His first appointment was in January 1936 as pasture ecologist at the Pasture Research Section, part of the Division of Plant Industry. He set out to do botanical surveys of new pasture research stations. In 1945, he was transferred to
Estcourt to the Botanical Survey Section of the Division of Botany and Plant Pathology which later became the Botanical Research Institute. From 1948, he was permanently posted at the
Grootfontein College of Agriculture in Middelburg. Acocks contributed greatly to South African botany in three distinct areas. Firstly, his treatment of the vegetation regions (Veld Types) of South Africa, in which he classifies vegetation into 75 classes, continues to be a valuable reference work for researchers and is an outstanding achievement for a single individual. Secondly, his analysis of the impact of humans on vegetation has largely been revised by current research insights, specifically with regard to the effect of fire on grasslands, savannas and forests. There is, though, ample evidence showing considerable changes in Karoo fauna and flora over the last three centuries. Finally, his pioneering views on veld rehabilitation and management remain important guidelines for the farming communities of South Africa. He was President of Section C of the
SA Assoc. for the Advancement of Science in 1963, and awarded the Senior Capt. Scott Medal by the
SA Biol. Soc. in 1977. Acocks worked on a revised version of the
Veld Types, which he completed shortly before his death, and which is lodged in the archives of the National Botanical Institute (NBG). His second book,
Key Grasses of South Africa, was published in 1990. == Legacy ==