5 ILCS 585/1

Consent of the State of Illinois is given to the United States for the acquisition by purchase, gift, or condemnation with adequate compensation, of such lands in the State of Illinois as in the opinion of the Federal Government may be needed for the establishment, consolidation and extension of national forests in the State. The State of Illinois retains concurrent jurisdiction with the United States over such areas in the matter of the service thereon of all civil and criminal process issuing under the authority of the State of Illinois.