DATA SHEETS ON SPECIES UNDERGOING GENETIC IMPOVERISHMENT

DATA SHEET ON ARAUCARIA CUNNINGHAMII Aiton ex Lambert

Compiled by N.H.S. Howcroft
Forest Research Station
Office of Forests
P.O. Box 134
Bulolo
Papua New Guinea

Araucaria cunninghamii Aiton ex Lambert, in Australia, Papua New Guinea and West Irian.

Synonymy: Araucaria cunninghamii Aiton ex Lambert (1837) in Gen. Pin. III
Altingia cunninghamii D. Don t79 (1830) in Hort. Brit. p.403 (nomen nudum)
Araucaria cunninghamii Sweet (1830) Hort. Brit. ed. 11, p.475 (nomen nudum)
Araucaria cunninghamii D. Don (1839) Hort. Brit. ed. 111, p.623 (nomen nudum)
Araucaria cunninghamii Ait. var. papuana Laut. (1913) in Engl. Bot. Jahrb. p.51
Araucaria beccari Warb. (1900) in Monsunia 1:187

Botanical Description:

A large symmetrical tree, unbuttressed, 50 – 70 m high. Bole straight, cylindrical, self-pruning, clear to 30 metres or more on mature trees, 1.2 – 1.7 m diameter. Crown pyramidal to flat. Outer bark coloured dark plum, red brown or grey, rough, peeling off around circumference in stringy papery layers; middle bark reddish brown; inner bark mottled white. Wood cream to almost white in colour. Exudate thick, viscous, white and resinous.

Seedling:

Cotyledons four, small, narrow linear, 10 – 30 × 1 – 4 mm, glabrous, flat.

Ramification:

Branches in whorls of up to six, more or less horizontal with second to fifth order branchlets. Trunk internodes variable, 1 – 4 m.

Juvenile Foliage:

Leaves longer and flatter than adult, 23 – 27 × 20 – 25mm. Persists until trees are about 10 years old.

Adult Foliage:

Leaves crowded in overlapping whorls on ends of branches, persistent, without petioles, narrow to broadly triangular, slightly curved, 8 – 10 mm long, glabrous, dull green colour.

Inflorescence:

Monoecious. Male strobili usually borne on lower and mid-crown branches, terminal, green, yellow at anthesis, red brown when spent, elongated, about 90 × 10 mm. Pollen spheroidal and without air sacs, wind dispersed.

Female strobili borne mostly in upper crown, terminal, green in colour, consisting of clustered, spirally arranged carpels fused with ligulate scales, developing into a green ovoid cone, 70 – 100 × 60 – 80 mm; the cone is covered with short spines, 9 – 10 mm long, porrect or deflexed.

Seed:

In the form of ovulate cone scales, more or less flat, woody, triangular with two thin wings, indehiscent. Scale terminating in a sharp spine; reddish brown in colour; seed (excluding wings), 20 – 30 × 9 – 10 mm. There are approximately 4 000 dry seeds per kilogram.

Habitat and Ecology:

In the island of New Guinea, this conifer has a discontinuous distribution ranging from the headwaters of the Saga Aho River in the Milne Bay area of Papua at latitude 10°04'S, longitude 150°15'E, altitude 550 – 900 m a.s.l., up to the north-western end of the Vogelkop of West Irian near Sausapor at latitude 0°03'S, longitude 132°05'E, altitude approximately 800 m a.s.l. (Aubreville, 1965; Gray 1971; Havel, 1971; Zieck, 1975 pers. comm.). This species is also indigenous to Australia. It has a discontinuous and narrow distribution along the east coast there, ranging from Kempsey in New South Wales at latitude 31°S to Cape Grenville on Cape York Peninsula in North Queensland at latitude 12°S. It occurs naturally from sea level to over 1 000 m a.s.l., throughout its range in Australia (Reilly, 1974).

