Richard A. Dummer commenced his career as a trainee gardener at the Cape Town municipal gardens, under Mr. Ridley. In his spare time he collected plants, mainly on the Cape peninsula, and identified them at the herbarium of the South African Museum. During 1907 he presented many of the rarer plants of the Cape peninsula to the museum, some of them new to its collections. He continued his donations during the next two years. In 1909 these included a species of Vangueria from the Transvaal which was new to the museum. His contributions from Namaqualand and the Western Cape were acknowledged in the preface to Volume 5.1 (1912) of the Flora Capensis by the editor, W.T. Thiselton-Dyer*.
In 1910 Dummer went to Kew Gardens, London, as a student gardener. The next year he left to become assistant to Professor A. Henry, who was involved as co-author in the preparation of a book on the trees of Britain and Ireland. Dummer subsequently worked in the herbaria and libraries at Kew, the British Museum, Linnaean Society, and the universities of Oxford, Cambridge and Edinburgh. During this time, from 1912 to 1914, he published ten taxonomic papers and notes relating to South African plants. These included a description of the new genus Pearsonia and several new species. Two of the papers, "A revision of the genus Alepidea De la Roche", and "A synopsis of the species Lotononis, Eckl. & Zey., and Pleiospora, Harv.", were published in the Transactions of the Royal Society of South Africa (1913, Vol. 3, pp. 1-22; 275-336). In 1914 he started working for the Kivuvu Rubber Co. in Kampala, Uganda. He collected flowering plants and fungi in his spare time, and undertook a botanical expedition to Mount Elgon, on the border between Uganda and Kenya. The results of this expedition were reported in "The vegetation of the crater and summit of Mount Elgon" (Gardners Chronicle, 1919).
Returning to South Africa he spent a year organising his collections in local herbaria and published two notes in the Annals of the Bolus Herbarium, one on several new species of the genus Adenandra and the other a further contribution on the genus Agathosma (1920, Vol. 3, pp. 40-43; 44-62). Two years later he was killed in a motorcycle accident in Uganda, aged 35 - a premature end to the career of a talented and likeable young man. The more than 20 000 specimens he collected can be found in the herbarium of the South African Museum, the National Herbarium in Pretoria, and various overseas herbaria.