United States, California, Contra Costa, Contra Loma Regional Park. In area #8. On top of hill ca. 600 yds. sw of main parking lot ca. 800 yds. w of Contra Loma Blvd.
37.970278 -121.833333 +-402m. NAD83
37§ 58m 13s N; 121§ 50m W
152 meters
500ft.
Soil clay. On top of large hill. Accompanying species include Bromus rigidus, Avena fatua, and Avena barbata.