header photo

Kinnikinnick Native Plant Society

Focusing on native plants and conservation in North Idaho

Oregon Grape 
Majonia repens

Original Species paper by Lois Wythe 

"Oregon Grape," says Botanist Underhill, "is rather like the prophet—unsung in his own country."  Common in this area, it is often overlooked these days, but not so among the  Indians and colonists, and it appeared in all the pharmacopoeias until the late 1880’s.  The Scottish botanist David Douglas, who roamed around here in the 1830's, identified it very quickly as a fine ornamental shrub.  

There are more than 100 species of Mahonia, says HORTUS THIRD; and since there are some 500 species of Berberis, taxonomists finally decided to move it into its own genus  - Mahonias.  However, many seed catalogs, and even some states like Idaho, still classify it under Berberis, so here's another plant you may need to check out in more than one index.  The name comes from Bernard M'mahon, a distinguished early American horticulturist who died in 1816. 

In North Idaho we have three native Mahonias, the most common being actually the least attractive, Mahonia repens. The Oregon state flower is Mahonia aquifolium, a small shrub in contrast to our low-growing Creeping Mahonia.  A third plant Mahonia nervosa, quite rarely seen now. Betsy Hammet has seen it only rarely where she found it in hemlock/cedar woods in the French Creek drainage up the Pack River .  

It's difficult to mistake this striking evergreen plant. The flowers are small, bright yellow, with six petals, nine sepals, six stamens, in 1 to 3 inch racemes in dense clusters.  Leaves are from 4 to 6 inches long, and difference in the three species are evident in sketches. They are dark green and lustrous in spring and summer, turning to bronze, gold, crimson and purple in fall.



The fruit (it is NOT a grape) is deep blue and purple clusters of berries!  While not tasty to humans, they are certainly edible. Our M. repens is a ground-hugger, while the other varieties may reach 3 to 6 feet and are much more shrub-like. The berries are best made up as a tart jelly to use as a meat accompaniment. Crushed and made up into a drink they are sometimes used by herbalists to cool fevers. The berries are also high in Vitamin C and were often used to treat scurvy. However, it is the rootstock's healing qualities which were so prized by the Indians who crushed and dried the yellow roots to cure a wide variety of ailments like ulcers, heartburn, rheumatism, kidney problems, and some skin conditions. The early settlers learned about this root's amazing medical properties in the 1800's and Oregon grape tonics were a popular market commodity.  Herbalists recommended soaking the roots in warm beer to relieve hemorrhaging


The active ingredient that makes Oregon grape such an effective remedy is well known to us today.  It is an alkaloid called berberine (which powerful healing constituent is found also in goldenseal).  Berberine stimulates bile secretions and modern herbalists and homeopaths believe it promotes good liver function and purifies the blood. Most herbal manuals recommend steeping an ounce of dried root in a cup of tolling water, with a dosage of 3 tbsp. daily, although they warn that persons with over active livers should stay away from this root.


Landscape uses: Because they are so adaptable and so hardy, all of the Mahonias recommend themselves to home landscape use. Many hybrids have been developed too, to take advantage of the holly-like aspect of the shrub varieties in particular. Our M. repens, the creeping variety, is a fine ground cover.  It is at its very best in partial sun and fairly moist conditions and will tolerate considerable traffic when fully established. Great for edges like driveways and paths.  In the Arboretum we are edging many of our paths with Oregon grape. And it isn't fussy about soil types, either.  If you are going to transplant pieces of established plants, this will be done most successfully in the very early spring before the new spring growth starts—as early as the snow is gone.  If transplanting from an area of deep shade into a sunnier spot, do it gradually.


Wildlife: Fruit-eating birds and animals will eat the berries and the shrubs provide shelter for both.  Note: Deer seldom browse this plant.


Pests and diseases:  leaf spot, powdery mildew and rust can be damaging. Good air circulation seems to be the best preventive, but planting at the proper time seems to be a beneficial influence, too. Spring is better than fall.


Other uses:  And if you have ever seen objects made of warm-toned Oregon grape, polished carefully, you will always remember it. Crucifixes are often made of this wood. Beautiful yellow and tan dyes are also made from the roots, and even from the stems and leaves. The fruit yields a purplish-blue color to wool if mordanted with alum.