Common Name: Amur Cork Tree

General Information

Phellodendron amurense is a deciduous tree with a rounded, broad-spreading crown; it can grow from 10 - 16 metres tall. The bole is usually short, with loe, horizontal branching that can dip to touch the ground The tree has a deeply fissured, corky bark[, , ].
A popular and commonly used herbal medicine in eastern Asia, where the tree is harvested from the wild and also often cultivated and traded. The plant has also been grown in the past for the yellow dye obtained from its bark, and is often grown as an ornamental.
This tree has escaped cultivation in parts of the northeastern U.S.A., where it is somewhat aggressively spreading into some native hardwood forest areas[]..

Known Hazards

The bark contains berberine, a bitter-tasting alkaloid which, in small quantities, has a range of effective medicinal applications but, in excess, can cause vomiting, lowered blood pressure, reduced heart rate, lethargy, and other ill-effects.

Botanical References

, ,

Range

E. Asia - Russian Far East, eastern China, Japan, Korea, Vietnam

Habitat

Forests in valleys and on mountains[]. Montane forests and thickets, river valleys[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	12.00 m
Self-fertile	No
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Phellodendron amurense is a very cold-hardy plant, being able to tolerate temperatures down to around -30°c or more when fully dormant. The young growth is much more tender, however, and is liable to damage from late spring frosts. The plant grows best in areas with long hot summers, which allow it to fully ripen its wood and make it more tolerant of winter cold[, , ].
Prefers a moisture retentive well-drained deep rich loam in full sun[, ]. Prefers a neutral to alkaline soil[]. Succeeds in shallow chalky soils[]. Plants are gross feeders and require a rich soil if they are to perform well[]. The plant grows well in cities, being tolerant of many urban air pollutants[].
The leaves are aromatic[]. The foliage and fruits are unpleasantly aromatic when bruised[],
This species is occasionally cultivated fo its use as a dye and a medicine in Asia[, ] and also for timber in S.E. Europe[].
A dioecious species - both male and female forms must be grown if fruit and seed are required.

Edible Uses

Fruit[, ]. The globose fruit is about 1cm in diameter and has a strong scent of turpentine[, ].

Medicinal

Amur cork tree, called Huang Bai in China, is commonly used in Chinese herbalism, where it is considered to be one of the 50 fundamental herbs, but one that should be used with care[, ]. A strongly bitter remedy, the bark acts strongly on the kidneys and is regarded as a detoxicant for hot damp conditions[].
Huang Bai should only be used under professional supervision and should not be take during pregnancy according to one report[], whilst another says that it is the 'poor man's cure-all' being employed both externally and internally as a treatment for almost every ailment[].

The bark is alterative, antibacterial, antirheumatic, aphrodisiac, bitter stomachic, cholagogue, diuretic, expectorant, febrifuge, hypoglycaemic, ophthalmic, resolvent, skin, vasodilator, vulnerary and tonic[, , , , , , , , ]. It is taken internally in the treatment of acute diarrhoea, dysentery, jaundice, vaginal infections including Trichomonas, acute urinary tract infections, enteritis, boils, abscesses, night sweats and inflammatory skin diseases[, , ]. It is commonly used in conjunction with Scutellaria baicalensis and Coptis chinensis in a preparation called 'injection of three yellow herbs'[]. It is given intramuscularly for upper respiratory tract infections[].
The plant is applied topically in the treatment of skin conditions and injuries such as eczema, pustules, scalds and burns[]. Apoultice is applied in the treatment of furunculosis and wounds[].
The bark of 10 year old trees is harvested in the winter or spring and dried for later use[, ].

The fruit is expectorant[].

The bark contains around 0.6% of the alkaloid 'berberine', which is known to have a marked antibacterial effect, and also the compounds palmatine. obakunone, obakulactone and sterols[, , ].

Recent research has shown that the bark is useful in the treatment of meningitis and conjunctivitis[].

Other Uses

A yellow dye is obtained from the inner bark[]. An effective dye for silk[].

The bark is used as an ingredient in commercial cosmetic preparations as an abrasive and a tonic[].
An extract of the bark is used as an ingredient in commercial cosmetic preparations as a skin conditioner and tonic[].

An oil obtained from the seed has insecticidal properties similar to pyrethrum[].

Wood - heavy, hard, strong, close grained. Used for furniture[].
The bark is a cork substitute[].

Propagation

Seed - best sown in the autumn in a cold frame[]. Stored seed requires 2 months cold stratification, sow in late winter in a cold frame[, ]. Germination is usually good. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the cold frame for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Cuttings of half-ripe wood, 7 - 10cm with a heel, mid summer in a frame. Pot up in autumn and over winter in a cold frame. Fair to good percentage[].
Root cuttings - obtain in December and store in leafmold in a warm place for 3 weeks. Cut into 4cm lengths and plant horizontally in pots. Grow on in a warm greenhouse. Good percentage[].