Cass Lumber Company of San Augustine County ran a lumber facility in the Steep Creek community during the first decade of the twentieth century. In 1904 J. J. Bland, a San Augustine sawmiller, controlled its out put. The mill had been shut for several months in 1905 when Cass Lumber Company approached the Santa Fe and offered to buy the James Hank Survey; the offer was $25,000. Santa Fe declined the offer.
American Lumberman noted in February 1906 that a recently concluded purchase of timber lands revealed that an acre which had sold for $5 to $8 a few years earlier had increased in value to $30 an acre. Cass Lumber Company sold three million feet of lumber for $10,000 to Rockwell Bros. Lumber Co. of Houston. The lumber was located at Cass Lumber's yards, sheds and dry kilns at Steep Creek.
The sawmill operation also had a planing mill. San Augustine County Chattel Mortgage records note that Cass Lumber Company mortgaged to Hall & Brown for $1885 a #34 Hall & Brown 8-inch by 15-inch new style fast-feed matcher with flooring heads, a Berlin 12-inch inside moulder with a second head, and a total of five heads on 25 March 1914.
The company operated a tram road, for the company in November 1908 bought from Henry and Harris of Lamerle, Sabine County, a 15-ton Standard gauge locomotive, more than a 100 tons of steel rails, and five standard gauge logging cars.
The Southern Industrial and Lumber Review in March 1909 reported that a cyclone [tornado] virtually demolished the lumber mill of the Cass Lumber Company at Steep Creek on February 19, 1909. Some injuries but no deaths were reported. No record exists of the plant being rebuilt