Category Archives: New South Wales

Reconstructing Western Sydney Grassy Woodland Understorey at Hoxton Park, Sydney, NSW

By Christopher Brogan

Purpose of the project. Endeavour Energy sought to restore a small highly disturbed Cumberland Plain Woodland bushland remnant at the West Liverpool Zone Substation at Hoxton Park, to offset 12 native trees removed to facilitate construction works at their electricity substation.

Condition of the site. The Cumberland Plain Woodland remnant was very small (approx.0 3.ha) and contained relatively healthy examples of four native trees (Grey Ironbark Eucalyptus crebra, Grey Box E. moluccana , Forest Red Gum E. tereticornis and some Paperbark Melaleuca decora). However, the native shrub and ground layer was generally absent and the soil surface was highly compacted with a low organic matter content. This was due to historic clearing for agriculture, recent clearing for the installation of electrical infrastructure and the fact that a layer of coarse fill material and asphalt had been deposited over the topsoil in some areas (probably for car parking).

Goals. As we found fragments of 3 grasses and 6 forbs remaining on site, our goals were to protect and enhance all remaining plants by ecologically sensitive weed control and planting of missing species from the Cumberland Plain Woodland community.

We had 24 months to achieve the revegetation, with performance criteria being: a survival rate of >80%; a reduction in the percentage cover weed to < 5%; and, an increase in percentage cover of the herbaceous layer to 67% – 100%.

Fig 1. Weed control included cut stump poisoning of woody weeds and high volume herbicide spraying of invasive perennial grasses.

Fig 1. Weed control included cut stump poisoning of woody weeds and high volume herbicide spraying of invasive perennial grasses. (Photo C Brogan)

Around 260 cubic metres of recycled wood waste was used to mulch to a depth of 100mm over 2,600 square metres.

Around 260 cubic metres of recycled wood waste was used to mulch to a depth of 100mm over 2,600 square metres.(Photo C.Brogan)

What we did. We identified two zones on site: Zone 1 – with capacity for assisted regeneration; and Zone 2 – without capacity for assisted regeneration. Zone 1 was treated using standard bush regeneration techniques – i.e. removal of weed to facilitate natural regeneration. Zone 2 treatments included: weed control, mulching with recycled wood waste (2,600m2 x 100mm deep); planting with 9,100 native tubestock (3-4 plants /1m2) raised from Western Sydney seed; and watering throughout the first month.

After some assisted natural regeneration and planting 9,100 native tubestock (raised from Western Sydney seed) a strong cover of native understorey was reinstated.

After some assisted natural regeneration and planting 9,100 native tubestock (raised from Western Sydney seed) a strong cover of native understorey was reinstated. (Photo. C Brogan)

The Presentation Title

Same part of the site taken before and after treatment.

Same part of the site taken before and after treatment. (C Brogan)

What advice can we offer?

  • Always check your project site to identify any fragments of native species which may be present and protect them during weed control works, particularly when spraying herbicide.
  • Use good quality tubestock of the appropriate provenance and budget for a seed collection program if the project timetable allows.
  • Never underestimate the need to water tubestock during hot months and allocate sufficient resources to watering.

Contact: Christopher Brogan, Earth Repair and Restoration Pty Ltd, PO Box 232 Panania NSW 2213. Tel: +61 (0)2 9774 3200 Email: chris@earthrepair.com.au; Web: www.earthrepair.com.au

Acknowledgement. This is summarised from a talk first presented to the symposium ‘Rebuilding Ecosystems: What are the Principles?’ Teachers’ Federation Conference Centre, November 13th, 2014, Australian Association of Bush Regenerators (AABR).

 

 

Twelve years of healing: Rehabilitating a willow-infested silt flat – Revegetation

Alan Lane

Key words: weed management, National Park, headwall, instability, Salix

The site: Popes Glen Creek is a small permanent stream rising in Memorial Park, Blackheath New South Wales, Australia. It flows through Popes Glen Bushland Reserve and the Greater Blue Mountains World Heritage Area (GBMWHA), joining the Grose and Hawkesbury/Nepean River systems. The upper catchment drains a significant sector of the urban township of Blackheath.

The problem: Decades of erosion from surrounding unsealed roads resulted in a 1ha silt flat forming at the headwaters of the creek and terminating in a highly incised headwall 3m high and 20m wide. Upstream, the silt flat and severely braided creek were populated by a dense forest of mature, multi-trunked specimens of Crack Willow (Salix fragilis), as well as thickets of Purple Ossier (S. purpurea), Small-leaf Privet (Ligustrum spp.), Holly (Ilex aquifolium), Cotoneaster (Cotoneaster spp.) and immature S. fragilis. There was also a ground layer of Montbretia (Crocosmia x crocosmiiflora), Blackberry (Rubus fruticosus agg), English Ivy (Hedera helix), Creeping Buttercup (Ranunculus repens) and Honeysuckle (Lonicera japonica).

This dense and complex infestation of weeds threatened to spread downstream into susceptible remote areas of the GBMWHA, where it would rapidly become extremely difficult to remove and would ultimately threaten the Grose and Hawkesbury-Nepean River systems.

Fig 1. Feb 2005 - the creek bank, dominated by weeds prior to work.

Fig 1. Feb 2005 – the creek bank, dominated by weeds prior to work.

Fig 2. Sept 2014 - same site nearly 10 years later, showing established plantings and some natural regeneration.

Fig 2. Sept 2014 – same site nearly 10 years later, showing established plantings and some natural regeneration.

Works carried out: Phase 1: 2002 – 2008  In 2002, the Pope’s Glen volunteer bushcare group, supported by Blue Mountains City Council and funding from the Urban Run-off Control Program, established trial plantings on four sites (100m2 each) to identify a limited range of local riparian and wetland species and the planting techniques best suited to revegetating and stabilising the silt flat. The species included Red-fruit Saw-sedge (Gahnia sieberiana), three teatree species (Leptospermum lanigerum, L. polygalifolium, and L. juniperinum), Broad-leaved Hakea (Hakea dactyloides), and three ferns (Blechnum nudum, B. watsii and Cyathea australis).

