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| ## western red cedar {#western-red-cedar .Title-Header}               |
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| *Thuja plicata* Donn ex D. Don                                        |
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| Plant Symbol = THPL                                                   |
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Contributed by: USDA NRCS National Plant Data Center & the Biota of
North America Program

### ![](media/image2.jpeg){width="2.595833333333333in" height="1.9152777777777779in"}

## Alternate Names 

Giant arborvitae, western arborvitae, giant red-cedar, Pacific
red-cedar, shinglewood, canoe cedar

## Uses

*Industry*: The wood of western red cedar is primarily used in roofing
for shingles and shakes, because of its attractive appearance,
durability, lightness, and superior insulation qualities. It is also
used in exterior finishings, utility poles, fence posts, piling, paper
pulp, and various types of containers. The species is managed for timber
in Europe and New Zealand. Cedar leaf oil is often the basis for
production of perfumes, insecticides, medicinal preparations, veterinary
soaps, shoe polishes, and deodorants.

*Wildlife*: The leaves of western red cedar are a major winter food for
big game in the northern Rocky Mountains, and deer browse it all year
along the coast. Many cultivars are grown for ornament, including those
used for hedges. It is the provincial tree of British Columbia.

*Ethnobotanic*: Western red cedar has been called "the cornerstone of
northwest coast Indian culture" and the large-scale use of its wood and
bark delineates the cultural boundary of the northwest coast peoples
within its range. Wood served for house planks, house posts, roof
boards, various kinds of boxes, and canoes. It is easy to split and was
often used for bentwood boxes. Bark was made into skirts, capes, and
complete dresses for women, and roots and limbs were used for baskets
and rope. The inner bark was used for slow matches to carry the fire
from camp to camp, and also as mats, and baskets. Various medicines were
derived from the tree.

## Status

Please consult the PLANTS Web site and your State Department of Natural
Resources for this plant's current status, such as, state noxious status
and wetland indicator values.

## Description

*General*: Cypress family (Cupressaceae). Native trees growing to 50
(-75) meters tall, often buttressed at base, with a conical to irregular
crown, old individuals frequently with many leaders and many dead spike
tops; branches arching, branchlets pendent, flattened, in fan-shaped
sprays; bark gray to reddish-brown, 10-25 mm thick, fibrous, separated
into flat, connected ridges. Leaves are evergreen, scale-like and
sharply pointed, (1-) 3-6 mm long, opposite in alternating pairs (in 4
rows), glossy green above, white-striped on the lower surface, with a
spicy fragrance when crushed. Seed cones are ellipsoid, 10-14 mm long,
brown; seeds 8-14 per cone, 4-7.5 mm long, with lateral wings about as
wide as the body. The common name pertains to the western distribution
and cedar-like appearance.

*Variation within the species*: although small inter-populational
differences have been documented, western red-cedar seems to show less
within-species genetic variation than other northwestern conifers.
Horticultural varieties with color and growth form differences have been
developed (*atrovirens*, *fastigiata*, *pendula*).

*Distribution*: The range of western red-cedar is essentially in two
segments: a Coast Range-Cascade Range segment from southeastern Alaska
to northwestern California and a Rocky Mountain segment from British
Columbia and Alberta to Idaho and Montana. For current distribution,
please consult the Plant Profile page for this species on the PLANTS Web
site.

## Adaptation 

The trees occur on various substrates, commonly on moist sites (swamps,
wet ravines, poorly drained depressions), but on a variety of landforms,
including rocky slopes, at 0-1500 (-2300) meters elevation. They usually
occur in mixed coniferous forests, rarely in pure stands. In
cultivation, they prefer moist, acid, well-drained soils but have been
grown in heavy clays of the Midwest.

## Establishment

Cone production begins in open-grown trees of western red cedar at about
10-20 years of age but peak production occurs after 70-80 years and may
continue for several centuries. Good seed crops are produced at
intervals of 2-3 years.

