He then returned to be Lecturer in Botany at Queen's University between 1960 and 1965 and was subsequently promoted to Reader in 1965 and then awarded a Personal Chair of Plant Physiology in 1970.
[3] His research focused on plant ecology and physiology, particularly the relationship between the phloem and xylem and carbon and nitrogen transfer.
He made extensive investigations of the latter in root nodules, using peas as an experimental system, inspired by his childhood experiences.
[5] He also led work on the native flora of Western Australia, using his expertise to increase understanding of how the plants dealt with stressful environments, through both anatomical and physiological adaptations especially to their roots.
His work helped increase productivity of pastures and crops, and also development of more sustainable land management systems.