Edition 2 From Forest to Fjaeldmark The Vegetation Communities Rainforest and related scrub Eucryphia lucida Edition 2 From Forest to Fjaeldmark (revised – May 2018) 1 Rainforest and related scrub Community (Code) Page Athrotaxis cupressoides-Nothofagus gunnii short rainforest (RPF) 10 Athrotaxis cupressoides open woodland (RPW) 12 Athrotaxis cupressoides rainforest (RPP) 15 Athrotaxis selaginoides-Nothofagus gunnii short rainforest (RKF) 17 Athrotaxis selaginoides rainforest (RKP) 19 Athrotaxis selaginoides subalpine scrub (RKS) 21 Coastal rainforest (RCO) 23 Highland low rainforest and scrub (RSH) 25 Highland rainforest scrub with dead Athrotaxis selaginoides (RKX) 27 Lagarostrobos franklinii rainforest and scrub (RHP) 29 Nothofagus-Atherosperma rainforest (RMT) 31 Nothofagus-Leptospermum short rainforest (RML) 34 Nothofagus-Phyllocladus short rainforest (RMS) 36 Nothofagus gunnii rainforest scrub (RFS) 39 Nothofagus rainforest (undifferentiated) (RMU) 41 Rainforest fernland (RFE) 42 General description Diselma archeri and/or Pherosphaera hookeriana. These are mapped within the unit Highland This group comprises most Tasmanian vegetation coniferous shrubland (HCS), which is included within dominated by Tasmanian rainforest species (sensu the Highland treeless vegetation section. Jarman and Brown 1983) regardless of whether the dominant species are trees, shrubs or ferns. Rainforests and related scrub vegetation generally Tasmanian cool temperate rainforest has been occur in high rainfall areas of Tasmania that exceed defined floristically by Jarman and Brown as "... an average rainfall of 50 mm in the driest month communities dominated by species of Nothofagus, (Read and Brown 1996). They occur from sea level Atherosperma, Eucryphia, Athrotaxis, up into the treeless subalpine areas below the Lagarostrobos…, Phyllocladus or Diselma." climatic treeline, which varies from around 800 m in However, the authors note that some Tasmanian the south-west of the state to around 1400 m in the rainforest may also be dominated by species more central north-east (Kirkpatrick 1997). They are commonly found as part of the rainforest generally confined to areas topographically understorey. Hence vegetation dominated by protected from fire. Rainforest ecology and species usually considered rainforest understorey succession has been discussed in detail elsewhere plants such as Anodopetalum biglandulosum, Richea (for example Brown & Podger 1982, Jarman, Brown pandanifolia or Dicksonia antarctica are also included & Kantvilas 1984, Read 1985, Brown 1988, Read & in mapping units described in this section as Hill 1988a & b, Jarman, Kantvilas & Brown 1994, Rainforest and related scrub. The only rainforest Read 1995, Brown & Read 1996). communities not included within mapping units belonging to this section are those dominated by Edition 2 From Forest to Fjaeldmark (revised – March 2021) 2 Vegetation mapped in this section vary greatly in sparse, while ground ferns may vary greatly in structure and include closed forest, woodland, scrub, abundance. Callidendrous forest in lowland shrubland, heathland and fernland. The scope of the situations is usually tall (over 30 m) but reduces in state-wide survey and classification of Tasmania's height with increasing elevation. Thamnic rainforest rainforest vegetation by Jarman et al. (1984) was is of moderate height (sometimes reaching 30 m) limited to forests over 8 m in height. Because of the with an understorey that, while relatively open, more limited scope of their vegetation classification contains a distinct layer of tall shrubs. The ground and the restrictions imposed by available mapping fern Blechnum wattsii is usually present although methods the classification of mapping units within varies in abundance, while tree ferns are usually the TASVEG Rainforest and related scrub group absent or rare. Implicate rainforest is usually short does not align precisely with the state-wide (less than 20 m) with an uneven canopy that is not classification of rainforest by Jarman et al. (1984), distinctly separated from the tangled understorey of although there is overlap. woody shrubs and climbers below. The sixteen mapping units included within the group Rather than using the three structural categories Rainforest and related scrub are defined by their used by Jarman et al. (1984) to describe most canopy dominants and structural characteristics, with lowland rainforests, both RFA mapping and TASVEG their habitat characteristics providing further mapping distinguish only two. The tall forests with assistance with discrimination. Substrate productivity, large crowns and clear separation between canopy proximity to the coast and elevation are particularly and understorey are mapped as Nothofagus- significant