Margaret Barbree Rosenberg was the wife of Walter Rosenberg, whose family had been the owner of Rancho San Bernardo since 1871. The rancho was one of the last remaining intact Mexican California land grants and it had been owned entirely by the family and descendants of Meyer Brandenstein since 1898. Margaret B. Rosenberg was married to Walter Rosenberg and spent a majority of her early life living on a cattle ranch during the "bare handed" days. She recounts the history of the Meyer Brandenstein and the Joseph Rosenberg families as well as the Barbree and Quinn families. She held particular interest in John Steinbeck and the Salinas Valley and the people, activities, structures and streets of San Ardo. In this interview, Rosenberg discusses the history of Monterey County Mexican California land grants, the Rancho San Bernardino beginning in 1871, water supply, oil and cattle, her school years, Walter Rosenberg, her public service and community affairs, and the Rosenberg family and their relatives. Included is a 1972 Report on the San Ardo Oil Field. This interview is part of a group of interviews documenting the Society of California Pioneers.