Tasmanian Heathlands

In Tasmania and Australia heaths are not dominated by members of the Ericaceae as in the northern hemisphere, but by members of the closely related family Epacridaceae and other taxa particularly Leptospermum (Myrtaceae). There are eight species of Leptospermum in Tasmania four of which are endemic. Heaths dominated by the endemic Leptospermum glaucescens occur in the west and wetter parts of the southeast and commonly include other shrubby species such as Bauera rubioides, Leptospermum scoparium and L. nitidum. Also in the southeast, especially on the Freycinet Peninsula, the endemic Leptospermum grandiflorum forms heath-like communities sometimes in association with Hakea rostrata. Leptospermum lanigerum is another heath forming species confined to slightly wetter soils in the north and east, but extends from sea level to the sub alpine zone. Along the coast there are various dune heath communities in which several endemic shrubs may be encountered including Epacris barbata (Epacridaceae), Eriostemon virginatus (Rutaceae), Pultenaea diffusa (Fabaceae) and the endemic herb Stenopetalum lineare (Brassicaceae). In much wetter areas where the water table lays close to the surface for long periods a kind of wet heath can be found that is transitional between sedgelands and dry heath and know locally as sedge heath. Here the main scrub species are of include Epacris lanuginosa, Leucopogon australis and L. collins (Epacridaceae), and there may be several endemic shrubs like Baeckia leptocaulis (Mrytaceae), Epacris corymbiflor, E. gunnii (Epacridaceae) and Oschatzia saxifraga (Apiaceae). The herbaceous elements may include Calorophus minor, Gymnocephalus sphaerocephalus, Hypolaena fastigiata, Leptocarpus tenax and Lepyrodia scariosa.

Heaths in the more, demanding, alpine conditions found on the plateaus are composed of various combinations of mainly endemic species such as Bellendena montana, Orites acicularis, O. revolute, Persoonia gunnii (Proteaceae), Cyathodes petiolaris, Monotoca empetrifolia, Richea scoparia (Epacridaceae), Helichrysum backhousei and Olearia ledifolia (Asteraceae). The plateaus also have a number of gymnosperm dominated heath-like communities, which are unique to Tasmania. Microcachrys tetragona (Podocarpaceae) is a decumbent or semi-erect species that forms tangled heaths either carpeting the ground in pure stands or in association with Pentachondra pumila and the endemic Cyathodes dealbata (Epacridaceae). Other heath-forming endemic conifers on the plateaus are Diselma archeri (Cupressaceae) and Microstrobus niphophilus (Podocarpaceae). These can form very dense heath-like communities either individually as local dominants or in association. In more sheltered habitats they can assume shrub proportions. At slightly lower altitudes, in the sub alpine belt, heath also occurs within woodlands, especially on talus slopes or in areas affected by cold air drainage. Species more typically found in these situations are again largely represented by endemics such as Lomatia polymorpha (Proteaceae), Richea sprengeloids (Epacridaceae) and Westringia rubrifolia (Lamiaceae).

Tasmanian Sedgefields

Sedgefields dominated by Carpha alpina, Oreobolus oumilio and Uncinnia flaccida (Cyperaceae) occur on all of the higher mountains of Tasmania. They occupy soils that are occasionally waterlogged but may dry out during dry summers.  Their swards may be closed or open but are often dotted with various dwarf shrubs such as Hakea lissocarpus, Lissanthe montana, Olearia algida and the endemic Pernettya tasmanica (Ericaceae). Cushion plants may also be present especially Pimelea pygmea and the endemic Abrotanella fostorioides (Asteraceae). At lower altitudes, sedges may be less dominant and, in fact, Astelia alpina of the Liliaceae is the dominant species over extensive areas of waterlogged soils often forming pure stands.

References

Barlow, B. A. 1981. The Australian Flora: its origin and evolution. In: Flora of Australia. Volume 1. Introduction. Bureau of Flora and Fauna.  Australian Government Publishing Service, Canberra.

Beadle, N. C. W. 1981. The Vegetation of Australia. Gustav Fischer Verlag.

Burbidge, N. T. 1960. The phytogeography of the Australian region. Australian Journal of Botany, 8: 75-212.

Curtis, W. 1967. The endemic flora of Tasmania. The Ariel Press, London.