Category Archives: Bush regeneration

Eastern Suburbs Banksia Scrub: is fire the key to restoration? – UPDATE to EMR SUMMARY

Geoff Lambert, and Judy Lambert

[Update to EMR summary  – Geoff Lambert and Judy Lambert (2015) Progress with restoration and management of Eastern Suburbs Banksia Scrub on North Head, Sydney.  Ecological Management & Restoration, 16:2, 95-199. https://onlinelibrary.wiley.com/doi/10.1111/emr.12160]

Key Words. Banksia Scrub, North Head, Critically Endangered Ecological Community, Diversity.

Fig 1. Images of the same location over time, taken from “walk-through” photographic surveys (top to bottom) pre-fire, immediate post-fire and 5-years post-fire. (Photos Geoff Lambert)

Introduction. In the original feature, we reported on a number of projects related to the fire ecology of Eastern Suburbs Banksia Scrub (ESBS), also known as Coastal Sand Mantle Heath (S_HL03), located in conserved areas on North Head, Sydney Australia. Following a Hazard Reduction burn in September 2012, we examined changes in species numbers and diversity and compared these measures with control areas which had been thinned. We fenced one-third of the survey quadrats to test the effects of rabbit herbivory. There had been no fire in this area since 1951.

Twelve months after treatment, burned ESBS had more native plants, greater plant cover, more native species, greater species diversity and fewer weeds than did thinned ESBS (Fig 1). Areas that had been fenced after fire had “superior” attributes to unfenced areas. The results suggested that fire could be used to rejuvenate this heath and that this method produced superior results to thinning, but with a different species mix. Results of either method would be inferior were attempts not made to control predation by rabbits (See 2015 report).

Further works undertaken. In 2015 and 2017 we repeated the surveys, including photographic surveys on the same quadrats. Further Hazard Reduction burns were conducted, which provided an opportunity to repeat the studies reported in the 2015 feature. The study design of the burns was broadly similar to the earlier study, but rabbits were excluded by fencing four large “exclosures” over half the burn site. The pre-fire botanical survey was carried out in 2014, with logistical difficulties delaying the burn until late May 2018. Drought and other factors saw a post-fire survey delayed until October 2019. Photographic surveys of the quadrats have been completed.

Seven cm-resolution, six-weekly, aerial photography of North Head is regularly flown by Nearmap© (Fig 2). We use this photography to monitor the whole of the headland and, in particular, the various burn areas. In order to extrapolate from our quadrat-based sampling (usually 1% of a burn area), the University of Sydney flew 5mm-resolution UAV-based surveys on our behalf, on one of the 2012 burn areas and on the 2018 burn area in November 2017 (Fig 3) .

Apart from the fire studies, the general program of vegetation propagation and management has been continued by the Sydney Harbour Federation Trust and the North Head Sanctuary Foundation. The Australian Wildlife Conservancy has also undertaken a “whole of headland”, quadrat-based vegetation survey as the first stage of its “Ecological Health” rolling program for its sites.

Fig 2. Nearmap© site images (top to bottom) pre-fire, immediate post-fire and 7-years post-fire. (Photos Nearmap)

Further results. The original results suggested that fire could be used advantageously to rejuvenate ESBS and produced superior results to thinning. While subsequent photographic monitoring shows distinct vegetation change (Figs 1 and 2), on-ground monitoring showed that by five years after the fire we could no longer say this with any optimism. In summary:

  • In the immediate fire aftermath, there was vigorous growth of many species
  • Over the ensuing 5 years, plants began to compete for space, with many dropping out
  • Species diversity was high following the fire but then dropped below pre-fire levels
  • Some plants (e.g. Lepidosperma and Persoonia spp.) came to dominate via vegetative spread
  • The reed, Chordifex dimorphus has almost disappeared
  • Tea-trees (Leptospermum spp.) are gradually making a comeback
  • Between 2015 and 2017, ESBS species numbers were outpaced by non-ESBS species, but held their own in terms of ground cover.

The total disappearance of Chordifex (formerly an abundant species on North Head and prominent in the landscape) from fully-burned quadrats was not something that we could have predicted. This species is not in the Fire Response database, although some Restio spp. are known to be killed by fire. This contributes greatly to the visual changes in the landscape. The great proliferation of Lance Leaf Geebung (Persoonia lanceolata) has also changed the landscape amenity (Fig 1, bottom).

To summarise, the 2012 burn has not yet restored ESBS, but has produced a species mix which may or may not recover to a more typical ESBS assemblage with ongoing management over time. Given that the area had not been burned for 60 years, it may be decades before complete restoration.

Our further studies on the use of clearing and thinning on North Head as an alternative to fire (“Asset Protection Zone Programme”), indicates that thinning and planting can produce a vegetation community acceptable for asset protection fire management and potentially nearly as rich as unmanaged post-fire communities (Fig 4). It is necessary to actively manage these sites by removing fire-prone species every two years. In addition, a trial has been started to test whether total trimming of all except protected species to nearly ground level in an APZ, is an option for longer-term management.