A 3-year grant from the Environmental Trust (2005-2008) then enabled a program of weed removal and replanting, encompassing the upstream half of the silt flat and expanding the list of plant species to about 30.

The weeds were removed progressively in a patchwork to preserve the stability of the silt. The willows were killed by stem injection and felled when dead. Over these 3 years, the volunteer group planted approximately 7000 plants and carried out approximately 1200 hours of site maintenance. This has resulted in a diverse and resilient wetland community, with high levels of plant establishment from both planting and from natural recruitment (Figs 1 and 2).

Phase 2: 2012 – 2018 At the commencement of this phase, stability of the downstream portion of the silt flat and headwall was dependent upon the integrity of the roots of the remaining dense stands of weeds. These could be removed only as part of an integrated program of works to stabilise the silt and the headwall. A second grant from the Environmental Trust (2012-2018) is enabling an integrated, 6-year program of stabilisation, restoration and revegetation to be carried out by a team of experienced contractors, using both “soft” and “hard” engineering strategies.

The volunteer group is responsible for on-going site maintenance, photography, monitoring surface water quality and water table depth and quality, and for surveying vegetation, macro-invertebrates, frogs, birds and stygofauna.

Overall results. The formerly highly degraded silted flat is now a thriving community of wetland and riparian vegetation, home to a rich diversity of small birds, dragonflies and mayflies. Frogs are beginning to populate the site. Water quality has been significantly improved, with up to 85% of faecal coliforms and 75% of nitrate-N removed in the wetland. This improves the water quality in Popes Glen Creek and reduces the pollutant load into the GBMWHA.

Fig 3. Feb 2013 - a portion of the headwall viewed from downstream. (Plunge pool approx.3m below. (Image Damon Baker www.nomadgraphics.com.au).

Fig 3. Feb 2013 – a portion of the headwall viewed from downstream. (Plunge pool approx.3m below. (Image Damon Baker http://www.nomadgraphics.com.au).

Fig 4. Nov 2014 - same site showing heavy retaining wall and spillway now constructed. (Plunge pool has been stabilised with rock armouring.)

Fig 4. Nov 2014 – same site showing heavy retaining wall and spillway now constructed. (Plunge pool has been stabilised with rock armouring.)

Lessons learned and future directions: This is an example of how an apparently overwhelming challenge can be tackled by a dedicated group of volunteers with critical mass, commitment and longevity, provided that the group has support from a body such as a local Council and that it can raise funds to employ skilled assistance as needed. It is anticipated that the ambitious program of rehabilitating the extensive and highly degraded silt flat will be completed within the life of the present grant.

Stakeholders and funding bodies: This work is supported by a grant from the Government of New South Wales through its Environmental Trust and by the Blue Mountains City Council. Unless otherwise stated, photographs have been provided by Alan Lane and Paul Vale.

Contacts: Dr Alan Lane, Coordinator Popes Glen Bushcare Group, PO Box 388, Blackheath NSW 2785, Australia. Ph +61 2 4787 7097; Paul Vale, Deputy Coordinator Popes Glen Bushcare Group, 81 Prince Edward St, Blackheath NSW 2785, Australia. Ph +61 2 4787 8080; and Ray Richardson, Chairman of Steering Committee, Environmental Trust Grant 2011/CBR/0098. Ph +61 2 4759 2534.

Cooks River Naturalisation, Sydney, NSW Australia

By Dan Cunningham

Key words: riparian rehabilitation, revegetation, reconstruction

document

A reach of the Cooks River prior to and after naturalisation

A reach of the Cooks River prior to and after naturalisation

Sydney Water have undertaken a project to convert 1.1km of concreted sections of the Cooks River, Sydney Australia, to a more natural state, substantially improving their potential for aquatic function and the provision of services to surrounding residential areas.

The problem and its causes. Seven kms of the highly urbanised Cooks River were concrete lined in the 1940s in an effort to alleviate flooding and reduce water pollution. Since that time the natural values of the river have declined due to pollution and lack of riparian remnant vegetation.

Community interest in the quality of the environment had increased since the 1940s and, the structure of the concrete began to significantly deteriorate, in 2014 Sydney Water removed sections of deteriorated concrete and undertook environmental rehabilitation of parts of the riparian zone.

Fig 2. Cooks River Naturalisation sites

Fig 2. Cooks River Naturalisation sites

What we did. Between 2007 and 2013 Sydney Water carried out a masterplanning exercise that included asset inspections, hydraulic analysis, stakeholder consultation and concept design development; in order to identify sites along the river that were suited to renewal and naturalisation (Fig 2).

There was little adjacent native vegetation on which to base the design of the revegetation work, but local botanical surveys had resulted in a conceptual map of the catchment’s pre-existing ecological communities, which allowed the project to select species suited to four different habitat types:

  • Freshwater and Brackish Swamp – Lower to mid bank (non- tidal reach) and constructed wetland
  • Clay Plain Scrub Forest – mid bank to upper bank and over bank areas (reference – Third Avenue remnant)
  • Turpentine Ironbark Forest – Selected larger trees
  • Coastal Saltmarsh – Lower to mid bank (tidal reaches) and saltmarsh benches (reference Gough Whitlam Park and Wolli Ck)
Fig 3. Presumed ecological communities prior to clearing

Fig 3. Presumed ecological communities prior to clearing

Fig. 4. Profile of bank treatment

Fig. 4. Profile of bank treatment

Fig 5. Concrete lining of

Fig 5. Concrete lining of

 Results. The project resulted in the reconstruction of a diversity of native riparian habitat types and improved connectivity for biota between reaches of the river that were previously disconnected. This resulted in massive aesthetic improvement, with local residents conveying much improved local area pride and positivity. The project provides a social amenity, with the provision of pathways, seating, interpretive signage and provides an opportunity for local communities to reinstate a sense of place and reconnect with each other in the context of a natural river. In addition it represents value for money considering that longer asset life produced by the natural system.

Fig 6. Works inlcuded floodways devoid of trees.

Fig 6. Works inlcuded floodways devoid of trees.

Fig 7. Native vegetation now stabilising the  banks.

Fig 7. Native vegetation now stabilising the
banks.

