Western Red Cedar (Thuja plicata)

Medicinal uses: collect in summer/fall from young trees—highest oil content, antifungal, antibacterial—stimulates phagocytosis, helps athlete's foot, ringworm, jock itch, nail fungus, chronic vaginitis, stimulates smooth muscle—helps with respiratory, urinary tract, and reproductive system problems, can make tea, tincture, cold infusion, steam

Internal uses include: boiling limbs to make a tuberculosis treatment, chewing leaf buds for sore lungs, boiling leaves to make a cough remedy, making a decoction of leaves to treat colds, chewing leaf buds to relieve toothache pain, making an infusion to treat stomach pain and diarrhea, chewing the inner bark of a small tree to bring about delayed menstruation, making a bark infusion to treat kidney complaints, making an infusion of the seeds to treat fever using a weak infusion internally to treat rheumatism and arthritis

External uses include: making a decoction of leaves to treat rheumatism, washing with an infusion of twigs to treat venereal disease, including the human papilloma virus and other sexually transmitted diseases, making a poultice of boughs or oil to treat rheumatism, making a poultice of boughs or oil to threat bronchitis, making a poultice or oil from inner bark to treat skin diseases, including topical fungal infections and warts, using shredded bark to cauterize and bind wounds. Extracts of red cedar have been shown to have antibacterial properties against common bacteria. Compounds with antifungal properties have also been isolated.

Preparations:Most preparations of red cedar call for boiling the medicinal parts to make a decoction or for making a tea or infusion. Little information exists on dosages. An essential oil can be prepared from red cedar. This oil is meant to be used topically. It is toxic if taken internally, and has the ability to produce convulsions or even death if taken in even small quantities. A 1999 study done in Switzerland noted an increase in poisoning deaths from plant products, including Thuja, due possibly to an increase in people practicing herbal healing and aromatherapy.

Precautions:As noted above, the oil of all species of thuja can cause convulsions. Decoctions of the bark of red cedar can also cause miscarriage. Therefore, pregnant women should not use red cedar.

Side Effects:Many people develop asthma and bronchial spasms from exposure to red cedar or red cedar dust. This is due to an allergic reaction to plicatic acid present in the wood. Red cedar induced asthma is a serious occupational hazard to loggers in western North America.

Interactions:There are no studies and little observational evidence to indicate whether red cedar interacts with other herbs or with Western pharmaceuticals.

Pacific Northwest Medicinal Plant Guide (Check out all plants growing in Tryon Farm's medicinal garden!)