Fig 3. “Thinning Experiment” fenced quadrat #3 in July 2019. The quadrat was created in 2013 by removing Coastal Teatree (Leptospermum laevigatum) and Tree Broom Heath (Monotoca elliptica). The experimental design is a test of raking and seeding, with each treatment in the longer rows. All non-endangered species plants were trimmed to 0.25 metres height in mid-2017. (Photo Geoff Lambert)

Lessons learned and future directions. It is too early to say whether we can maintain and/or restore North Head’s ESBS with a single fire. Further fires may be required. A similar conclusion has been drawn by the Centennial Parklands Trust, with its small-scale fire experiments on the York Road site. We need new and better spot- and broad-scale surveys and further burns in other areas on North Head over a longer period. The spring 2019 survey, just completed, offers an opportunity to better assess the notion that fire is beneficial and necessary.

It will be necessary to monitor the effects of future fires on ESBS diversity closely and for much longer than five years. More active management of the post-fire vegetation may be needed, as we have previously discussed in the feature, and as happens at Golf Club sites (also see video) .

The 2012 burn was relatively “cool”. There is some evidence that “hot” burns (such as have been carried out by NSW Fire and Rescue at some Eastern Suburbs golf courses) may produce improved restoration of ESBS. The 2018 burn on North Head was planned as a “hot” burn. This was not completely achieved, but we may be able to compare “hot” and “cool” burn patches within it.

Fig 4. A 2017 UAV image of quadrat 23 five years after the 2012 burn. The image has been rotated to show the quadrat aligned on the UTM grid. The red square shows the rabbit-proof fences; the black square shows the survey quadrat and the blue squares show the four 1×1 metre vegetation plots. The resolution is approximately 5 mm. (Photo University of Sydney Centre for Field Robotics)

Stakeholders. Sydney Harbour Federation Trust, North Head Sanctuary Foundation. Australian Wildlife Conservancy, NSW National Parks and Wildlife Service, Fire & Rescue NSW.

Funding Bodies. Foundation for National Parks & Wildlife [Grant No. 11.47], Sydney Harbour Federation Trust, Australian Wildlife Conservancy.

Contact Information. Dr G.A.Lambert, Secretary, North Head Sanctuary Foundation, (P.O.Box 896, BALGOWLAH 2093, Tel: +61 02 9949 3521, +61 0437 854 025, Email: G.Lambert@iinet.net.au. Web: https://www.northheadsanctuaryfoundation.org.au/

Ku-ring-gai Flying-fox Reserve Habitat Restoration Project at Gordon, 2000 – 2019 UPDATE of EMR feature

Nancy Pallin

[Update to EMR feature –  Pallin, Nancy (2001) Ku-ring-gai Flying-fox Reserve Habitat restoration project, 15 years on.  Ecological Management & Restoration 1:1, 10-20.  https://onlinelibrary.wiley.com/doi/10.1111/emr.12229]

Key words:         bush regeneration, community engagement, wallaby browsing, heat events, climate change

Figure 1. Habitat restoration areas at Ku-ring-gai Flying-fox Reserve within the urban area of Gordon, showing areas treated during the various phases of the project. Post-2000 works included follow up in all zones, the new acquisition area, the pile burn site, the ecological hot burn site and sites where vines have been targeted. (Map provided by Ku-ring-gai Council.)

Introduction. The aim of this habitat restoration project remains to provide self-perpetuating indigenous roosting habitat for Grey-headed Flying-fox (Pteropus poliocephalus) located at Ku-ring-gai Flying-fox Reserve in Gordon, NSW Australia (Fig 1).  The secondary aim was to retain the diversity of fauna and flora within the Flying-fox Reserve managed by Ku-ring-gai Council. Prior to works, weed vines and the activity of flying-foxes in the trees had damaged the canopy trees while dense weed beneath prevented germination and growth of replacement trees.  Without intervention the forest was unable to recover.  Natural regeneration was assisted by works carried out by Bushcare volunteers and Council’s contract bush regeneration team.  The work involved weed removal, pile burns and planting of additional canopy trees including Sydney Bluegum (Eucalyptus saligna), which was expected to cope better with the increased nutrients brought in by flying-foxes.

Figure 2. The changing extent of the Grey-headed Flying-fox camp from the start of the project, including updates since 2000. (Data provided by KBCS and Ku-ring-gai Council)

Significant changes have occurred for flying-foxes and in the Reserve in the last 20 years.

In 2001 Grey-headed Flying-fox was added to the threatened species lists, of both NSW and Commonwealth legislation, in the Vulnerable category.  Monthly monitoring of the number of flying-foxes occupying the Reserve  has continued monthly since 1994 and, along with mapping of the extent of the camp, is recorded on Ku-ring-gai Council’s Geographical Information System. Quarterly population estimates contribute to the National Monitoring Program to estimate the population of Grey-headed Flying-fox.  In terms of results of the monitoring, the trend in the fly-out counts at Gordon shows a slight decline.  Since the extreme weather event in 2010, more camps have formed in the Sydney basin in response to declining food resources.

In 2007, prompted by Ku-ring-gai Bat Conservation Society (KBCS), the size of the Reserve was increased by 4.3 ha by NSW Government acquisition and transfer to Council of privately owned bushland. The Voluntary Conservation Agreement that had previously established over the whole reserve in 1998 was then extended to cover the new area.   These conservation measures have avoided new development projecting into the valley.

From 2009 Grey-headed Flying-fox again shifted their camp northwards into a narrow gully between houses (Fig 2).  This led to human-wildlife conflict over noise and smell especially during the mating season. Council responded by updating the Reserve Management Plan to increase focus on the needs of adjoining residents.  Council removed and trimmed some trees which were very close to houses. In 2018 the NSW Government, through Local Governments, provided grants for home retrofitting such as double glazing, to help residents live more comfortably near flying-fox camps.

