Soon he became assistant professor of
Pomology,
University of California at the Whittier Pathological Laboratory and at the
University of California Citrus Experiment Station, in
Riverside, California. He was Superintendent of the Citrus Experiment Station at
Mount Rubidoux in 1911–1912, and in that position was instrumental in selecting the site of the present Citrus Research Center and Experiment Station at Riverside. From 1913 to 1917, Coit was Professor of Citriculture,
University of California, Berkeley. Farm Advisor, Los Angeles County, 1917 to 1919. In 1919 he founded the "Coit Agricultural Service" and is today continuing in this line of service. Among agricultural organizations, Coit has served as director of the
Sierra Madre Lamanda Citrus Association, the
California Avocado Association in 1915 and again from 1923 to 1947, and served as president three terms. In 1924 he helped organize the
California Avocado Growers Association (now Calavo) and served as director until 1944. and "A peony check-list" including the leading varieties of peonies of which authentic descriptions can be found in horticultural literature... (Jan 1, 1907) ==Awards==