Widdringtonia
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''Widdringtonia'' is a genus 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 In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s in the
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 ...
(
cypress Cypress is a common name for various coniferous trees or shrubs of northern temperate regions that belong to the family Cupressaceae. The word ''cypress'' is derived from Old French ''cipres'', which was imported from Latin ''cypressus'', the ...
family). The name was Austrian botanist Stephan Endlicher's way of honouring an early expert on the coniferous forests of Spain, Capt. Samuel Edward Widdrington (1787–1856). There are four species, all native to southern
Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
, where they are known as cedars or African cypresses.


Description

This genus contains large evergreen
shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...
s and
tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s, reaching 5–20 m tall (to 40 m in ''W. whytei''). Juveniles have needle-like leaves that are arranged in spirals. The scale-like leaves in adults are arranged in decussate opposite pairs in four rows along the twigs. The plants are dioecious. The small male cones grow at the ends of twigs. The scales have no stalks. They grow into an upward, decreasing beak with two to six pollen sacs at the base of the cone. The female cones are small and stalkless and grow in short spikes on the branches. The scales grow in two opposite rows that spread at the base during pollination. They then close into a corky, leathery cone with five or more ovules at the base of each scale. The cones become woody as they mature. The cones mostly remain closed on the trees for many years, opening only after being scorched by a
wildfire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...
; this then releases the
seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s to grow on the newly cleared burnt ground. They open at four very thick valves that correspond to the four scales. Each cone produces few seeds. They are wing with hard test and two cotyledons. In ''W. whytei'' the cones open soon after maturity to shed the seed without fire; this species is more sensitive to fire and only grows in moister situations where it is protected from fire. The best adapted to fire is ''W. nodiflora'', which has the ability to re-grow from the roots, as well as by seed.


Species

One species is widespread in southern Africa, while the other three have restricted ranges, often occurring with or near to the widespread species. The closest relatives of ''Widdringtonia'' are ''
Callitris ''Callitris'' is a genus of coniferous trees in the Cupressaceae (cypress family). There are 16 recognized species in the genus, of which 13 are native to Australia and the other three (''C. neocaledonica, C. sulcata'' and ''C. p ...
'' and ''
Actinostrobus ''Actinostrobus'' is a genus of coniferous trees in the Cupressaceae (cypress family). Common names include cypress, sandplain-cypress and cypress-pine, the last of these shared by the closely related genus '' Callitris''. Species There are th ...
'' from
Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
, which differ in their cones and leaves being in whorls of three, not opposite pairs.


Uses

The wood is light, soft and aromatic. It can be easily split and resists decay. It is used to make furniture, indoor and outdoor panelling, and fence posts. That of ''W. whytei'' was particularly valuable as it was available in large sizes, but this species is now endangered and no longer cut to any extent.


References and external links

* Pauw, C. A. & Linder, H. P. 1997. ''Widdringtonia'' systematics, ecology and conservation status. ''Bot. J. Linn. Soc.'' 123: 297–319.
Recommended English names for trees of Southern Africa
(archive)

{{Taxonbar, from=Q117681 Afromontane flora Conifer genera Trees of South Africa Taxa named by Stephan Endlicher