Acknowledgement: This summary was first presented to the Symposium ‘Reubilding Ecosystems’ held at the Teachers’ Federation Conference Centre, Sydney by the Australian Association of Bush Regenerators (AABR)

Contact: Dan Cunningham – Program Lead, Waterways Sydney Water, Email: <daniel.cunningham@sydneywater.com.au>

Websites:

http://www.sydneywater.com.au/SW/water-the-environment/what-we-re-doing/current-projects/stormwater-management/stormwater-naturalisation/index.htm

http://www.sydneywatertalk.com.au/crbnp/

Acknowledgement. This is summarised from a talk first presented to the symposium ‘Rebuilding Ecosystems: What are the Principles?’ Teachers’ Federation Conference Centre, November 13th, 2014, Australian Association of Bush Regenerators (AABR).

Constructed Saltmarshes in two urban sites, Kooroowall Reserve and Gough Whitlam Park, Sydney, Australia

By Mia Dalby-Ball

Key words: Wetland, Saltmarsh, Intertidal, Urban Ecology, Construction

Introduction: Coastal Saltmarsh is an intertidal ecosystem under threat and currently listed on both the state (New South Wales (NSW)) and Australia’s national list as an Endangered Ecological Community. Saltmarsh provides a variety of ecosystem services, including providing habitat for crabs which then release larvae during some high-tides. Crab larvae from saltmarshes have been found to be key food for small fish.

Over 80% of urban saltmarshes in NSW have been filled for a range of uses including playing fields, often after their use as rubbish dumps. With an increase in awareness of the value of these ecosystems, the restoration of saltmarsh in urban areas is occurring globally and locally. Here we describe two saltmarsh reconstruction projects at Kooroowall Reserve and Gough Whitlam Park, Sydney.

Aim of the works. In each example the aim was to create a functioning saltmarsh – that is a saltmarsh with appropriate tidal inundation, appropriate plant species and cover and invertebrate species (e.g. crabs, molluscs).

Works undertaken. In both cases works commenced with soil testing (soil type, pollutants, acid sulfate soils and depth to ground water) followed by the development of a detailed design.   Hydrology was observed from surrounding areas to identify location-specific elevations connected to nearby existing intertidal areas. Substrate was then excavated to the desired level, top-soil was put in place to provide appropriate nutrients, then planting carried out and/or natural regeneration encouraged.

Figure 1. Reconstructed saltmarsh at Kooroowall Reserve, 2015

Figure 1. Reconstructed saltmarsh at Kooroowall Reserve, 2015

Figure 2.  Gough Whitlam Park January 2015 in 2m tide. (Photo M. Dalby-Ball)

Figure 2. Gough Whitlam Park January 2015 in 2m tide. (Photo M. Dalby-Ball)

Results to date. Around 80% cover of saltmarsh plant species has established and persists at both sites to date. (Figs 1 and 2.) Non-saltmarsh plants dominate the upper 5m of the Gough Whitlam Park as this was not excavated low enough, with a similar area occurring at the Kooroowall Reserve saltmarsh (Fig 3). Saltmarsh crabs and gastropods are present at both sites. Density of saltmarsh plants at both sites is greatest where the tidal inundation is most frequent. The before and after images show the dramatic change from a weed dominated, neglected area of fill (Kooroowall reserve) to Saltmarsh and from Turf (GWP) to Saltmarsh.

Natural regeneration and establishment of saltmarsh plants was highest where there was “wrack” covering the exposed sandy substrate. (Wrack is organic material such as washed up sea-grass or a mix of leaves fine twigs.) That is, saltmarsh seedlings that germinated in areas without wrack were found to die during consecutive hot dry days while those in wrack generally survived.

Figure 3. Kooroowall Saltmarsh January 2015. (Photo: M. Dalby-Ball)

Figure 3. Kooroowall Saltmarsh January 2015. (Photo: M. Dalby-Ball)

Lessons learned. Lessons include the importance of achieving the required tidal inundation. In both examples the level of some sections of the sites could have been lowered at the time of construction. In the case of Kooroowall an area of heavy clay was encountered and additional resources would have been required to implement the planned works. As the resources were not available, this was not done. The higher area now has Coastal Wattle growing on it, shading out the saltmarsh. There is now either a reoccurring cost to remove this plant, or if nothing is done, that area becomes terrestrial vegetation.

Fencing was found to be essential at the Kooroowall Saltmarsh as its proximity to a children’s play area resulted in it becoming a de facto bike jump area. No fencing was required at Gough Whitlam Park; however there is a high level of community engagement and interpretive signage.

It is likely that the wrack was beneficial in retaining moisture to assist survival of species.

Acknowledgements: Both Saltmarsh creation projects were facilitated and managed through local government. Kooroowall by Pittwater Council and Gough Whitlam Park by Canterbury Council. Both projects had grant funding (over 50%) from federal government sources distributed through the then Catchment Management Authorities. These agencies have now changed name to Local Land Services. Dragonfly Environmental designed the Saltmarsh re-creation and Gough Whitlam Park.

Contact: Mia Dalby-Ball, Director, Ecological Consultants Australia, 30 Palmgrove Road Avalon Beach Sydney NSW, 2107, Tel: +61 488 481 929, Email: ecologicalca@outlook.com

Acknowledgement. This is summarised from a talk first presented to the symposium ‘Rebuilding Ecosystems: What are the Principles?’ Teachers’ Federation Conference Centre, November 13th, 2014, Australian Association of Bush Regenerators (AABR).

Directly transplanting of native monocots from donor areas to suitable reconstruction sites

By Edgar Freimanis

Key words: urban bushland restoration, site remediation, direct return topsoil, plant salvage, transplanting.

Introduction: As a bush regeneration contractor often working adjacent to development sites in the Sydney Region it occurred to me that plants and topsoil earmarked for destruction at a development site could be salvaged and translocated to improve results in nearby or similar restoration areas. Monocots lend themselves to this process due to their comparatively shallow, fibrous and stoloniferous root systems that have adapted to regrowing after disturbance.

