Joseph Burtt Davy (7 March 1870 Findern, Derbyshire – 20 August 1940 Birmingham) was a Quaker botanist and agrostologist. He was the first curator of the Forest Herbarium (FHO) at the Imperial Forestry Institute when it was founded in 1924 under the Directorship of Professor Robert Scott Troup.
He attended school at Ilkley in West Yorkshire. In 1891, he joined Kew Gardens as a technical assistant, leaving shortly after for the United States where he enrolled in the botany department at the University of California. Here he studied agriculture from 1893–96 and took up the post of botanist at the Agricultural Experiment Station in California between 1896-1901, describing the Cyperaceae and Gramineae for A Flora of Western Middle California by Willis Linn Jepson. Here he also met his wife-to-be, Alice Bolton (1863-1953), a native Californian.
In early 1903, he was appointed botanist and agrostologist with the newly founded Transvaal Department of Agriculture. Burtt Davy wasted no time in starting a collection of Transvaal plants, a process by which he acquired an intimate knowledge of the subject. These first specimens came from Meintjieskop, Irene and a trip to the western Transvaal - at the time of his retirement in 1913, his collected specimens numbered 14,000.
Burtt Davy's appointment led directly to the founding of the Division of Botany. This later became the Botanical Research Institute (BRI) and then the National Botanical Institute (NBI) in 1989 when it amalgamated with the National Botanic Gardens. Still not content, bureaucracy stepped in once more in 2004 and it was renamed the South African National Biodiversity Institute (SANBI).