The District has a two-tier seed provenance system for purchase consideration of Southern-Sourced Seed native plant material. First-Tier priority is given to species with origins (provenance) from locations within the attached range maps.  Any seed that does not originate from the defined First-Tier Zone may be considered for purchase at the District’s discretion as long as vendor provides the seed’s geographic location (County & State) and mile distance from Lake County, Illinois in the “Notes” column found in the contract’s Schedule of Prices.