The altitudinal range of the species in New Guinea is from 60 to 2 745 m a.s.l. Due to the remoteness of many of the known stands there are no accurate meteorological data from them. Mean monthly maximum temperatures range from 25°C on the coast to less than 15°C in the highlands. The mean monthly minimum temperature for stands at extreme elevations (e.g. Mt. Suckling, altitude 2 745 m a.s.l.) is not known but it is probably quite low. The species is likely to be sensitive to frost. Mean monthly relative humidity ranges between 78 and 90 per cent on the coast, 60 and 80 per cent in the highlands. Mean annual rainfall at localities near natural stands in Papua New Guinea ranges from 1.929 to 4 787 mm (McAlpine et al 1975). A. cunninghamii occurs in isolated remnant pockets, or in fairly dense stands on ridges. In some instances it is found on swampy terrain. It is often associated with Araucaria hunsteinii, Castanopsis, Lithocarpus, Flindersia, Elaeocarpus, Podocarpus and Toona (Havel, 1971; Gray, 1975) and less frequently may be found associated with Nothofagus.

Stands of A. cunninghamii occur on loam, clay, sand or peat soils derived from breccias, agglomerates, coralline or limestone formations, lacustrine deposits or old volcanic deposits.

Status: Not endangered as a species but endangered in parts of its geographic range.

Reasons for Decline in Areas:

There appear to be five main reasons for the decline of the species in some areas of New Guinea. Several of these are related.

1. Demand for arable land.

2. A number of stands are known to have been seriously reduced by fires started by natural causes or by man for agricultural or hunting purposes, or through indiscriminate burning of adjacent grasslands or old gardens (Figs. 1 and 2). Vigour and regenerative capacity of survivors in burnt stands are reduced and soil erosion can become a significant problem.

3. In small remnant stands domesticated and feral pigs can completely destroy regeneration of Araucaria and adversely affect the health of maiden stand trees, such as can be seen in the sacred Araucaria grove in the Kurumul area of the western highlands of Papua New Guinea.

4. Industry in some areas has reduced large stands of this conifer to small pockets of remnant regeneration. Sometimes these logged areas are occupied by gardens and the small population of survivors is reduced further in size.

   This situation can deteriorate further with termite infestation to which hoop pine is susceptible, and as seed viability declines rapidly without storage at 12°C, there is no reserve of dormant seeds in the soil under natural stands; replacement of destroyed or logged mature stems must wait for any existing seedlings to reach reproductive age which commences around age 15 years.

5. There are signs that some stands are over-mature and in some of these there is little or no regeneration due to low seed vigour and viability or destruction of cones by cockatoos, animals and insects.

Potential Value:

Araucaria cunninghamii is one of two species of Araucaria indigenous to New Guinea. It is also indigenous to north-eastern Australia. It is an important tree for the saw milling and plywood industry in Papua New Guinea and has potential for wood pulp and chips.

A number of New Guinea provenances of A. cunninghamii have been tested together with Australian provenances in south-east Queensland and found to produce greater DBHOB than Australian provenances (Reilly, 1974) while in north Queensland, observation plantings suggest that Papua New Guinea hoop pine can produce greater volumes than the Australian hoop pine. In New Guinea the Australian hoop provenances are inferior in growth to those of Papua New Guinea and it is likely the New Guinea hoop provenances will be better than Australian hoop pine in adaptability and productiveness in other tropical countries.

Protective Measures Taken and Measures Recommended:

A number of reconnaissance and seed collecting trips were made from 1972 to 1975, to assess tree characteristics, accessibility of stands, size of cone crops, best time for cone collection, and to collect seed if available.

The reconnaissance of Araucaria stands covered sections of the south-east of Papua, the Morobe Province, Eastern, Western and Southern Highlands Provinces, and the West Sepik Province of Papua New Guinea and the Arfak mountains of West Irian.

Successful seed collections were made in the Morobe and the three highlands provinces of Papua New Guinea and an unsuccessful but informative attempt was made in West Irian (see Forest Genetic Resources Information no.6).

Seedlings of six Papua New Guinea provenances have been raised to establish small conservation stands, and a provenance trial has been recently planted at Bulolo to test four provenances.

These are as follows:

1. Bulolo    - lat. 7°13'S, long. 146°45'E, alt. 1 158 m a.s.l.
   Rainfall (p.a.) 1 615 mm.

2. Elaro      - lat. 7°27'S, long. 146°47'E, alt. 1 500 m a.s.l.
   Rainfall ± 1 880 mm.

3. Bumbu   - lat. 6°42'S, long. 147°00'E, alt. 1 219 m a.s.l.
   Rainfall ± 1 916 mm.

4. Pimaga - lat. 6°30'S, long. 143°30'E, alt. 750 m a.s.l.
   Rainfall 3 405 mm.

Further collections are required from the Milne Bay Province covering the northern slopes of Mt. Nelson and Fergusson Island; in the Papuan province near Mt. Oberee, Woitape and Mt. Suckling; in the Morobe Province from Paiawa; in the Chimbu Province from the Tua River and Chuave; in the Western Sepik Province from Oksapmin; Telefomin and Wutung; in West Irian from Anggi lakes; Arfak Mts., Babor, Japen Island, Sausapor and other accessible areas ¹.

