Frederick Traugott Pursh
Frederick Traugott Pursh (1774 - 11 July 1820) was a German-American botanist. Born in Grossenhain, Saxony, he was educated at Dresden Botanical Gardens, and emigrated to the United States in 1799. By 1805, he was working for Benjamin Smith Barton on a new flora of North America, under who he studied the plants collected on the Lewis and Clark Expedition.
Barton's proposed flora was never written, but Pursh, who then moved to London, England, did make a major contribution to North American botany in his Flora americae septentrionalis, published in 1813. He then returned to America, moving to Canada in 1816. His hopes of carrying out further major work were prevented by ill health due to alcoholism, and he died destitute in Montreal.
His name is commemorated in the genus Purshia (Bitterbush) and in several species, e.g. Rhamnus purshiana. The standard botanical author abbreviation Pursh is applied to species he described.