This paper reviews the characteristics of western red cedar, with particular emphasis on its use in utility poles. Western red cedar naturally grows primarily in British Columbia, Alaska, Washington, Oregon, California, Idaho and Montana. Compared to other commercial softwoods it has low density, increased corrosivity, weaker mechanical properties, high dimensional stability, and high natural durability. The natural decay and termite resistance of western red cedar’s heartwood is due to the presence of extractives. These include thujaplicins and a series of lignans, the most abundant of which is plicatic acid. The role of these extractives in the durability of wood in service is still not fully understood. The natural durability of western red cedar heartwood increases from the pith to the heartwood/sapwood boundary and from the top of the tree to the base. Although younger trees are being harvested today than in previous years, the wood produced today remains durable. Approximately 155,000 WRC utility poles are produced annually in the United States and Canada. Most of these are pressure-treated with preservatives to maximize service life. However, thermal treatments of the full-length of the pole, or of just the butt, may also be used.

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