Heat stress has caused flying-fox deaths in the Reserve on five days since 2002. Deaths (358) recorded in 2013, almost all were juveniles of that year.  KBCS installed a weather station (Davis Instruments Vantage Pro Plus, connected through a Davis Vantage Connect 3G system) and data loggers to provide continuous recording of temperature and humidity within the camp and along Stoney Creek.  The station updates every 15 minutes and gives accurate information on conditions actually being experienced in the camp by the flying-foxes. The data is publicly available http://sydneybats.org.au/ku-ring-gai-flying-fox-reserve/weather-in-the-reserve/Following advice on the location and area of flying-fox roosting habitat and refuge areas on days of extremely high temperatures (Fig 3.) by specialist biologist Dr Peggy Eby, Council adopted the Ku-ring-gai Flying-fox Reserve 10 Year Management and Roosting Habitat Plan in 2018.  Restoration efforts are now focused on improving habitat along the lower valley slopes to encourage flying-foxes to move away from residential property and to increase their resilience to heat events which are predicted to increase with climate change.

Figure 3. Map showing the general distribution of flying-foxes during heat events, as well as the location of exclosures. (Map provided by Ku-ring-gai Council)

Further works undertaken.  By 2000 native ground covers and shrubs were replacing the weeds that had been removed by the regeneration teams and Bushcare volunteers.  However, from 2004, browsing by the Swamp Wallaby (Wallabia bicolor) was preventing growth of young trees and shrubs.  Bushcare volunteers, supported by KBCS and Council responded by building tree cages made from plastic-mesh and wooden stakes. Reinforcing-steel rods replaced wooden stakes in 2008.   From 2011, the Bushcare volunteers experimented with building wallaby exclosures, to allow patches of shrubs and groundcovers to recover between trees (Figs 3 and 4).  Nineteen wallaby exclosures have been built. These range in size from 7m2 to 225m2 with a total area of 846m2.   Wire fencing panels (Mallee Mesh Sapling Guard 1200 x 1500mm) replaced plastic mesh in 2018.  Silt fence is used on the lower 0.5m to prevent reptiles being trapped and horizontally to deter Brush Turkey (‎Alectura lathami) from digging under the fence.

The wallaby exclosures have also provided an opportunity to improve moisture retention at ground level to help protect the Grey-headed Flying-fox during heat events.  While weed is controlled in the exclosures south of Stoney Creek, those north of the creek retain Trad and privets, consistent with the 10 Year Management and Roosting Habitat Plan.

Madeira Vine (Anredera cordifolia) remained a threat to canopy trees along Stoney Creek for some years after 2000, despite early treatments.  The contract bush regen team employed sInce 2010 targeted 21 Madiera Vine incursions.

A very hot ecological burn was undertaken in 2017 by Council in order to stimulate germination of soil stored seed and regenerate the Plant Community Type (PCT) – Smooth-barked Apple-Turpentine-Blackbutt tall open forest on enriched sandstone slopes and gullies of the Sydney region (PCT 1841).  This area was subsequently fenced. The contract bush regeneration team was also employed for this work to maintain and monitor the regeneration in the eco-burn area (720 hours per year for both the fire and Madiera Vine combined).

Figure 4. Exclusion fence construction method. Pictured are Bushcare volunteers, Jill Green and Pierre Vignal. (Photo N Pallin).

Figure 5. Natural regeneration in 2018 in (unburnt) exclosure S-6 (including germination of Turpentines). (Photo N. Pallin)

Further results to date. The original canopy trees in Phase 1 and Phase 2 (1987 -1997) areas have recovered and canopy gaps are now mostly closed. Circumference at breast height measurements were taken for seven planted Sydney Blue gum trees.  These ranged from 710 to 1410mm with estimated canopy spread from 2 to 6m.  While original Turpentine (Syncarpia glomulifera) had circumferences from 1070 and 2350mm with canopy spread estimated between 5and 8m, those planted or naturally germinated now have circumference measurements between 420 and 980mm with canopy spread estimated from 1.5 to 3m.  A Red Ash (Alphitonia excelsa) which naturally germinated after initial clearing of weeds now has a circumference of 1250mm with a canopy spread of 5m.  Also three Pigeonberry Ash (Elaeocarpus kirtonii) have circumference from 265 to 405mm with small canopies of 1 to 2m as they are under the canopies of large, old Turpentines.  As predicted by Robin Buchanan in 1985 few Blackbutt (Eucalyptus pilularis) juveniles survived while the original large old trees have recovered and the Sydney Bluegum trees have thrived.

In the Phase 3 (1998 – 2000) area south of Stoney Creek the planted Sydney Blue Gum now have circumferences measuring between 368 and 743 (n7) with canopy spread between 2 and 6 m.  in this area the original large trees have girths between 1125 and 1770mm (n7) whereas trees which either germinated naturally or were planted now range from 130 to 678mm (n12).  These measurement samples show that it takes many decades for trees to reach their full size and be able to support a flying-fox camp.

Wallaby exclosures constructed since 2013 south of Stoney Creek contain both planted and regenerated species.  Eight tree species, 11 midstorey species, 27 understorey species and eight vines have naturally regenerated.  Turpentines grew slowly, reaching 1.5m in 4 years.  Blackbutts thrived initially but have since died. In exclosures north of the creek,  weeds including Large-leaved Privet,  Ligustrum lucidum,  Small-leaved privet,  L. sinense,  Lantana, Lantana camara,  and Trad, Tradescantia fluminensis) have been allow to persist and develop to maximise ground moisture levels for flying-foxes during heat events. Outside the exclosures, as wallabies have grazed and browsed natives, the forest has gradually lost its lower structural layers, a difference very evident in Fig 6.

