The collection consists of landscape architecture designs and plans by Robert Hale Ellis, Jr., a landscape architect based in Portland, Oregon. Most of the projects in the collection were executed in the Portland area, with a small number in Washington and California. Materials in the collection are primarily drawings by Ellis, and also include a number of diazotypes and blueprints. About half of the projects include drawings or prints of the buildings for which Ellis designed the landscaping, including buildings by noted regional architects Pietro Belluschi; Halsey Jones; DeWitt Robinson; Warren Weber; Glenn Stanton; and Sutton, Whitney and Aandahl. The collection also includes maps and documents relating to Ellis’ tract of land on Shaw Island in the San Juans that he donated to the University of Washington as a nature preserve.