George Earl Templeton II was born in Little Rock on June 27, 1931, the son of George and Gladys Jones Templeton. He attended the University of Arkansas, where he received a B.S.A. in agriculture in 1953 and a M.S. in Plant Pathology in 1954. After completing two years of military service, he resumed his studies at the University of Wisconsin, where he completed a Ph.D. in Plant Pathology in 1958. He married Bobbie Nell Templeton; they had three sons and a daughter.

Upon his graduation from UW, he returned to the University of Arkansas as an Assistant Professor of Plant Pathology. In 1967 he attained the rank of professor, and was promoted to the rank of University Professor in 1985 and Distinguished Professor in 1991. As part of his duties he trained several graduate students in plant pathology. He conducted research in the fields of rice diseases and fungal toxins, with a special interest in the biological control of weeds with fungal plant pathogens. His achievements included developing several varieties of improved disease-resistant rice, as well as one wheat variety. With the assistance of colleagues, he isolated and identified tentoxin, found in plant pathogenic Alternaria tenuis, and also the spore germination self-inhibitor gloeosporone from Colletotrichum gloeosporioides. From his discoveries he developed the first commercial mycoherbicide, Collego, for use in rice and soybeans. In the course of his career he had over 130 publications dealing with his research. He also played a key role in the establishment of the University of Arkansas' Alternative Pest Control Center in 1989.

Templeton's expertise earned him both national and international recognition, and he served as a consultant on numerous projects. A member of the American Phytopathological Society, he established its Biological Control Committee. He also established the Southern Regional Project S-136 on Biological Control of Weeds with fungi. He further served as a member of the Biological Subcommittee of the U.S. Experiment Station Committee on Policy (ESCOP). In June 1993 he appeared before the House Committee on Agriculture's Subcommittee on Department Operations and Nutrition as an expert on bioherbicides.

In 1971-1972, he served as president of the Arkansas Academy of Science. In 1973 he received recognition from the Weed Science Society of America for publishing the outstanding article in weed science that year. He received the John White Award for Excellence in Agricultural Research in 1974 and was named a Fellow of the American Phytopathological Society in 1984. In 1996, the year he retired from full-time teaching, he received the Spitze Land-Grant University Faculty Award for Excellence. He died in Fayetteville shortly thereafter on November 24, 1996.