This series documents the work of Farm Advisor Bill Weir and previous Farm Advisors in Merced County. Records dated prior to 1976 were produced by previous Farm Advisors. The series primarily consists of trial reports and research, correspondence, meeting notes, and publications related to soil, water, cereal, barley, oats, wheat, corn, grain sorghum, sugar beets, rice, and oil crops.

The records in this subseries contain information on pest, diseases, weeds, economics and marketing, cultural practices, varieties, breeding, storage and transportation, and trial reports on the following commodities: seed production, tomatoes, cereals, barley, oats, wheat, corn, grain sorghum, sugar beets, rice, and oil crops.

This subseries contains information on soil-water-plant relations, domestic water, water, flood control, hydraulics and measurement, irrigation, irrigation districts and organization, laws and regulations, water requirements of crops, water quality, and drainage.