There has been considerable uncertainty amongst botanists as to the best way of treating the genus Toxicodendron, with some viewing it as a genus distinct from Rhus, whilst others see insufficient differences and lump the two genera under Rhus. Toxicodendron is treated here as distinct, with two of the major differences from a gardener’s viewpoint being that Toxicodendron has a toxic sap (not toxic in Rhus) and the fruits have a thick, waxy mesocarp.

Common Name: Lacquer Tree

General Information

Toxicodendron vernicifluum is a deciduous tree of erect, slender habit when young[ it can grow up to 20 metres tall[].
This is one of the primary species of Toxicodendron that is harvested on a commercial basis for its sap - this is used to make a varnish that is widely employed in Oriental artwork. The plant is both cultivated and also harvested from the wild for this purpose. The tree also yields an oil and a wax and has a range of medicinal applications.

Known Hazards

Species in the genus Toxicodendron are known to contain resinous phenolic compounds known as urushiols that can cause severe skin problems in humans. Direct contacr with the plant, exposure to smoke or fumes from a burning plant or even contact with pets, animals or cothing that have touched the plant can cause severe allergic dermatitis in some individuals. There is usually a latent period of about 12 - 24 hours from the moment of contact, this is followed by a reddening and severe blistering of the skin. Even plant specimens 100 or more years old have been known to cause problems[].
The plant does not cause skin problems with wildlife or livestock - the foliage and fruits are eaten by several other species of animals and birds - though some pets are sensitive to it[].

Botanical References

, ,

Range

E. Asia - northern Pakistan, northern India, Nepal, China, Japan.

Habitat

Woods and thickets on mountain slopes; at elevations from 800 - 2,800 metres[, ]

Properties

Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	15.00 m
Pollinators	Bees
Self-fertile	No
Cultivation Status	Wild

Cultivation Details

Toxicodendron vernicifluum is not very cold tolerant according to one report that says it is only hardy into zone 9 (tolerating only occasional light frosts to about -5°c)[] but there are large healthy trees at Cambridge and Edinburgh Botanical gardens (Zone 7, with winter temperatures that can fall below -15°c), and both sites had fruiting trees 12 metres or more tall in September 1989[].
Species in this genus generally succeed in a well-drained fertile or moderately fertile soil in full sun or light shade[, ].
Plants have brittle branches and these can be broken off in strong winds[]. Plants are also susceptible to coral spot fungus[]. Plants in this genus are notably resistant to honey fungus[].
Cultivated for its lacquer in the warmer areas of Japan[, ].
Partly a dioecious species - both male and female forms must be grown if fruit and seed are required.

Edible Uses

None known

Medicinal

The leaves are used in the treatment of wasting diseases and internal parasites[].

The seed is haemostatic and is used in the treatment of dysentery[, ].

A resin (the sap?) from the plant is emmenagogue, haemolytic, stimulant, tonic and vermifuge[, ]. It is used in the treatment of coughs, intestinal worms, amenorrhoea, and ecchymoses[]..

Some caution is advised in the use of the leaves and stems of this plant, see the notes above on toxicity.

Other Uses

A non-drying oil is obtained from the fruit and is used in making candles[, , , , , ]. The fruit contains about 25% fat[]. The fruit is crushed, heated and then crushed to extract the oil[]. The oil attains a tallow-like consistency on standing and is used to make candles. These burn brilliantly, though they emit a pungent smoke[]. The symmetrical drupe is around 5 - 6mm x 7 - 8mm with a thick, waxy mesocarp[].

The sap can be used as a varnish or a lacquer. It is obtained by incision of the stem[, , , , , ], which is best done in mid-summer[]. The lacquer is frequently used in Japanese art, it requires a damp atmosphere in which to dry and harden, a moist cave being ideal[]. It is resistant to acids, alkalis, alcohol and temperatures up to 70°c[].

A wax obtained from the fruit is used as an ingredient in commercial cosmetic preparations as an emollient and stabilizer[].
An extract of the plant is used as an ingredient in commercial cosmetic preparations as an antioxidant and skin conditioner[].
An extract of the bark is used as an ingredient in commercial cosmetic preparations as an antioxidant, astringent, skin protector and bleaching agent[].

The leaves and galls formed as a result of insect damage are rich in tannin[]. The leaves can be collected as they fall in the autumn and used as a brown dye or as a mordant[].

Propagation

Seed - best sown in a cold frame as soon as it is ripe. Pre-soak the seed for 24 hours in hot water (starting at a temperature of 80 - 90c and allowing it to cool) prior to sowing in order to leach out any germination inhibitors[]. The stored seed also needs hot water treatment and can be sown in early spring in a cold frame[]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse 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, 10cm with a heel, mid summer in a frame[].
Root cuttings 4cm long taken in December and potted up vertically in a greenhouse. Good percentage[, ].
Suckers in late autumn to winter[].