04 Feb What Tree? Western Red Cedar
Western Red Cedar (Thuja plicata)
Our focus this month is on the western red cedar, a majestic evergreen conifer native to the Pacific northwest of North America. This impressive species can reach heights of over 60m and can live for hundreds of years – there are some specimens which are well over 1,000 years old.
As evidenced by its Latin name thuja plicata, the western red cedar is not a true cedar, but is the largest in the genus thuja, part of the cypress family. Its species name plicata means ‘braided’, referencing the pattern seen in its leaves. These flat sprays of evergreen foliage seemingly emerge without any obviously visible buds, earning the tree the label ‘arborvitae’ or ‘tree of life’, and it has been revered as such for centuries. Many First Nations and tribal communities consider it central to their cultural identity, using nearly every part of the tree for shelter, tools, ceremonial objects, clothing and in cooking or curing food.
In the UK the western red cedar is mainly planted for its timber which is highly durable. It contains a natural preservative which is resistant to fungal attack, making it ideal for outdoor construction such as posts, decking or shingles.
Appearance and Identification
The leaves of the western red cedar grow in flat sprays of opposing pairs, sprouting all along the twigs. They are only 2-3mm long and dark glossy green from above with white markings on their underside. When they are crushed they emit a warm, sweet/spicy smell reminiscent of pineapple or pear drops.
Flattened sprays of foliage
The bark is richly coloured, ranging from cinnamon to reddish-brown and is arranged in vertical strips. These can be peeled away in narrow, fibrous ribbons.
Bark of Western Red Cedar
The species is monoecious with small, inconspicuous male flowering cones. The female flowering cones are found on the tips of the branches and are reddish-purple in colour. The seeds are ovate with narrow wings on either side, held in slender oval-shaped woody cones.
Propagation and Control
Thriving in the mild, wet climates of coastal rainforests, western red cedar typically flourishes in deep, well-drained soils with ample moisture. It also grows in mixed conifer forests further inland, where it benefits from the cooler conditions of river valleys and mountainsides. While it can tolerate shade in its early stages, the tree generally reaches its most impressive heights in partially open areas with consistent moisture.
The western red cedar is generally a hardy species but can be susceptible to root rots such as phytophthora if growing in heavily shaded or waterlogged conditions. Changes in temperature due to climate change may also increase the incidence of cedar leaf blight.
Source and Reference Materials
Information detailed in this post has been obtained from the author’s own knowledge and photographic library where possible. Additional source of information and photographs include:
Van den Berk, B.V. (2004). Van den Berk on Trees. Van den Berk Nurseries.