James G. Horsfall

James Gordon Horsfall (January 9, 1905 – March 22, 1995) was an American biologist, plant pathologist, and agriculturist. The New York Times described Horsfall as a "leading plant pathologist."

Early life and education Horsfall was born in Mountain Grove, Missouri, and was raised in Monticello, Arkansas. The family came from ship owners in Liverpool. Horsfall's father was interested in horticulture and worked at an experimental fruit growing station. Horsfall studied at University of Arkansas, initially with an interest in cars and engineering. He worked briefly with Dwight Isely, counting insects to determine the timing of insecticide application in cotton. He found himself sidelined, which he claimed was due to his nonconformity. After graduating with a Bachelor of Science degree in 1925, he studied plant pathology at Cornell University, from which he received his doctorate in 1929. His brother, William R. Horsfall, also a Cornell graduate, became a noted entomologist. It was however found to break down in sunlight. Horsfall tried 2,3-dichrolo-1,4-naphthoquinone as a substitute. Horsfall later discovered that sugar concentrations in plant parts was correlated with resistance to fungal infection by Alternaria in potatoes. He was also a member of the National Academy of Sciences.

Personal life In 1927, Horsfall married Sue Belle Overton. The couple had two daughters: Margaret Eleanor Schadler and Anne Vaulx Thomas.

Horsfall died on March 22, 1995, at the age of 90. He was interred in New Haven's historic Grove Street Cemetery.