After the expansion, the Grenada facility will have 80 employees.
Fly Timber has operated in Grenada for 32 years.
It is a hardwood-only sawmill and currently saws hardwood into mats for the oil and gas industry and cuts trim-grade hardwood and floor-grade hardwood for use in residential and commercial construction.
Ricky Fly, owner of Fly Timber, says in a statement Tuesday that the expansion will enable the company to begin cutting railroad crossties, which will then be shipped to a lumber treatment facility by rail car.
The Mississippi Development Authority and Grenada County provided assistance to rehabilitate and add on to a county-owned rail spur.