Isaac Conroe was one of Montgomery County's most enduring sawmillers before 1900. His main offices and a sawmill were at Conroe but he operated mill locations at Egypt, about two miles to the southwest of the town; Haltom, location unknown; and his large sawmill at Beach, two miles east of Conroe, which he later sold to Trinity River Lumber Company.
The Beach sawmill may have operated from as early as 1881 by Isaac Conroe. Conroe bought about 1092 acres patented to J. G. Smith in the Clark Beach league on January 1, 1881, for $486. Conroe later bought, on July 16, 1894, 1,331 acres from F. A. Talley & Company. Conroe died in 1897. His son, William N. Conroe and daughters, Effie Conroe and Rowena Hart, sold the company to Theodore Keller of the Trinity River Lumber Company, on February 28, 1899. William and Effie Conroe and their sister Rowena Hart sold to Trinity River for $5,000 a total of 792 acres of Clark Beach league, that may have been earlier sold to Isaac Conroe by Keystone Mills Company, on July 12, 1900. They also for $9,730 delivered to Trinity River all lumber stacked at the Beach sawmill. The Conroes may have leased the mill from Trinity River until July 1904. On July 15, 1904, the mill was leased to J. W. Hobbs, who operated it until it closed. Southern Industrial and Lumber Review recorded that J. W. Hobbs was manufacturing lumber at a cut 0f 60,000 feet daily in 1906.
The mill was “permanently closed” on June 1, 1906, according to the American Lumberman, with operations transferred to Fostoria.