Throughout the 18th and 19th centuries, botanists paid frequent visits to the area to collect plant specimens. Among them were John Bartram, who crossed the Roan Highlands in the late 1730s while studying the botanical make-up of what is now the southeastern United States. Andre Micheaux followed in 1794, discovering several alpine species rarely found outside of the New England and Canadian latitudes. In 1799, John Fraser explored Roan Mountain, collecting specimens of rhododendron and noting the existence of the fir tree that now bears his name. Other early explorers included Elisha Mitchell, for whom Mount Mitchell is named, and Harvard botanist Asa Gray.