Comprised of notes documenting experiments on plants and trees. For some it is not entirely clear under what circumstances or at what time period the experiments were conducted. Many were carried out while attending The University of Leipzig in Germany. The bulk of the experiments pertain to the field of physiological botany such as "Measuring the Force of Gravity in Plants," "Partial Pressure of Oxygen on Protoplasm," "Correlative Growths Resulting from Mutilation and Pruning," and many others. Drawings and sketches depict Stone's original designs and use of apparatus.

Comprises various reports published by Stone and others on topics such as shade trees, plants in different parts of the United States, effects of light, smoke and ice storms on vegetation, and pruning and restoration of trees. Bound volumes of published clippings and articles authored by Stone, including his writings for Arborea, the bulletin of the Massachusetts Tree Wardens and Foresters Association, can also be found in this series.

Contains principally handwritten and typewritten lecture notes, college-related correspondence, reports, and some personal reminiscences of life at the Massachusetts Agricultural College. Many of the letters in this series are written by Stone to various State Commissioners of Education and the Presidents of the College, and concern the buying of land, location of future buildings, reorganizations of present departments, and future courses.

Comprises biographical materials (resumes, genealogy, biography and tributes), a bibliography of published writings, materials documenting memberships in professional organizations and societies, professional directories, clippings, memorabilia, comments on Emily Dickinson, and miscellaneous correspondence. Much of Stone's correspondence was with former students and members of the numerous societies in which he was involved. These letters discuss municipal tree problems, legislation to establish licensing of arborists in Massachusetts, the valuation of shade and ornamental trees, and other related subjects.

Also in this series are nine albums of photographs, and two of printed illustrations labeled "cuts" by Stone. A few are Stone's personal photographs of himself, and presumedly his family and friends. However, most of the photographs relate to his life-long interest in the tree profession.

Contains numerous notes and clippings on what appears to have been a prime interest and hobby for Stone. There are clippings on such topics as television, mental telepathy, visual transmissions and various types of clairvoyance. Stone was a member of the American Psychical Society and the Boston Society of Psychic Research, and many of his papers are notes on experiments relating to these subjects.

The student herbarium of Waldo Barlow, displayed at the St. Louis Exposition of 1904.