Okla. Stat. tit. 8, § 143

In any county of this state, the board of county commissioners is hereby authorized and empowered to utilize employees under its jurisdiction and county-owned tools, machinery, equipment, and materials for the purposes of opening and closing graves and maintaining and improving any publicly owned cemetery or other cemetery within the county not owned and maintained by an individual or private organization; provided that, where appropriate, a reasonable fee, not to exceed the actual cost of the service, may be charged for such services.