THUJA (Thuja spp. – Cupressaceae)

Thuja is a genus of five hardy, evergreen coniferous trees and shrubs native to North America and Canada (T. occidentalis, white cedar, and T. plicata, Western red cedar), Japan (T. standishiz), China (T. orientalis) and Korea (T. koraiensis). The white cedar was the first American tree to be grown in France: it was introduced in 1526 from Canada and grew in the royal gardens at Fontainebleau.

The trees are cypress-like, and most are small and slow growing with the exception of the Western red cedar. The scale-like leaves are pressed closely to the stem, the flowers – both male and female on the same tree – are small and terminal and the cones are small with scales and winged seeds. The foliage of all types, excepting only T. orientalis, are strongly aromatic, exuding an odour without being crushed and noticeable from several yards away.
The name thuja (or thuya in French) is a Latinized form of a Greek word meaning to fumigate, or thuo to sacrifice. Theophrastus described how trees of the genus were grown in ancient times in Cyrene near the temple of jupiter-Ammon, and parts were burned in religious ceremonies to venerate the gods. The bark was often used to sculpt religious objects and statues. Another name for the tree is arbor-vitae, tree of life.

The American Indians used thuja, making the leaves and bark into a poultice for rheumatic joints and, because of the sudorific properties, decoctions to drink for virus infections.
Samuel Hahnemann (1755 -1843), the father of homoeopathy, introduced the plant’s medicinal properties to Europe, where it was used as a tincture. In Germany in 1875, doctors Mohnike and Brecher wrote a paper about the remarkable healing powers of thuja, particularly in cases of skin excrescences and tumours. They noted how quickly the skin repaired and healed itself after a twice-daily application of the tincture; the skin became pale and dry, inflammation reduced, and the tumours disappeared. Later, Dr Leclerc prescribed it for warts, skin abnormalities and as a stimulant of the urinary system because of the stimulant constituents (a-pinene, fenone and d-thujone).


Description: Thuja plicata, or Western red cedar, is the variety recommended for its medicinal properties. The leafy young twigs, freshly cut and dried, are the parts used for distillation. There is more essential oil present in spring, very little in summer.
The principal constituents: a-pinene, borneol, bornyl acetate, d-thujone, fenchone and fenone. The properties of thuja oil are antirheumatic and antiseptic. Dangers: I do not recommend the use of thuja essential oil in self treatment. It should only be used by a reputable practitioner as thujone is a dangerous constituent whether taken in large or small dosages. It should never be taken internally, and if precautions are not taken, even external application can be very toxic.


In illness
In the hands of a professional aromatherapist Thuja essential oil gives very good results in treatment of psoriasis of the scalp, skin excres¬cences, skin rashes, and alopecia. Thuja can also be a remarkable ally in the fight against the bad abscesses of acne, and severe infection.

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