He was born on a farm in Clark County, Ohio, graduated from Antioch College in 1901 and from the University of Chicago (Ph.D.) in 1904, served as botanical expert to the Bureau of Plant Industry in 1903–04, and thenceforth was a botanical investigator of the Carnegie Institution at the Station for Experimental Evolution, Cold Spring Harbor, N. Y., giving special attention to the results of Luther Burbank's work.
Shull played an important role in the development of hybrid maize (in the USA, popularly 'corn') which had great impact upon global agriculture.
He was called George in distinction from his son Harrison Shull (1923–2003), also a distinguished scientist, specializing in the quantum mechanics of small-molecule electronic spectra.
[9][10] A reference to George H. Shull's discovery of the process of heterosis is in the movie "High Time" starring Bing Crosby about a wealthy man going back to college to get his bachelor's degree.
When quizzing with a younger fraternity brother, Crosby's character asks "Who discovered the process of heterosis?"