Figure 6. Visible difference in density and height of ground cover north and south of Stoney creek. (Photo P. Vignal)

Coachwood (Ceratopetalum apetalum) were densely planted in a 3 x 15m exclosure under the canopies of mature Coachwood next to Stoney Creek in 2015. In 4 years they have reached 1.5m.  In this moist site native groundcovers are developing a dense, moist ground cover.

Madiera Vine, the highest-threat weed, is now largely confined to degraded edges of the reserve, where strategic consolidation is being implemented with a view to total eradication.

In the hot burn area, which was both fenced and weeded, recruitment has been outstanding. One 20 x 20m quadrat recorded 58 native species regenerating where previously 16 main weed species and only 6 native species were present above ground. A total of 20 saplings and 43 seedlings of canopy species including Eucalyptus spp., Turpentine and Coachwood were recorded in this quadrat where the treatment involved weed removal, burning and fencing  (S. Brown, Ku-ring-gai Council, July 2019, unpublished data).  Unfortunately, however, the timing and location of the burn did not take into account its impact on the flying-fox camp and there was some damage to existing canopy trees. It will be many years before the canopy trees, which are regenerating, will be strong enough to support flying-foxes.

Monitoring from the weather station and data loggers has shown that close to Stoney Creek on a hot day it is typically 2-3° C cooler, and 5-10% higher in humidity, than in the current camp area (pers. comm. Tim Pearson). During heat events the flying-foxes move to this cooler and moister zone, increasing their chances of survival.

Fauna observed other than flying-foxes includes a pair of Wedge-tail Eagle ( Aquila audax plus their juvenile, a nesting Grey Goshawk (Accipiter novaehollandiae) and a Pacific Baza (Aviceda subcristata).  Powerful Owl (Ninox strenua) individuals continue to use the valley. The presence of raptors and owls indicate that the ecosystem processes appear to be functional. Despite the decline of the shrub layer outside fenced areas, the same range of small bird species (as seen prior to 2000) are still seen including migrants such as Rufous Fantail ( Rhipidura rufifrons) which prefers dense, shady vegetation. The first sighting of a Noisy Pitta (Pitta versicolor) was in 2014.  Long-nosed Bandicoot (Perameles nasuta) individuals appear and disappear, while Swamp Wallaby remains plentiful.

Lessons learned and future directions. Climate change is an increasing threat to Pteropus species. On the advice of Dr Eby, Flying-fox Consultant, Council, KBCS and Bushcare Volunteers agreed to retain all vegetation including weeds such as Large-leaved Privet and Small-leaved Privet, patches of the shrub Ochna (Ochna serrulata) and Trad as a moist ground cover in the camp area and areas used by the flying-foxes during heat events.

Building cheap, lightweight fencing can be effective against wallaby impacts, provided it is regularly inspected and repaired after damage caused by falling branches. This style of fencing has the additional advantage of being removable and reusable.  It has been proposed that, to provide understory vegetation to fuel future burns in parts of the reserve away from the flying-fox camp, further such temporary fencing could be installed.

Ku-ring-gai Council has commenced a  program to install permanent monitoring points to annually record changes in the vegetation, consistent with the state-based  Biodiversity Assessment Method.

Stakeholders and Funding bodies. Members of KBCS make donations, volunteer for monthly flyout counts, Bushcare and present educational events with live flying-foxes. KBCS hosts the website www.sydneybats.org.au. Ku-ring-gai Council which is responsible for the Reserve has been active in improving management to benefit both residents and flying-foxes.  Ku-ring-gai Environmental Levy Grants to KBCS have contributed substantially to purchase of fencing materials and the weather station. http://www.kmc.nsw.gov.au/About_Ku-ring-gai/Land_and_surrounds/Local_wildlife/Native_species_profiles/Grey-headed_flying-fox

Thank you to Jacob Sife and Chelsea Hankin at Ku-ring-gai Council for preparing the maps and to volunteer Pierre Vignal for assistance with tree measurements, downloading data loggers and a photo.  Researcher,  Tim Pearson installed the weather station.

Contact information. Nancy Pallin, Management Committee member, Ku-ring-gai Bat Conservation Society Inc.  PO Box 607, Gordon 2072  Tel 61 418748109. Email:  pallinnancy@gmail.com

Developments in Big Scrub Rainforest Restoration: UPDATE of EMR feature

Tony Parkes, Mark Dunphy, Georgina Jones and Shannon Greenfields

[Update of EMR feature article: Parkes, Tony, Mike Delaney, Mark Dunphy, Ralph Woodford, Hank Bower, Sue Bower, Darren Bailey, Rosemary Joseph, John Nagle, Tim Roberts, Stephanie Lymburner, Jen Ford and Tein McDonald (2012) Big Scrub: A cleared landscape in transition back to forest? Ecological Management & Restoration 12:3, 212-223. https://doi.org/10.1111/emr.12008]

Key words: Lowland Subtropical Rainforest, ecological restoration, seed production, landholder action, corridors

Figure 1a. Rainforest regenerators undertake camphor injection, leaving bare trees standing creating light and an opportunity for seed in the soil to naturally regenerate. (Photo © Envite Environment)

Figure 1b Aerial photo showing camphor conversion by injection
(Photo © Big Scrub Regeneration Pty. Ltd.)

