''Agathis macrophylla'' (also ''
Agathis silbae'') known as Pacific kauri, is a
coniferous
Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extant ...
tree native to the islands of the southwestern
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
in tropical humid lowlands and lower montane regions, notably in
Fiji
Fiji ( , ,; fj, Viti, ; Fiji Hindi: फ़िजी, ''Fijī''), officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists ...
,
Vanuatu
Vanuatu ( or ; ), officially the Republic of Vanuatu (french: link=no, République de Vanuatu; bi, Ripablik blong Vanuatu), is an island country located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of no ...
, the
Santa Cruz Islands, and the
Solomon Islands
Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...
. The Pacific kauri is one of the largest and fastest growing species in its genus, and is important in
forestry
Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests, woodlands, and associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. Th ...
.
Description
It is a large
evergreen
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...
tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
, reaching 40 m in height and 3 m in diameter. It possesses the mottled, shedding
bark
Bark may refer to:
* Bark (botany), an outer layer of a woody plant such as a tree or stick
* Bark (sound), a vocalization of some animals (which is commonly the dog)
Places
* Bark, Germany
* Bark, Warmian-Masurian Voivodeship, Poland
Arts, ...
that is characteristic of other
kauri species. Young trees are narrow and conic in shape, but begin to grow a wider, deeper
canopy after attaining a trunk diameter of 30–50 cm. In mature specimens, the
trunk
Trunk may refer to:
Biology
* Trunk (anatomy), synonym for torso
* Trunk (botany), a tree's central superstructure
* Trunk of corpus callosum, in neuroanatomy
* Elephant trunk, the proboscis of an elephant
Computing
* Trunk (software), in rev ...
is generally straight or slightly tapered and clear for 15–20 m before branching into a spreading canopy up to 35 m in diameter. The
root
In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the sur ...
system is deep and strong, and the trees are highly wind resistant.
The
leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
are green and glossy, elliptical to
lanceolate
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...
, 7–15 cm long and 2–4 cm wide. They are borne on short
petioles and held in a decussate pairs, but twisted so they lie in one plane. Leaves in the shade, of juvenile trees, and of individuals growing in wetter regions, tend to be larger.
Male
cones of ''A. macrophylla'' are elliptical and measure roughly 2–5 cm long at
pollen shed. The short pollen cones help distinguish this species from related ''Agathis'' species. Female (seed) cones are globular, 8–13 cm across, and are borne on short
wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...
y stalks. The majority of the cone crop matures early to mid February, as the cones turn brown and release the winged
seeds
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm pl ...
, which are small, flattened, and attached to a wing about 3.5 cm in length. Wind dispersal is very efficient; seeds have been known to travel tens of kilometres in the wind, and may even travel hundreds of kilometres during the
tropical cyclone
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...
s that occur frequently in the species' range.
Ecology
''A. macrophylla'' is one of the largest trees in its range, and occurs as a dominant
emergent tree in closed, humid, lowland-montane tropical forests. Associated plant species vary from location to location, but include ''
Cryptocarya turbinata
''Cryptocarya turbinata'' is a species of flowering plant in the laurel family, Lauraceae. It is a tree native to Fiji, Niue, the Samoan Islands, Tonga, and Vanuatu
Vanuatu ( or ; ), officially the Republic of Vanuatu (french: link=no, Ré ...
'', ''
Ilex vitiensis
''Ilex'' (), or holly, is a genus of over 570 species of flowering plants in the family Aquifoliaceae, and the only living genus in that family. ''Ilex'' has the most species of any woody dioecious angiosperm genus. The species are evergreen o ...
'', ''
Garcinia vitiensis
''Garcinia'' is a genus of flowering plants in the family Clusiaceae native to Asia, America, Australia, tropical and southern Africa, and Polynesia. The number of species is disputed; Plants of the World Online (POWO) recognise up to 400. Common ...
'', ''Palaquium'' spp., and ''
Podocarpus'' spp. in Vanuatu, ''
Calophyllum vitiense
''Calophyllum'' is a genus of tropical flowering plants in the family Calophyllaceae. They are mainly distributed in Asia, with some species in Africa, the Americas, Australasia, and the Pacific Islands.
History
Members of the genus ''Calophyllu ...
'', ''
Dacrydium nidulum'', ''
Retrophyllum vitiense
''Retrophyllum vitiense'' is a species of conifer in the family Podocarpaceae. It is a large evergreen rainforest emergent tree native to Fiji, Indonesia, Papua New Guinea, and Solomon Islands.
Description
''Retrophyllum vitiense'' is a large ...
'', ''
Fagraea berteroana'', and ''
Podocarpus'' spp. in Fiji.
It is one of the fastest growing species in its genus, capable of growing 1-1.5 metres in height annually in lightly shaded to open areas, where growth is fastest. The species is fairly shade tolerant, especially in the seedling stage, though growth is slow under suppression. Strong root systems enable mature trees to withstand cyclones and seed rapidly into gaps. The species on the whole is long lived, capable of reaching ages of 300–1000 years.
Uses
''A. macrophylla'' is a valued commercial timber species, and its wood is much sought after for many uses. The wood is a cream to gold colour (mature
heartwood is a lustrous brown) and much appreciated in the timber industry, particularly as a surface
veneer
Veneer may refer to:
Materials
* Veneer (dentistry), a cosmetic treatment for teeth
* Masonry veneer, a thin facing layer of brick
* Stone veneer, a thin facing layer of stone
* Wood veneer, a thin facing layer of wood
Arts and entertainment
* ' ...
. The dry wood has a density of approximately 540 kg/m
3.
Pacific kauri is a valuable tree throughout the southeastern Pacific (Melanesia). The timber is frequently used for house construction,
canoe
A canoe is a lightweight narrow water vessel, typically pointed at both ends and open on top, propelled by one or more seated or kneeling paddlers facing the direction of travel and using a single-bladed paddle.
In British English, the term ...
carving, and
totem pole construction. Smoke from the resin is used as a black dye for hair, clothes and tattoos, and the leaves are used in traditional medicine. Fijians value the resin itself (known as ''makadre'') to be used as pottery glaze and torch fuel.
See also
*
Agathis australis, New Zealand kauri
References
Notes
*
*
External links
''Agathis macrophylla''at the Gymnosperm Database.
{{Taxonbar, from=Q2732370
macrophylla
Near threatened plants