505 ILCS 100/9
Notices for control and eradication of noxious weeds shall be on a form prescribed by the Director and shall consist of 2 kinds: general notices and individual notices. Failure to publish general weed notices or to serve individual notices as provided in this Section does not relieve any person from the necessity of full compliance with this Act and regulations thereunder. In all cases such published notice is legal and sufficient notice.
General notice shall be published by each Control Authority, or any combination of Control Authorities among counties, in one or more legal newspapers of general circulation throughout the area, or areas, over which the Control Authority, or Control Authorities, have jurisdiction at such times as the Director may direct or the Control Authority may determine.
Whenever any Control Authority finds it necessary to secure more prompt or definite control or eradication of noxious weeds than is accomplished by the general published notice, it shall serve individual notices upon the person owning and the person controlling such land, and give notification of such notice to the record owner of any encumbrance thereon, giving specific instructions and methods when and how certain named weeds are to be controlled or eradicated.
505 ILCS 100/9