65 ILCS 5/11-20-6.5: Milkweed classification.

(a) For purposes of this Section, "milkweed" means Asclepias syriaca or other native Asclepias species.

(b) The corporate authorities of a municipality may not classify milkweed as a noxious or exotic weed.

(c) A municipality may not classify milkweed in a manner inconsistent with this Section. This Section is a limitation under subsection (i) of Section 6 of Article VII of the Illinois Constitution on the concurrent exercise by home rule units of powers and functions exercised by the State.