Vale Dr Jeff Ladd

Born in Adelaide in 1931, Jeff obtained his BSc (Hons.) 1^st Class in 1952 and MSc at the University of Adelaide in 1954. He was appointed to CSIRO Division of Soils as a Research Officer in 1954 to study the oxidation of hydrocarbons in soilsfor oil exploration. He obtained his PhD at Sheffield University, UK, in 1959. After several visiting scientist positions overseas, he was appointed as Senior Principal Research Scientist in 1974, later serving as head of the Soil Biology Section from 1987–1989 and also as Program Manager of the Soil Nitrogen and Organic Matter Program.

His research in soil microbiology, the biochemistry of soil organic matter and the cycling of nitrogen and carbon in cereal agroecosystems represented a major contribution to world soil science and agriculture. He is particularly remembered for hisr esearch on microbial biomass in the turnover of soil carbon and nitrogen. He built up a small team whose studies, using ¹⁴C and ¹⁵N to follow carbon and nitrogen through the economically important wheat-soil system, earned him a well-deserved place among the world leaders in this field.

He retired in 1995, and was an Honorary Research Fellow in CSIRO Land and Water from 1995 – 2005.  For his achievements in soil science, Jeff was awarded the prestigious Prescott Medal of Soil Science by the Australian Society of Soil Science in 1993 and honoured with a lifetime achievement medal presented to him at the Enzymes in the Environment Conference in Grenada, Spain, in 1999.

He was a highly modest, motivated and innovative scientist who will be remembered with great affection by many current and former CSIRO colleagues.

Jeff is survived by his wife Margaret, two sons and four grandchildren.