Oregon-grape is abundant on north-facing slopes [133,151]. It occurs in dry to moist foothill shrublands and montane areas [68,85,99,109,110,124,135,157,210,214,216] with sparse understory vegetation . Oregon-grape also occurs in moist sites on plains, low-elevation woodlands [119,133], riparian areas, and occasionally wetland areas . Oregon-grape is among the most resistant plants to winter sun exposure .
|Arizona||5,000- 8,500 feet (1,500-2,600 m) |
|California||1,000-7,200 feet (300-2,200 m) |
|Colorado||5,500-10,000 feet (1,700-3,100 m) |
|Nevada||5,000-10,000 feet (1,500-3,100 m) |
|New Mexico||6,500-10,000 feet (2,000-3,100 m) |
|Texas||4,500-8,000 feet (1,400-2,400 m) [157,210]|
|Utah||3,600-9,800 feet (1,100-3,000 m) |
Soil: Oregon-grape is found in medium-textured, well-drained sandy loam, chalky, or granitic soil in coniferous forests [34,71,213] and sometimes on shallow, rocky sites where other vegetation is sparse [46,213]. Oregon-grape grows well on soils derived from limestone and quartzite in western Montana . It is intolerant of poor drainage and high water tables [85,156,213] and is weakly tolerant to saline soils . Oregon-grape is tolerant of very strongly acid to mildly alkaline soils [34,213] with pH ranging from 4.6 to 7.6 [34,182,185,189].
Climate: Oregon-grape tolerates a wide range of climates including xeric continental [81,142], Pacific maritime, core maritime, northern and southern continental [142,176,188], and subhumid montane .