Works undertaken and results. Over the years our bush regeneration contract team has translocated monocots at a range of project sites where natural regeneration potential is very low. Typically this technique accompanies our more conventional planting of nursery grown tree and shrub tubestock in these areas. The soils in these recipient areas are usually similar to those of the donor sites from where they were sourced. If weed management is needed, the recipient sites are typically weeded before transplanting takes place. We use hand tools such as shovels to dig-up variable sized sections of mostly native grasses and some other native monocotyledonous plant sods from areas that have been designated for development and other similar authorised clearing.

The sods are placed into plastic trays, moved and directly transplanted into parts of adjoining bushland conservation areas that have been designated for reconstruction planting. The transplants can be placed within recipient sites at similar densities to grassy ground layer tubestock plantings, (e.g. at densities of between 1-4-plants per m2, or more) or laid out like turf in continuous sections,

Plant establishment aids such as water retention crystals and fertilisers are also applied to each transplant at planting to assist with plant survival and establishment. The transplants are watered-in initially and on subsequent occasions, depending on prevailing soil moisture conditions, project resources and project timing.

Ongoing follow-up bush regeneration weeding is typically undertaken in the recipient sites, as required. (Fig 1). Monitoring has been confined to ‘before and after’ photo documentation, as shown in the following examples.

Figure 1. A sod of the native grass Entolasia stricta being transplanted at 4 plants/m2 into the old driveway at the Tuckwell Road. (Photo: Ecohort)

Figure 1. A sod of the native grass Entolasia stricta being transplanted at 4 plants/m2 into the old driveway at the Tuckwell Road. (Photo: Ecohort)

1. Tuckwell Road, Castle Hill Shale Sandstone Transition Forest and Sydney Turpentine Ironbark Forest Regeneration and Reconstruction of low residence sections. The recipient site was a rehabilitated old bitumen driveway within an estimated 0.40-hecatre bushland conservation and restoration area Native grasses and other monocots were transplanted from a bushland area that was being cleared for associated road widening works at a density of four plants/m2. (Figs 2 and 3).

Figure 2. Tuckwell Road ‘before’ (note: exotic plants already removed). (Photo: Ecohort)

Figure 2. Tuckwell Road ‘before’ (note: exotic plants already removed). (Photo: Ecohort)

Figure 3. Tuckwell road about 2-years later showing transplanted native monocots and planted native shrubs. (Photo: Ecohort)

Figure 3. Tuckwell road about 2-years later showing transplanted native monocots and planted native shrubs. (Photo: Ecohort)

2. Kellyville (Cumberland Plain Woodland site). The recipient site consisted of an edge of a bushland conservation area, that was subject to earthworks associated with a retirement village development. The recipient site’s soils were ripped to alleviate compaction and topsoiled with local clay-based topsoil. Native grass sods were transplanted from donor areas that were located within the approved development footprint area adjoining the bushland conservation area. The sods were cut into 200-300mm sections and placed in close proximity to on-another, not too dissimilar to a jig-saw puzzle or hand cut turf, to make a continuous grassy layer, with minimal gaps between transplanted sods. The transplanted sods were lightly filled and top-dressed with local topsoil to fill and level out any gaps between the sods, and then trimmed to surrounding ground levels and watered-in well. (Figs 4 and 5)

Figure 4. Native grasses being transplanted, very close together like turf sods at Kellyville. (Photo: Ecohort)

Figure 4. Native grasses being transplanted, very close together like turf sods at Kellyville. (Photo: Ecohort)

Figure 5. Same Kellyvillle site about a year later. (Photo: Ecohort)

Figure 5. Same Kellyvillle site about a year later. (Photo: Ecohort)

3.Spinifex transplanting on coastal sand dunes. In this project the rhizomous native grass sprinfex was transplanted into dunes from nearby areas at Corrimal Beach in the Wollongong local government area, as a part of works associated with Council’s 2013 Dune Management Implementation Plan. The spinifex transplanting works were undertaken in conjunction with weed control and tubestock reconstruction planting works.(Figs 6 and 7)

Figure 6. Spinifex being transplanted into a section of dune at 2-4-plants per m2. (Photo: Ecohort)

Figure 6. Spinifex being transplanted into a section of dune at 2-4-plants per m2. (Photo: Ecohort)

Figure 7. Section of spinifex that has established from previous transplanting. (Photo: Ecohort)

Figure 7. Section of spinifex that has established from previous transplanting. (Photo: Ecohort)

Benefits and characteristics of direct transplanting include:

  • Reduction of lengthy plant propagation and seed collection phases;
  • Avoidance of seed maturity restrictions and clashes with project construction phases;
  • Guaranteed achievement of local provenance material;
  • Ability to obtain species that are difficult to propagate or collect seed from;
  • Potential inclusion of other plant species from donor to recipient sites (translocated as seed in the soil of transplanted sods);
  • Achievement of similar densities to tubestock planting or turf-laying;
  • Ease of implementation (transplanting monocots is a technique that has been long-practiced by bush regenerators, gardeners and horticulturists);
  • Ability to conduct the treatments on a small scale using hand tools, or large scale using heavy machinery.

Barriers and challenges to direct transplanting include:

  • Timing/gaining consent difficulties relating to compatibility of works between donor and recipient sites;
  • Convincing consent authorities of the efficacy of this method;
  • Technical issues: proximity of donor and recipient sites;
  • Cost, (including maintenance and watering) which can be higher than other methods;
  • Difficulty in transplanting some monocots;
  • Potential for soil pathogen spread.

Acknowledgements:  This summary was originally presented to the November 2014 Symposium ‘Rebuilding Ecosystems’ held at the Teachers’ Federation Conference Centre, Sydney by the Australian Association of Bush Regenerators (AABR)

Contact: Edgar Freimanis, Ecohort, ( PO Box 6540 Rouse Hill NSW Australia 2156 Tel: +61 418 162-970 Email: ed @ecohort.com)

Acknowledgement. This is summarised from a talk first presented to the symposium ‘Rebuilding Ecosystems: What are the Principles?’ Teachers’ Federation Conference Centre, November 13th, 2014, Australian Association of Bush Regenerators (AABR).

