The Gymnosperm Database

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Photo of a cultivated specimen [Chad Husby] (new window opens at the Flickr website).

 

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Agathis macrophylla

(Lindl.) Mast. 1892

Conservation status 2013

Common names

Fijian kauri, dakua, ndakua (Fiji), nendö, notopiti (Santa Cruz Group), kauri (Vanuatu) (Farjon 2010).

Taxonomic notes

Syn: Dammara macrophylla Lindl. 1851, Agathis obtusa (Lindl.) Mast. 1892, D. brownii hort. ex Lem. 1855, A. brownii (Lem.) L.H. Bailey 1933, D. vitiensis Seem. 1868, A. vitiensis (Seem.) Benth. & Hook. f. 1880 (Farjon 2010).

It were better named Agathis heterophylla, because no other kauri has such variable leaves; continuous variation is shown in herbarium specimens from throughout the range of the species. Pollen cone characters, which have been found to provide a sound basis for species differentiation in Agathis, are quite consistent through its range, and in this area the only other species is A. silbae, which is clearly distinct (Farjon 2010).

Description

Trees to 40 m tall and 100 cm dbh with a clear bole below a broad crown of spreading and ascending branches. Bark gray, scaly, exfoliating in irregular patches; inner bark reddish. Twigs nearly quadrangular, smooth, olive-brown. Leaves subopposite on short, flattened petioles, coriaceous, with several subparallel nerves, light green to glaucous. Leaves on young understory trees are broad-lanceolate, 8-17 × 3-6 cm, apex acute to obtuse; leaves in mature tree crowns are oval to ovate-lanceolate, 4-8 × 1.5-3 cm, apex obtuse to round. Pollen cones axillary, solitary, 25-45 × 8-15 mm on a 3-7 mm stout peduncle; microsporophylls imbricate with a 1.4-2.2 mm wide head, 1.8-2.2 mm high, margin minutely erose-denticulate. Seed cones solitary on thick peduncles, 10-13 cm diameter, globose, smooth, green, sometimes glaucous, resinous, brown when ripe. Cone scales 3.5 cm long, 3.5-4.5 cm wide; seeds 12-15 × 7-8 mm, ovoid-oblong, with a large wing 20-25 x 10-15 mm and a small wing just 3-6 mm wide (Farjon 2010, Silba 1986).

Distribution and Ecology

Fiji: Kadavu Is., Viti Levu, Vanua Levu; Solomon Is.: Santa Cruz Group (Utupua and Vanikoro Is.); Vanuatu: Aneityum, Erromango, and Tana Is.; at 75-900 m elev. Typically appears as an emergent tree in lowland to low montane tropical rainforests, usually on soils derived from volcanic rocks (Farjon 2010). It employs a gap-phase regeneration strategy and thus is able to perpetuate itself within the forests in the absence of major disturbance (Enright and Hill 1995, cited by Farjon 2010).

Islands where Agathis macrophylla grows in habitat.

Although the species has an overall redlist status of Near Threatened, some individual island populations are severely threatened, e.g. on Utupua Is. An unlogged population apparently survives on the upper Lawrence River on Vanikoro, but otherwise, the species is now largely restricted to plantations, and reassessment is likely to find that it has declined to a Vulnerable status (Farjon 2010).

Remarkable Specimens

The Big Dakua in Colo-I-Suva Forest Park on Viti Levu is the only really large extant tree that I have seen mentioned anywhere. See Tasmanian Geographic (2014) for a description of how to find the tree (it is featured prominently at the park). No photos or measurements are given, though.

Ethnobotany

The wood is white or pale reddish and in commerce is known as dakua or as Vanikoro kauri. It is valuable for construction, boatbuilding and furniture. As with most species of Agathis it produces quantities of an aromatic resin that has been burned in lamps and used as varnish, though these uses are now archaic. The soot of burnt resin is used to dye cloth black. The species is planted commercially in the Santa Cruz Group and elsewhere as a renewable source of a highly valued wood (Farjon 2010).

One exploratory collection to evaluate dendrochronological potential found that "The nature of the wood formation in this species led to problems in the analysis of the cores and poor statistical confidence in the results", although the species is usable for tree age determinations if stem sections can be taken (Weaver 1988). A second study (Ash 1985) found that number of rings was only an approximate indicator of age.

Observations

They are readily seen at Colo-I-Suva Forest Park in Suva on Viti Levu (Tasmanian Geographic 2014).

Remarks

The epithet refers to this species' relatively large leaves (compared to other Agathis).

Citations

Ash, J. 1985. Growth rings and longevity of Agathis vitiensis (Seemann) Benth. & Hook. f. ex Drake in Fiji. Australian Journal of Botany 33(1):81-88.

Lindley. 1851. Journal of the Horticultural Society 6:271. Available at the Biodiversity Heritage Library, accessed 2015.01.16. The description is based solely upon a letter to Lindley from Charles Moore (commemorated in Agathis moorei, also described by Lindley in this publication). For convenience, the full text is reproduced here:
"The other has very large ovate-lanceolate leaves, 7 inches long by 2 broad, and cones much like those of a Cedar of Lebanon in size and form. Of this Mr. Moore says: 'A native of the island of Vanicolla, one of Queen Charlotte's group, allied to the Kauri of Amboyna (Dammara alba), but with larger cones and leaves. It is a noble-looking tree, somewhat stiff in habit, yet with wide-spreading branches. Some of the stems are at least 100 feet high.' Its large leaves suggest the following name and specific character:
"D. macrophylla: foliis magnis ovato-lanceolatis acutis, strobilis spheroideis (4-uncialibus), squamarum apicibus planis arete adpressis quintuple latoribus quam longis."

Masters, Maxwell T. 1892. List of conifers and taxads in cultivation in the open air in Great Britain and England. Journal of the Royal Horticultural Society 16:179-256 (see p. 197). For convenience, the full text is reproduced here:
2. A. macrophylla.
Synonym: Dammara macrophylla, Lindley in Journ. Hort. Soc. vi. p. 271; Parlatore, 376.
South Sea Islands. Conservatories.

Tasmanian Geographic. 2014.06.22. On the Trail of the Fijian Kauri, Tasmanian Geographic 20, accessed 2015.01.16.

Weaver, S.A. 1988. The use of increment cores for the analysis of tree ring chronologies for Fijian kauri (Agathis macrophylla). Tuatara (Wellington) 30:51-54.

See also

The species account at Threatened Conifers of the World.

Last Modified 2023-11-01