VALUE AND USE
SPECIES: Thuja plicata | Western Redcedar 



WOOD PRODUCTS VALUE : 
Western redcedar is an important commercial species throughout much of
its natural range [80].  In the Rocky Mountains, western redcedar
occupies some of the most productive sites, often producing stands with
high volume [26].  The wood is low in strength and soft but is very
resistant to decay, making it best suited for use as exposed building
material such as shingles, shakes, and exterior siding [57,69].
Hand-split western redcedar shakes sell for several times the price of
asphalt shingles but will last 100 years on a roof [8].  The wood is
fine and straight grained, which makes it suitable for interior
finishing [57].  Western redcedar wood is also used for utility poles,
fence posts, light construction pulp, clothes closets and chests, boats,
canoes, fish trap floats, caskets, crates, and boxes [50,80].


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Black-tailed deer browse western redcedar seedlings and saplings all
year long in British Columbia, and Rosevelt elk feed on them during the
fall, winter, and spring.  Western redcedar constitutes one of the most
important conifer foods of black-tailed deer in the Coastal forest
region of southern Vancouver Island [51].  Western redcedar was more
severely browsed than Douglas-fir (Pseudotsuga menziesii), western
hemlock, or Pacific silver fir (Abies amabilis) on the Olympic
Peninsula.  Western redcedar is a major winter food for big game in the
northern Rocky Mountains [51].  An analysis of 69 stomach samples
collected from elk harvested along the Lochsa and lower Selway rivers
between January 1 and April 1 from 1960 through 1970 showed that western
redcedar leaves made up 5 percent of the total winter diet by weight
[72].  In western Washington, black bears remove western redcedar bark
and feed on the exposed sapwood [50].

Cattle browse western redcedar in preference to Douglas-fir in
northwestern Oregon, and sheep damaged western redcedar reproduction
more than that of other trees in northern Idaho [51].  Seeds of this
conifer were only occasionally taken by field mice in caged tests [52].

Old-growth stands of western redcedar provide hiding and thermal cover
for several wildlife species.  Bears, raccoons, skunks, and other
animals use cavities in western redcedar for dens [8].  In the southern
Selkirk Mountains of northern Idaho, northeastern Washington, and
adjacent British Columbia, grizzly bears have been known to use heavily
timbered western redcedar and western hemlock forests [44].  Western
redcedar is used as nest trees by cavity nesting bird species such as
yellow-bellied sapsuckers, hairy woodpeckers, tree swallows, chestnut
backed chickadees, and Vaux's swifts [45,49].


PALATABILITY : 
NO-ENTRY


NUTRITIONAL VALUE : 
Relatively high concentrations of calcium and low concentrations of
nitrogen are nearly always present in western redcedar foliage.
Phosphorous concentrations are usually low [51].


COVER VALUE : 
NO-ENTRY


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Western redcedar can be planted on disturbed sites within its natural
range.  The erosion-control potential and long-term revegetation
potential of western redcedar have been rated as medium [13].  Western
redcedar may be the species of choice for reforesting high, brush-risk
areas near the coast [50].  It is suitable for planting on slightly dry
to wet nutrient-poor to nutrient-rich sites [commonly with Douglas-fir,
Sitka spruce (Picea sitchensis), Alaska-cedar (Chamaecyparis
nootkatensis), or western hemlock].  Western redcedar does best when
planted in mineral soils on upland sites and in well-decomposed organic
material on lowland sites [38].  Containerized western redcedar appears
to perform somewhat better than bareroot stock [26].  Direct seeding is
practical and effective where a mineral soil seedbed is available.
Methods for collecting, storing, and planting western redcedar seeds and
seedlings have been detailed [50,51,69].


OTHER USES AND VALUES : 
Perfumes, insecticides, medicinal preparations, veterinary soaps, shoe
polishes, and deodorants are made from western redcedar leaf oil.
Western redcedar extractives and residues are used in lead refining,
boiler-water additives, and glue extenders [50].  Western redcedar was
an extremely valuable tree to the Indians of the Northwest Coast,
providing materials for their shelters, clothing, dugout canoes, and
fishing nets [8,76].  Northwest Coast Indians shredded the inner layer
of bark so finely that it could be used for diapers and cradle padding
[8].

