The wood used here is called antique heart pine.  The tree has been extinct for nearly 40 years and its wood is available only from remilling old warehouses and large buildings torn down.  This setting is in a historical 250 year old home in Philadelphia.  The steps are original to the home and the new floor was selected to match the existing old wood.  The wood was nailed on top of the original subfloor, sanded down and coated with 2 coats of commercial grade polyurethane.