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| Tasmania's Cool Temperate Rainforest
|Species of the Rainforest|
 Tasmania contains Australia's largest tracts of cool temperate rainforest, covering around 10% of the State. Cool temperate rainforest is very different from rainforest found in warmer climates. Unlike tropical and warm temperate rainforests, the trees do not have large buttresses, there are no palms, and climbing plants are rare in Tasmania’s rainforest.
Cool temperate rainforest is a verdant,silent, cool, dark and damp place where both the trunks of trees and the forest floor are usually festooned with a luxuriant carpet of mosses and lichens. In autumn and early winter in particular, the rainforest floor is dappled with an array of brightly coloured fungi.
Defining Tasmania's cool temperate rainforest is difficult, partly because it can grow in so many different habitats. However, there are generally three things to look out for:
Tasmania’s rainforest is characterised by three factors: - Most rainforest occurs in areas receiving over 1 200 mm of rain a year, but some isolated patches occur in damp gullies in drier areas;
- It is dominated by particular trees, such as myrtle, leatherwood, celery-top pine, sassafras, Huon pine, pencil pine, King Billy pine or deciduous beech maybe important in some areas; and
- Species living in rainforest don't require disturbance, such as fire, to reproduce, and are generally disadvantaged by disturbance, which allows in light-dependant, short-lived competitors.
Tasmanian rainforest contain some species with an ancestry dating back to the super continent of Gondwana, and have been present in Tasmania for more than 60 million years. They evolved well before the species that dominate what we call "sclerophyll vegetation" (like eucalypts and acacias). Particularly ancient genera with fossil and pollen evidence to support their presence and evolution within Tasmania include Agastachys, Athrotaxis, Anopterus, Archeria, Bellendena, Cenarrhenes, Dicksonia, Eucryphia, Phyllocladus, Microcachrys, Microstrobos, Nothofagus, Orites, Lomatia, Tasmannia, and Telopea.
Tasmanian rainforest grows in many different places and in many different ways. There are four main types: callidendrous (tall park-like rainforest with an open understorey); thamnic (rainforest with a shrubby understorey); implicate (short tangled vegetation); and, montane (woodlands and forest at high altitude). The distribution of these various types is largely controlled by soil fertilityand altitude.
Where fire has burnt the vegetation eucalypts may occur as emergents over a rainforest understorey, such forest is referred to as mixed forest. If there is a cover of less than 5% eucalypts over a rainforest understorey then the vegetation is termed rainforest. More More eucalypts than this means it is defined as mixed forest.
Tasmanian rainforest is such a quiet place that sometimes it seems that there are no animals. Of course there are many, but generally there is a smaller variety of vertebrate animals and they are fewer in number (compared with other forests). Mammals include the Tasmanian long-tailed mouse, ringtail possum, pademelon, spotted-tailed quoll and dusky antechinus. Twenty-one species of native birds regularly visit rainforest, including the black currawong, green rosella, olive whistler and grey goshawk. Of the reptiles, the Tasmanian tree frog, tiger snake and brown skink are relatively common. Tasmanian rainforest contains some of the most ancient and primitive representatives of invertebrates. Some of these include the large land snail, Macleay's swallowtail butterfly, freshwater crayfish and the peripatus, or velvet worm.
The greatest threats to rainforest are from human activities and fire. The land that rainforest grows on is often wanted for other uses, such as for agriculture, forest plantations, dams and mining.
In the last century over seven per cent of Tasmanian rainforest was burnt. Following fire, rainforest vegetation may pass through several seral stages and if left undisturbed for long enough will return to mature rainforest. If fires are cool and the vegetation long unburnt then some rainforest trees may survive and most species will regenerate successfully from soil stored seed and seed dispersed from nearby areas. However some very fire sensitive rainforest species, such as the conifers King Billy pine and pencil pine, may be eliminated by a single fire event and have no means of recovering.
Another threat to rainforest is from pests and diseases. Myrtle wilt is a serious but natural fungal disease which kills mature myrtles, especially where there has been some form of disturbance. Phytophthora root rot (Phytophthora cinnamomi), can also be a problem at the edge of rainforest, along roads or following fire. Normally rainforest soils are too cool to support this pathogen but where the canopy is opened by disturbance soils temperatures can be warm enough to allow this pathogen to disease susceptible rainforest species.
There is a lot of competition for the use of Tasmanian rainforest and the land it grows upon. Many of its trees are highly valued by the craftwood industry for their utility and aesthetic appearance; Huon pine, myrtle, celery-top pine and sassafras are best known. However, because rainforest trees grow slowly, it is not economical at present to grow them in plantations, and their future long-term supply is uncertain. At present, there are export embargos on Huon and King Billy pine. The salvage from hydro-electric impoundments of long-dead Huon pine logs satisfies much of the current demand, but this resource is not renewable.
Rainforest is also used by bee keepers to produce leatherwood honey, and of course, rainforest is very popular with tourists. All of these uses must be carefully managed if we are to maintain rainforest for future generations.
 The most extensive areas of callidendrous rainforests occur in Tasmania's north-west, though it is also found throughout the western half of the State, and in patches in the north-east highlands. Much of the rainforest of the north-west lies outside reserves. Tiny patches of rainforest also survive in some east coast gullies where extra moisture from clouds or streams make up for the low rainfall. About 41% of rainforests are in the Tasmanian Wilderness World Heritage Area (TWWHA). The best examples of implicate and thamnic rainforests which are richer in endemic species occur in the TWWHA. Another 25% of rainforests occur in other reserves around the state.
There are a number of excellent trails that will give you more understanding (and a real rather than virtual experience!) of our cool temperate rainforest. The Creepy Crawly Trail in the Southwest National Park is well worth visiting, as is the Franklin River Nature Trail in the Wild Rivers National Park. There are also excellent walks through rainforest at Cradle Mountain and Lake St Clair, as well as at Liffey Falls at the northern edge of the Tasmanian Wilderness World Heritage Area. Visit the Parks and Wildlife Service web site at www.parks.tas.gov.au to find out more about these walks.
Forestry Tasmania also have some excellent, interpretive walks through rainforest, such as those at Weldborough Pass in the north-east, Sandspit and Tahune in the south-east and the Julius River Rainforest Walk in the north-west.
Notesheet - Tasmanian Rainforest
Contact: Biodiversity Conservation BranchBiodiversity Conservation Branch
Department of Primary Industries, Parks, Water and Environment
134 Macquarie Street
HOBART TAS 7000
Phone: 03 6233 6556
Fax: 03 6233 3477
Email: Wildlife.Reception@dpipwe.tas.gov.au
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