''Calocedrus decurrens'', with the common names incense cedar and California incense cedar (syn. ''Libocedrus decurrens'' Torr.), is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

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 sin ...

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 up to . The largest known tree, located in

Klamath National Forest Klamath National Forest is a United States National Forest, national forest, in the Klamath Mountains and Cascade Range, located in Siskiyou County, California, Siskiyou County in northern California, but with a tiny extension (1.5 percent of th ...

Siskiyou County, California Siskiyou County ( ) is a county (United States), county located in the northwestern portion of the U.S. state of California. As of the 2020 United States census, 2020 census, the population was 44,076. Its county seat is Yreka, California, Yre ...

, is tall with a circumference trunk and a spread. Specimens form a broad conic crown of spreading branches. The

bark Bark may refer to: Common meanings * 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) Arts and entertainment * ''Bark'' (Jefferson Airplane album), ...

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 (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

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 (: stomata, from Greek language, Greek ''στόμα'', "mouth"), also called a stomate (: stomates), is a pore found in the Epidermis (botany), epidermis of leaves, stems, and other organs, that controls the rate of gas exc ...

ta. The foliage, when crushed, gives off an aroma somewhat akin to shoe-polish. The

seed cones A conifer cone, or in formal botanical usage a strobilus, : strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads. They are usually woody and variously conic, cylindrical, ovoid, to globular, and have scales ...

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

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s, 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 Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

through most of

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and the extreme west of

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

, as well as a short distance into northwest Mexico in northern

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

. It grows at altitudes of .

Ecology

At lower elevations, associated trees include oaks and

ponderosa pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine, is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is t ...

Giant sequoia ''Sequoiadendron giganteum'' (also known as the giant sequoia, giant redwood, Sierra redwood or Wellingtonia) is a species of coniferous tree, classified in the family Cupressaceae in the subfamily Sequoioideae. Giant sequoia specimens are the la ...

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 as far south ...

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 ''Pseudotsuga macrocarpa'', commonly called the bigcone spruce or bigcone Douglas-fir, is an evergreen conifer native to the mountains of southern California. It is notable for having the largest (by far) conifer cone, cones in the genus ''Pseud ...

in recent years. Incense cedar is more

shade tolerant In ecology, shade tolerance is a plant's ability to tolerate low light levels. The term is also used in horticulture and landscaping, although in this context its use is sometimes imprecise, especially in labeling of plants for sale in nursery (ho ...

than

Douglas-fir The Douglas fir (''Pseudotsuga menziesii'') is an evergreen conifer species in the pine family, Pinaceae. It is the tallest tree in the Pinaceae family. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Or ...

, but not as much so as

grand Grand may refer to: People with the name * Grand (surname) * Grand L. Bush (born 1955), American actor Places * Grand, Oklahoma, USA * Grand, Vosges, village and commune in France with Gallo-Roman amphitheatre * Grand County (disambiguation), ...

white fir ''Abies concolor'', the white fir, concolor fir, or Colorado fir, is a coniferous tree in the pine family Pinaceae. This tree is native to the mountains of western North America, including the Sierra Nevada and southern Rocky Mountains, and int ...

. It grows slowly when needed to outlast competition. This tree is the preferred host of a

wood wasp Sawflies are wasp-like insects that are in the suborder Symphyta within the order Hymenoptera, alongside ants, bees, and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plan ...

, '' 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 ''Phoradendron libocedri'' is a species of flowering plant in the sandalwood family known by the common name incense-cedar mistletoe. It is native to western North America from Oregon to Baja California, where it grows in forests on its host tre ...

''), a

parasitic plant A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All Parasite, parasitic plants develop a specialized organ ...

which can often be found hanging from its branches. Fire scars provide an entry point for ''Tyromyces amarus'' (pocket dry rot). ''

Gymnosporangium ''Gymnosporangium'' is a genus of heteroecious plant-pathogenic fungi which alternately infect members of the family Cupressaceae, primarily species in the genus ''Juniperus'' (junipers), and members of the family Rosaceae in the subfamily Amy ...

'' 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 Foraging is searching for wild food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce. Foraging theory is a branch of behavioral ecology that studies the foraging behavi ...

