Sites 24

Research sites were located in lowland remnant woodland and forest stands across the lower Derwent Valley, Coal Valley and Midlands of Tasmania (collectively called the Midlands from here on, see figure 1-1). The study area was low altitude (below 470m), low rainfall (< 700 mm annual average), extending from latitude 41.511° to 42.622°S and longitude 146.958° to 147.984°E. In summer, maximum temperatures average 24°C, whilst in winter most days have frosts, sometimes severe. Thirty sites were studied (Table 2-1) comprising remnant woodland and forest stands which had been exposed to a variety of levels of disturbance and recent fire history. The sites were allocated a priori and equally by number to one of three ranked categories of vegetation condition namely healthy, intermediate and poor according to the following features (adapted from Keighery (1994):

 healthy – all expected plant layers present and healthy, very light to moderate levels of grazing and wood collection, any disturbance confined to small areas, few or localised exotic species

 intermediate – shrub and ground layer present but reduced of simplified, moderate to heavy levels of grazing and wood collection, apparent change in soil structure, exotic species cover up to 50% of area

 poor – plant community severely altered, evidence of heavy to extreme grazing, predominantly paddock trees in pasture. Most poor sites were less than 500m away from other more substantial remnant patches and were usually separated from them by fencing.

Sites were rated for levels of disturbance caused by grazing as light (< 1 dry sheep equivalent (DSE)), moderate (1-2 DSE), heavy (2-4 DSE) and extreme (>4 DSE). Their recent fire history (within last 10 years) was obtained from land managers of each site (Table 2.1). Four sites were publicly owned reserves, five private reserves and the rest on privately owned unreserved land. Six sites were near Bothwell and one in Elderslie in the Derwent Valley (Eucalyptus tenuiramis woodland), eight sites were near Oatlands in the southern Midlands (E. pauciflora /E. viminalis woodland) and twelve sites were in the northern Midlands, eight near Epping Forest (E.

amygdalina/ E. viminalis woodland) and four near Fingal (E. amygdalina/ E. viminalis woodland). Three sites were in the Coal valley near Campania (E. amygdalina/ E. viminalis woodland), see Figure 1-1. The sites at Oatlands and Bothwell had all been previously established for research reported by Davidson et al (2007), two sites at each of Epping Forest, Fingal and Oatlands were measured prior to restoration treatments being undertaken as part of a trial reported in Chapter 5 of this thesis and four others were measured prior to a seedling microsite study reported in Chapter 3. The other sites were chosen to ensure a range of a priori remnant condition was sampled across a broad geographical range in the Midlands.

Table 2-1 Thirty sites with site name abbreviation, location, a priori health class, disturbance level, recent fire history, dominant eucalypt species and TASVEG

community (Harris and Kitchener 2005) that have been measured to provide base data for a structural complexity index for Tasmanian dry forests/woodlands

Site(abbreviation)  Location  Class  Disturbance  Fire history  Canopy dominant  TASVEG  

Ellis Private Reserve (BOTH)  Bothwell  Healthy  Light  burnt 2005  E. tenuiramis  DTO  Humbie Hill Private Reserve (HH)  Bothwell  Healthy  Moderate  burnt 2002   E. tenuiramis  DPD  Elderslie Nature Reserve (ELD)  Elderslie   Healthy  Light  burnt 2006  E.tenuriamis  DTO  Gravelly Ridge Conservation Area (GR)  Campania   Healthy  Light  burnt 2002  E. tenuiramis  DTO 

Lowdina Regrowth (LR)  Campania   Healthy  Moderate  unburnt  E.amygdalina  DAS 

Western Tom Gibson Reserve  (WTG)  Epping Forest   Healthy  Light  unburnt  E.amygdalina  DAZ  Tom Gibson Reserve Burnt (TG)  Epping Forest   Healthy  Light  burnt 2003  E.amygdalina  DAZ  Barton Farm Private Reserve (B)  Epping Forest   Healthy  Moderate  burnt 2004  E.amygdalina  DAZ 

