| 1942 - 1946 | Student Teacher, then Junior and Secondary Teacher with the Education Department of South Australia | 
| 1943 - 1946 | Bachelor of Science with Honours (BSc (Hons)) completed at the University of Adelaide | 
| 1947 - | Member of the ANZAAS (Australian and New Zealand Association for the Advancement of Science) | 
| 1947 - | Member of the Royal Society of South Australia | 
| 1947 | Grassland Ecologist on a survey of the South-East of South Australia with the Agronomy Department of the Waite Agricultural Research Institute | 
| 1948 - 1949 | Botanist on the American-Australian Scientific Expedition to Arnhem Land in the Northern Territory | 
| 1949 | Master of Science (MSc) completed at the University of Adelaide | 
| 1949 - 1950 | Senior Research Fellow in Botany at the University of Adelaide | 
| 1951 - 1952 | Councillor of the Royal Society of South Australia | 
| 1951 - 1954 | Lecturer in Botany at the University of Adelaide | 
| 1953 | Doctor of Philosophy (PhD) completed at the University of Adelaide | 
| 1955 - 1960 | Senior Lecturer in Botany at the University of Adelaide | 
| 1959 - 1960 | President of the Royal Society of South Australia | 
| 1961 - | Member of the Royal Society of Victoria | 
| 1961 | Verco Medal received from the Royal Society of South Australia | 
| 1961 - 1965 | Reader in Plant Ecology at the University of Melbourne | 
| 1964 | Acting-Head of the Department of Botany at the University of Melbourne | 
| 1966 - | Professor of Botany at the University of Queensland | 
| 1966 - 1978 | Head of the Department of Botany at the University of Queensland | 
| 1967 - | Member of the of the Royal Society of Queensland | 
| 1970 | Visiting Professor in the Department of Forestry at the University of Oxford, UK | 
| 1974 - 1975 | Doctor of Science (DSc) received from the University of Adelaide | 
| 1975 | Visiting Professor in the Department of Botany at the University of Leeds, UK | 
| 1976 | Research Medal received from the Royal Society of Victoria | 
| 1978 - 1984 | Member of the Scientific Advisory Committee of the World Wildlife Fund Australia |