This series contains correspondence, diaries, articles, notebooks, articles, photographs, drawings, and notes gathered by Linda Lear for her biography on the life of Rachel Carson. These materials are gathered from numerous archives including the Rachel Carson papers held at the Beinecke Rare Book and Manuscript Libray as well as from associates and friends of Carson that Lear interviewed. This series contains the bulk of this research material used to write Rachel Carson: Witness for Nature. It also contains Linda Lear's chronologies of Carson's life and outlines and notes for the chapters.

The subseries follow the organization of the book. Subseries A-C, chapters 1-3, deal with Carson's early life and education. Subseries d-h, chapters 4-8 deal with Carson's career in the Fish and Wildlife service and the development of her writing career. Subseries I-M, chapters 8-13 outlines Carson's success as a writer, the development of her close friendship with the Freemans and changes in Carson's family life. Subseries N-P, chapters 14-16 details the research and writing of Silent Spring. Subseries Q-S, chapters 17-19, describe the publication and reception of Silent Spring as well as the death of Rachel Carson.