, the upper Midwest and Great Plains, west Texas, and the southern Mississippi River valley that have the most worrisome mismatch between falling wild bee supply and rising crop pollination demand," Brown writes. "These counties tend to be places that grow specialty crops—like almonds, blueberries and apples—that are highly dependent on pollinators. Or they are counties that grow less dependent crops—like soybeans, canola and cotton—in very large quantities."