Arnoldia has a long history of publishing interdisciplinary writing about trees and other temperate woody plants. The magazine was established as the Bulletin of Popular Information in 1911. The Arboretum's founding director, Charles Sprague Sargent, viewed the publication as a means of alerting visitors to the "flowering of important plants" in the Arboretum's collections. Initially, the Bulletins were issued only during the growing season, and with a Bulletin in hand, there was no reason a visitor should miss the flowering or fruiting of any plant on the grounds.
After Sargent's death in March 1927, Ernest Henry Wilson assumed responsibility of the publication. Other than the addition of illustrations, however, the publication continued to be a seasonal guide filled with information on the phenology, history, and culture of the Arboretum's plants. It was not until Wilson's untimely death in 1933 that the content began to expand. Edgar Anderson, best known for his later work at the Missouri Botanical Garden, edited the publication for the next four years, and while "plants of current interest" remained a regular feature, staff members began to contribute longer articles, with new interdisciplinary topics including ethnobotanical uses of plants, botanical art, and landscape history.
Donald Wyman took over the editorship in 1936, and in 1941 Director Elmer Drew Merrill, who was partial to one-word titles, changed the Bulletin of Popular Information into Arnoldia, honoring benefactor James Arnold. Wyman wrote the lion's share of its articles for over thirty years. A remembrance in 1993 recognized his contributions: "More, perhaps, than any other single person, certainly of his era, he advanced the knowledge of hardy woody plants through his articles published in Arnoldia and elsewhere . . . His work may now seem familiar, but only because it's been so often imitated."
After Wyman's retirement, other editors expanded the content—attracting an even wider variety of scholarship—and, along the way, created an essential forum for conversations about trees and other temperate woody plants.