Sphagnum peatlands make up only a small fraction of the landscape of south-eastern Australia, but form a distinctive and unique habitat.
Sphagnum peatlands usually form in sites of relatively high rainfall and low evaporation, in areas never or rarely subject to drought, and in infertile, anaerobic soils (lacking oxygen). They commonly occur in river valleys, beside lakes and streams or on sandstone shelves, where drainage is hindered. Acidity created by Sphagnum deters bacteria and fungi which would otherwise decompose the dead material, allowing peat to build up. The high watertable and mossy vegetation of Sphagnum peatlands result in a fragile ecosystem sensitive to disturbance. Current threats to the long-term survival of Sphagnum peatlands include draining for agriculture, frequent burning, peat mining and unsustainable moss harvesting.
In Tasmania, Victoria and New South Wales, Sphagnum moss tends to die if it dries out in summer suggesting that Sphagnum peatlands in south-eastern Australia may be near their climatic limits. If so, global warming is likely to reduce their chances of long-term survival.
Sphagnum peatlands occur in New South Wales, the Australian Capital Territory and Victoria, usually between 300 and 1500 m elevation. Tasmania's largest area of Sphagnum lies between 600 m and 1360 m.
The amount of Sphagnum moss in Australia is very small, compared to Northern Hemisphere countries, South America and New Zealand. For example, the total area of Sphagnum peatlands in Tasmania is approximately 1300 ha (or 0.0015%, see map). Most of this resource (>90%) lies within State Reserves and is unavailable for harvesting. This has put pressure on remaining peatlands.
Conservation and management
Sphagnum moss is extensively used by the horticultural industry. Its water-holding capacity makes it a useful potting medium, favoured by orchid growers and often used to wrap rose and fruit tree rootstock for transportation. At present all Sphagnum harvesting in Australia takes place from natural (i.e. wild) populations. However, growth trials of Sphagnum moss in glasshouses have begun in New Zealand, which may eventually lead to commercial growing.
S. cristatum is the most common species in Australia, and the most widely harvested, although S. australe and S. subsecundum are also regularly harvested.
The Department of Primary Industries and Water provides guidelines for the sustainable use and management of Sphagnum moss.