Western redcedar's drooping branches, thin fibrous bark, and flat sprays
of scalelike leaves make it an attractive ornamental.  When properly
trimmed western redcedar is an excellent hedge [8,41].


MANAGEMENT CONSIDERATIONS : 
Insects and disease:  Western redcedar is a host for several
economically important insect species.  One of the most important is the
gall midge (Mayetiola thujae), which sometimes seriously damages western
redcedar seeds in Oregon, Washington, and British Columbia [50].
Seedlings are occasionally damaged by weevils (Steremnius carenatus) in
British Columbia, and large trees are killed by bark beetles
(Phloeosinus sequoiae) on poor sites in southeastern Alaska.  The
western redcedar borer (Trachykele blondeli) causes degradation
resulting in cull of sawtimber [50].

More than 200 fungi are found on western redcedar.  A leaf blight
(Didymascella thujina) infects second- and third-year nursery seedlings.
As much as 97 percent of the natural western redcedar regeneration may
be killed when this blight reaches epidemic proportions.  The most
important fungi attacking western redcedar are root butt and trunk rots.
Poria asiatiaa and P. albipellucida are the most important trunk rots
near the coast; P. asiatioa and Phellinus weiri are the most important
in the interior range.  Rots are most evident in old stands [50].

Animal damage:  Seedlings and saplings are often severely browsed by
deer, elk, and rodents.  Browse damage may be one of the most important
stand establishment problems [50].  Grazing by cattle in burned stands
in the western redcedar/queencup beadlily (Clintonia uniflora) habitat
type in southwestern Montana retards establishment of western redcedar
[36].

Other damaging agents:  Western redcedar is often windthrown in wet
environments, but it is windfirm on dry sites [50,51].  Western redcedar
is damaged by salt spray [50].  It is also sensitive to atmospheric
pollution.  Clay dust from a brick works in British Columbia produced a
columnar form in nearby western redcedars [51].

Silvicultural considerations:  Care must be exercised when logging sites
dominated by western redcedar due to the high water table.  Bottomland
sites should not be disturbed other than to salvage high-value trees or
to remove high-risk trees.  If harvested some dead and down logs should
be left to serve as a seedbed for western redcedar and western hemlock
regeneration.  Extensive disturbance of these sites could cause
irreparable damage [13].

Western redcedar should be grown in pure stands when saw-timber,
shingles, or shakes are the desired products.  Even-aged mixtures of
western redcedar and other conifers will be harvested either too early
for the western redcedar sawtimber or too late for the other conifers
when mixed-species, even-aged stands are clearcut.  Western redcedar can
be grown in mixed stands when poles are to be produced under even-aged
management regimes.  A nearly closed canopy should be maintained at all
times.  Open-grown western redcedar tend to develop poor form, excessive
limbs, and multiple tops [51].  Western redcedar is perhaps the most
valuable species for which uneven-aged systems are applicable in the
highly productive western redcedar and western hemlock habitat types of
the Inland West [26].

Response to release:  Because western redcedar is shade tolerant, it
should be treated to minimize shock from release through slow or timely
thinning treatments.  Western redcedar's ability to respond to release
varies with tree, stand, and site conditions.  An 80-year-old western
redcedar stand, with the overstory removed and thinned, responded with
increased growth rates up to 5 years after treatment.  However, 5 to 10
years after release, growth rates slowed, and root diseases became
apparent [26].  Releasing western redcedar saplings slowly over a 17
year period had good results.  The saplings responded favorably to
release with increased growth rates and a gradual increase in vigor.
Thinning western redcedar stands should occur prior to age 30.  Spacing
of 1 foot by 1 foot (0.3 by 0.3 m) is appropriate for most young stands.
This density provides good tree and stand development and retains the
options for future intermediate treatments [25,26].

Related categories for Species: Thuja plicata | Western Redcedar