Oregon Grape, Cascade barberry

Mahonia nervosa

Physical Characteristics

Mahonia nervosa is an evergreen Shrub growing to 0.6 m (2ft) by 1 m (3ft 3in) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 6. It is in leaf all year, in flower from February to April. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay and nutritionally poor soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It prefers dry or moist soil.

Distribution

North-western N. America.

Habitats

Woodland Garden Sunny Edge; Dappled Shade; Shady Edge; not Deep Shade; Ground Cover;

Edible Uses

Edible Parts: Fruit Leaves Edible Uses: Fruit - raw or cooked[2, 3, 101]. An acid flavour but it is rather nice raw, especially when added to muesli or porridge[K]. Unfortunately, there is relatively little flesh and a lot of seeds[K]. Too acid for most tastes but they are very good in jams, jellies, pies etc[183]. They can also be used to enhance the flavour of bland fruits or made into a refreshing lemon-flavoured drink[183]. The fruit is about 8mm in diameter[200]. Young tender leaves - cooked. Simmered in a small amount of water and eaten as a snack[183].

Medicinal Uses

Antiarthritic Antibacterial Antitumor Blood tonic Dysentery Laxative Tonic The root is alterative and tonic[4]. It improves the digestion and absorption and is recommended in the treatment of psoriasis, syphilis and impure blood conditions[4, 257]. A decoction of the peeled and chopped root bark has been used as a wash in treating arthritis and as an eyewash for red itchy eyes[257]. The fruit is an excellent safe and gentle laxative[257]. Berberine, universally present in rhizomes of Mahonia species, has marked antibacterial effects[218] and is used as a bitter tonic[213]. Since it is not appreciably absorbed by the body, it is used orally in the treatment of various enteric infections, especially bacterial dysentery[218]. It should not be used with Glycyrrhiza species (Liquorice) because this nullifies the effects of the berberine[218]. Berberine has also shown antitumour activity[218]. The root and root bark are best harvested in the autumn[213].

Known Hazards

None known