Theodor Magnus Fries

Theodor Magnus Fries
Image of Fries from Ignaz Dörfler (published 1906–1907) Botaniker Porträts
Born	(1832-10-28)28 October 1832[1] Femsjö, Sweden
Died	29 March 1913(1913-03-29) (aged 80) Uppsala, Sweden
Nationality	Swedish
Scientific career
Fields	Botany, Lichenology
Author abbrev. (botany)	Th.Fr.

Theodor "Thore" Magnus Fries (28 October 1832 – 29 March 1913), was a Swedish botanist, lichenologist, and Arctic explorer. The son of the renowned mycologist Elias Magnus Fries, he served as a professor of botany and applied economics at Uppsala University from 1877 and as the university's rector from 1893 to 1899. He made significant contributions to lichenology, particularly through his work Lichenographia scandinavica (1871–1874), and introduced innovative research methods including the systematic use of microscopy in botanical studies. He was elected to the Royal Swedish Academy of Sciences in 1865 and was awarded the Order of the Polar Star in 1903.

Fries participated in two Arctic expeditions led by Adolf Erik Nordenskiöld, traveling to Bear Island and Spitsbergen in 1868 and to Greenland in 1871. As an educator, he emphasised hands-on practical instruction in botany and mentored several botanists who went on to make significant contributions to the field. He made substantial contributions to preserving Carl Linnaeus's legacy, including publishing a two-volume biography of Linnaeus (1903) and managing the Linnaean Foundation at Hammarby. His three sons, Robert Elias, Thoralf Gustaf Elias, and Thore Christian Elias, all pursued academic careers, continuing the family's botanical and scholarly traditions.