''Calocedrus decurrens'', with the common names incense cedar and California incense-cedar
(syn. ''Libocedrus decurrens'' Torr.), is a
species of
conifer
Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...
ous tree native to western North America. It is the most widely known species in the genus, and is often simply called 'incense cedar' without the regional qualifier.
[Farjon, A. (2005). ''Monograph of Cupressaceae and Sciadopitys''. Royal Botanic Gardens, Kew. ]
Description
''Calocedrus decurrens'' is a large tree, typically reaching heights of and a trunk diameter of up to . The largest known tree, located in
Klamath National Forest,
Siskiyou County, California, is tall with a circumference trunk and a spread.
Specimens form a broad conic crown of spreading branches. The
bark
Bark may refer to:
* Bark (botany), an outer layer of a woody plant such as a tree or stick
* Bark (sound), a vocalization of some animals (which is commonly the dog)
Places
* Bark, Germany
* Bark, Warmian-Masurian Voivodeship, Poland
Arts, ...
is orange-brown weathering grayish, smooth at first, becoming fissured and exfoliating in long strips on the lower trunk on old trees.
Specimens can live to over 500 years old.
The foliage is produced in flattened sprays with scale-like
leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
long; they are arranged in opposite
decussate
Decussation is used in biological contexts to describe a crossing (due to the shape of the Roman numeral for ten, an uppercase 'X' (), ). In Latin anatomical terms, the form is used, e.g. .
Similarly, the anatomical term chiasma is named aft ...
pairs, with the successive pairs closely then distantly spaced, so forming apparent whorls of four; the facial pairs are flat, with the lateral pairs folded over their bases. The leaves are bright green on both sides of the shoots, with only inconspicuous
stoma
In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bor ...
ta.
The foliage, when crushed, gives off an aroma somewhat akin to shoe-polish.
The
seed cones are long, pale green to yellow, with four (rarely six) scales arranged in opposite decussate pairs; the outer pair of scales each bears two winged
seeds, the inner pair(s) usually being sterile and fused together in a flat plate. The cones turn orange to yellow-brown when mature about 8 months after pollination. The pollen cones are long.
Distribution
The bulk of the tree's range is in the United States, from central-southwestern
Oregon through most of
California and the extreme west of
Nevada, as well as a short distance into northwest Mexico in northern
Baja California.
It grows at altitudes of .
Ecology
At lower elevations, associated trees include oaks and
ponderosa pine.
Giant sequoia bears similarities to the species, but has sharp leaves. In the south–southwest U.S. some have confused bushy
juniper
Junipers are coniferous trees and shrubs in the genus ''Juniperus'' () of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere, from the Arcti ...
s for incense cedar.
With its thick basal bark,
the incense cedar is one of the most fire- and drought-tolerant plants in California. Although the tree is killed by hot, stand-replacing crown fire, it spreads rapidly after lower-intensity burns. This has given the incense cedar a competitive advantage over other species such as the
bigcone Douglas-fir in recent years. Incense cedar is more
shade tolerant than
Douglas-fir, but not as much so as
grand or
white fir. It grows slowly when needed to outlast competition.
This tree is the preferred host of a
wood wasp, ''
Syntexis libocedrii'' a species which lays its eggs in the smoldering wood immediately after a forest fire.
The tree is also host to incense-cedar mistletoe (''
Phoradendron libocedri''), a
parasitic plant which can often be found hanging from its branches. Fire scars provide an entry point for ''Tyromyces amarus'' (pocket dry rot).
''
Gymnosporangium'' rust disease afflicts the trees, but is rarely fatal.
For numerous birds during the wintertime, ''Calocedrus decurrens'' has been seen to be used for
foraging.
According to the
United States Department of Agriculture, in areas of the Western Sierra Nevada in California, numerous species of birds are thought to use the incense cedar as a "foraging substrate" so that they can attain as much food as needed.
Human impacts on these trees due to forest management practices have caused issues for many of these birds, threatening the use of the incense cedar as a forage substrate.
Uses
The wood is soft and light, and has a pleasant odor and is generally resistant to rot. It has been used for external house siding, interior paneling, and to make moth-resistant
hope chests.
It was once the primary material for wooden
pencils, because it is soft and tends to sharpen easily without forming splinters.
Native Americans
Indigenous peoples of California use the plant in traditional medicine,
basket making,
hunting bows, building materials, and to produce fire by friction. A Northern California tribe used branchlets to filter out sand from water when leaching toxins from acorn meal; foliage also served as a flavoring.
The
Maidu Concow tribe name for the plant is hö'-tä (
Konkow language).
Cultivation
''Calocedrus decurrens'' is cultivated as an
ornamental tree
Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that i ...
, for planting in gardens and parks. It is used in traditional,
xeriscapic,
native plant, and
wildlife gardens; and also in designed
natural landscaping and
habitat restoration projects in California. It is valued for its columnar form and evergreen foliage textures.
The tree is also grown in gardens and parks in cool summer climates, including the
Pacific Northwest in the
Northwestern United States and
British Columbia, eastern Great Britain and continental
Northern Europe
The northern region of Europe has several definitions. A restrictive definition may describe Northern Europe as being roughly north of the southern coast of the Baltic Sea, which is about 54th parallel north, 54°N, or may be based on other g ...
. In these areas it can develop an especially narrow columnar crown, an unexplained consequence of the cooler climatic conditions that is rare in trees within its warm summer natural range in the
California Floristic Province. Other cultivated species from the family
Cupressaceae
Cupressaceae is a conifer family, the cypress family, with worldwide distribution. The family includes 27–30 genera (17 monotypic), which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdio ...
can have similar crown forms.
[Mitchell, A. F. (1996). ''Alan Mitchell's Trees of Britain''. Collins .]
Award of Garden Merit
This plant has gained the
Royal Horticultural Society's
Award of Garden Merit
The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions.
History
The Award of Garden Merit ...
, and has the cultivar 'Berrima Gold'.
Essential oils
Various species in the family Cupressaceae can be utilized for the creation of
essential oil
An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the o ...
s.
Scientific studies have shown that these essential oils have "strong antimicrobial properties."
Antimicrobial properties are those properties of a substance that lower the levels of microbes, such as
bacteria and
viruses. These antimicrobial properties could potentially be used for therapies in developing countries, although more testing and
clinical trials should be done before such measures are implemented.
See also
*
Cedar wood
*
List of California native plants
*
Gallery
Calocedrus decurrens copa.jpg, Adult specimen
Calocedrus decurrens Incense Cedar.jpg, Tree in McMinnville, Oregon
Incense Cedar in Lassen VNP.jpg, Trunks in Lassen Volcanic National Park, California
Calocedrus decurrens MHNT.BOT.2004.0.810.jpg, Cones and seeds
Calocedrus decurrens 7976.jpg, Foliage and pollen cones
Calocedrus decurrens 7947.jpg, Opened cones
Calocedrus decurrens (young female cones).jpg, Young female cones
Calocedrus decurrens_CL_MHNT.jpg , Section of wood
References
External links
*
*
*
{{Taxonbar, from=Q1399164
decurrens
Least concern plants
Trees of Baja California
Trees of the Northwestern United States
Trees of the Southwestern United States
Flora of California
Flora of Oregon
Flora of the Cascade Range
Flora of the Klamath Mountains
Flora of the Sierra Nevada (United States)
Natural history of the California Coast Ranges
Natural history of the Peninsular Ranges
Natural history of the Transverse Ranges
Plants used in traditional Native American medicine
Least concern flora of North America
Least concern flora of the United States