These records of the Potlatch Lumber Company, of Potlatch, Idaho, span the years 1890 to 1949, with the bulk of the material covering the years 1901 to 1932.

The records include the correspondence of Walter D. Humiston, assistant general manager and director of research, several early contracts, leases, deeds and conveyances, property tax records and the results of numerous timber cruises. There are twelve folders of material from the Washington, Idaho and Montana Railway Company as well as individual folders containing material relating to Potlatch subsidiaries such as the brick company, dairy ranch, and flour mill, as well as the incorporation of the town of Elk River.

In addition to this record group the University of Idaho library has several manuscript collections of Potlatch related material, including the records of Potlatch Lumber Company, 1901-1979 (MG 135, 111 cubic feet); and Washington, Idaho and Montana Railway Company, 1903-1962 (MG 139, 65.5 cubic feet).