Bourkes Gorge Spoil Dump #2 Restoration – Kosciuszko National Park

 Elizabeth MacPhee and Gabriel Wilks

Bourkes Gorge Spoil Dump #2 is one of two large spoil dumps created during construction of the Murray 1 Pressure Tunnel between 1962 and 1966 to carry water from the Geehi Reservoir to the Murray 1 Pipelines.  These pipelines deliver water to the Murray 1 Power Station on the western side of Kosciuszko National Park near the township of Khancoban.  At this site during Scheme construction, approximately 300 000 m3 of unconsolidated rock spoil was removed from the tunnel access point on a rail siding and dumped in the steep valley of a tributary creek flowing to Bogong Creek.

 The site prior to rehabilitation. Bourkes Gorge Spoil Dump #2 was one long unstable rock slope devoid of native vegetation with scrap metal, timber and concrete jutting out along erosion scars. It was too steep to stand on, with a slope height of 60m and an angle of approximately 380. The spoil dump was 150m wide across the valley and extended about 250m upstream, blocking the tributary creek. As a result, an 8m washout scar was left in the southern side of the spoil dump with continual erosion down the creek, eroding particularly during peak flows.

Fauna and vegetation surveys were conducted on and in the surrounding forest. Three fauna species listed as vulnerable under the NSW Threatened Species Conservation Act 1995 (TSC Act) were identified in the surrounding forest – the Yellow-bellied Glider Petaurus australis, Gang-gang Cockatoo Callocephalon fimbriatum and the Eastern False Pipistrelle Falsistrellus tasmaniensis. (Schultz, M unpublished). Habitat requirements for nesting and roosting of these species did not occur within the site.  The Spotted Tree Frog Litoria spenceri is listed as Critically Endangered by the International Union for Conservation of Nature (IUCN) and is also listed in the Federal Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and the TSC Act. This species was known to occur in the vicinity of site, but surveys had recorded a dramatically declining population (Hunter & Gillespie 1999). It was not recorded on or around the site during the fauna survey in 2008. Weeds such as Blackberry (Rubus sp.) and willow (Salix spp.) occurred at the top edge of the site and minimal vegetation was found on the majority of the spoil.

Objectives of the restoration works :

  • Re-shaping the spoil dump to a more stable slope.
  • Constructing an environment that favoured revegetation and habitation of site-indigenous flora and fauna species.
  • Integrating the site into the surrounding tall montane forest
  • Constructing a channel to enable high water flow events to move across the site without scouring or rendering the site unsafe.
  • Slowing high flow events to limit the scour effects on the downstream environment.
  • Safely managing contamination or general construction waste found at the site

Treatments. Works were undertaken from December 2009 to April 2010. Stabilisation works consisted of reshaping the spoil dump and lining 300m of artificial creek line. The resulting land form was planted with 50,000 tubestock in 2010 – 2011 and had specific management practices applied to minimise potential impact on the Spotted Tree Frog.

Plant species used in the revegetation had to be sourced from plants as cuttings, seed or division from the surrounding environment, capable of being commercially propagated due to the number required, and robust enough to withstand the more extreme conditions found on site than in surrounding forest. One rare species Bertya findalyii was found colonising the edge of the site and so was incorporated into the planting list.

Results.

Erosion Control.  The rehabilitation of the Bourkes Gorge #2 spoil dump resulted in 43,300 m3 of rock soil being re-shaped to reduce slope and direct water flow, reducing the potential for surficial erosion and mass slumping. Slope angles were reduced from around 38ْ to between 26ْ and 30ْ  (URS, 2009). Around 560M3 of concrete reinforced with structural synthetic fibre and on site rock was used to form the water channel. In the three years since rehabilitation, there have been two major flood events in the region – October 2010 and March 2012. The Jagungal weather station in Kosciuszko NP recorded 6, 12 and 24 hour duration rainfall intensities exceeding the 100 year Average Recurrence Interval (ARI) intensity. There was no evidence of erosion or slumping at Bourkes Gorge Site following these events.

Revegetation.  Assessment of the vegetation was done two years after planting by Greening Australia Capital Region using BioMetric (http://www.environment.nsw.gov.au/papers/BioMetricOpManualV3-1.pdf).  This monitoring has shown outstanding survival and growth rates – with 35% cover by 19 native species, with virtually nil weed. (Species are listed in Table 1 ).

Lesson learned: Rock spoil in high altitude, steep conditions with no organic matter in a compacted and unstable condition will not naturally revegetate, even if left for a fifty year period.  Applying site appropriate techniques such as re-shaping for stability, allowing for water flow, moving compacted rock to create air pockets and allow water infiltration, and adding the essential ingredients of organic matter, nutrients and plant material can trigger successful site revegetation. Covering the ground with a layer of organic matter such as rice straw ameliorates temperature extremes on site, allowing young seedlings to survive and flourish.

Acknowledgements. Thanks are extended to the restoration team at Kosciuszko National Park, including the many contractors who participated.  We also thank Nicki Taws and Angela Calliess (Greening Australia Capital Region) who undertook the formal vegetation monitoring.

 

After earthworks, planting niches are filled with compost

After earthworks, planting niches are filled with compost

Main slope at Bourkes Gorge #2 spoil dump

Main slope at Bourkes Gorge #2 spoil dump

Liz MacPhee pictured at Bourkes spoil dump one year after planting

Liz MacPhee pictured at Bourkes spoil dump one year after planting

Table 1. Vegetation data recorded on a 50m transect approximately 2 years after treatment.  (Data from Greening Australia Vegetation Monitoring Former Snowy-Hydro Sites Kosciuszko National Park).