Introduction. The Big Scrub, on the NSW north coast, was once the largest tract of Lowland Subtropical Rainforest (LSR) in Australia. It was reduced to less than 1% of its original extent by he end of hte 19th century after clearing for agriculture. Big Scrub Landcare (BSL) is a non-profit organisation dedicated to improving the long-term ecological functionality of what remains of this critically endangered ecosystem –  lowland subtropical rainforest.  Our 2012 EMR feature reported on remnant restoration and revegetation works overseen by BSL to 2012. At that time, 68 remnants were identified as significantly affected from the impacts of environmental degradation including weed invasion and cattle access. These remnants had been undergoing treatments, with 20 substantially recovered and on a ‘maintenance’ regime.  Approximately 900,000 trees had been planted to establish 250 ha of young diverse well-structured rainforest.  A comparatively small area of forest dominated by the highly invasive exotic, Camphor Laurel (Cinnamomum camphora) (Camphor), which  has colonised much of the Big Scrub landscape had been converted to early phase LSR by skilled removal of a range of weeds and facilitating natural regeneration. 

Progress since 2012. Substantial progress in restoring critically endangered lowland subtropical rainforest in the Big Scrub has been achieved over the past seven years in the following areas.

  • Assisted regeneration of remnants has continued and become more focused
  • Re-establishment of LSR through plantings has expanded
  • Camphor conversion has developed in scale and techniques
  • Greater security of funding has been achieved
  • Community engagement has greatly improved and expanded
  • Genome science is being applied to produce seed with optimal genetic diversity for rainforest restoration.

Assisted regeneration of remnants. This work continues to be the major focus of on-ground restoration work. About 2000 regenerator days (9 years Full Time Equivalent) of work has been undertaken in 45 remnants. BSL’s remnant restoration program has become more strategic, with more focus on Very High Conservation Value (VHCV) remnants, particularly those in the NSW National Parks Estate, including the VHCV sites in Nightcap National Park (NP) including Big Scrub Flora Reserve, Minyon Falls and Boomerang Falls; Andrew Johnston’s Scrub NR; Snow’s Gully Nature Reserve (NR); Boatharbour NR; Victoria Park NR and Davis Scrub NR, plus the Booyong Flora Reserve. Rehabilitation work at these sites is prioritised in the major new four-year Conservation Co-funding project funded jointly by BSL and the NSW government’s Saving our Species program. Big Scrub Foundation (BSF) funding has enabled BSL to continue maintenance work in remnants that have reached or are approaching the maintenance stage.

Monitoring outcomes has become more rigorous and has demonstrated ongoing improvements in vegetation structure, with decreasing levels of weed invasion and improvements in native species cover.

BSL’s partner Envite Environment, with some assistance from BSL, is creating an important linkage between Nightcap NP and Goonengerry NP by the restoration of rainforest through the progressive removal of weeds that had dominated the 80 ha Wompoo/Wanganui corridor between these two NPs.

 Re-establishment of rainforest by planting. The area of LSR is being re-established by planting on cleared land has also continued to expand.   In the last 7 years  more than 0.5 million rainforest trees have been planted in the Big Scrub region, contributing to the restoration of another 175 ha of LSR, expanding total area of re-established rainforest by another 13%. While landscape-scale landholder driven work is inevitably opportunistic rather than strategic, the establishment of new patches of LSR enhance valuable stepping-stone corridors across the Big Scrub. Since 2012 the number of regenerators working fulltime in the Big Scrub region has increased by approximately 50%.  Another trend that has strengthened in the last 7 years is that larger plantings are now being carried out by well-resourced landowners. This is accounting for about 40% of the annual plantings. Offsets for residential development account for another 40% of trees planted. The remaining 20% is made up by small landowners, cabinet timber plantations, large-scale landscaping, and other planting of Big Scrub species. This is a significant change from the more dominant grant-based small landowner/Landcare group plantings prior to 2012.

 Camphor conversion. Larger areas of Camphor forest are being converted to rainforest, with project areas increasing substantially from less than a hectare to ten and twenty hectares. BSL estimates that more than 150 ha of Camphor forest are currently under conversion. Some landowners underake camphor injection which leaves bare trees standing, creating light and an opportunity for existing native seedlings and seed in the soil (or seed dropped by perching birds) to naturally regenerate (Fig 1). Others are choosing the more expensive option of physically removing the Camphor trees and carefully leaving the rainforest regrowth (Fig 2).  Improved techniques and landholder capacity building continue to progress and camphor conversion is now a significant component of rainforest restoration.

BSL alone is facilitating the conversion of almost 40 ha of Camphor forest to LSR funded by two 3-year grants from the NSW Environmental Trust, together with contributions from the 19 landholders involved in these projects. The ecological outcomes being achieved are significant and less costly than revegetation via plantings.

