Blooms March through May
Perennial, temperate areas worldwide
Sometimes called Mahonia, Barberry is sometimes only one foot in height, sometimes up to 10 feet, and depending on the species, can be either evergreen or deciduous. It comes in various shapes and sizes, from tight little shrubs to sparse and vine-like. The alternate, ovate to lance-shaped leaves are often compared to holly, being thick, somewhat leathery, and shiny, and generally barbed, or spine-toothed, along the margins. The leaves themselves may be simple or compound--again, depending on the species--with from 3 to 11 leaflets. Leaves turn bright red in response to age, shade, or frost. Flowers are most often bright yellow clusters but some of the 600 or so species of Barberry may sport white flowers on their racemes. The flowers give way to deep blue-black or bright red berries. The wood is often yellow, as well as the pith, the coloration due to the high content of berberine, the plant's most active chemical. But berberine is highest in the rhizomes. This and the root may be so high in berberine content that they are almost bright orange. Identifying this shrub as a Barberry is not as difficult as it may seem--there is a basic look about them all, regardless of flower or berry color or general size and shape.
Medicinally, all Barberry (formerly Mahonia) species are used in much the same way. The roots or rhizomes are used because of the high berberine content, although the bark and berries are also used. And in some species the leaves are used. The yellow color is the key. If the pith and/or bark are yellow high berberine content is indicated.
In June (1999) clinical testing proved that Mahonia aquifolium, also known as Oregon Grape Root, was effective in the treatment of psoriasis. Health Canada has now approved a topical cream containing the root extract for the treatment of psoriasis and other skin conditions. But long before double-blind clinical testing was invented, Native Americans and other indigenous peoples knew of the plant's properties. In fact, all Barberry species were used to treat wounds, eczema, and all manner of skin problems. Berberine has strong anti-microbial and fungicidal properties, aside from being particularly astringent and anti-inflammatory. It is said to make a good eyewash.
Internally, Barberry has long been used to stimulate bile secretion and the liver in general, as a bitter digestive tonic, diuretic, alterative, and immunostimulant. The roots and berries have refrigerant properties, so can be used as a febrifuge or a cool summer drink, respectively. As it turns out, Barberry is a substitute for goldenseal, which is so overharvested that it has become, or is becoming, endangered. And for those with hypertension, Barberry seems the better choice (if the species in question is not also endangered) because it has vasodilatory properties, whereas goldenseal constricts the veins. Other warnings attach themselves to Barberry: large doses can cause nausea, vomiting, constriction of the bronchial tubes, hazardous drops in blood pressure, heart rate, and breathing. This is a plant that would most definitely be off-limits to pregnant women and, of course, to those who do not know how to use it.
The berries of all the species were used as food in one way or another--either eaten fresh, or made into preserves or pounded into cakes to save for later use. The berries of Berberis pinnata were used by a southern California tribe for painting arrows. The Spaniards carved up the yellow roots for crucifixes. And the roots were used to make a bright yellow dye.