Scientific name

Common name

Tube stock

Direct seeding

Transplants from within site

Trees  

 

 

 

Eucalyptus dalrympleana Mountain Gum

X

   
Eucalyptus delegatensis Alpine Ash

X

X

 
Eucalyptus globulus v bicostata Southern Blue Gum

X

   
Eucalyptus viminalis Manna Gum

X

   
Lomatia fraseri Tree Lomatia

X

   
Shrubs  

 

 

 

Acacia dealbata Silver Wattle

x

   
Acacia melanoxylon Blackwood wattle

X

   
Bedfordia arborescens Blanket leaf

X

   
Bossiaea foliosa Leafy Bossiaea

X

   
Bertya findlayii Alpine Bertya

X

   
Cassinia longifolia Shiny Cassinia

X

   
Coprosma hirtella Rough Coprosma

X

   
Coprosma quadrifida Prickly Currant Bush

X

   
Daviesia mimosoides subsp. laxiflora Mountain bitter pea  

X

 
Helichrysum stirlingii Ovens Everlasting

X

   
Kunzea ericoides Burgan

X

   
Leptospermum grandiflorum Mountain Tea Tree

X

   
Leptospermum obovatum River Tea Tree

X

   
Polyscias sumbucifolia Elderberry Panax

X

   
Pomaderris aspera Hazel Pomaderris

X

   
Prostanthera lasianthos Mint bush

X

   
Forbs  

 

 

 

Derwentia derwentiana Derwents Speedwell

X

   
Dianella tasmanica Mauve Flax lily      
Senecio linearifolius Tall Senecio

X

   
Stellaria pungens Prickly starwort

X

   
Ferns        
Polystichas proliferatum Mother Shield-fern

X (divisions)

   
Blechnum spp. fern    

X

Grasses  

 

 

 

Poa ensiformis  

X

X

 
Poa  helmsii Broad leafed snow grass

X

X

 
Poa sieberiana Tussock grass

X

X

Yarrangobilly Native Seed and Straw Farm

Elizabeth MacPhee and Gabriel Wilks

Yarrangobilly Caves is a tourist destination within Kosciusko National Park (KNP), New South Wales. The Yarrangobilly Caves Wastewater Treatment Plant (WTP) has been established to treat greywater produced at the tourist centre, to stop nitrogen moving into the limestone karst system of the caves.

To optimise benefits from the WTP, the Rehabilitation team undertook the planting of locally native grass species in the discharge area, with a view to producing seed and weed-free mulch for use in the KNP Former Snowy Sites restoration program.

Effluent is initially treated using a bacterial blivet and then undergoes an ultra-violet treatment process so that it is within a “greywater” classification. It is then stored in a 200,000 litre tank and released under pressure to a discharge area. Prior to being discharged the effluent is diluted with fresh water to an average ratio of 7:3 (effluent:fresh water) in order to reduce the total nitrogen in the irrigated water to around 10 mg/L, which has been used as a threshold figure for nutrient loading. Once at the right concentration, the effluent is discharged in a large flat sedimentary rock area of about 1 ha in size.  The irrigation area in which the plant species are grown is approximately 0.5 ha.

Vegetation treatments. From 2006 to 2010, some 20,000 plants of a number of species of the grass genus Poa were planted in the discharge area of the WTP, at 50cm spacings (Fig 1).  The four main species were: Poa costiniana; P. fawcettiae, P. sieberiana and P. ensiformis; all native to KNP. Over the last 6 years, more than 300 kilos of highly viable Poa spp. seed has been collected and used in restoration works across the Park. The thatch (seed heads and cut off straw) has also been harvested and used as mulch on some of the sites.

Other species needed for rehabilitation in KNP have also been planted in the site over the last two years. Bossiaea foliosa and Lomandra longifolia have been grown for seed production and a variety of difficult to germinate shrubs have been grown to provide cutting material for propagation.

Soil sampling and soil treatments. Sampling was conducted prior to and after plant harvest to gauge the soil’s physical and nutrient status.  The samples (10cm cores of topsoil and subsoil) were sent to the Environmental and Analytical Laboratories at Charles Sturt University for analysis of Total Phosphorus and Total Nitrogen. (ammonia and nitrates as Nitrogen and phosphorus as Phosphorus (Bray)).

As early soil tests showed that pH reduced, Lime was applied to the discharge area in 2010 at 1 – 1.5 tonnes to to raise topsoil pH approximately 1 unit.

Results.

Seed and mulch production: Within the first 18 month period, nearly 100 kilos of seed was collected. To date over 300 kilos of highly viable Poa spp. seed has been collected and used in rehabilitation across the park, with the 2011/2012 harvest producing approximately 58 kilograms of seed. In the 2012-12 harvest, an estimated 288 kilograms of thatch was removed for use as mulch in restoration areas in the Park.

Soil fertility. More nitrogen and phosphorus was discharged during the 2011/2012 season than could be removed by plants season, with the native species having naturally low nutrient removal rates. Annual soil monitoring and peizometer monitoring of the ground water is keeping track of the use and movement of nitrogen in this landscape and to monitor any changes in soil chemistry.

 Suggestions for improvements:

  • Review irrigation scheduling to ensure the bulk of irrigation is occurring from November to March when nutrient uptake will be at its highest (rather than in the cooler months).
  • De-thatch the grass species at the start of spring to encourage fresh re-growth and therefore improve nutrient uptake over the spring and summer months
  • Test effluent on a regular basis to assess salt load;
  • Further treat effluent to reduce the nitrogen, phosphorous and sodium load;
  • Monitor and adjust pH as required; and
  • Reseed bare patches to maximise nutrient uptake by plants.

 In 2012 a progressive replacement planting program commenced, where sections of the oldest plants were poisoned and replaced with young plants. This continual renewal replanting will ensure the plantation remains actively growing, taking up maximum levels of nutrient and producing high quality seed and mulch.

Acknowledgements.  Funding for this project came from The Former Snowy Sites Rehabilitation project with soil and plant nutrient data provided by D.M McMahon (2008, 2012): Environmental Monitoring Use of Effluent for Irrigation, Yarrangobilly Caves, NSW. Environmental Consultants (agronomy) Wagga, Wagga.

Yarrangobilly grasses ready for harvesting

Yarrangobilly grasses ready for harvesting

The plantings are mainly four local species of Poa

The plantings are mainly four local species of Poa

Slopes2Summit Bushlinks Project

Keywords – landscape, connectivity, restoration, revegetation, NSW southwest slopes

The Slopes2Summit (S2S) Bushlinks project commenced in August 2012 and is in the first stage of implementing on-ground works to build landscape-scale connectivity across private lands in the southwest Slopes of NSW – from the wet and dry forest ecosystems of the upper catchment and reserves to the threatened Grassy Box Woodlands of the lower slopes and plains (Fig 1.).

