Ratzeburg was born in
Berlin, the son of a professor at the
veterinary school of the
University of Berlin. He studied medicine and
natural sciences in Berlin and was primarily interested in botany. He became a
private lecturer at the University of Berlin in 1828, when he was in contact with
Alexander and
Wilhelm von Humboldt. Two years later,[1] he became professor of
natural history there at the invitation of
Friedrich Wilhelm Leopold Pfeil (1783-1859). He founded the botanic garden of forestry at Eberswalde, working there until his retirement in 1869. He returned to Berlin, where he resided until his death.
Ratzeburg was the author of important works on forestry and forest entomology, and is considered the founder of the latter discipline. He was notably interested in
parasitic species. From 1827 to 1834, he wrote Medizinische Zoologie (Medical zoology) with
Johann Friedrich von Brandt, which was a standard work for many years.
Die Forstinsekten, Berlin 1837–1844, three volumes and a supplement.; re-edition at Vienna 1885.
Die Waldverderber und ihre Feinde, Berlin, 1841, 8th re-edition of
Johann Friedrich Judeich (1828–1894) and
Hinrich Nitsche (1845–1902) under the title Lehrbuch der mitteleuropäischen Insektenkunde, Vienna, 1885, with a biography.
Die Ichneumonen der Forstinsekten, Berlin 1844–1852, three volumes. The parts are:
Medizinische Zoologie, avec Brandt, Berlin, 1827–1834, two volumes.
Abbildung und Beschreibung der in Deutschland wild wachsenden Giftgewächse, with
Johann Friedrich von Brandt (1802-1879) and
Philipp Phoebus (1804-1880), Berlin 1834; new edition in 1838.
Forstnaturwissenschaftliche Reisen, Berlin 1842.
Die Standortsgewächse und Unkräuter Deutschlands, Berlin 1859.
Forstwissenschaftliches Schriftstellerlexikon, Berlin 1872–1873.
In addition, Julius Theodor Christian Ratzeburg continued
Friedrich Gottlob Hayne's work Getreue Darstellung und Beschreibung der in der Arzneykunde gebräuchlichen Gewächse.