in determining the appropriate mapping Atherosperma rainforest (RMT) in TASVEG and M+ unit. by the RFA. This mapping group includes some of The canopy may comprise a single layer of relatively the thamnic forest types described by Jarman et al. uniform height or may include a taller (emergent) (1984); those in which the forests are tall and the layer of rainforest species varying in cover from shrubby understorey more open. These typically sparse to more densely spaced. There is never more have greater amounts of Atherosperma moschatum, than 5% cover of emergent non-rainforest species in which may be dominant, and less Phyllocladus the canopy. aspleniifolius and Eucryphia lucida. They occur in higher productivity sites. Beneath the canopy layer/s, rainforest communities vary greatly in their structure, some having a Rainforests lacking a clear separation between the distinctive sub-canopy or mid layer of tall shrubs and canopy and understory and characterised by smaller small trees, in which immature stages of the canopy crowned trees are usually mapped in TASVEG as tree species are often present. Most rainforest Nothofagus-Phyllocladus short rainforest (RMS) and species are characterised by having a continuous in the RFA as M-. This group includes many of the recruitment strategy, although many still rely on implicate forests of Jarman et al (1984) and the canopy gaps for their successful establishment. shorter, denser forms of thamnic forest. These forests typically have a greater abundance of Rainforests that are not distinguishable based on key Phyllocladus aspleniifolius and Eucryphia lucida and indicator species or habitat rely more heavily on occupy lower productivity sites. differences in structural attributes. These forests are commonly dominated by Nothofagus cunninghamii TASVEG mapping diverges from both the RFA with varying amounts of Atherosperma moschatum, classification and Jarman et al. (1984) in its treatment Eucryphia lucida and/or Phyllocladus aspleniifolius in of highland rainforests and rainforest scrub. In the canopy. TASVEG, rainforest lacking key indicator species and typically shorter than 12 m (although less commonly Jarman et al. (1984) also used structural up to 18 m) in highland areas above 900 m are characteristics to differentiate communities within mapped as Highland low rainforest and scrub (RSH) Tasmanian rainforests. Of importance, three terms regardless of structure. These forests may extend to ‘callidendrous’, ‘thamnic’ and ‘implicate’, were used lower elevations where productivity is poor, as to describe rainforest structure. They described indicated by the key to this section. callidendrous rainforest as having an open, shady understorey in which Dicksonia antarctica and Coastal rainforest (RCO) lacks key indicator species epiphytic ferns are usually common and shrubs but is distinguished floristically by the dominance of rainforest taxa other than Nothofagus cunninghamii Edition 2 From Forest to Fjaeldmark (revised – March 2021) 3 (e.g. commonly Atherosperma moschatum, General management issues Eucryphia lucida or Phyllocladus aspleniifolius), the Overall, rainforest and related scrubs are adapted to prominence of tall broadleaf wet forest trees in the low disturbance levels and are self-sustaining under understorey such as Pomaderris apetala, Olearia natural levels of localised disturbance such as tree argophylla and/or Nematolepis squamea and its fall. Any increase in this disturbance acts to change proximity to the coast. the forest structure and floristic composition (Cullen Rainforest areas that have not yet been 1991). Changes in forest type and structure can differentiated into one of the available mapping units result from human disturbance in rainforest (Calais & are allocated to the mapping unit Undifferentiated Kirkpatrick 1983). rainforest (RMU). These forests are most likely to be Fire is a significant threat with many rainforest eventually attributed to either RMS, RMT or, if species being killed outright by even low-intensity occurring at elevations above 900 m, to RSH. fire. Other species may re-sprout; however, repeated fires, even decades apart, will result in Section revision significant change in the vegetation, which will take Prior to the release of TASVEG 3.0 in 2013, a from decades to centuries to recover (Cullen 1991, review of scrub vegetation in TASVEG led to Cullen & Kirkpatrick 1988, Jackson 1968). Significant vegetation previously mapped as Leptospermum areas (32%) of Athrotaxis selaginoides rainforest with rainforest scrub (RLS) being recoded as have been eliminated by wildfire since European Leptospermum with rainforest scrub (SRF) and arrival, most since 1880 (Brown 1988). Athrotaxis included within the Scrub, heathlands and coastal