With Paul Adrian (a U.S. Department of Agriculture agricultural engineer stationed at UC Davis), Bob initiated studies of mechanized harvesting of tree fruits and nuts. Although some mechanical harvesting had been done prior to this time, Bob identified the parameters that influence tree response to vibration and provided a basis for the rational design of shakers. He then studied the response of fruit to impact and determined the best design for collecting surfaces to minimize bruising. This work led to several patents and advanced mechanization in California, nationally, and around the world. Bob also collaborated with several other individuals at UC Davis, most notably Dr. Larry Claypool, a postharvest physiologist in the Department of Pomology, and James Mehlschau, a development engineer in the Department of Agricultural Engineering.
Bob’s accomplishments included the development of the inertial tree shaker, the integrated shake-catch harvester, shaker clamps that minimize damage to tree bark, and criteria for the design of fruit-catching surfaces to minimize the bruising of fruit during harvesting and handling. Most tree-fruit harvesters today are designed based on principles developed by Bob, and most growers who produce fruit to be mechanically harvested follow the guidelines for tree shape and pruning that were identified during his research. In 1983, Bob co-authored, with Michael O’Brien, UC Davis, and Burton Cargill, Michigan State University, Principles and Practices for Harvesting Fruits and Vegetables (AVI Publishing Company, 1983).
Bob was known as much for his leadership and ability to foresee the future as for his creativity, problem solving, and productivity. In 1977, he left the university and put all of those capabilities to good use in pursuing his interest in forest engineering research with the Weyerhaeuser Company. He began as manager of silvicultural research and development (R&D) and advanced through multiple positions to manager of diversified technology R&D. In the latter role, he was responsible for all research related to silviculture, agriculture, and aquaculture. Bob’s team at Weyerhaeuser developed technology for reforestation and methods of raising and releasing juvenile salmon for ocean ranching.