In 1893 Lewis received a commission from the Pennsylvania Forestry Commission to paint a set of 50 watercolor illustrations of representative leaves of trees for display at the World's Columbian Exposition in Chicago. Lewis's work was regarded as a success, having won her a medal and a diploma, and the set of paintings was publicly displayed again at the 1901 Pan-American Exposition in Buffalo, New York, as well as the 1904 Louisiana Purchase Exposition in St. Louis.