She and Elzada Clover were the first women to raft the entire length of the Grand Canyon in 1938, making scientific collections of plants along the way.
[3][4] Jotter's mentor at the University of Michigan, Elzada Clover, invited her to join a boating expedition along the Colorado River through the Grand Canyon in the summer of 1938, during her graduate studies.
The novelty of the women's involvement generated significant press coverage at the time; articles tended to focus on the botanists' gender, appearance, and age rather than their scientific goals.
The group set out in three boats built by the trip organizer Norman Nevills, the Wen, the Botany, and the Mexican Hat on June 20, 1938.
Other members of the initial group included: Eugene Atkinson, a zoology graduate student at the University of Michigan, Don Harris, an engineer with the U.S. Geological Survey, and Bill Gibson, an artist from San Francisco.
Their research was the only botanical survey of the Colorado River documenting the plant life before the Glen Canyon Dam significantly altered it beginning in 1966.
The group used Jotter and Clover's plant list from 1938 as the basis of their work to restore native species destroyed by the Glen Canyon Dam.