Nothing contained in §§ 7-31-38 to 7-31-42, inclusive, shall be construed as requiring the board of county commissioners of any county to lease any tract or tracts of land, nor to offer to lease the same, and said board of county commissioners shall have power to withhold any tract or tracts from leasing for oil or gas purposes, if in the opinion of said board the best interests of the county shall be served by so doing.
SDCL 7-31-43