The plant Asclepias spp, commonly known as "Milkweed", is designated the official State wildflower of the State of Illinois.
5 ILCS 460/43
State wildflower
Known as the State Designations Act
The act spans §§ 5-460-1 to 5-460-95 (40 sections).
P.A. 100-371, eff. 8-25-17.
Official source: Illinois General Assembly. Reproduced from public-domain Illinois statutes; confirm against the official source for the current text. Not legal advice.