World Library  
Flag as Inappropriate
Email this Article
 

Incense-cedar

Template:PAGENAMEBASE
Calocedrus decurrens, California incense cedar.
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cupressaceae
Genus: Calocedrus
Kurz
Species
  • see text

Calocedrus (common name incense cedar) is a genus of four species of coniferous trees in the cypress family Cupressaceae. The generic name means "beautiful cedar".

Description

The genus is related to the genus Thuja, and has similar overlapping scale-leaves. Calocedrus differs from Thuja in the scale leaves being in apparent whorls of four (actually opposite decussate pairs like Thuja, but not evenly spaced apart as in Thuja, instead with the successive pairs closely then distantly spaced), and in the cones having just 2–3 pairs of moderately thin, erect scales, rather than 4–6 pairs of very thin scales in Thuja.


Species

Calocedrus decurrens

Calocedrus decurrens, California incense cedar (syn. Libocedrus decurrens), is native to western North America, with the bulk of the range in the United States, from central western Oregon through most of California and the extreme west of Nevada, and also a short distance into northwest Mexico in northern Baja California. It is a large tree, typically reaching heights of 40–60 m and a trunk diameter of up to 3 m (maxima, 69 m tall and 3.9 m diameter), and with a broad conic crown of spreading branches. The leaves are bright green on both sides of the shoots, and the cones 2–2.5 cm long. It is by far the most widely known species in the genus, and is often simply called "incense cedar" without the regional qualifier. This tree is the preferred host of a wood wasp, Syntexis libocedrii which lays its eggs in the smoldering wood immediately after a forest fire. The epithet decurrens is the present participle of dēcurrō, meaning running or flowing down.

Calocedrus formosana

Calocedrus formosana, Taiwan incense cedar, is endemic on Taiwan. It is very similar to C. macrolepis, and some botanists treat it as a variety of that, C. macrolepis var. formosana. It is a medium-sized tree, growing to 25–30 m tall, and is rare in the wild, occurring only as scattered trees in mixed forests. The leaves are glaucous green on the upper side of the shoots, and conspicuously marked with bright white stomatal patches on the underside. The cones are 1.5–2 cm long, carried on a 1–1.5 cm stem.

Calocedrus huashanensis

Calocedrus huashanensis is an extinct species which was described in 2012. It is known from compression fossils found in the Oligocene age Ningming Formation of southern China. C. huashanensis is known from branches and leaves.

Calocedrus macrolepis

Calocedrus macrolepis, Chinese incense cedar, is native to southwest China from Guangdong west to Yunnan, and also in northern Vietnam, northern Laos, extreme northern Thailand and northeastern Myanmar (Burma). It is also a medium-size tree to 25–30 m tall, and like C. formosana, is rare in the wild. The leaves and cones are similar to C. formosana, differing most obviously in the shorter cone stem, only 0.5 cm long.

Calocedrus rupestris

Calocedrus rupestris, the most recently discovered living species of Calocedrus, was identified in Vietnam and first described in 2004. It occurs exclusively on rocky limestone (karst) terrain, a habitat that has a very high level of endemism. The close proximity of these populations to the Chinese and Laotian borders indicates that the species may occur in those countries as well. It is an evergreen, monoecious tree up to 25 m tall with a broadly rounded crown. The epithet "rupestris" means "rock-dwelling".[1]

Uses


Lumber

The wood of Calocedrus is soft, moderately decay-resistant, and with a strong spicy-resinous fragrance. That of C. decurrens is the primary material for wooden pencils, because it is soft and tends to sharpen easily without forming splinters. The two Asian species were (at least in the past) in very high demand for coffin manufacture in China, due to the scent of the wood and its decay resistance. It is likely that past over-exploitation is responsible for their current rarity.

Incense cedar was the preferred hearth board of the Native Peoples of Northern California for lighting fires by friction .

Cultivation

Calocedrus decurrens, the California incense cedar, is a popular ornamental tree, grown particularly in locations with cool summer climates like Britain, Washington and British Columbia. Its very narrow columnar crown in landscape settings, an unexplained consequence of the climatic conditions in these areas, is not shown by trees in their native 'wild' habitat. The California incense cedar is also valued for its drought tolerance. The Asian species are rarely cultivated.

References

Further reading

  • , Bulletin No. 95, pp. 17-20 retrieved Nov. 13, 2011

External links

  • Arboretum de Villardebelle - cone photos
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.