Western Red Cedar Thuja plicata Donn ex D. Don

silhouetteDescription: Large to very large tree with tapering trunk, buttressed at base, and with a narrow, conical crown of short, spreading branches drooping at ends. Foliage is resinous and aromatic.

Height: 30-55m or more.

Diameter: 0.6-2.5m or more.

Leaves: evergreen; opposite in 4 rows; 1.5-3mm long. Scalelike, short-pointed; side pair keeled, flat pair usually without gland-dot; shiny dark green, usually with whitish marks beneath.

Bark: reddish-brown, thin, fibrous, and shreddy.

Twigs: much branched in horizontal plane, slightly flattened in fanlike sprays, jointed.

Flowers: Male cones ovoid, 1-2 mm, shedding pollen in early spring.

Cones: 12mm long; clustered and upright from short, curved stalk; elliptical, brown; with 10-12 paired, thin, leathery, sharp-pointed cone-scales; 6 usually bearing 2-3 seeds with 2 wings; mature in the summer of the first year.

Habitat: Moist, slightly acid soils; forming widespread forests with Western Hemlock (Tsuga heterophylla), also with other conifers. Because of its tolerance of anaerobic soil conditions, it also occurs on waterlogged 'Muskeg' sites where few other plants can grow. In California (its southern limit) it is found in the North Coastal Conifer Forest (m10) plant community.

range mapRange: SE Alaska southeast along coast to NW California; also SE British Colombia south in Rocky Mountains to W Montana; to 900m in north; to 2100m in south.

The wood is light, pale and aromatic. Easily worked and relatively durable, it is particularly resistant to rot. It is the commonest timber used for greenhouses and conservatories. Indians of the Northeast coast carved their famous totem poles and split lumber for their lodges from this durable softwood. The name "Canoe-cedar" refers to the special war-canoes hollowed out of giant trunks, although the wood is also among the best for the construction of "cedar strip" kayaks and canoes using modern technology and encapsulated in fibreglass and epoxy resin. Indians also used the wood for boxes, batons and helmets and the fibrous inner bark for rope, roof thatching, blankets and cloaks. Stands of Western Red Cedar were decimated in the early twentieth century when it was practically the only source of wood for telegraph poles and railway sleepers. The largest Western Red Cedar is 6.4m in diameter, ranking second only to Sequoiadendron in North American native trees; however, this species is not among the tallest. Discovered by the Malaspina expedition, and described from a specimen collected by Taddæus Hænkel. First introduced to Britain in 1853. Specimens from this first planting are reaching 40+m and up to 6m circumference in the early 1980s.

Information: Audubon (1980), Lawrence (1985), Bean III & Supp.

Source: Weasdale Nurseries, Newbiggin-on-Lune, Cumbria.

Purchased: Five at 24-36" from Weasdale 1993.11.19

Planted: 1993.12.18 a pair (at B39B) and a single tree (later moved to B47C) in US strip, Pacific Northwest Temperate Rainforest zone. One as a screen at front of side strip (where it is intended that it will be kept pruned rather than grown as a specimen).

Progress: The taller of the two planted as a pair had its leader snapped off by strong winds during 1998, but doesn't seem to be suffering otherwise. It had reached 2.75 m by 1998.10.07. The smaller of this pair seems to have become shaded out and there was no trace of it on 2004.09.27 when the bigger tree was measured as 6.1m. The tree which had to be moved didn't seem to take much of a performance hit, and was at 2.2 m in 1998, and 6.0 m in 2004.

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