Scientific name: Araucaria bidwillii Hooker 1843

Synonyms: Columbea bidwillii (Hook.) Carrière, Marywildea bidwillii (Hook.) A.V.Bobrov & Melikyan

Common names: Bunya-bunya, Bunya pine

Description

Tree to 40(-50)m tall, with trunk to 1.5 m in diameter, free from branches for most of its height in dense stands or more or less clothed with replacement branches in the open. Bark brown to nearly black, smooth, thick, peeling in thin layers but some flakes accumulating as short, horizontal lines of warts. Crown conical at first, becoming broadly dome-shaped above and sometimes with additional, irregular dome-shaped crowns contributing to an overall cylindrical outline beneath the main crown with tiers of four to seven (or more) very slender, elongate branches bearing tufts of branchlets only at and near their tips. Branchlets remaining green for several years, widely spaced out to the sides of the supporting branches and densely clothed with but not hidden by the foliage. Leaves sword-shaped on sterile branches, standing straight out from the twigs or angled a little forward, more or less all gathered to the sides by twisting of the petioles, 2-5 cm long, 5-10 mm wide, very unequal in length along the branchlets, stiff, very dark green above, paler beneath, ending in a long, stiff point. Leaves more densely arranged on the uppermost and fruiting branches, shorter, often only 2 cm long and curved inward. Stomates aligned with the long axis of the leaf, in more numerous discontinuous lines beneath than above. Pollen cones to (4-)10-15(-20) cm long, 1.2-1.5 cm thick, each pollen scale with 10-12 pollen sacs in two rows. Seed cones very large, nearly spherical to a little elongate, 25-30 cm high, 20-25 cm wide, weighing up to nearly 5 kg, with as many as 150 seeds. Seed scales to 6.5 cm long and 7 cm wide, broadly winged on either side of the embedded seed, markedly tapered at the apex, with an upturned, triangular free tip about 6 mm long. Seeds nearly pear-shaped, 5-6 cm long and 2.5 cm wide, edible. Cotyledons remaining in the seed coat underground during germination.

Australia, along the coast of Queensland. Forming pure stands or mixed with hoop pine (Araucaria cunninghamii) and evergreen hardwoods as an emergent above coastal montane rain forest; (150-)1,000-1,200 m. Annual precipitation is 1,100-1,400 mm in the southern area, with heavy rains in summer but with a dry season from April/May to September. In contrast to this, the northern populations lie close to the wettest part of the Australian continent, causing a more evenly distributed annual precipitation of 1,500-2,000 mm

Conservation Status

Red List Category & Criteria: Least Concern

The extent of occurrence (EOO) is approximately 11,000 km2 with 99% of this in southeastern Queensland. Although the EOO is within the threshold for Vulnerable, Araucaria bidwillii is known from more than 10 locations and the population is not considered to be severely fragmented. Although significant past decline has occurred within the last three generations it has not been possible to quantify its extent. No significant decline in EOO, AOO, quality of habitat, number of locations or subpopulations or number of mature individuals is currently evident or predicted in the near future. On this basis, Araucaria bidwillii is assessed as Least Concern. Although the overall assessment is Least Concern, the subpopulations at Mt Lewis and Cannabullen Falls contain few individuals and are very restricted in their extent and as such, are highly susceptible to stochastic events such as fire. Genetic analysis indicates that these northern subpopulations are highly distinctive and there is a potential threat from outbreeding depression due to the widescale planting of ornamental and amenity trees that have originated from the southern subpopulations. The isolated northern subpopulation has less than 100 mature individuals. Genetic investigations indicate that this population differs significantly from those in the south and that its conservation should be a priority. Southern subpopulations range in size from a few tens of trees to over 1,000. They are likely to be the remnants of an almost continuous larger population that stretched from the coastal areas into the Bunya Mountains (Pye 2004). Araucaria bidwillii is a large, emergent tree in subtropical rainforest on basaltic or other igneous substrates that is sometimes associated with Araucaria cunninghamii. It occupies the ecotone between moist angiosperm-dominated forest and drier vine thickets with partly deciduous trees, particularly in the southern part of its disjunct range. The forest is divided into larger and smaller woods by ‘balds’, coarse grasslands or open savannas which form sharp boundaries with the forest patches. Abundant seed is produced in ‘mast years’ at approximately three-year intervals. Seeds remain in the cone until after it falls off the tree; they may be dispersed by water flowing in creeks and gullies, rolling down a slope or by animal vectors such as the Mountain Brush-tail Possum, Trichosurus caninus (Smith et al. 2007). Despite significant exploitation in the past, the main subpopulations in southern Queensland are not currently threatened. In some areas regeneration and expansion into disused pastoral and farming areas is occurring and the majority of the subpopulations are within protected areas. The subpopulations at Mt Lewis and Canabullen Falls contain few individuals and are very restricted in their extent and as such, are highly susceptible to stochastic events such as fire. Genetic analysis indicates that these northern subpopulations are highly distinctive and there is a potential threat from potential outbreeding depression due to the widescale planting of ornamental and amenity trees that have originated from the southern subpopulations. The indigenous people of southern Queensland (and northern New South Wales) considered this species to be sacred and their edible seeds (or nuts) were, and still are, a ceremonial food of great significance. The forests were the focal point of major seasonal ceremonial gatherings that brought together thousands of people from a wide area (Huth and Holzworth 2005). Early European settlers in Queensland harvested trees for their good quality timber that was used in cabinet making and construction. Some attempts were made to establish plantations but these were largely unsuccessful. Araucaria bidwillii is widely planted as an ornamental. The majority of the remaining subpopulations and locations are within protected areas. One of these, the Bunya Mountains National Park, was the second national park to be established in Queensland, in 1908.

References

Farjon, A. (2010). A Handbook of the World's Conifers. Koninklijke Brill, Leiden.
Eckenwalder, J.E. (2009) Conifers of the World: The Complete Reference. Timber Press, Portland.
IUCN Red List of Threatened Species, International Union for Conservation of Nature and Natural Resources. Cambridge, UK /Gland, Switzerland