Workers sort through key limes at a packaging house in Apatzingan, Michoacan. More than 90 percent of limes imported into the U.S. come from Mexico. Carrie Kahn/NPR hide caption

itoggle caption Carrie Kahn/NPR

Backers of the new Open Source Seed Initiative will pass out 29 new varieties of 14 different crops, including broccoli, carrots and kale, on Thursday. J. Scott Applewhite/AP hide caption

itoggle caption J. Scott Applewhite/AP

Dairy cows feed through a fence at an Idaho farm, in this 2009 file photo. Idaho's Gov. C.L. "Butch" Otter enacted a bill Friday that criminalizes the act of secretly filming animal abuse at farms. Charlie Litchfield/AP hide caption

itoggle caption Charlie Litchfield/AP

Benny Bunting, a farm advocate for Rural Advancement Foundation International-USA, in front of one of his old chicken houses in Oak City, N.C. Dan Charles/NPR hide caption

itoggle caption Dan Charles/NPR

Economists say small-business owners — especially farmers dealing in high volume and low profit margins — are more likely to accept a volatile currency like Bitcoin than bigger businesses. Allen Sheffield/Flickr hide caption

itoggle caption Allen Sheffield/Flickr

At Happy Boy Farms near Santa Cruz, Calif., Early Girl tomatoes are grown using dry-farming methods. The tomatoes have become increasingly popular with chefs and wholesalers. Courtesy Jen Lynne/Happy Boy Farms hide caption

itoggle caption Courtesy Jen Lynne/Happy Boy Farms

An irrigation pivot waters a corn field in Nebraska. Many farmers in Nebraska and Kansas rely on irrigation to water their corn fields. But the underground aquifer they draw from will run dry. Nati Harnik/AP hide caption

itoggle caption Nati Harnik/AP

Scientists with the U.S. Geological Survey sample water in Goodwater Creek, Mo., for pesticides and other chemicals that may have run off from the surrounding land. Abbie Fentress Swanson/Harvest Public Media hide caption

itoggle caption Abbie Fentress Swanson/Harvest Public Media

Prehistoric "pantries": This illustration is based on archaeological findings in Jordan of structures built to store extra grain some 11,000-12,000 years ago. Illustration by E. Carlson/Courtesy of Dr. Ian Kuijt/University of Notre Dame hide caption

itoggle caption Illustration by E. Carlson/Courtesy of Dr. Ian Kuijt/University of Notre Dame

Left to their own devices, many seedless grapes would be puny and soft. But these Thompson seedless got pleasingly plump after a little girdling and hormone treatment. Daniel M.N. Turner/NPR hide caption

itoggle caption Daniel M.N. Turner/NPR

Valley Malt, in Hadley, Mass., works with 25 farmers growing six different types of grain in the Northeast. Courtesy of Valley Malt hide caption

itoggle caption Courtesy of Valley Malt