Mahonia aquifolium (Oregon-grape or Oregon grape) is a species of flowering plant in the family Berberidaceae, native to western North America. It is an evergreen shrub growing to 1 m (3 ft) tall by 1.5 m (5 ft) wide, with pinnate leaves consisting of spiny leaflets, and dense clusters of yellow flowers in early spring, followed by dark bluish-black berries.
The common name is often, and always in the United Kingdom, left unhyphenated as "Oregon grape", though doing so invites confusion with the true grapes. Some authors avoid this confusion by using "Oregon grape-holly" or "Oregon holly-grape" as a vernacular name for any species of Mahonia. It is also occasionally printed as "Oregongrape".
Several common species of Oregon-grape are known, and many have numerous cultivars. Among these are tall Oregon grape (Mahonia aquifolium); Cascade, low, dull, or dwarf Oregon grape (M. nervosa); and creeping Oregon grape (M. repens).
Mahonia aquifolium grows to 1–2 m (3 ft 3 in–6 ft 7 in) tall by 1.5 m (5 ft) wide, with pinnate leaves up to 30 cm (12 in) long, each leaf made up of spiny leaflets. The leathery leaves resemble those of holly and the stems and twigs have a thickened, corky appearance. The flowers, borne in dense clusters in late spring, are yellow, and are followed by spherical dark dusty blue berries, which give rise to the common name "Oregon grape".
Some authors place Mahonia in the barberry genus, Berberis. The Oregon-grape is not related to true grapes, but gets its name from the purple clusters of berries whose color and slightly dusted appearance are reminiscent of grapes.
Mahonia 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 brushlands in the Cascades, Rockies, and northern Sierras.
Mahonia aquifolium is a popular subject in shady or woodland plantings. 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. Its berries attract birds.
The small purplish-black fruits, which are quite tart and contain large seeds, are included in smaller quantities in the traditional diets of Pacific Northwest aboriginal peoples, mixed with salal or another sweeter fruit. Today, they are sometimes used to make jelly, alone or mixed with salal. Oregon-grape juice can be fermented to make wine, similar to European barberry wine folk traditions, although it requires an unusually high amount of sugar. The inner bark of the larger stems and roots of Oregon-grape yields a yellow dye; the berries give purple dye. As the leaves of Oregon-grape are holly-like and resist wilting, the foliage is sometimes used by florists for greenery and a small gathering industry has been established in the Pacific Northwest.
- The Plant List
- Flora of North America vol 3
- "BSBI List 2007". Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-01-25. Retrieved 2014-10-17.
- RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 1-4053-3296-4.
- Harrison, Lorraine (2012). RHS Latin for gardeners. United Kingdom: Mitchell Beazley. p. 224. ISBN 978-1-84533-731-5.
- Michael P. Williams (2012). "Berberis aquifolium, in Jepson Flora Project (eds.) Jepson eFlora". Retrieved 2013-08-08.
- Flora of North America, vol 3
- Loconte, H., & J. R. Estes. 1989. Phylogenetic systematics of Berberidaceae and Ranunculales (Magnoliidae). Systematic Botany 14:565-579.
- Marroquín, Jorge S., & Joseph E. Laferrière. 1997. Transfer of specific and infraspecific taxa from Mahonia to Berberis. Journal of the Arizona-Nevada Academy of Science 30(1):53-55.
- Laferrière, Joseph E. 1997. Transfer of specific and infraspecific taxa from Mahonia to Berberis. Bot. Zhurn. 82(9):96-99.
- North Carolina Botanical Garden / Conservation / Plants to Avoid in the Southeastern United States
- Plants to Avoid in the Southeastern United States Tennessee Invasive Exotic Plant List
- "AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 62. Retrieved 25 March 2018.
- "RHS Plant Selector - Mahonia × wagneri 'Pinnacle'". Retrieved 13 April 2015.
- "RHS Plant Selector - Mahonia aquifolium 'Apollo'". Retrieved 13 April 2015.
- Pojar, Jim; MacKinnon, Andy, eds. (1994). Plants of Coastal British Columbia: including Washington, Oregon & Alaska, rev. ed. Vancouver: Lone Pine Publishing. p. 95. ISBN 978-1-55105-532-9.
- Henderson, Robert K. (2000). The Neighbourhood Forager. Toronto, Ontario: Key Porter Books. p. 111. ISBN 1-55263-306-3.
- Bliss, Anne (1993). North American Dye Plants, rev. and enl. ed. Loveland, Colorado: Interweave Press. p. 130. ISBN 0-934026-89-0.
- Hunn, Eugene S. (1990). Nch'i-Wana, "The Big River": Mid-Columbia Indians and Their Land. University of Washington Press. p. 352. ISBN 0-295-97119-3.
- Stermitz FR, Lorenz P, Tawara JN, Zenewicz LA, Lewis K (February 2000). "Synergy in a medicinal plant: antimicrobial action of berberine potentiated by 5'-methoxyhydnocarpin, a multidrug pump inhibitor". Proc. Natl. Acad. Sci. U.S.A. 97 (4): 1433–7. doi:10.1073/pnas.030540597. PMC 26451. PMID 10677479.
- "State Symbols: About the Oregon Grape". Oregon Blue Book. Oregon Secretary of State. 2018. Retrieved 1 January 2013.
|Wikimedia Commons has media related to Mahonia aquifolium.|
|Wikisource has original text related to this article:|
- The Oregon Grape in "Our State Flowers: The Floral Emblems Chosen by the Commonwealths", The National Geographic Magazine, XXXI (June 1917), pp. 481–517.
- Mahonia aquifolium images at bioimages.vanderbilt.edu
- Jepson eFlora (TJM2) treatment of Berberis aquifolium
- Calflora Database: Berberis aquifolium (Oregon grape, mountain grape)
- Flora of North America @ efloras.org: Berberis aquifolium — syn; formerly: Mahonia aquifolium
- UC Photos gallery: Berberis aquifolium
- Mountain Grape from Botanical.com