He worked as an undergraduate as a student assistant to Louis Hermann Pammel, whom he accompanied on botanical surveys.
[1] His doctoral dissertation The Morphology of Bacillus Radicicola,[4] written under the supervision of Edwin O. Jordan, deals with nitrogen-fixing bacteria that live in the nodules of a variety of legume species.
[2] Two important bacteriologists in the early history of the department are Max Levine (1889–1967) and Chester Hamlin Werkman (1893–1962) (who was Buchanan's doctoral student).
[1] Buchanan was elected in 1913 a fellow of the American Association for the Advancement of Science.
[3] Their son Joseph Hall Buchanan became a patent attorney and a brigadier-general.