Weyerhaeuser is one of the world's largest private owners of timberlands. It is classified as a real estate investment trust (REIT). The company owns or controls more than 6 million acres of timberlands, primarily in the U.S., and manages another 14 million acres under long-term licenses in Canada. Weyerhaeuser also manufactures wood and cellulose fiber products. Founded in 1900, the company is headquartered in Longview, Washington, United States.