Agathis
Kauri
Kauri
Wikipedia links: Gymnosperms > Cupressales > Araucariaceae > Agathis
Other links:
Species on website: A atropurpurea, A microstachya, A robusta
Common name: Kauri
Also, Dammara
Conservation status: . . .
Etymology:
Cones and seed:
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
Leaves:
Its leaves are much broader than most conifers
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
Stem & branches:
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
Roots:
Habit:
Evergreen coniferous tree
Mature kauri trees have characteristically large trunks, 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
Habitat:
Distribution:
Native to Australasia and Southeast Asia
Species:
World: 22 species
Australia: ?
Additional notes:
It is one of three extant genera in the family Araucariaceae, alongside Wollemia and Araucaria
Uses
Various species of kauri give diverse resins such as kauri 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
Due to the hard resin of the wood, it was the traditionally preferred material used by Māori for wooden weapons, patu aruhe (fernroot beaters) and barkcloth beaters
Evolutionary history
Within Araucariaceae, Agathis is more closely related to Wollemia than to Araucaria
The oldest fossils currently confidently assignable to Agathis are those of Agathis immortalis from the Salamanca Formation of Patagonia, which dates to the Paleocene, approximately 64.67–63.49 million years ago
Agathis-like leaves are also known from the slightly older Lefipán Formation of the same region, which date to the very end of the Cretaceous
Other fossils of the genus are known from the Eocene of Patagonia, the Late Paleocene-Miocene of southern Australia, and the Oligocene-Miocene of New Zealand
Agathis-like remains are also found in the older Bahariya Formation of Egypt
Sources of information: