Eastern red cedar
Meaning of Eastern red cedar: A North American juniper, not a true cedar, whose fragrant wood yields the oil sold as cedarwood.
Definition of Eastern red cedar
Eastern red cedar is a common North American evergreen, Juniperus virginiana, belonging to the cypress family. Despite the name it is a juniper rather than a true cedar. Its dense aromatic heartwood is used for furniture, fence posts and storage chests, and steam distillation of that wood produces cedarwood oil, which is used in soaps, perfumes and insect repellents.
Why is the name misleading?
True cedars belong to the genus Cedrus and grow in the mountains of the Mediterranean and the Himalayas. This tree is a juniper in the cypress family, and several other unrelated fragrant softwoods share the label as well. The confusion carries into product names, so an oil sold as cedarwood may come from any of several species with different chemical makeups. Anyone matching a product to a published safety report has to check the botanical name rather than the common one.
What is the oil used for?
| Use | Notes |
|---|---|
| Fragrance | Soaps, colognes, household products |
| Insect repellent | The traditional basis of cedar chests and closet blocks |
| Aromatherapy | Used for a calming effect, with limited supporting evidence |
| Microscopy | An older use as an immersion oil on lenses |
Does it have medical effects?
The oil has demonstrated activity against insects and against some microbes in laboratory conditions, which supports the storage chest tradition. Claims about hair growth, anxiety and infection in people rest on very little evidence. Its main documented significance in medicine runs the other way. Concentrated essential oils are toxic if swallowed, and they can burn skin when applied undiluted. Like tea tree oil and other volatile plant oils, it is a recognized cause of contact dermatitis in susceptible people, and skin already inflamed absorbs more of it.
What about the pollen?
Junipers of this group release large quantities of wind-borne pollen in late winter, an unusual season for pollen allergy, and they are a well recognized trigger for allergic rhinitis across much of the central and southern United States. A closely related species is responsible for the intense seasonal reaction known regionally as cedar fever. The wood dust generated by cutting and sanding is also a respiratory irritant, and occupational exposure among woodworkers has been linked with asthma and with nasal symptoms. Pollen counts for these trees can be extremely high on dry windy days, and the grains travel long distances, so symptoms occur well away from any visible tree.
Also known as
Used in a sentence
Skin testing was positive for eastern red cedar pollen, matching the seasonal pattern of symptoms.
Good to know
The tree is a juniper rather than a true cedar, so oils labeled cedarwood vary in botanical source and composition, and its winter pollen is a recognized cause of allergic rhinitis.