Son of French immigrants, Clem Pelissier was born in San Francisco in 1914. He grew up on a diversified farm - dairy, poultry, fruit, forage crops - near Santa Rosa. He attended Santa Rosa High School, achieved state and national recognition in 4-H and FFA, and was a member of award winning judging teams. In 1932 he enrolled at UC Davis, majoring in Animal Husbandry. He was elected to Alpha Zeta and held several student body offices. During his senior year he was Chairman of Picnic Day and sat on the Welfare Council. Upon graduation in 1936, he joined the University of California Agricultural Extension Service.
During World War II, Clem served with the US Navy. He met US Army nurse, Jeanne Moore and they were married in Honolulu in 1944. In 1946 the couple moved to Tulare where Clem resumed his Extension Service work.
In 1949, he was transferred to UC Davis as Extension Dairyman, a position he held until his retirement. Clem and Jeanne spent a sabatical leave at Cornell, where he earned a Master's degree in 1952. Later they were to spend leaves in Lebanon (1963-64) and Australia and New Zealand (1972-73). In addition, shorter international assignments took them to Peru, Iran, Algeria, and Qatar.
During his career, Clem maintained his dairy cattle judging credentials, officiating at 5 to 10 shows a year. He supervised the Dairy Herd Improvement (DHI) program from 1950 to 1968, during which time producer participation in the program almost doubled. He published over 250 articles in popular journals and 52 articles in scientific journals, bulletins, or circulars. He served for many years on the California Department of Food and Agriculture Bureau of Animal Health and Artificial Insemination Advisory Committees. A 20-year member of the Commonwealth Club of California, he served on their International Affairs and Agricultural Committies. He was also a member of several American Dairy Science Association committees.
On his retirement in 1982, Clem's contributions to the University and the State were recognized by a citation from the California Legislature.