Hardwood

Hardwood

__NOTOC__The term hardwood is used to describe wood from broad-leaved angiosperm trees, mostly deciduous, but not necessarily, in the case of tropical trees. Hardwood contrasts with softwood, which comes from conifer trees. On average, hardwood is of higher density and hardness than softwood, but there is considerable variation in actual wood hardness in both groups, with a large amount of overlap; some hardwoods (e.g. balsa) are softer than most softwoods, while yew is an example of a hard softwood. Hardwoods have broad leaves and enclosed nuts or seeds such as acorns. They often grow in subtropical regions like Africa and south-east Asia, but also in temperate regions such as Europe and North America. The dominant feature separating hardwoods from softwoods is the presence of pores, or vessels. [CRC Handbook of Materials Science, Vol IV, pg 15] Examples of European hardwoods from evergreen trees include holly ("Ilex aquifolium"), boxwood from "Buxus sempervirens" and oak from the holm oak "Quercus ilex". Common deciduous European and North American hardwood species include the oaks ("Quercus" species), beech ("Fagus" species), ash ("Fraxinus" species), maple ("Acer" species) and cherry ("Prunus" species). Important tropical hardwoods include teak ("Tectona"), mahogany ("Swietenia"), iroko ("Chlorophora excelsa"), ebony ("Diospyros ebenum") and rubberwood ("Hevea brasiliensis").

Hardwood species are more varied than softwood. There are about a hundred times as many hardwood species as softwoods. The vessels may show considerable variation in size, shape of perforation plates (simple, scalariform, reticulate, foraminate), and structure of cell wall (e.g. spiral thickenings).

Hardwoods are employed in a large range of applications including: construction, furniture, flooring, utensils, etc.

Solid hardwood joinery is expensive compared to softwood. In the past, tropical hardwoods were easily available but the supply of some species such as Burma teak and mahogany is now becoming restricted due to sustainability issuesFact|article|date=December 2007). Cheaper "hardwood" doors, for instance, now consist of a thin veneer bonded to a core of softwood, plywood or medium-density fibreboard (MDF).

See also

*List of woods
*Softwood
*Wood flooring
*Janka Wood hardness rating

References

Further reading

*Schweingruber, F.H. (1990) "Anatomie europäischer Hölzer—Anatomy of European woods." Eidgenössische Forschungsanstalt für Wald, Schnee und Landscaft, Birmensdorf (Hrsg,). Haupt, Bern und Stuttgart.
*Timonen, Tuuli (2002). "Introduction to Microscopic Wood Identification". Finnish Museum of Natural History, University of Helsinki.
*Wilson, K., and D.J.B. White (1986). "The Anatomy of Wood: Its Diversity and variability." Stobart & Son Ltd, London.

External links

* [http://www2.fpl.fs.fed.us/TechSheets/techmenu.html Center for Wood Anatomy Research]
* [http://www.sawdustandshavings.com/wood_information/ Hardwood Information Chart]


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Look at other dictionaries:

  • hardwood — hard wood adj. Made of the hard to cut wood of a broad leaved tree, as e.g. oak; consisting of a hardwood; as, hardwood floors; of wood and wooden objects. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • hardwood — hard wood n. The wood of broad leaved dicotyledonous trees (as distinguished from the wood of conifers); also items made from such wood; as, decorative hardwood. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • hardwood — [härd′wood΄] n. 1. any tough, heavy timber with a compact texture 2. Forestry the wood of an angiosperm possessing true vessels, in contrast to the softwood of a gymnosperm, which lacks vessels 3. a tree yielding hardwood …   English World dictionary

  • hardwood — 1560s, from HARD (Cf. hard) + WOOD (Cf. wood). From deciduous trees, distinguished from that of pines and firs …   Etymology dictionary

  • hardwood — ► NOUN ▪ the wood from a broadleaved tree as distinguished from that of conifers …   English terms dictionary

  • hardwood — I. noun Date: 1568 1. the wood of an angiospermous tree as distinguished from that of a coniferous tree 2. a tree that yields hardwood 3. a basketball court II. adjective Date: circa 1817 1. having or made of hardwood < hardwood floors > …   New Collegiate Dictionary

  • hardwood — /hahrd wood /, n. 1. the hard, compact wood or timber of various trees, as the oak, cherry, maple, or mahogany. 2. a tree yielding such wood. adj. 3. made or constructed of hardwood: a hardwood floor. [1560 70; HARD + WOOD1] * * * Timber obtained …   Universalium

  • hardwood — [[t]hɑ͟ː(r)dwʊd[/t]] hardwoods N MASS: oft N n Hardwood is wood such as oak, teak, and mahogany, which is very strong and hard. ...imports of tropical hardwood. ...hardwood floors. Ant: softwood …   English dictionary

  • hardwood — UK [ˈhɑː(r)dˌwʊd] / US [ˈhɑrdˌwʊd] noun [countable/uncountable] Word forms hardwood : singular hardwood plural hardwoods hard strong wood from trees such as oak or mahogany • See: softwood …   English dictionary

  • hardwood — noun Hardwood is used before these nouns: ↑floor, ↑forest …   Collocations dictionary

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