Sierra League was an Independent League that was based in California
1928 La Grange, Livingston, Modesto, Newman, Patterson, Waterford
1929 Atwater, Ceres, Keyes, Livingston, RIverbank, Waterford
1930 Atwater, Hughson, Livingston, Modesto, RIverbank , Waterford
1931 Atwater, Livingston, Modesto, Turlock, Waterford
1932 Merced, Modesto, Ripon, Turlock, Waterford'
1933 to 1940 Not Sure if this League Played
1941 Hughson, Modesto, Riverbank, Shannon