Agathis

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Agathis
Agathis australis (New Zealand kauri)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Gymnospermae
Division: Pinophyta
Class: Pinopsida
Order: Araucariales
Family: Araucariaceae
Genus: Agathis
Salisb., 1807
Distribution of Agathis species
Synonyms[1]
  • Dammara (Rumph., 1741) Lam., 1786 ex Link, 1822
  • Salisburyodendron A.V.Bobrov & Melikyan

Agathis, commonly known as kauri or dammara, is a genus of 22 species of evergreen tree. The genus is part of the ancient conifer family Araucariaceae, a group once widespread during the Jurassic and Cretaceous periods, but now largely restricted to the Southern Hemisphere except for a number of extant Malesian Agathis.[1][2]

Description

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

Mature kauri trees have characteristically large trunks, forming a trunk 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.[3]

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, asending. 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

Kauri logs and loggers near Piha

Various species of kauri give diverse resins such as kauri gum, Manila 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 guitars and ukuleles due to its low density and 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

Accepted species[1]
Image Scientific name Common Name Distribution
Agathis atropurpurea black kauri, blue kauri Queensland, Australia
Agathis australis kauri, New Zealand kauri North Island, New Zealand
Agathis borneensis western Malesia, Borneo
Agathis corbassonii red kauri New Caledonia
Agathis dammara (syn. A. alba, A. celebica, A. loranthifolia) Bindang eastern Malesia
Agathis flavescens Peninsular Malaysia
Agathis jurassica
Agathis kinabaluensis Borneo
Agathis labillardieri New Guinea
Agathis lanceolata New Caledonia
Agathis lenticula Borneo
Agathis macrophylla (syn. A. vitiensis) Pacific kauri, dakua Fiji, Vanuatu, Solomon Islands
Agathis microstachya bull kauri Queensland, Australia
Agathis montana New Caledonia
Agathis moorei white kauri New Caledonia
Agathis orbicula Borneo
Agathis ovata New Caledonia
Agathis philippinensis Philippines, Sulawesi
Agathis robusta Queensland kauri Queensland, Australia; New Guinea
Agathis silbae Vanuatu
Agathis spathulata New Guinea kauri Papua New Guinea
Agathis zamunerae Patagonia, South America Argentina
Formerly included[1]

Moved to Nageia

  1. Agathis motleyi - Nageia motleyi
  2. Agathis veitchii - Nageia nagi

Gallery

References

  1. ^ a b c d Kew World Checklist of Selected Plant Families
  2. ^ de Laubenfels, David J. 1988. Coniferales. P. 337–453 in Flora Malesiana, Series I, Vol. 10. Dordrecht: Kluwer Academic.
  3. ^ Whitmore, T.C. 1977. A first look at Agathis. Tropical Forestry Papers No. 11. University of Oxford Commonwealth Forestry Institute.

External links