Oskar Eberhard Ulbrich (17 September 1879 – 4 November 1952) was a German botanist and mycologist.
He studied natural sciences at the University of Berlin, where his instructors included Adolf Engler (1844–1930) and Simon Schwendener (1829–1919).
In 1926 he became a curator and professor at the Botanical Museum in Berlin, where in 1938 he was appointed director of the Hauptpilzstelle.
[1] Known for his intrafamilial investigations of the botanical families Amaranthaceae, Chenopodiaceae and Caryophyllaceae, in 1934 he subdivided Chenopodiaceae into eight subfamilies; Salicornioideae, Polycnemoideae, Chenopodioideae, Salsoloideae, et al.[2][3] In 1911 he introduced usage of a color scheme to indicate geographical regions on herbarium specimens and fascicles.
[4] The plant genus Ulbrichia from the family Malvaceae was named after him by Ignatz Urban (1848–1931).