Every summer, wine scientist Andrew Walker embarks on one or two road trips in search of wild grapes. Armed with an eagle eye, a team of graduate students, and a rental car—the wheels on one side rolling along the asphalt and the wheels on the other rumbling through the adjacent gravel—Walker estimates that he drives between 400 and 500 miles per day in search of native grape varieties, which conveniently thrive along the edges of roads. When he comes across a wild grape, he uproots the plant, places it in a Ziploc bag, and stores it on ice.
For obvious reasons, uprooted plants don’t last long, so these foraging trips never last more than a few days. Walker then brings the wild varieties back to his lab at the University of California, Davis, where he’s a professor of viticulture and enology (fancy terms for “wine-growing” and “the study of wine,” respectively). The plants will go on to play an integral role in his research, breeding grapes to withstand one of today’s most challenging environmental issues: salty soil.
The gradual, upward creep of soil salinity is a quiet phenomenon—one that doesn’t get as much attention as, say, historic levels of flooding or incurable plant diseases. The factors that drive salinization, as it is officially known, are manifold. The use of certain high-salt fertilizers can increase salinity; as can saltwater intrusion—a problem that occurs in coastal regions where seawater from the ocean seeps into groundwater reserves.