Having grown up working in his parents' vineyard, Peter became an internationally renowned viticulture scientist, and was widely considered the world's leading authority on grapevine nutrition and fertility management. He received his BS in Viticulture from California State University, Fresno, in 1956, followed by an MS in Viticulture from the University of California, Davis, in 1959.
Following his graduation from UC Davis, he joined UC Cooperative Extension as a farm advisor in Fresno County, where he spent 23 years working with the local grape industries. In 1984 he advanced to the position of viticulture specialist in the Department of Viticulture and Enology, stationed at the UC Kearney Agricultural Research and Extension Center in Parlier, where he retired in 1999. Working closely with colleagues in academia and industry, he conducted practical research on a broad range of topics. Much of this work had immediate and long-lasting impact. For example, the mineral nutrition and diagnostic and fertilizer recommendations for California vineyards are largely based on his research and extension activities. He authored or co-authored over 250 technical papers and research articles during his career, including several seminal publications on grapevine nutrition and the statewide UC production manuals on raisin production, wine grape varieties and grape pest and disease management. He received the Best Research Paper Award from the American Journal of Enology and Viticulture in 1986 and 1990, and also served as the President of the American Society for Enology and Viticulture in 1991-1992. In 1997 he was presented the James H. Meyer Outstanding Career Achievement Award from UC Davis, and in 2004 he was given the Merit Award of the American Society for Enology and Viticulture. The latter is the highest honor given to a grape research scientist in the U.S. In recognition of his outstanding contributions to the California raisin industry, the newly developed raisin grape variety "Selma Pete" was named in his honor in 2002.
In addition to his outstanding research contributions, Peter was a gifted, thoughtful and generous extension educator and mentor to young scientists. He presented hundreds of technical talks to Central Valley grape growers, and also trained many UC Farm Advisors during his career. His impact extended far beyond California, and he visited many different countries on sabbatical leaves and technical trips, including Australia, New Zealand, South Africa, Greece, Italy, Chile, Mexico, Japan, Canada, Uzbekistan and 11 States in the USA.
Peter is remembered by his family, friends and colleagues, and by grape growers throughout the Central Valley and beyond, for his unfailing readiness to help and serve, for his humility, and for his good nature and sense of humor. He was a faithful member of the St. Peter the Apostle Serbian Orthodox Church in Fresno, where he was actively involved in the landscaping and maintenance of the church property. For many years he farmed the family vineyards that he inherited along with his sister. His interests included traveling, writing, cooking (including gourmet meals), gardening, boating, fishing and scuba diving. Family closeness was very important to him, and he frequently arranged family get-togethers and vacations in various parts of the state and in countries throughout the world. After a battle with cancer, he ended his earthly life with his characteristic positive attitude, saying that he could not have asked for anything more in life, that he had no complaints, and that he was deeply thankful to God for everything. In the meaningful time leading up to his passing, he received an outpouring of love from his family and from many others whose lives he had touched, and to whom he had always been a selfless servant.
Peter is preceded by John L. Christensen and Florence M. (née Andersen) Christensen.
He is survived by his wife, Eleanor; his sons, John (Fr. Damascene), Robert and Scott; his daughters-in-law, Bonnie and Lorraine; his grandchildren, Jonathan, Emily and Melina; his sister, Jane Hildebrand; and his godparents, Ron and Radmila Tarailo.
Contributions in Peter's name may be sent to the St. Herman of Alaska Monastery, P.O. Box 70, Platina, Ca, 96076.