FAMILY: Cupressaceae
SYNONYMS: Swamp cedar, white cedar, northern white cedar, eastern white cedar, tree of life, American arborvitae, cedarleaf (oil).
GENERAL DESCRIPTION: A graceful pyramid-shaped coniferous tree up to 20 metres high with scale-like leaves and broadly-winged seeds, sometimes planted as hedging. The tree must be at least fifteen years old before it is ready to be used for essential oil production.
DISTRIBUTION: Native to north eastern North America; cultivated in France. The oil is produced mainly in Canada and the USA, similar oils are also produced in the East – see here.
OTHER SPECIES: There are many forms and cultivated varieties of this tree: the western red cedar or Washington cedar (T. plicata); the Chinese or Japanese cedar (T. orientalis or Biota orientalis); the North African variety (T. articulata) which yields a resin known as ‘sanderac’.
The hiba tree (Thujopsis dolobrata) is used to produce hiba wood oil and hiba leaf oil in Japan. Hiba wood oil, according to available data, is non-toxic, non-irritant and non-sensitizing (unlike the other thuja oils), and has excellent resistance to fungi and bacteria due to the ketonic substances found in the oil. It is used extensively in Japan as an industrial perfume.
HERBAL/FOLK TRADITION: Used as an incense by ancient civilizations for ritual purposes. A decoction of leaves has been used for coughs, fever, intestinal parasites, cystitis and venereal diseases. The ointment has been used for rheumatism, gout, warts, verrucae, psoriasis and other ailments.
The twigs are current in the British Herbal Pharmacopoeia, used specifically for bronchitis with cardiac weakness, and warts.
ACTIONS: Antirheumatic, astringent, diuretic, emmenagogue, expectorant, insect repellent, rubefacient, stimulant (nerve, uterus and heart muscles), tonic, vermifuge.
EXTRACTION: Essential oil by steam distillation from the fresh leaves, twigs and bark.
CHARACTERISTICS: A colourless to pale yellowy-green liquid with a sharp, fresh, camphoraceous odour.
PRINCIPAL CONSTITUENTS: Thujone (approx. 60 per cent), fenchone, camphor, sabinene and pinene, among others.
SAFETY DATA: Oral toxin – poisonous due to high thujone content. Abortifacient.
AROMATHERAPY/HOME: USE None. ‘Should not be used in aromatherapy either internally or externally.’.
OTHER USES: Used in pharmaceutical products such as disinfectants and sprays; also as a counter-irritant in analgesic ointments and liniments. A fragrance component in some toiletries and perfumes. Employed as a flavour ingredient in most major food categories (provided that the finished food is recognized thujone-free).