In 1907 Thompson Brothers Lumber Company built a mill and 37 acre pond at Trinity, and Texas Long Leaf Lumber Company, which started at Willard in 1912, bought the Trinity mill in 1922. Under the management of Paul Sanderson for 22 years, the company became one of the nation's most successful manufacturers of Yellow Pine and southern hardwoods, and Sanderson worked with forest landowners in Texas to promote selected cutting, reforestation, fire protection, and the removal of defective trees. By 1937 the mill was producing 3.5 million board feet monthly, cutting Long Leaf, Short Leaf, and Loblolly Pine, Oak, Gum, Ash, Magnolia, and other woods. The company's main office was at the 205 acre mill site in Trinity, with additional sales offices in Houston and St. Louis, and it was one of Trinity's largest employers, with as many as 450 employees. During World War II, production reached 140,000 board feet daily, lumber was flown to Europe and Africa, and the company received the Army-Navy "E” Award in a March 17, 1944, ceremony in Trinity. Sanderson then pursued a broad public campaign for postwar planning and the perpetuation of the timber industry in Texas, emphasizing timber as a renewable natural resource. At the time of his death in October 1944, he held many civic and lumber industry offices, including president of the Southern Pine Association, president of the Texas Forest Association, and chairman of the Texas Prison Board. In 1953 Texas Long Leaf timber interests totaled 252,230 acres in six east Texas counties, but the mill's closing in 1955 devastated the local economy and ended a long chapter in Trinity's history.