Edmund Frederic "Heff" Warburg (22 March 1908 – 9 June 1966) was an English botanist, known as the co-author of two important British floras.
His father was an enthusiastic amateur botanist, and the garden of their house at Headley, Surrey, contained a large collection of plants, particularly Cistus, Berberis, and oaks.
In 1938 Warburg became assistant lecturer at Bedford College, London, but during the war in 1941 he joined the Royal Air Force and was attached to the photographic interpretation unit at RAF Medmenham in Buckinghamshire.
Here his first task was to move of the herbarium from the house of its founder, George Claridge Druce, in Crick Road to the newly built botany school.
He developed the reputation of a patient teacher and a dedicated field botanist, with a wide knowledge of the British flora.
He was a founder member of the Berkshire, Buckinghamshire and Oxfordshire Naturalists' Trust and later a vice-president; one of their properties, rich in interesting flora, was in 1967 named the Warburg Reserve in his memory.
Warburg was generally known by colleagues and friends as "Heff", partly in punning references to his initials "E. F." but also with the suggestion of Heffalump, for he was physically a big man.