27 September 2007.
Arizona, United States
Locality: South side of Highway 70, 1.5 miles southeast of junction with Highway 191, Safford.
Coordinates: 32.8219, -109.6878
(Map it)
Elevation: 896m.
Georeference protocol: Lat/lon determined by GPS
Environment description: Ditch between highway and railroad. Sandy loam soil.
Number of plants sampled: 250
Comment: Population size ~2000, near peak flowering.
Collector(s):