Figure 2a. Camphor forest under conversion using heavy machinery leaving rainforest regrowth intact (Photo © Big Scrub Landcare)

Figure 2b. Aerial photo showing camphor conversion by removal
(Photo © Big Scrub Landcare)

Greater security of funding. Australian Government funding for biodiversity conservation is at a very low level. Competition for existing NSW state government funding is increasing. BSL therefore has continued to  develop new strategies for fund raising to ensure continuity of its long-term program for the ecological restoration of critically endangered LSR in the Big Scrub and elsewhere. Ongoing funding of at least $150,000 annually is needed to ensure the great progress made  over the past 20 years in rehabilitating remnants is  maintained and expanded to new areas of large remnants. These funds finance weed control and monitoring; weeds will always be a part of the landscape and an ongoing threat to our rainforest remnants.

Establishment of the Big Scrub Foundation in 2016 was a major development in BSL’s fund raising strategy. The Foundation received a donation of AUD $1M to establish a permanent endowment fund that is professionally invested to generate annual income that helps finance BSL’s remnant care program and its other activities. Generous donors are also enabling the Foundation to help finance the Science Saving Rainforest Program.

Figure 3a. Australian gardening celebrity Costa Gregoriou at a Big Scrub community tree planting (part of the 17th annual Big Scrub Rainforest Day) in 2015 (Photo © Big Scrub Landcare)

Figure 3b. Founder of the Australian Greens political party Bob Brown and Dr. Tony Parkes at the 18th annual Big Scrub Rainforest Day in 2016. (Photo © Big Scrub Landcare)

Community engagement. The  Big Scrub Rainforest Day continues to be BSL’s  major annual community engagement event, with the total number of attendees estimated to have exceeded 12,000 over the past 7 years; the 2016 day alone attracted more than 4000 people (Fig 3). Every second year the event is held at Rocky Creek Dam.  A new multi-event format involving many other organisations has been introduced on alternate years.

BSL’s Rainforest Restoration Manual has been updated in the recently published third edition and continues to inform and educate landowners, planners and practitioners.

BSL in partnership with Rous County Council produced a highly-commended book on the social and ecological values of the Big Scrub that has sold over 1000 copies. BSL’s website has had a major upgrade: its Facebook page is updated weekly; its e-newsletter is published every two months. BSL’s greatly improved use of social media is helping to raise its profile and contribute to generating donations from the community, local businesses and philanthropic organisations to fund its growing community education and engagement work and other activities.

Science saving rainforests program. BSL, the Royal Botanic Gardens Sydney, the BSF and their partners have commenced an internationally innovative program to apply the latest DNA sequencing and genome science to establish plantations to produce seed of key species with optimal genetic diversity for the ecological restoration of critically endangered lowland subtropical rainforest. This program will for the first time address the threat posed by fragmentation and isolation resulting from the extreme clearing of Australia’s LSR, which is estimated to have resulted in the destruction of 94% of this richly biodiverse Gondwana-descended rainforest.

Many  key  LSR species are trapped in small populations in  isolated remnants  that  lack the genetic diversity needed to adapt and survive in the long term, particularly faced with climate change Necessary  genetic diversity is also lacking in many key species in the 500 ha of planted and regrowth rainforest. The first stage of the program, already underway, involves collecting leaf samples from approximately 200 individual old growth trees in 35 remnant populations across the ranges of 19 key structural species of the ‘original’ forest. DNA will be extracted from the leaf samples of each species and sequenced. The  latest genome science will be applied to select the 20 individual trees of each species that will be cloned to provide planting stock with optimal genetic diversity for the establishment of a living seed bank in the form of a plantation that will produce seed  for use in restoration plantings. As the individual trees in the restoration plantings reproduce, seed with appropriate genetic diversity and fitness will be distributed across the landscape. The project focuses on key structural species and thus helping the survival of Australia’s critically endangered Lowland Subtropical Rainforest in the long term.

Lessons learned and current and future directions. A key lesson learned some five years ago was that BSL had grown to the point where volunteers could no longer manage the organisation effectively. BSL took a major step forward in 2015 by engaging a part-time Manager, contributing to BSL’s continuing success by expanding the scope, scale and effectiveness of its community engagement activities and improving its day to day management.

The principal lesson learned from BSL’s on-ground restoration program is to focus on rehabilitation of remnants and not to take on large planting projects, but rather support numerous partnered community tree planting events. Large grant-funded multi-site tree planting projects are too difficult to manage and to ensure landholders carry out the necessary maintenance in the medium to long term.

Acknowledgements.  BSL acknowledges our institutional Partners and receipt of funding from the NSW government’s Saving our Species program, NSW Environmental Trust and Big Scrub Foundation.

Contact:  Shannon Greenfields, Manager, Big Scrub Landcare (PO Box 106,  Bangalow NSW 2479 Australia; . Tel: +61 422 204 294; Email: info@bigscrubrainforest.org.au Web: www.bigscrubrainforest.org.au)

Lord Howe Island biodiversity restoration and protection programs, NSW, Australia

Hank Bower

Key words: Pest species management, weed control, community engagement.

Figure 1. Weeding teams apply search effort across near 80% of island terrain, their effort monitored through record of GPS track logs across designated weed management blocks. Target weeds on LHI are mostly bird dispersed requiring landscape scale for sustainable and long-term protection from weeds. The remaining 20% of island is subject to surveillance and with investigation of new technical approaches in weed detection using drones.

Introduction: Lord Howe Island (LHI) is located in the Tasman Sea 760 km northeast of Sydney and 570 km east of Port Macquarie. In 1982 the island was inscribed on the World Heritage (WH) List under the United Nations’ World Heritage Convention in recognition of its superlative natural phenomena and its rich terrestrial and marine biodiversity as an outstanding example of an island ecosystem developed from submarine volcanic activity.