Cultivation:

Seedlings can be raised by the pregermination technique as used for klinkii pine or by sowing into beds. These techniques are adequately covered by such publications as “Technique for establishment and maintenance of hoop pine” (Qld. For. Dept. 1963); the handbook “Silvicultural Techniques in Papua New Guinea Forest Plantations” (Dept. Primary Industry Office of Forests, Papua New Guinea). “Fast growing Timber Trees of the Lowland Tropics No.3 - The Araucarias” (Ntima; Comm. For. Inst. Oxford, 1968) and “Pregermination techniques for Araucaria hunsteinii” (Papua New Guinea Dept. Forests, Trop. For. Res. Note SR27 Howcroft, 1974).

Araucaria cunninghamii can be successfully grafted by using scion budding (patch grafting) with material taken from the apical leader of the main stem, or by side approach grafting and bottle grafting using the apical shoot of the main stem. Grafted branch material produce plagiotropic grafts and have little use other than for pollen production.

SELECTED BIBLIOGRAPHY

Aubreville, A. 1965 Les Reliques de la flores des conifères tropicaux en Australia et Nouvelle Caledonie. Adansonia 5: 481 – 492.

Cameron, M.A. 1958 The flowering and fruiting of Hoop pine (Araucaria cunninghamii). Queensland Naturalist 16: 23 – 26.

Dallimore, W. and Jackson, A.B. 1966 A handbook on coniferae. 4th ed. pp. 111 – 114.

Francis, W.D. 1970 Australian Rain-Forest Trees. 3rd ed. Australian Government Publishing Service, Canberra. pp. 60 – 65.

Gausson, H. 1970 Les Gynmospermes actuelles et fossiles 20: 30 – 34.

Gibbs, L.S. 1916 A contribution to the Phytogeography and Flora of the Arfak Mts. pp. 83 – 84.

Gray, B. 1974 Distribution of Araucaria in Papua New Guinea. P.N.G. Dept. Forest Research Bulletin No. 1 pp. 1 – 56.

Gray, B. 1975 Size composition and regeneration of Araucaria stands in New Guinea. J. Ecol. 63: 273 – 289.

Havel, J.J. 1971 The Araucaria Forests of New Guinea and their regenerative capacity. J. Ecol. 59: 203 – 214.

Higgins, M.D. 1969 Grafting of Hoop Pine in Queensland. Queensland Forest Dept. (Limited publ.) pp. 1 – 76.

Howcroft, N.H.S. 1974 Pregermination Technique for Araucaria hunsteinii P.N.G. For. Dept. Trop. Res. Note SR27 pp. 1 – 10.

Just, T. 1964 Araucariaceae. In. “Encyclopedia americana” 2: 134 – 137.

Lauterbach 1913 Beitrage zur Flora Von Papuasien II Engl. Bot. Jahrb. pp. 50 – 51.

McAlpine, J.R., Keig, G. and Short, K. 1975 Climatic Tables for Papua New Guinea. C.S.I.R.O. Aust. Land Use Research Technical Paper No. 37: 1 – 177.

Ntima, O.O. 1968 The Araucarias. Fast growing timber trees of the lowland tropics 3: 1 – 14, 24 – 59.

Reilly, J.J. 1974 Geographic variation of Hoop Pine. Dept. For. Qld. Res. Paper No.4.

Fig. 1.   Portions of a natural hoop pine stand at Oksapmin, West Sepik province. The stand was severely damaged by fire in 1972. (Photographed September 1975).
	Fig. 2.   The result of 25 years of shirting agriculture. Agaun, Milne Bay province. (Photographed October 1974).

¹ See article on Exploration and Provenance Seed Collection in Papua New Guinea, by N.H.S. Howcroft in Forest Genetic Resources Information no.8