During his early years he was associated with and led Sierra Club outings for several weeks at a time, after which he published "Base Camp Reports." Published from 1950 to 1956, these reports covered a wide range of subjects, including plant lists, insects, and ecology. His first such report, at the age of 14, summarized 506 plant collections representing 337 species collected in the Sierra Nevada Mountains in Inyo and Fresno Counties. G. Ledyard Stebbins was a counselor on this particular trip, identified by Raven as Prof. G. L. "Led" Stebbins.