The island supports at least 80% cover of native vegetation, broadly described as Oceanic Rainforest with Oceanic Cloud Forest on the mountain summits.  LHI vegetation comprises 239 native vascular plant species with 47% being endemic. Forest ecosystems on LHI are largely intact, but at threat from invasive species and climate change. About 75% of the terrestrial part of the WH property is recognised as a Permanent Park Preserve (PPP) managed on behalf of the New South Wales government by the Lord Howe Island Board on the basis of a holistic conservation and restoration plan (Lord Howe Island Biodiversity Management Plan LHI BMP 2007).

Since settlement of the island in 1834, introduced and invasive plant and animal species have been affecting the Lord Howe Island environment, causing declines in biodiversity and ecosystem health. There have been 11 known extinctions and severe declines in numbers of fauna species including the flightless Lord Howe Woodhen (Hypotaenidia sylvestris), once regarded as one of the rarest birds in the world.  The Lord Howe Island Phasmid (Dryococelus australis), the world’s largest stick insect was feared extinct until the rediscovery of live specimens on Balls Pyramid in 2001. Some 29 species of introduced vertebrates and about 271 species of introduced plant species have naturalised on the island. At least 68 species are the focus for eradication (Fig 1), with 10 main invasive species having colonised extensive areas of the settlement and the PPP, posing a serious threat to island habitats. One of the most serious weeds, Ground Asparagus (Asparagus aethiopicus), for example, was so prolific in the forest understory it completely overwhelmed native vegetation and bird breeding grounds. Weeds are prioritised for eradication following a Weed Risk Assessment and are typically species that are at low density, are localised and/or are limited to gardens, and species with known weed characteristics (e.g. wind or bird dispersed seeds) that have yet to express their weed potential. Identifying species for early intervention is important to prevent their establishment and expansion, particularly post rodent eradication. For example, the removal of 25 individual Cats Claw Creeper in 2006 (which have not been detected since) supports the case for proactive weed management.

The islands limited size and isolation provides great opportunities to achieve complete removal and eradication of key invasive species.  Therefore particular strategies identified in the LHI BMP to effect ecosystem recovery include the management and eradication of invasive weeds, rodents, tramp ants and protection from plant diseases and pathogens.  All projects are delivered at an island wide scale, which incorporates a permanent population of 350 residents and a tourist bed limit of 400.

Works undertaken   Progressive programs to eradicate feral animals commenced in 1979 with the eradication of pig Sus scrofa, cat Felus catus in 1982, goat Capra hircus in 1999 and African Big-headed Ant Pheidole megacephala in 2018. Threatened fauna recovery programs include the captive breeding of Lord Howe Woodhen following the eradication of cats, establishing a captive breeding and management program for the Lord Howe Island Phasmid and the planning and gaining of approvals to implement the eradication program for Black Rat Rattus rattus, House Mouse Mus musculus and introduced Masked Owl Tyto novehollandiae commencing in 2019.

The island wide strategic Weed Eradication Program commenced in 2004, building on earlier years of ad-hoc control effort.  Over 2.4 million weeds have been removed through more than 170,000 hours of grid search method.  Now, near mid-way point of a 30-year LHI Weed Eradication Project (LHIWEP), teams have reduced weed infestations (of all life stages) by 80%.  Ten year program results of the LHIWEP are summarised (LHIB 2016 – Breaking Bad) http://www.cabi.org/isc/abstract/20163360302, which clearly shows the significance of multi-invasive species management to achieve ecosystem recovery.

With the spread of Myrtle Rust Austropuccinia psidii to the Australian mainland in 2010 the LHI Board has been on high alert.  With five endemic plants at risk to this pathogen the LHIB provided training and information to the community on the threats to the island and food plants. The LHIB prepared a Rapid Response Plan and a Rapid Response Kit (fungicides and Personal Protective Equipment). In October 2016 Myrtle Rust was detected on exotic Myrtaceae species, from three leases and subsequently treated in November 2016. This also resulted in the eradication of three highly susceptible exotic myrtaceous plant species from the island.

The root fungus Phytophthora cinnamomi is known from one lease and has been quarantined and treated with granular fungicide quarterly. Periodic monitoring has shown the infestation to be reducing with the eventual aim of eradication. Boot sanitization stations located at all track heads applies effort to prevent introduction of root rot fungus and other soil borne pathogens from users of the walking track system in the PPP.

The LHI Board has carried out a range of local community engagement and visitor education programs to raise awareness of the risks and threats to the island environment and of the LHIB environmental restoration and protection programs. These include a LHI User Guide for visitors to the island and a citizen science program with the LHI Museum, establishing the LHI Conservation Volunteer program to help improve awareness of the importance of LHI conservation programs to both tourists and tourism business. Since 2005, over 150 volunteers supported by the LHIB and external grants have been engaged through the weed eradication project. Increasingly, LHI residents are volunteering to gain experience and to improve employment opportunities in restoring their island. Another long-term partner, Friends of Lord Howe Island, provide invaluable volunteer assistance with their Weeding Ecotours, contributing more than 24,000 hours of weeding building valuable networks.

Biosecurity awareness is critical to protect the investment in conservation programs and the environment to future threats. The LHI Board provide information regarding biosecurity risks to the community, stevedores and restaurateurs. The LHIB now hold two biosecurity detection dogs and handlers on island (Figure 3) whom work with Qantas and freight flights and shipping staff to ensure they are aware of biosecurity risks and plan for appropriate responses.

