
Toxicodendron wallichii
Toxicodendron wallichii
Safety & 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[1]. 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[2].
Cultivation Details
Toxicodendron wallichii is not a very cold-hardy plant, being able to tolerate short-lived temperatures falling down to around -10°c when fully dormant. The young growth in spring, however, is more sensitive and 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[3, 4]. Plants have brittle branches and these can be broken off in strong winds[4]. Plants are also susceptible to coral spot fungus[3]. Plants in this genus are notably resistant to honey fungus[4]. 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[5, 6]. The toxic species are sometimes separated into their own genus, Toxicodendron, by some botanists[4]. A dioecious species - both male and female forms must be grown if fruit and seed are required.
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[4]. The stored seed also needs hot water treatment and can be sown in early spring in a cold frame[4]. 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[4]. Root cuttings 4cm long taken in December and potted up vertically in a greenhouse. Good percentage[7, 4]. Suckers in late autumn to winter[4]. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Toxicodendron+wallichii>
Pollinators
Bees
References
- [1]Illustrated Flora of North Central Texas — Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J · Botanical Research Institute, Texas. · 1999 · http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm · ISBN 1-889878-01-4 ↩︎An excellent flora, which is also available on-line.
- [2]Fire Effects Information System — http://www.feis-crs.org/feis/ ↩︎An on-line information site with comprehensive information on over 1,100 species of plant. Mainly developed to supply information on the effects of fire on plants and animals, it also contains a wealth of other information on the plants
- [3]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [4]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [5]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [6]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
- [7]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
- [8]Flora of China — Missouri Botanical Garden Press; St. Louis. · 1994 · http://flora.huh.harvard.edu/china/ ↩︎An excellent, comprehensive resource in 25 volumes. In addition to the botanical information the flora also gives basic information on habitat and some uses. An on-line version is also available.
- [9]New Trees — Grimshaw J.; Bayton R.; Wilks H. · Kew Publishing; London · 2009 · ISBN 1842461737 ↩︎Provides comprehensive botanical descriptions and horticultural commentary on over 800 tree species that have been introduced to cultivation in recent decades.
- [10]Flowers of the Himalayas. — Polunin. O. and Stainton. A. · Oxford Universtiy Press · 1984 · ISBN - ↩︎A very readable and good pocket guide (if you have a very large pocket!) to many of the wild plants in the Himalayas. Gives many examples of plant uses.
- [11]Plants and People of Nepal — Manandhar. N. P. · Timber Press. Oregon. · 2002 · ISBN 0-88192-527-6 ↩︎Excellent book, covering over 1,500 species of useful plants from Nepal together with information on the geography and peoples of Nepal. Good descriptions of the plants with terse notes on their uses.
- [12]Glossary of Indian Medicinal Plants (Including the Supplement). — Chopra. R. N., Nayar. S. L. and Chopra. I. C. · Council of Scientific and Industrial Research, New Delhi. · 1986 · ISBN - ↩︎Very terse details of medicinal uses of plants with a wide range of references and details of research into the plants chemistry. Not for the casual reader.
- [13]A Weavers Garden — Buchanan. R. · McGraw-Hill Contemporary · 1987 · ISBN 0934026289 ↩︎Covers all aspects of growing your own clothes, from fibre plants to dyes.
- [14]Forest Flora of Chakrata, Dehra Dun and Saharanpur. — Gupta. B. L. · Forest Research Institute Press · 1945 · ISBN - ↩︎A good flora for the middle Himalayan forests, sparsly illustrated. Not really for the casual reader.
- [15]A Dictionary of Plants Used by Man. — Usher. G. · Constable · 1974 · ISBN 0094579202 ↩︎Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
- [16]A Manual of Indian Timbers. — Gamble. J. S. · Bishen Singh Mahendra Pal Singh · 1972 · ISBN - ↩︎First written in the 19th century, but still a classic, giving a lot of information on the uses and habitats of Indian trees. Not for the casual reader.
- [PFAF]Plants for a Future — pfaf.org ↩︎