Agathis

Agathis
For the braconid wasp genus, see Agathis (wasp).
For details on New Zealand Kauri, see Agathis australis
The type of gastropod marine mollusc is spelled cowrie, while the New Zealand land mollusc is spelled Kauri .
Agathis
Agathis australis (New Zealand Kauri)
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Araucariaceae
Genus: Agathis
Salisb.
Species

See text

The genus Agathis, commonly known as kauri or dammar, is a relatively small genus of 21 species of evergreen tree. The genus is part of the ancient Araucariaceae family of conifers, a group once widespread during the Jurassic period, but now largely restricted to the Southern Hemisphere except for a number of extant Malesian Agathis.[1]

Contents

Description

Mature kauri trees have characteristically large trunks, forming a bole with little or no branching below the crown. In contrast, young trees are normally conical in shape, forming a more rounded or irregularly shaped crown as they achieve maturity.[2]

Bark of Agathis robusta at Melbourne Royal Botanic Gardens (leaves belong to another plant)

The bark is smooth and light grey to grey-brown, usually peeling into irregular flakes that become thicker on more mature trees. The branch structure is often horizontal or, when larger, ascending. The lowest branches often leave circular branch scars when they detach from the lower trunk.

The juvenile leaves in all species are larger than the adult, more or less acute, varying among the species from ovate to lanceolate. Adult leaves are opposite, elliptical to linear, very leathery and quite thick. Young leaves are often a coppery-red, contrasting markedly with the usually green or glaucous-green foliage of the previous season.

The male pollen cones appear usually only on larger trees after seed cones have appeared. The female seed cones usually develop on short lateral branchlets, maturing after two years. They are normally oval or globe shaped.

Seeds of some species are attacked by the caterpillars of Agathiphaga, some of the most primitive of all living moths.

Uses

Various species of kauri give diverse resins such as kauri copal, Manilla copal and Dammar gum. The timber is generally straight-grained and of fine quality with an exceptional strength-to-weight ratio and rot resistance, making it ideal for yacht hull construction. The wood is commonly used in the manufacture of low priced guitars due to its good resonating properties, yet relatively low price of production. It is also used for some Go boards (goban). The uses of the New Zealand species (A. australis) included shipbuilding, house construction, wood panelling, furniture making, mine braces, and railway sleepers.

Species list

Te Matua Ngahere, an A. australis in Waipoua Forest, is the second largest tree in New Zealand. The largest tree, Tāne Mahuta, is nearby.

References

  1. ^ de Laubenfels, David J. 1988. Coniferales. P. 337-453 in Flora Malesiana, Series I, Vol. 10. Dordrecht: Kluwer Academic.
  2. ^ Whitmore, T.C. 1977. A first look at Agathis. Tropical Forestry Papers No. 11. University of Oxford Commonwealth Forestry Institute.

External links


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Look at other dictionaries:

  • Agathis — Agathis …   Wikipédia en Français

  • agathis — ● agathis nom masculin (grec agathis, faisceau) Grand arbre résineux (araucarioïdée) d Australie et des îles voisines, à feuilles coriaces et persistantes, au bois utilisé en ébénisterie et dont la résine transparente est le dammar. ● agathis… …   Encyclopédie Universelle

  • Agathis —   [griechisch agathís »Knäuel« (nach dem dichten Stand der Blüten)], Gattung der Araukariengewächse mit etwa 15 Arten, die von Südostasien bis Neuseeland vorkommen. Einige Agathisarten liefern wertvolles Bau und Möbelholz. Aus dem Harz ihrer… …   Universal-Lexikon

  • Agăthis — Agăthis, 1) Untergattung der Brakwe spen, s.d.; 2) (A. Salisb.), Pflanzengattung aus der Familie der Zapfenbäume (Abietineae) zu Dammara Rumph., Monoecia L. gehörig; A. lorantifolia, Baum auf Amboina …   Pierer's Universal-Lexikon

  • Agathis — Salisb. (Dammarfichte), Gattung der Koniferen, immergrüne, hohe, harzreiche Bäume mit an den fast wirteligen Ästen meist zweizeiligen und oft paarweise zusammengerückten, breiten, flachen, am Grunde stielartig zusammengezogenen, lederartigen… …   Meyers Großes Konversations-Lexikon

  • Agathis — Agāthis Salisb., Pflanzengattg., s. Dammara …   Kleines Konversations-Lexikon

  • Agathis — Kauri Bäume Agathis dammara, Illustration Systematik Abteilung: Pinophyta Klasse: Pinopsida …   Deutsch Wikipedia

  • Agathis — Agathis …   Wikipédia en Français

  • Agathis —   Agathis Ilustración de …   Wikipedia Español

  • Agathis — noun kauri pine • Syn: ↑genus Agathis • Hypernyms: ↑gymnosperm genus • Member Holonyms: ↑Araucariaceae, ↑family Araucariaceae, ↑araucaria family …   Useful english dictionary

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