American consumers' demand for chemical-free and locally produced food has caused a surge in the number of organic operations across the county, new figures show.

The U.S. Department of Agriculture reported Monday that the number of certified organic producers jumped by almost 12 percent from 2014 to 2015 -- the highest rate increase since 2008.

"A powerful local and regional food movement is growing inside the United States," Agriculture Secretary Tom Vilsack wrote in a lengthy post Monday on Medium, "a movement that directly connects consumers with how, where and by whom their food is grown."

Vilsack called organic food "one of the fasting growing segments of American agriculture."