Widdringtonia

From Wikipedia, the free encyclopedia

Widdringtonia
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cupressaceae
Subfamily: Callitroideae
Genus: Widdringtonia
Endl.
Species

Widdringtonia cedarbergensis
Widdringtonia nodiflora
Widdringtonia schwarzii
Widdringtonia whytei

Widdringtonia is a genus of coniferous trees in the Cupressaceae (cypress family). There are four species, all native to southern Africa, where they are known in the past as "cedars" (to which they are not related) but are now known as African cypresses.

They are large shrubs or trees, reaching 5-20 m tall (to 40 m in W. whytei). The leaves are evergreen and scale-like, except on seedlings, which have needle-like leaves 1-1.5 cm long. The adult scale leaves are arranged in decussate opposite pairs in four rows along the twigs, while the juvenile needle leaves are arranged spirally.

The male cones are small, 3-6 mm long, and are located at the tips of the twigs. The female cones start out similarly inconspicuous, maturing in 18-20 months to 2-3 cm long and wide, globular to ovoid, with four, thick, woody scales, arranged in two opposite pairs. The cones mostly remain closed on the trees for many years, opening only after being scorched by a wildfire; this then releases the seeds to grow on the newly cleared burnt ground. 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 and Actinostrobus from Australia, which differ in their cones and leaves being in whorls of three, not opposite pairs.

[edit] 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.

[edit] References and external links

Languages