Fig 1. Map of the S2S area and priority landscapes for Bushlinks

Fig 1. Map of the S2S area and priority landscapes for Bushlinks

The increasing isolation of plant and animal populations in “island” reserves scattered through an agricultural landscape is a recognised threat to the long term viability and resilience of ecosystems under potential impact of climate change. If we can increase the viable breeding habitat through off-reserve remnant conservation, and increase the habitat for dispersal by increasing connectivity, we may be able to influence the trajectory for some of our species – the Squirrel Glider (Petaurus norfolcensis)) and threatened woodland birds in particular.

The S2S Bushlinks Project is attempting to address connectivity issues through the following approaches:

1. Cross property planning. Foster and encourage cross property planning for habitat connectivity between neighbours, community, Landcare and/or subcatchment groups resulting in more integrated on-ground works projects, and raising awareness of the benefits of connectivity for wildlife.

2. On-ground investment in connectivity. The project is partnering with farmers and land managers to support and encourage fencing and revegetation in strategic places in the landscape with the objective of increasing habitat connectivity.  S2S Bushlinks applies scientific principles to the site assessments and evaluation, which then sets the level of investment in a site.  High scoring sites receive the highest rates of rebate, but the provision of low levels of public investment in sites that may not be of high priority is important for fostering participation in revegetation of any sort to encourage the culture of caring for the land.

Site assessment and scoring for funding level uses the following criteria:

  • Connectivity and landscape value – Does the site link to or create new patches of habitat according to principles of habitat connectivity? (Fig 2)  Is there existing vegetation in 1000ha radius around the site in an optimal range of 30-60%?
  • Area : perimeter ratio – Bigger blocks of revegetation are more cost-efficient and better habitat than linear strips of revegetation, and the project scoring encourages landholder to go bigger and wider in order to qualify for a higher level of funding.
  • Habitat Values – Does the site have existing values like old paddock trees, rocky outcrops or intact native ground layer, and therefore become a more valuable site? Is it in the more fertile, productive parts of the landscape and therefore of more productivity benefit for wildlife as well?
  • Carbon value – The scoring is based on the size of the revegetation and rainfall zone. The CFI Reforestation tool is being used to value the collective potential carbon sequestration of the Bushlinks project.

The emphasis on cross-property planning flows through to the implementation of on-ground works. Landholders are encouraged to work with neighbours and the site evaluation system is used to assess site value without the property boundaries – cooperation makes the site bigger and usually increases the connectivity value, and therefore scores higher.

3. Review and adaptive management process. The site assessment is to be reviewed in July 2013 against the objectives – did it work to prioritise sites well – did we invest wisely? The scientists and experts are then able to work closely with Holbrook Landcare to adjust the project eligibility, assessment and evaluation criteria to continually improve the outcomes in subsequent funding years.

4. Monitoring framework. As part of the in-kind contribution to the project, S2S partners Dr Dave Watson, CSU Albury and Dr. Veronica Doerr, CSIRO are working towards a framework for the long-term monitoring of landscape scale connectivity for continental-scale initiatives like Great Eastern Ranges (GER).  As part of a GER Environmental Trust Project in 2013, an expert panel workshop will be convened to begin this process in 2013.

The framework will then be used to pilot a project-scale design for Bushlinks, which will allow us to measure ecological outcomes.

Bushlinks will contribute to the Slope2Summit portal of the Atlas of Living Australia, supported by the Slopes2Summit facilitator. To develop community participation in monitoring and evaluation, participants and the wider community will be encouraged to contribute wildlife sightings and other data to the atlas.

The S2S partnership applied for funds through the Australian Governments Clean Energy Futures Biodiversity Fund in 2011 and was successful in the 2011/12 funding year for a six year project. Holbrook Landcare Network is managing the S2S Bushlinks Project on behalf of the Slopes2Summit and the Great Eastern Ranges Initiative, in partnership with Murray CMA.

Contact: Kylie Durant, Bushlinks Project Officer, Holbrook Landcare Network, PO Box 121 Holbrook, NSW 2644 Australia. Tel: +61 2 6036 3121

Fig 2. Summary of the connectivity model outlined in Doerr, V.A.J., Doerr, E. D and Davies, M.J. (2010) Does Structural Connectivity Facilitate Dispersal of Native Species in Australia’s Fragmented Terrestrial Landscapes? CEE Review 08-007 (SR44). Collaboration for Environmental Evidence: www.environmentalevidence.org/SR44.html

Fig 2. Summary of the connectivity model outlined in Doerr, V.A.J., Doerr, E. D and Davies, M.J. (2010) Does Structural Connectivity Facilitate Dispersal of Native Species in Australia’s Fragmented Terrestrial Landscapes? CEE Review 08-007 (SR44). Collaboration for Environmental Evidence: http://www.environmentalevidence.org/SR44.html

Fig 3. Revegetation in the farming landscape in the Southwest Slopes of NSW

Fig 3. Revegetation in the farming landscape in the Southwest Slopes of NSW

 

 

West Hume Landcare Group – Taking stock, 24 years on

Judy Frankenberg

Key words: agricultural landscape restoration, community involvement, salinity, threatened species

The West Hume Landcare Group was formed in 1989 as a community response to land degradation in the area. Funding to employ a coordinator for three years was obtained in 1990. This enabled a high level of project activity in addition to tree planting, including a roadside vegetation survey, farm planning workshops, demonstration sites for ground water recharge and discharge management, and perennial pasture establishment. In the first 5 years of its existence, the group organised nearly 250 different events, attracted funding of over $500,000 and managed 17 different projects.

The second 5 years saw a period of consolidation – then, from late 1997, the employment of a full time project officer enabled  the development of a Land and Water Management Plan.  By early 2000 the Group had attracted a total of $1,000,000 in project funding over 11 years.

“Taking Charge of Recharge” was the largest project undertaken by the West Hume Landcare Group, commencing in 2001. It involved 80 properties, with a total of 170,009 local trees and shrubs planted on 370 ha.  Some 93 ha of remnant vegetation were fenced over the two years of the project. This project was the climax of a very busy 12 years of the Landcare Group’s life, during which 400,000 trees and shrubs were planted in a wide variety of projects across the landcare area – in addition to direct seeding and natural regeneration.  This revegetation had a variety of purposes, including recharge and discharge management, corridor linkages between remnants, vegetation connections specifically designed to strengthen the local (threatened) Squirrel Glider (Petaurus norfolcensis) population, and livestock shelter.

