California’s historic drought may leave the state with the largest amount of empty farmland in recent memory as farmers face unprecedented cuts to crucial water supplies.

The size of fields intended for almonds, rice, wine grapes and other crops left unworked could be around 800,000 acres, double the size of last year and the most in at least several decades, said Josue Medellin-Azuara, an associate professor at University of California Merced.