Synonyms: Eastern White Cedar, Northern White Cedar, Arborvitae, Swamp Cedar
Scientific Name: Thuja occidentalis L.
Family: Cupressaceae (Cypress Family)
Eastern North America
Essential oil containing thujone and camphor, flavonoids, sesquiterpenes, polysaccharides.
Who would have thought that the thick garden hedge that protects our privacy not only keeps out prying eyes but also has potent medicinal properties? The dense, evergreen arborvitae can reach a height of up to 30 meters and can be trimmed into any shape desired. Because of its scale-like leaves it looks like a conifer from the distance, an impression reinforced by the smooth cone-like, yellowish-brown fruits sitting on the tips of the branches. The fruits clearly distinguish Thuja occidentalis from the related species Thuja orientalis which has winged fruits. The separate male (catkins) and female (yellowish-green, star-shaped) flowers appear in April to May. Pollination is brought about by the wind. The tips of the leaves contain special glands in which the plant stores essential oil. If you rub a leaf between your fingers the oil is released and you can smell its pungent odour. Thuja likes moist, cool soils and, under optimal conditions, it can become 400 years old.
The shoot tips of the arborvitae are used medicinally. The essential oil contained in them has antiviral action and stimulates the immune system. However, the correct dosage is important. In high concentrations thujone, the main constituent of the oil, irritates the skin and can lead to cramps and bleeding of the internal mucous membranes.
It has been employed as an embrocation for the treatment of rheumatism. As homeopathic remedy Thuja occidentalis is used for treatment of rheumatism, colds, skin rashes and neuralgia. An essence is effective for treatment of warts.
The name arborvitae, tree of life, probably comes from the tree's evergreen leaves which make it appear full of life even in winter and which were regarded as a symbol of life in many cultures. The scientific name Thuja is derived from the Greek thyon meaning to sacrifice and refers to the burning of Thuja wood for ritual purposes which used to be practiced in ancient times. The epithet occidentalis means western and refers to the western origin of this species.
In its native America the Indians used the sturdy, durable wood of the arborvitae to build houses and boats. The young branches were used to prepare ointments for treatment of joint pain. The drug was also used internally as diaphoretic (substance that stimulates sweating) and diuretic (substance that stimulates urine production), and for the treatment of syphilis, worms, rheumatism and scurvy. It was because of this last use that European seafarers in the mid-16th century were in the habit of taking arborvitae with them on their return voyage.
In Europe arborvitae was planted as a symbol of life at the birth of a child, a wedding or the establishment of a village. If the tree grew vigorously this was considered a positive sign. Its use as a cemetery tree symbolizes the longing for eternal life. Because of its toxic, organ-damaging properties
arborvitae used to be employed as an abortifacient which did, however, also put the mother's life at risk.
The plant from another perspective
At first sight the arborvitae appears to have a dry quality, being characterized by firm, hard leaves and compact fruits. A closer look reveals a strong affinity to water. It prefers damp, swampy sites and the chopped up leaves are surprisingly slimy. Its predominant characteristic is thus coolness. This does not seem to go with the tree's high essential oil content, as essential oils are usually associated more with a fiery, warm character. However, the arborvitae does not combine with the essential oils but puts them away in separate glands. In its coolness it forms the fire. This typical characteristic could be regarded as the model for the medicinal action of arborvitae.