Botanical Name: Mahonia pumila
Species: M. pumila
Common Names: Dwarf Barberry
Habitat: Mahonia pumila is native to South-western N. America – California and southern Oregon. It grows on mountains. Open woods and rocky areas at elevations of 300 – 1200 metres.
Mahonia pumila is an evergreen shrub growing 10 – 40cm tall. The plant suckers at the base, producing a cluster of unbranched stems. Stems monomorphic, without short axillary shoots. Bark of 2d-year stems gray-brown or purplish, glabrous. Bud scales 3-6 mm, deciduous. Spines absent. Leaves 3-9-foliolate; petioles 0.5-4 cm. Leaflet blades thick and rigid; surfaces abaxially dull, papillose, adaxially dull, glaucous; terminal leaflet stalked, at least on most leaves, blade 4-8 × 2-5 cm, 1.3-1.9 times as long as wide; lateral leaflet blades ovate to oblong-ovate or elliptic, 1(-3)-veined from base, base obtuse, rarely truncate, margins plane or undulate, toothed, with 2-10 teeth 1-3 mm tipped with spines to 1.6-3 – 0.3-0.4(-0.5) mm, apex obtuse or rounded, rarely broadly acuminate. Inflorescences racemose, dense, 30-45-flowered, 2-4 cm; bracteoles membranous, apex rounded or obtuse, sometimes apiculate. Flowers: anther filaments with distal pair of recurved lateral teeth. Berries dark blue, glaucous, oblong-ovoid to spheric, 5-8 mm, juicy, solid. 2n = 28.
The plant is harvested from the wild for local use as a food and a medicine. It is sometimes grown as an ornamental, where it can be used as a ground cover.
Mahonia pumila is hardy to about -15°c if growing in a sheltered position.
An easily grown plant, it thrives in any good well-drained garden soil, preferring one on the dryish side. Prefers a sunny position, but also succeeds in the light shade of trees.
Established plants sucker freely and form quite dense thickets Resistant to honey fungus.
Some Berberis/Mahonia species (especially Berberis vulgaris) harbour the black stem-rust fungus (Puccinia graminis Persoon). This is a major disease of wheat and barley crops and can spread from infected barberries to the grain crop. The sale or transport of susceptible or untested species of Berberis is illegal in the United States and Canada This species is resistant to infection by the fungus.
Fruits are eaten – raw or cooked. We have seen no reports of edibility for this species, but it is certainly not poisonous. The fruit is likely to have an acid flavour and be suitable for making jams. jellies etc. The fruit is about 10mm in diameter.
A decoction of the roots is used as a blood tonic and as a treatment for coughs.
Mahonia species have a long history of medicinal usage, with several members of the genus being commonly used in traditional medicine and also in modern herbalism. They are employed in the treatment of a wide range of conditions and have, in particular, been demonstrated to exert good efficacy in the clinical treatment of dysentery, internal and external haemorrhage, acne vulgaris and chronic pharyngitis amongst other diseases. Phytochemical research into this genus has resulted in the identification of more than 150 chemical constituents, amongst which alkaloids are predominant. The isolated compounds and crude extracts have been shown to exhibit a wide spectrum of in vitro and in vivo pharmacological effects, including antimicrobial, anti-inflammatory, hepatoprotective, antioxidant, antimutagenic and analgesic properties.
Berberine, an alkaloid that is universally present in the rhizomes and stems of Mahonia species, has been shown to have a marked antibacterial effect. and is also used as a bitter tonic. Since it is not appreciably absorbed by the body, it can be used orally in the treatment of various enteric infections, especially bacterial dysentery
Berberine has also shown antitumour activity.
The plant should not be used with Glycyrrhiza species (Liquorice) because this nullifies the effects of the berberine.
Agroforestry Uses: This species forms suckers freely and should make a good dense ground cover in a sunny position.
A yellow dye is obtained from the inner bark of the stem and roots It is green.
Dark green, violet and dark blue-purple dyes are obtained from the fruit. A green dye is obtained from the leaves.
All parts of the plant contain the alkaloid berberine – this is most concentrated in the roots, stems and inner bark, and least concentrated in the fruits. In small quantities berberine has a range of effective medicinal applications but, in excess, can cause vomiting, lowered blood pressure, reduced heart rate, lethargy, and other ill-effects.
The fruit of most, if not all, members of this genus are more or less edible and can be eaten in quantity since the levels of berberine in the fruit are very low.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.