Formerly Simpson Resource Company, Green Diamond Resource Company (which changed its name in May 2004) is privately owned by the descendants of Sol Simpson, who founded Simpson Logging Company in 1890 near Shelton, Washington. Soon after the founding of the company, Sol established a reputation for innovation in forestry. He introduced the use of horses in the forests, was one of the first to offer loggers a company health plan, and introduced technology into forestry in the form of the "Walking Dudley," a mechanized log-hauling machine. Since that time, the company has grown to include timberlands and lumber manufacturing operations. The company is still privately held and managed with the same long-term commitment to environmental stewardship.
Colin Moseley is the chairman of Green Diamond Resource Company, and is the fifth generation of direct Simpson lineage to be chairman. He is the son of Furman Moseley, whose grandfather-in-law was Mark E. Reed, who was Sol Simpson’s son-in-law. Colin Moseley has been with the company since 1988, and chairman since 1996.
The company owns timberland in Washington, Oregon and California with headquarters in Seattle. Throughout the three states, about 350 people are employed by Green Diamond Resource Company.