Upon graduation from Normal School in Regina in 1939 he taught school at McCord and then sewed in the Royal Canadian Air Force from 1941 to 1945. He took both his bachelorís and masterís degrees in agriculture at the University of Saskatchewan, graduating in 1950. He earned his doctorate in agriculture from Iowa State University in 1953.

Following graduation he began a 29-year career in research with Agriculture Canada. His special interest was oilseed crops and sweet clover. At the Central Research Station in Ottawa he became the research co-ordinator for forage crops in Canada. In 1964 he was appointed director of the Agricultural Research Station in Saskatoon, a post he held until his retirement in 1979.

He made important findings, especially in livestock bloat research, and was in demand as a speaker at agricultural forums and seminars. He was an enthusiastic supporter and participant in the annual University of Saskatchewan Farm and Home Week.

Ross Greenshields received international recognition, being given a senior research fellowship from the New Zealand government to study oilseed crops in that country.

Throughout his career he was a dedicated worker for his profession and his community. He served locally and provincially with the Saskatchewan Institute of Agrologists and as national president of the Agricultural Institute of Canada. He was a leader initiating the in-service training program for agrologists in Saskatchewan and Canada. He was one of the instigators of the Farm Lab program in Saskatchewan, promoting team effort of farmers, government and the university. He initiated the idea of a Sodbustersí Club to provide funding to launch the drive for a new university college of agriculture building, which has now become a reality.

Ross Greenshields was appointed honorary secretary of both the Saskatchewan Institute of Agrologists and the Agricultural Institute of Canada. In 1967 he was named a fellow of the AIC.