Agathis

Location & distribution maps

Species on website:   A atropurpurea,     A microstachya,      A robusta     

Plant description

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:

• https://en.wikipedia.org/wiki/Agathis (2023)