The Underhill Collection consists of scattered correspondence and minutes of the Stockton Potato Day Records Committee (1924, 1925); minutes of the San Joaquin County Farm Bureau Tomato Section meetings (1946-1947); copies of the Tomato Growers Association Bulletin (1946-1958); a brief history of the establishment of the Cooperative Marketing Council in San Joaquin County (1946-1947); an agenda and related items pertaining to the Cooperative Marketing Council's Cooperative Directors Conference (1956); and the "Tomato Issue" of Tideways magazine (1967).

The San Joaquin River Delta peat lands were a major producer of potatoes from 1900 until about 1925. Two of the most prominent of the Delta potato growers were Chin Lung and George Shima. The latter, the first Japanese American millionaire and head of the Japanese Association of America, was known as the "Potato King." San Joaquin County potatoes were successful in eastern markets because they could be harvested almost any time of year. After 1925, the Delta potato hegemony collapsed under pressure from competition in southern California, Oregon, and Idaho. Due to the popularity of potatoes, local boosters conceived the idea of a "Potato Day" (1924). This event was celebrated at the Kroyer Plant on Cherokee Lane with a carnival, displays, formal ceremonies, and a dance. Starting in the 1930s, tomatoes became a far more important San Joaquin County crop. With irrigation, tomatoes could be grown in many county locations and their cultivation was stimulated by successful food processors such as the Flotill Corporation of Stockton, which specialized in pomodoro tomato canning, and the Heinz Company of Tracy, premier ketchup manufacturers. John P. Underhill was assistant farm advisor (1946-1955) and director (1956-1975) of the University of California Agricultural Extension Service in San Joaquin County. He collected these materials in the course of his work with the potato and tomato growers of San Joaquin County.

.5 linear feet

The library can only claim physical ownership of the collection. Users are responsible for satisfying any claimants of literary property.

Collection is open for research by appointment.