12 October 2008.
Illinois, United States
Locality: Along 2150 North Road, east of Irvington, NE 1/4 of SW 1/4 of Section 15, T1S, R1E, Walnut Hill Quad, Jefferson County.
Coordinates: 38.4383, -89.0783
(Map it)
Elevation: 161m.
Georeference protocol: Lat/lon determined by GPS
Number of plants sampled: 5
Associated species: Asclepias syriaca, Cercis canadensis, Helianthus strumosus, Juglans nigra, Platanus occidentalis, Quercus imbricaria, and Sassafras albidum.
Comment: Majority of specimens had poor quality seeds due to presence of weevils.
Collector(s):