The name "cedar" is applied to species across at least four different botanical genera, creating considerable confusion in timber markets. Western red cedar (Thuja plicata) is a cypress-family conifer native to the Pacific Northwest of North America. Aromatic cedar (Juniperus virginiana) is a juniper from eastern North America. Spanish cedar (Cedrela odorata) is a hardwood in the mahogany family from Central and South America. True cedars (Cedrus species) - Atlas cedar, Cedar of Lebanon, and Deodar cedar - are native to the Mediterranean and Himalayan regions and are rarely available as commercial timber today, though historically significant. Despite their botanical differences, all share varying degrees of natural durability and aromatic properties that define the cedar market.
Western Red Cedar
Western red cedar (Thuja plicata) is the most commercially important cedar species globally, harvested primarily in British Columbia, Canada, and the US states of Washington, Oregon, and Idaho. Its density is exceptionally low at approximately 370 kg/m3 at 12% moisture content, making it one of the lightest commercially available softwoods. The Janka hardness is only 350 lbf (1,560 N) - soft enough to dent with a fingernail - but this low density conceals remarkable performance characteristics.
Western red cedar's natural durability comes from thujaplicins and other phenolic extractives concentrated in the heartwood. Under EN 350, the heartwood achieves Durability Class 2 (durable), resisting both fungal decay and termite attack without chemical treatment. In Australian Standards (AS 5604), it rates as Class 2 for above-ground decay and termite resistance. This natural durability, combined with a service life of 20 to 40 years for cladding in temperate climates, makes Western red cedar the dominant exterior cladding species in North America and an important export product.
The wood's thermal insulation value is roughly 20% higher than most softwoods due to its low density and cellular structure, contributing to its popularity in sauna construction and exterior wall cladding in Scandinavia, where it competes with locally produced spruce and pine. Western red cedar also exhibits negligible resin content, allowing it to accept a wide range of paints, stains, and penetrating oil finishes without the bleed-through problems associated with pine.
Aromatic Cedar and Moth-Repelling Properties
Eastern red cedar (Juniperus virginiana), traded as aromatic cedar, contains cedrol and cedrene in its heartwood oils at concentrations up to 3.5% by weight. These volatile organic compounds deter adult clothes moths (Tineola bisselliella) and carpet beetles, giving aromatic cedar its traditional role in chest and closet lining. The scent diminishes over time as the volatile oils evaporate, though sanding the surface refreshes it.
Despite marketing claims, scientific studies on cedar oil effectiveness as an insect repellent show mixed but generally positive results. Research published by the University of Kentucky entomology department confirmed that cedar oil vapours repel adult moths under confined conditions, though they do not kill eggs or larvae. For practical closet use, the recommendation is that cedar chest surfaces be lightly sanded every 3 to 5 years to expose fresh oil-bearing wood.
Aromatic cedar's mechanical properties are modest - density around 500 kg/m3, Janka hardness of 900 lbf (4,000 N) - but its fine texture, ease of working, and the striking contrast between its creamy sapwood and reddish-purple heartwood make it desirable for small decorative items, pencil making (the US pencil industry in Tennessee historically relied on eastern red cedar), and rustic furniture.
Spanish Cedar and True Cedars
Spanish cedar (Cedrela odorata), despite its name, is a hardwood related to mahogany. Its density averages 470 kg/m3, and its Janka hardness is approximately 600 lbf (2,670 N). The wood has a distinctive, long-lasting aromatic scent different from other cedars and is highly resistant to both decay and termite attack (Durability Class 2-3). Spanish cedar has been the traditional wood for cigar humidors and cigar box linings due to its aroma compatibility with tobacco, its ability to maintain stable humidity, and its insect resistance. It is also widely used for interior joinery and fine furniture in its native Latin American range, from Mexico to Argentina. CITES lists Cedrela odorata on Appendix II (effective 2020), requiring legal harvest verification for international trade.
True cedars (Cedrus atlantica from Morocco and Algeria, Cedrus libani from Lebanon and Turkey, Cedrus deodara from the Himalayas) are botanically distinct pines with highly aromatic, durable heartwood. Cedar of Lebanon (Cedrus libani) was the most prized timber of the ancient Mediterranean world, used in the construction of King Solomon's Temple in Jerusalem (circa 957 BCE), Egyptian pharaonic shipbuilding, and Phoenician maritime trade. Today, the natural range of all three Cedrus species is severely reduced, and commercial timber is essentially unavailable, with the wood reserved for conservation areas, ornamental plantings, and small-scale craft use.
Global Sourcing
British Columbia accounts for roughly 70% of global Western red cedar production, with Interfor, West Fraser, and Canfor among the major producers. The US-Japan softwood lumber trade, a fixture since the 1970s, saw Japanese demand for Canadian cedar for traditional post-and-beam homes drive a significant export market, though Japanese housing starts have declined from their 1990s peak. Chinese demand for cedar logs, primarily for processing into cladding re-exported to North America, has been a more recent development.
Aromatic cedar production is centred in the eastern United States, particularly Tennessee, Kentucky, and Arkansas, where it grows as a pioneer species on abandoned farmland. Spanish cedar is harvested from natural forests across its range, with Peru and Brazil as major exporters, though CITES listing has tightened supply chains and encouraged plantation development in several Latin American countries.