The University of California, Riverside (UCR or UC Riverside), is a public research university and one of the 10 general campuses of the University of California system. The main campus sits on 1,900 acres (769 ha) in a suburban district of Riverside, California, United States, with a branch campus of 20 acres (8 ha) in Palm Desert. Founded in 1907 as the UC Citrus Experiment Station, Riverside pioneered research in biological pest control and the use of growth regulators responsible for extending the citrus growing season in California from four to nine months.