Stella Melugin Coakley was born in 1947 in Modesto, California and raised on a farm. She attended Modesto Junior College as a Biology major and discovered an interest in plant pathology, later earning a BS in Plant Sciences at the University of California Davis, followed by an MS (1970) and PhD (1973) degrees in Plant Pathology, also at UC Davis. In 1972 she moved to Colorado with her husband while still writing her doctoral thesis on post-harvest disease in iceberg lettuce. After earning her doctorate, she taught introductory plant pathology and human physiology courses at the University of Denver. In 1975, the same year that the first of her three daughters was born, Coakley was accepted as a fellow of the National Center for Atmospheric Research, where she studied the impacts of climate change on crops.
Coakley’s research interest in stripe rust afflicting Pacific Northwest wheat crops fostered a broader connection with Oregon. In 1988 she was hired as chair of the Botany and Plant Pathology department at Oregon State University, where she continued to research septoria diseases. She served as president of the OSU Faculty Senate in 2004 and, that same year, moved into the role of Associate Dean of the College of Agricultural Sciences. In this capacity, Coakley led the university space committee, which was closely involved with the construction of the INTO and LINC buildings on the OSU campus. She was likewise integral to the creation of the Marine Mammal Institute, and has served on the board of the Agricultural Research Foundation, helping provide grants for young faculty members at the university. She retired from OSU in 2015.