Berberis aquifolium or Mahonia aquifolium (commonly known as Oregon-grape or Oregon grape) is a species of flowering plant in the family Berberidaceae.
Berberis aquifolium is a native plant in the North American West from Southeast Alaska to Northern California, and eastern Alberta to central New Mexico, often occurring in the understory of Douglas-fir forests (although other forest types contain the species) and in bushlands in the Cascades, Rockies, and northern Sierras.
In some areas outside its native range, it has been classified as an invasive exotic species that may displace native vegetation.
It is valued for its striking foliage and flowers, which often appear before those of other shrubs. It is resistant to summer drought, tolerates poor soils, and does not create excessive leaf litter.