October 1998.
Illinois, United States
Locality: Koempken Centennial Prairie, west of Huntley, McHenry County.
Environment description: A sizable, naturalized population at a privately owned mesic prairie.
Comment: Species is not native to this part of Illlinois. However, judging from the number and size of plants, this population has been on this site for many years.
Collector(s):