Rocky outcrops in coastal Douglas-fir zone. Areas that dry out rapidly in summer. Low to middle elevations but occasionally higher. Absent from the wet outer coast. Occurs in BC extending south to California and east to Manitoba, Michigan, Colorado and Arizona (Pojar and MacKinnon, 1994; Ganders and Krause, 1986; Elle, 2002).
Medium textured soils (Klinka et al., 1989).
Nitrogen rich soils (Klinka et al., 1989).
pH 6 to 7. No tolerance of salinity (Klinka et al., 1989).
Dry to moderately dry (Klinka et al., 1989).
Shade intolerant (Klinka et al., 1989).
Early successional in fields and forests but persistent in open grasslands and rocky slopes (C. Burton, personal communication).
Common in Garry oak outcrop ecosystems (Erickson, 1996).