. According to the

United States Department of Agriculture The United States Department of Agriculture (USDA) is an executive department of the United States federal government that aims to meet the needs of commercial farming and livestock food production, promotes agricultural trade and producti ...

, 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 chest A hope chest, also called dowry chest, cedar chest, trousseau chest, or glory box, is a piece of furniture once commonly used by unmarried young women to collect items, such as clothing and household linen, in anticipation of married life. Th ...

s. It was once the primary material for wooden

pencil A pencil () is a writing or drawing implement with a solid pigment core in a protective casing that reduces the risk of core breakage and keeps it from marking the user's hand. Pencils create marks by physical abrasion, leaving a trail of ...

s, because it is soft and tends to sharpen easily without forming splinters.

Native Americans

Indigenous peoples of California Indigenous peoples of California, commonly known as Indigenous Californians or Native Californians, are a diverse group of nations and peoples that are indigenous to the geographic area within the current boundaries of California before and afte ...

use the plant in traditional medicine,

basket making Basket weaving (also basketry or basket making) is the process of weaving or sewing pliable materials into three-dimensional artifacts, such as baskets, mats, mesh bags or even furniture. Craftspeople and artists specialized in making baskets ...

, 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 The Maidu are a Native Americans in the United States, Native American people of northern California. They reside in the central Sierra Nevada (U.S.), Sierra Nevada, in the watershed area of the Feather River, Feather and American River, American ...

Concow tribe name for the plant is hö'-tä (

Konkow language The Konkow language, also known as Northwest Maidu (also ''Concow-Maidu'', or ' in the language itself) is a part of the Maiduan language group. It is spoken in California. It is severely endangered, with three remaining elders who learned to ...

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 th ...

, for planting in gardens and parks. It is used in traditional, xeriscapic,

native plant In biogeography, a native species is indigenous to a given region or ecosystem if its presence in that region is the result of only local natural evolution (though often popularised as "with no human intervention") during history. The term is equi ...

, and

wildlife garden A wildlife garden (or habitat garden or backyard restoration) is an Biophysical environment, environment created with the purpose to serve as a sustainable haven for surrounding wildlife. Wildlife gardens contain a variety of habitats that cater t ...

s; and also in designed

natural landscaping Natural landscaping, also called native gardening, is the use of native plants including trees, shrubs, groundcover, and grasses which are local to the geographic area of the garden. Benefits Maintenance Natural landscaping is adapted to t ...

and

habitat restoration Ecological restoration, or ecosystem restoration, is the process of assisting the recovery of an ecosystem that has been degraded, damaged, destroyed or transformed. It is distinct from conservation in that it attempts to retroactively repair ...

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 The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

in the

Northwestern United States The Northwestern United States, also known as the American Northwest or simply the Northwest, is an informal geographic region of the United States. The region consistently includes the states of Oregon, Washington, Idaho, Montana and Wyoming ...

and

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

, 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 ge ...

. 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 The California Floristic Province (CFP) is a floristic province with a Mediterranean-type climate located on the Pacific Coast of North America with a distinctive flora similar to other regions with a winter rainfall and summer drought climat ...

. Other cultivated species from the family

Cupressaceae Cupressaceae or the cypress family is a family of conifers. The family includes 27–30 genera (17 monotypic), which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdioecious or (rarely) dioecio ...

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 The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

, 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 ...

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 Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

and

virus A virus is a submicroscopic infectious agent that replicates only inside the living Cell (biology), cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are ...

es. These antimicrobial properties could potentially be used for therapies in developing countries, although more testing and

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

s should be done before such measures are implemented.

Gallery

Calocedrus decurrens copa.jpg, Adult specimen Calocedrus decurrens Incense Cedar.jpg, Tree in

McMinnville, Oregon McMinnville is the county seat of and the most populous city in Yamhill County, Oregon, Yamhill County, Oregon, United States at the base of the Oregon Coast Range. The city is named after McMinnville, Tennessee. As of the 2020 United States cens ...

Incense Cedar in Lassen VNP.jpg, Trunks in

Lassen Volcanic National Park Lassen Volcanic National Park is a List of national parks of the United States, national park of the United States in northeastern California. The dominant feature of the park is Lassen Peak, the largest lava dome, plug dome volcano in the wo ...

, 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

* * * {{Authority control decurrens Least concern plants Trees of Northern America 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