I think this is Q. turbinella by the size and shape of the leaves
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California
Anza-Borrego Desert State Park, Borrego Springs, San Diego County, California