In clearcuts and other disturbed areas, seedlings account for most of
the western red-cedar regeneration, but seedlings in mature stands may
be less abundant than individuals produced by vegetative reproduction
from layering, rooting of fallen branches, and branch development on
fallen trees. Disturbed mineral soil seems to be a major requirement for
regeneration from seed. Unburned soil provides better seedbed than
scorched soil, but slash burning may create mineral soil surfaces in
cut-over areas. In mature stands of western red cedar, rotten wood in
contact with the soil provides an effective seedbed. Partial shade,
which lowers evaporation and soil temperature, is beneficial to seedling
growth.

Western red cedar is often present in pioneer, seral, and climax stages
of forest succession. Vegetative regeneration may be predominant in
ecologically stable communities, but wide seed distribution allows it to
invade disturbed areas. It is highly shade-tolerant and is well suited
for reforesting high brush-risk areas near the coast.

Age determination of western red-cedar is complicated by buttress
formation and the associated complex growth patterns, but ring counts of
trees from Washington and British Columbia indicate that some trees live
at least up to 1460 years.

## Management

In mixed-species and uneven-aged stands, western red cedars tolerate
shady understory conditions and can maintain slow but acceptable growth
rates over long periods. In timber harvest of these mixed-species
stands, most of these trees are taken by clearcutting. Because of steep
terrain, decay, and breakage, harvesting costs are high and lumber
recovery is low. Because of its high susceptibility to windthrow in wet
environments and in the moist sites where growth and yield are highest,
western red cedars should not be left as scattered seed trees. Even
those along clearcut margins may be lost to wind throw or exposure.

Severe browse damage to western red-cedar seedlings and saplings by
deer, elk, and rodents may be the most important problem in the
establishment of young stands. In near-coastal sites, western red-cedar
is more severely damaged by fire than any of its associates.

## Cultivars, Improved and Selected Materials (and area of origin)

These plant materials are readily available from commercial sources.
Contact your local Natural Resources Conservation Service (formerly Soil
Conservation Service) office for more information. Look in the phone
book under "United States Government." The Natural Resources
Conservation Service will be listed under the subheading "Department of
Agriculture."

## References

Chambers, K.L. 1993. *Thuja*. Pp. 410-411, IN: *Flora of North America,
north of Mexico*. Vol. 2, *Pteridophytes and gymnosperms*. Oxford Univ.
Press, New York, New York.
\<http://hua.huh.harvard.edu/cgi-bin/Flora/flora.pl?FLORA_ID=12395\>

Gunther, E. 1945. *Ethnobotany of western Washington*. Univ. Washington
Publ. Anthropol. 10(1):1-62.

Minore, D. 1990. *Thuja plicata*. Pp. 590-600, IN: R.M. Burns and B.H.
Honkala. *Silvics of North America*. *Volume 1.* *Conifers*. USDA,
Forest Service Agric. Handbook 654, Washington, D.C.
\<http://willow.ncfes.umn.edu/silvics_manual/Table_of_contents.htm\>

Stewart, H. 1984. *Cedar: Tree of life to the Northwest Coast Indians*.
Douglas & McIntyre, Vancouver.

## Prepared By

*Guy Nesom*

Formerly BONAP, North Carolina Botanical Garden, University of North
Carolina, Chapel Hill, North Carolina

## Species Coordinator

*M. Kat Anderson*

USDA, NRCS, National Plant Data Center, c/o Plant Sciences Dept., Davis,
California

Edited: 19jun02 jsp; 04jun03 ahv; 060818 jsp

For more information about this and other plants, please contact your
local NRCS field office or Conservation District, and visit the PLANTS
Web site\<[http://plants.usda.gov](http://plants.usda.gov/)\> or the
Plant Materials Program Web site
\<[http://Plant-Materials.nrcs.usda.gov](http://Plant-Materials.nrcs.usda.gov/)\>

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large print, audiotape, etc.) should contact USDA\'s [TARGET
Center](http://www.usda.gov/oo/target.htm) at 202-720-2600 (voice and
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*To file a complaint of discrimination write USDA, Director, Office of
Civil Rights, Room 326-W, Whitten Building, 14th and Independence
Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964 (voice or
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*Read about [Civil Rights at the Natural Resources Convervation
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