At Shafter, Leigh focused his research on the biology, ecology, host plant resistance, control and management of insects and spider mites on cotton. He stood at the forefront of Integrated Pest Management (IPM) of cotton pests, according to an article in the summer 1994 edition of American Entomologist. He taught courses on cotton IPM and host plant resistance.
“During his career, he advised many graduate students who went on to become renowned entomologists in cotton IPM around the world,” wrote Charles E. Jackson of Uniroyal Chemical, Clovis, Calif., and J. Hodge Black, UC Cooperative Extension, Bakersfield in the American Entomologist. For his achievements in teaching and research, Leigh received the James H. Meyer Recognition Award for Distinguished Achievement Service Award in 1988.
The Pacific Branch of the Entomological Society of America awarded him the C. F. Woodworth Award for outstanding service to entomology in 1991. Charles W. Woodworth (1865-1940) founded the Entomology Division of the University of California, Berkeley, and is considered the founder of the UC Davis Department of Entomology.
'Leigh's caring, enthusiasm, intellect, expertise and professionalism were regarded highly by all who knew him.'
—American Entomologist
Leigh was born March 6, 1923 in Loma Linda. A 1942 graduate of Beaumont High School, he worked briefly on a farm and then served in the U.S. Army during World War II.
His work as an agricultural inspector with the Riverside County Agricultural Commissioner's Office from 1944-1945 sparked his interest in entomology. He received his bachelor of science degree in entomology from UC Berkeley in 1949, and his doctorate in entomology there in 1956. His thesis was on the influence of light, temperature and humidity on flight activity of the butterfly, Colias and involved both field and laboratory investigations.
Leigh served as an assistant professor at the University of Arkansas from 1954 to 1958, where he worked on the biology, ecology and control of pink bollworm and boll weevil, using chemicals and cultural means. He joined the UC Davis Department of Entomology, advancing from assistant entomologist to associate entomologist in 1963. In 1968, he was promoted to adjunct lecturer and entomologist.
Leigh served as president of the Pacific Branch of ESA in 1981. He also served on the ESA Governing Board and was a founding member and past president of the American Registry of Professional Entomologists (ARPE). In 1981 he received the ARPE Outstanding Entomologist Award. In 1993, Leigh was elected as a director to the Board Certified Entomologists' certification board.
In addition, Leigh was active in the American Association for the Advancement of Science and was the founding president of the San Joaquin Entomology Association. He held membership in several other associations, including the Association of Applied Insect Ecologists, the Ecological Society of America, and the American Archeological Society. The UC Davis entomologist was a past president of the Shafter Rotary Club and also active in the Boy Scouts of America.
During his 37-year career, he authored more than 127 peer-reviewed publications.
“His many colleagues considered his research and teaching to be outstanding,” wrote authors Jackson and Black in the American Entomologist. “Leigh's caring, enthusiasm, intellect, expertise and professionalism were regarded highly by all who knew him.”
In his memory, his family and associates set up the Leigh Distinguished Alumni Seminar in Entomology Fund at the UC Davis Department of Entomology. The alumni seminar is now known as the Thomas and Nina Distinguished Alumni Seminar, memorializing Dr. Leigh and his wife, Nina Eremin Leigh (1929-2002). The family includes two sons, Michael and Nicholas.