19 September 2010.
Arizona, United States
Locality: Near Lot 2B, along road to Middle Tank, and northwest of FR 486 (Helvetia Road), Santa Rita Experimental Range of the University of Arizona, Pima County.
Coordinates: 31.8340, -110.8565
(Map it)
Elevation: 1111m.
Georeference protocol: Lat/lon determined by GPS
Environment description: Shade. Level ground. Sandy soil. Under Prosopis trees.
Number of plants sampled: 100
Comment: Plants locally common; may be protected from grazers by the shelter of woody plants.
Collector(s):