Braun was especially active in fieldwork, both during her active professorship as well as in retirement. She traveled over 65,000 miles in 25 years of investigations, most of it driving her own car. In addition to research nearby in Adams County, Ohio and more widely in the east, Braun made 13 trips to the western United States. She was assisted in her work by her sister Annette, an entomologist and authority on Microlepidoptera. Braun took numerous color photographs of the flora she encountered in her fieldwork, and displayed them as slides to illustrate her very popular lectures, both to university classes and the general public. In the hills of Kentucky during the period of Prohibition, Braun and her sister sometimes explored areas where moonshining was active; however, they maintained the trust of the local inhabitants, honoring local customs and not reporting illegal stills to authorities.