One of the United States' most prominent botanists, James L. Reveal has joined forces with A. Scott Earle (a retired surgeon and professor) to follow the Corps of Discovery's trail, focusing on the plant specimens that Capt. Meriwether Lewis "collected for Mr. [Frederick] Pursh," President Jefferson, and other scientists of the early 19th century. Earle's and Reveal's seasonal color photographs illustrate complete botanical descriptions of each plant, which are accompanied by quotes from Lewis's journal about it, along with comments from scientists of his day and since. One of the United States' most prominent botanists, James L. Reveal has joined forces with A. Scott Earle (a retired surgeon and professor) to follow the Corps of Discovery's trail, focusing on the plant specimens that Capt. Meriwether Lewis "collected for Mr. [Frederick] Pursh," President Jefferson, and other scientists of the early 19th century. Earle's and Reveal's seasonal color photographs illustrate complete botanical descriptions of each plant, which are accompanied by quotes from Lewis's journal about it, along with comments from scientists of his day and since. A. Scott Earle attended Harvard College, with time out during World War II to serve in the Army's famed 10th Mountain Division. The Army's rugged training in the Colorado Rockies instilled in him a life-long love of mountains. He lives in Idaho where he has spent his retirement years photographing and writing about mountain flora. James L. Reveal is the author of more than 350 scientific articles and books. His research interests range from floristics and monographic work to aspects of botanical nomenclature and the history of scientific explorations and discoveries in temperate North America. He lives in Colorado.