15 August 2005.
Wyoming, United States
Locality: Both sides of Horse Creek Road (Highway 211) at railroad crossing, 3 miles north of Federal, Laramie County.
Coordinates: 41.3386, -105.1447
(Map it)
Elevation: 2060m.
Georeference protocol: Lat/lon determined by GPS
Environment description: Gravelly chert soil, grassy roadsides, and railroad right-of-way, relatively flat.
Comment: Population size ~300; just past peak flowering. H. annuus also present.
Collector(s):