Evercreech coupe (EC)  Fingal   Healthy  Light  unburnt  E.amygdalina  DAM 

Radio Mast Hill, Plot 1Weedings (W1)  Oatlands  Healthy  Light  unburnt  E.pauciflora  DPO  Meaburn Peratta Tip Reserve , (MPT)  Oatlands  Intermediate  Moderate  unburnt  E.pauciflora  DPO  Humbie Intermediate (HI)  Bothwell  Intermediate  Moderate  unburnt  E. tenuiramis  DPD  Campbell Intermediate (CI)  Bothwell  Intermediate  Heavy  burnt 2005  E. tenuiramis  DTO 

Lowdina Simple (LS)  Campania   Intermediate  Heavy  unburnt  E.amygdalina  DAS 

Downey Valleyfield remnant (DD)  Epping Forest   Intermediate  Heavy  partially burnt  E.amygdalina  DAZ  Osbourne remnant (O)  Epping Forest   Intermediate  Moderate  unburnt  E.amygdalina  DAZ  Evercreech plantation remnant (ED)  Fingal   Intermediate  Heavy  unburnt  E.amygdalina  DAM  Meaburn Liliesleaf remnant (M)  Oatlands  Intermediate  Heavy  unburnt  E.pauciflora  DPO  Weedings Plot 2 Bald Hill (BH)  Oatlands  Intermediate  Heavy  unburnt  E.pauciflora  DPO 

Weedings Plot 3 (W3)  Oatlands  Intermediate  Heavy  unburnt  E.pauciflora  DPO 

Campbell Paddock Tree (CPT)  Bothwell  Poor  Extreme  burnt 2005  E. tenuiramis  DTO 

Humbie Paddock Tree (HPT)  Bothwell  Poor  Extreme  unburnt  E. tenuiramis  DPD 

Downey Paddock Tree 1 (DPT1)  Epping Forest   Poor  Extreme  unburnt  E.amygdalina  DAZ  Downey Paddock Tree 2 (DPT2)  Epping Forest   Poor  Extreme  unburnt  E.amygdalina  DAZ  Downey Paddock Tree 3 (DPT3)  Epping Forest   Poor  Extreme  unburnt  E.amygdalina  DAZ  Evercreech Paddock Tree 1 (EPT1)  Fingal   Poor  Extreme  unburnt  E.amygdalina  DAM  Evercreech Paddock Tree 2 (EPT2)  Fingal   Poor  Extreme  unburnt  E.amygdalina  DAM  Oatlands Paddock Tree 1 (PT1O)  Oatlands  Poor  Extreme  unburnt  E.pauciflora  DPO  Oatlands Paddock Tree 2 (PT2O)  Oatlands  Poor  Extreme  unburnt  E.pauciflora  DPO  Oatlands Paddock Tree 3 (PT3O)  Oatlands  Poor  Extreme  unburnt  E.pauciflora  DPO 

The remnants measured in this study fell into six TASVEG vegetation communities (Table 2-1) all within the same vegetation type called “Dry Eucalypt Forest & Woodland Vegetation” (Harris and Kitchener 2005). The TASVEG benchmarks for the six vegetation communities were very similar in their structural components with the main differences being in their expected species complements. All the

communities measured were therefore combined in the same structural complexity index. The effectiveness of this decision was tested through statistical analyses (see section 2.2.5).

Stands of paddock trees were included in this study, and thus incorporated into the Tasmanian index, because they are important biological legacies in the landscape and they account for a substantial amount of remnant woody vegetation cover in lowland areas that have been significantly cleared for agriculture (Gibbons and Boak 2002; Gibbons et al. 2008b; Manning and Fischer 2010). Scattered paddock trees provide ecosystem functions such as habitat at the local and landscape scale and may be foci for restoration efforts in the future (Reid and Landsberg 2000; Manning et al. 2006).