Many of the planting projects initially involved only small numbers of trees, with a low proportion of shrubs.  They were important in giving landholders confidence that tree planting was a credible farm management activity and in their ability to succeed in species selection and establishment.  The Landcare group provided a lot of support in species selection, and, as the demand for shrubs grew, the nurseries responded by increasing their availability.

Nearly all revegetation in West Hume has used local species, and as far as possible these were grown from locally sourced seed.  The diversity of shrub species used increased over the years as knowledge and availability of the local flora improved.

Roadside survey. Local knowledge was greatly increased following the roadside survey carried out by 38 landholder volunteers.  They surveyed 460 km of road, recording floristics, conservation value and causes of degradation.  A total of 111 native species were recorded, including 28 shrubs, but very few road sections had greater than 50% shrub cover.  Many of the shrubs. grasses and forbs recorded are considered rare in the landcare area.  Knowledge of the whereabouts of these small remnants has allowed seed collection and propagation of some of them in seed production areas on local properties and at the Wirraminna Environmental Centre at Burrumbuttock.  The need for this local source of seed has been emphasised by the observation that in the case of a few acacia species, local forms are different from those growing in neighbouring areas.

Landcare survey. Landholder views about the importance of vegetation was shown in a landcare survey carried out in 1999. A majority of the 60% of respondents considered that dieback of trees and the lack of shrubs, understorey and wildflowers was of concern and there was a clear concern expressed about the decline of native birds in the area.

When the “Taking Charge of Recharge” project was funded in 2001, the response of landholders was enthusiastic.  The group members were eager to take advantage of the high level of incentives available in this project to increase the scale of planting beyond that generally undertaken previously.  While the prime purpose of the funding was for recharge management, members were keen to establish local species in ecologically appropriate sites.  Ecological and botanical skills within the group were able to support the species choices.

This confidence in the value and feasibility of large revegetation projects has been continued in subsequent years when the Murray CMA has offered good incentives for large area plantings.

Contact:  Judy Frankenberg, +61 2 6026 5326, Email: judy@frankenberg.com.au

Fig 1. School student volunteers planting in block AA on ‘Warrangee’ in 1995.

Fig 1. School student volunteers planting in block AA on ‘Warrangee’ in 1995.

Fig 2. Resulting tree and shrub habitats created from 1995 planting on block AA, 2013.

Fig 2. Resulting tree and shrub habitats created from 1995 planting on block AA, 2013.

Fig 3. ‘Corridors of green’ project, 2013, planted in 1994, “Warrangee” .

Fig 3. ‘Corridors of green’ project, 2013, planted in 1994, “Warrangee” .

Holbrook Landcare “Rebirding the Holbrook Landscape” – assessing performance and learning in action

Chris Cumming and  Kylie Durant

Key words: tree dieback, lerps, restoring the agricultural landscape, community involvement, Holbrook Landcare Network

Holbrook producers established Holbrook Landcare Network in 1988.  It was one of the first Landcare groups in Australia, covering initially 171,000 ha of productive agricultural land in the upper reaches of the Murray Darling Basin. The organisation has directly managed grants of more than $6M across more than 85 projects to address NRM and agricultural issues including salinity and erosion control, soil and pasture management the protection of wildlife habitat.

Of the habitat projects, one of the most successful has been the “Rebirding Project”. A recognition of the importance of birds in the landscape occurred in 1994, when there was widespread concern in Holbrook over eucalypt tree dieback and the potential loss of paddock trees in the landscape. Holbrook Landcare commissioned a survey that identified 41% of the trees in the district were showing signs of dieback, and initiated (with support from our own extension staff and Greening Australia) education programs to inform landholders about the causes of dieback, including the link between cycles of lerp and other insect attack exacerbated by the loss of insectivorous birds.

In 1999 the group was successful in gaining funding for the “Rebirding the Holbrook Landscape to mitigate dieback” revegetation program through the Australian Governments Natural Heritage Trust (NHT), with the aim of drawing birds back onto farms and reducing eucalypt tree dieback.

Actions undertaken. Bird surveys were undertaken at 94 study sites in remnant vegetation on hills, flats and along creek lines. Education components succeeded in engaging the community and increased community knowledge and awareness of habitat issues in Holbrook.  The research information was used to recommend specific guidelines for the revegetation component, including ideal patch size (min 6ha), distance to remnant (1km), position in the landscape and habitat values.

The Rebirding on-ground projects (1999 – 2002) achieved 2150ha of remnant and revegetation work and put 475,000 plants back in the landscape across 118 properties – estimated at 80% of the Holbrook landholders.

Outcomes achieved. Measuring success of the program was very important to the community. A partnership with CSIRO Sustainable Ecosystems gave rise to a research project measuring bird use of plantings and remnant vegetation on local farms in 2004 to 2006.  This found that a range of bird species rapidly colonised planted areas and showed evidence of breeding activity, a positive message about the early signs of success of the Rebirding project. Tree health monitoring is ongoing by the community. Current ANU research is showing the positive benefit of the revegetation work in the landscape at the site, farm and landscape scale. The science is therefore indicating that yes, “rebirding” of the Holbrook landscape is underway, and HLN will continue to look to science to help us with the longer term outcomes for birds and tree health, and provide the feedback to us to adaptively manage our programs for the best outcomes.

The lessons and recommendations that come from the research are being applied directly to inform the design of subsequent programs such as the current major biodiversity project being managed by Holbrook Landcare – the “Slopes to Summit Bushlinks Project”.

Contacts: Chris Cumming (Executive Officer) and Kylie Durant,  Holbrook Landcare Network, PO Box 181 Holbrook NSW, Australia.  2644 Tel: +61 2 6036 3121, Email: kyliedurant@holbrooklandcare.org.au.

Paddock tree health field day, Holbrook, 2011.

Paddock tree health field day, Holbrook, 2011.

Before planting habitat blocks at Woomargama station, Holbrook.

Before planting habitat blocks at Woomargama station, Holbrook.

Stands of trees and shrubs established at Woomargama station, Holbrook.

Stands of trees and shrubs established at Woomargama station, Holbrook.