Ensuring the survival of agriculture under an increasingly erratic climate is approaching a crisis in the sere and sweltering Western and Southwestern United States, an area that supplies much of our beef and dairy, alfalfa, tree nuts and produce. Contending with too little water to support their plants and animals, farmers have tilled under crops, pulled out trees, fallowed fields and sold off herds. … In the last five years, researchers have begun to puzzle out how brackish water, pulled from underground aquifers, might be de-salted cheaply enough to offer farmers another water resilience tool. … Desalination renders salty water less so. … Inland desalination happens away from coasts, with aquifer waters that are brackish — containing between 1,000 and 10,000 milligrams of salt per liter, versus around 35,000 milligrams per liter for seawater. Texas has more than three dozen centralized brackish groundwater desalination plants, California more than 20. Such technology has long been considered too costly for farming. Some experts still think it’s a pipe dream.