In the survey of southern hard pine, spruce, hemlock and juniper boards, planks and sawed and hewed timber, there shall be two (2) sorts: (1) The first sort shall be denominated merchantable, and shall include all boards, planks, joists and timber that are sound and square-edged and well sawed; and (2) The second sort shall be denominated refuse and shall include all other descriptions, with allowance for rot.