Jim Clare grew up in Bakersfield California, attended Bakersfield High School and Bakersfield Jr. College before completing his Bachelor of Science at the University of California at Davis. In 1974 Jim went to work for Rain for Rent at their Woodland California office as an outside sales person, and in 1978 Rain for Rent moved Jim to Stockton, California to establish a new agricultural branch. In 1985 Jim started Golden State Irrigation Services in Stockton, and by 2003 had grown Golden State to five offices, providing irrigation services world wide. Jim was forced out of Golden State in 2003, when the partners could not reconcile differences in regard to the direction of the company.

He established Pacific SouthWest Irrigation with his long time friend and associate Gary Simas, in the fall of 2003.

Jim Clare has probably supervised the installation of more agricultural irrigation systems of different types than anyone in the West. In 1978 he installed the first commercially successful row crop drip irrigation systems in the Central Valley, he was the first to rent sand media filtration for row crop drip systems, and developed methods and combinations of equipment for seed germination with overhead portable sprinklers, in 1979 he began installing drip system in vineyards and was a leader in this technology by 1988 when drip irrigation became state of the art for vineyards, in the 80s he began working with Rain Bird and ultimately Nelson on sprinklers and spacing which more closely matched the infiltration of soils and provided better coverage. He is a recognized expert in turf grass sod irrigation.

In 1988 Jim saw a need for an alternative to aluminum pipe for row crop irrigation and portable pipe lines. His idea was to use plastic pipe. With CertainTeed Corp. and Nelson Irrigation Corp, he developed and introduced Yellowmine, Certa Lok, Certa Set, Golden 2000 System for agriculture. He is the inventor of these systems and has two patents. He assisted Nelson with the introduction of the rotator sprinkler family and it was his persistence which led to the Nelson windfighter sprinkler and the pressure regulating check valve, widely used in row crops today.

Jim is a former director of The Irrigation Association and Irrigation Research and Training Center at Cal Poly, he was the founding director of the California Irrigation Dealers Association which is now the California Irrigation Association. As a director of the Irrigation Association he pushed for certification of Irrigation Designers and Contractor Licenses for Irrigation Dealers. He was one of the first dealer owners to become certified in both drip and sprinkler design. Jim is also a graduate of the California Ag Leadership Program Fellowship and is a former Director of the San Joaquin County Ag Hall of Fame and Stockton Farm Show. Jim lives with his wife Ellen in Escalon, California, has four children and has been a women's volleyball coach for nearly twenty years.