High Quality Content by WIKIPEDIA articles! Wheatland is a city in Yuba County, California, United States. The population was 3,456 at the 2010 census, up from 2,275 at the 2000 census. Wheatland is located 12.5 miles (20 km) southeast of Marysville. It is most commonly known to Northern Californians as the home of Sleep Train Amphitheatre, an open-air 18,500 seat venue for music and other performing artists.