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: Wax Tree

General Information

Toxicodendron succedaneum is a deciduous shrub or small tree usually growing up to 7 metres tall with occasional specimens to 15 metres. The bole can be up to 50cm in diameter[].
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 cultivated in China, Taiwan, Vietnam and Japan for its wax and varnish[]. The tree is also harvested from the wild for local use as a medicine and source of various materials.
Toxicodendron succedaneum has a very wide distribution, a large population, is not currently experiencing any major threats and no significant future threats have been identified. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2018)[].

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[].
The leaves contain the ubiquitous carcinogen shikimic acid[].

Botanical References

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Range

E. Asia - southeastern China, Japan, Korea, India, Pakistan, Nepal, Bangladesh, Myanmar, Thailand, Cambodia, Laos, Vietnam, Indonesia.

Habitat

Forests and shrubberies; at elevations up to 2,400 metres in the Himalayas[]. Lowland and hill forests, lowland thickets on limestone; at elevations from 100 - 1,500 metres, occasionally to 2,500 metres[].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	9.00 m
Pollinators	Bees
Self-fertile	No
Cultivation Status	Cultivated, Wild

Cultivation Details

Toxicodendron succedaneum is a plant of the warm temperate to tropical zones of eastern Asia and is not very cold-hardy, only succeeding outdoors in the milder areas of the temperate zone[, ]. Another report gives a hardiness rating of 5 - if correct then this would mean that the plant can tolerate winter temperatures falling to around -25°c, at least for short periods[]. The young growth in spring can be damaged by late frosts.
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[].
This species is frequently cultivated in Japan for its sap and the wax obtained from its fruit[].
Many of the species in this genus, including this one, are highly toxic and can also cause severe irritation to the skin of some people, whilst other species are not poisonous. It is relatively simple to distinguish which is which, the poisonous species have axillary panicles and smooth fruits whilst non-poisonous species have compound terminal panicles and fruits covered with acid crimson hairs[, ]. The toxic species are sometimes separated into their own genus, Toxicodendron, by some botanists[].
Dioecious. Male and female plants must be grown if seed is required.

Edible Uses

Fruit[]. The acid pulp is eaten[, ]. The edible fruit contains ellagic acid[]. These reports need to be treated with some caution due to the general toxicity of the species[].

Medicinal

The plant is antidote, antivinous, cholagogue, febrifuge, ophthalmic. It is used as a wash to counteract varnish poisoning[]. Use with extreme caution, see notes above on toxicity.

The fruit is used in the treatment of phthisis[].
A wax from the fruits is used in ointments[].

An ethanolic extract of the leaves exhibits anticancer and antiviral activities[].

Other Uses

The leaves contain about 20% tannin[]. They can be collected as they fall in the autumn and used as a brown dye or as a mordant[].

The resinous sap is tapped and used as a varnish and lacquer[, , , , , , ]. It is much used in Japanese art and needs to be kept in a cool humid place for it to dry properly. The Japanese traditionally kept their paintings in a damp cave until the lacquer had dried.

A yellow dye is obtained from the wood[].

A pure white wax obtained from the fruit is used to make candles, floor wax, varnish etc[, , , , , , , ]. The fruit contains about 17% wax[]. The fatty acid composition of the wax is 77% palmitic, 5% stearic and arachidic, 6% dibasic, 12% oleic and a trace of linoleic[]. The asymmetrical drupe is around 7 - 10mm in diameter with a thick, white, waxy mesocarp[].

A wax obtained from the fruit is used as an ingredient in commercial cosmetic preparations as an emollient, binding agent and viscosity controller[].

The seed oil contains 25% glycerides of palmitic, 47% oleic and 28% linoleic[].

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[].