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| Native Conifers of Western TasmaniaTasmania possesses a large number of plant species that occur nowhere else in the world. Our rainforest and alpine communities are particularly significant habitats for these endemic plants. One group of plants occurring in these habitats, the native conifers, is of particular botanical significance. The conifers evolved and became the dominant land plants during the era of the dinosaurs. Many of Tasmania’s conifers are very primitive. In most places conifers have been replaced in importance by flowering plants. Tasmania is one of the few places in Australia where these primitive species can be easily seen. Conifers have also played an important part in Tasmania’s convict and industrial history.
(None of Tasmania's conifers are strictly pines, that is, belonging to the genus Pinus. The common names, whilst resulting from a misappropriation of this word, are too embedded in common use to be changed.)
 The Huon pine (Lagarostrobos franklinii) derives its common name from the stands which once occurred along the Huon River, itself named after Huon de Kermandec, commander of the French ship, L'Esperance. The species is restricted to western and southern Tasmania, where it is largely confined to riverine habitats. The value of Huon pine timber for boat building and furniture making led to the establishment of the pining industry very early in the history of European settlement of Tasmania. Convicts at Macquarie Harbour harvested Huon pines along the Gordon River and built ships at Sarah Island.
Estimates of the area of living Huon pine vary, but are in the order of 10 500 ha. In addition there are about 800 ha of standing, fire-killed pine. The current area of remaining pine is the remnant of a much wider original range that has been reduced by fire, inundation, logging and mining. Today, the remaining stands are well protected within reserves, the majority being within the World Heritage Area .
Although extremely slow growing, the tree may attain heights of over 40 m. Growth rates average a mere 1mm in diameter per year, but can vary from 0.3 mm to 2 mm, depending on conditions. Huon pine can reproduce both vegetatively (from fallen individuals) and by seed. Seed dispersal is largely limited to the area downstream from riverine stands.
The Huon pine can reach prodigious ages, often in excess of 2000 years, making it among the longest-lived organisms on Earth. Only the bristle-cone pine of North America exceeds it in age. International headlines were made with the discovery of a stand of Huon pines on Mt Read that was widely quoted as being in excess of 10 000 years of age. All the individuals in this population are genetically identical, and are all males. The stand arose from one or a small number of individuals, and has maintained itself by vegetative reproduction. It is important to remember that no individual tree in the Mt Read stand is 10 000 years old (in fact, most if not all stems are less than 1000 years old) - rather, the stand itself has been in existence for that long.
 The celery-top pine (Phyllocladus aspleniifolius) is so named due to the resemblance of its 'leaves' to those of celery. In fact, these are not true leaves, but rather cladodes (flattened stems); although the seedlings of this plant produce true needle-like leaves that are replaced by the adult 'cladodes' as it grows. Needle leaves have a small surface area for light reception and the evolution of the flat wide cladodes is thought to be an adaptation to the low light levels in wet forest and rainforest where this species lives. The tree grows to 30 m in height and may attain an age of 800 years. The seeds of this plant are dispersed by birds. Young trees are often found growing in clusters around the base of tall old eucalypts that have survived a fire and are preferentially used by birds for roosting. Birds are attracted to the fleshy red ‘aril’ that is produced below the seed of the celery-top pine, which is also enclosed by in a fleshy white sheath.
Today this slow-growing tree is exploited as a by-product of clearfelling in mixed forests and is commonly used for external cladding and poles in the building industry.
The king billy pine (Athrotaxis selaginoides) is thought to derive its common name from the Tasmanian Aborigine William Lanney, who was referred to as 'King Billy'. It reaches a height of 40 m and may reach ages in excess of 1200 years. The species is largely restricted to regions above 600 m where it grows in highland rainforest. It is one of the most cold tolerant trees in Tasmania.
 A close relative of the king billy pine, the pencil pine (Athrotaxis cupressoides), is generally restricted to sub-alpine areas above 800 m. Like its relative, it can reach ages greater than 1200 years and is one of the most frost hardy trees in Tasmania. The seeds of this tree and king billy have a dispersal distance of less than the height of the parent tree. These species do not produce seed every year but, instead, certain climatic triggers produce a synchronous seeding event when most trees produce large quantities of seed. These ‘mast years’ occur once every 5 years on average..
Pencil pines are often seen around the shores of highland lakes and tarns, creating a fairyland mien of unparalleled beauty.
Compare the leaves of the pencil pine, king billy pine and Laxifolia (a hybrid between the two).
 Tasmania's native conifers are highly susceptible to fire. In certain areas of the state, extensive stands of dead 'stags' give testimony to the ravages of previous fires. Some of the largest pure stands of pencil pine have been lost due to campfires which have escaped. Some species will never recover due to their very slow growth and poor seed dispersal abilities. Indeed, one-third of the State's King Billy pines have been eliminated by fire since European settlement.
The Tasmanian Wilderness World Heritage Area has been declared a "fuel stove only area" in an attempt to prevent the loss of further conifer stands, as well as rainforest and alpine communities, which are also highly susceptible to fire.
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