Results to date.  Achievements include the successful eradication of over 10 weed species, cat, pig, goat, African Big-headed Ant and Myrtle Rust. A further 20+ weeds are considered on the verge of being able to be declared eradicated in coming years with an 80% reduction in weed density island wide and a 90% reduction in the presence of mature weeds. Weed Risk Assessments will be applied to determine the impact or new and emerging weeds and appropriate management actions.

As a result of the eradication of feral pigs and cats and an on-island captive breeding program, the endangered Lord Howe Island Woodhen has recovered to an average of 250 birds. The other eradications, along with the significant reduction in dense and widespread weed invasions, has aided the recovery and protection of numerous endemic and threatened species and their habitats. The program’s significant outcomes have been recognised through the IUCN Conservation Outlook which in 2017 scored the Lord Howe Island Group’s outlook as good, primarily due to the success of projects that have, are being and are planned to be implemented to restore and protect the islands unique World Heritage values. In late 2018 the program received awards for excellence from the Society for Ecological Restoration Australasia (SERA), Green Globe and Banksia Foundations, acknowledging the sustained effort from the Board and Island community in working to restore and protect the island.

Lessons learned and future directions:  The main keys to success has been obtaining expert scientific and management input and actively working with, educating and involving the community (lease holders and local businesses) to help achieve the solution to mitigate and remove invasive species.

The Rodent Eradication Program scheduled for winter 2019 will result in less browsing pressure on both native and invasive plants species, as well as the removal of two domestic pests. Prior to the program the LHIB has targeted the control of introduced plants, currently in low numbers, that may spread after rodent eradication. Monitoring programs are in place to measure ecosystem response with a particular focus on the Endangered Ecological Community Gnarled Mossy Cloud Forest on the summit of Mt Gower. Should the project be successful, consideration can be given to the reintroduction of captive bred individuals of the Lord Howe Island Phasmid as well as other species confined to offshore islands (e.g. Lord Howe Wood Feeding Roach Panesthia lata) or ecological equivalent species on other islands (Norfolk Boobook Owl Ninox novaeseelandiae, Norfolk Parakeet Cyanoramphus cookii, Norfolk Island Grey Fantail Rhipidura albiscapa and Island Warbler Gerygone igata).

Stakeholders and Funding bodies:  The Program is managed by the Lord Howe Island Board and the NSW Department of Environment and Heritage, in collaboration with the local LHI community.

The LHI Board acknowledge the generations of islander stewardship, teams on ground, researchers, the funding and support agencies, all who made it happen. These include but are not limited to NSW Environmental Trust, Caring for Our Country, National Landcare Program, North Coast Local Land Services, Zoos Victoria, Taronga Zoo, Australian Museum, CSIRO, Friends of LHI, the Norman Wettenhall Foundation and Churchill Trust.

Contact: Hank Bower, Manager Environment/World Heritage, Lord Howe Island Board, PO Box 5, LORD HOWE ISLAND, NSW 2898, Tel: +61 2 65632066 (ext 23), Fax: 02 65632127, hank.bower@lhib.nsw.gov.au

Video conference presentation: https://www.aabr.org.au/portfolio-items/protecting-paradise-restoring-the-flora-and-fauna-of-world-heritage-listed-lord-howe-island-hank-bower-and-sue-bower-lhi-board-aabr-forum-2016/

Establishment of an assisted natural regeneration model for Big Scrub sub-tropical rainforest: The Woodford Method

The results of long-term restoration at Rocky Creek Dam, have informed the development of an assisted natural regeneration model for sub-tropical rainforest known as The Woodford Method (named after the pioneering restoration work of Ralph Woodford). This method is now commonly applied across the Big Scrub region, particularly on high resilience sites and is more fully explained in Woodford (2000).

Figure 1. Remove Lantana thickets.

Figure 1. Remove Lantana thickets.

1. Winter (July-August) – refer Figure 1. In a typical area of secondary regrowth dominated by weeds such as Camphor Laurel (Cinnamomum camphora), Privet (Ligustrum sinense) and Lantana (Lantana camara), Lantana is the weed that should be killed first. Winter is the best time to do this as it is dry and it won’t reshoot when on the ground. In extensive areas, this can be done effectively by flattening thickets of Lantana with a tractor, then slashing it repeatedly to create a deep mulch, and pulling the Lantana stumps out to disturb the soil. Removing the Lantana thickets also allows access to tree weeds.

Figure 2. Kill Privet and Camphor Laurel.

Figure 2. Kill Privet and Camphor Laurel.

2. Spring (September-October) – refer Figure 2. Tree weeds such as Camphor and Privet have their biggest growth spurt, so this is a good time to give them a shot of herbicide to kill them. (Leaving the Camphor in place rather than cutting them down means that they act as ‘perch trees’ for birds and bats to land on and spread seeds through their droppings). As the Lantana, Camphor and Privet die, their leaves and branches fall to the ground and form a rich mulch on the forest floor. Light is also able to reach the forest floor, where previously it had only reached the canopy.

Spring storms come and wet the mulch, and fungal mycelium (the feeding filaments of fungi) move through the mulch and break it down, fertilising and leaving bare patches of soil where the mulch layer has totally receded.

Figure 3. Remove annual weeds.

Figure 3. Remove annual weeds.

3. Late spring / early summer (November-January) – refer Figure 3. Where you have bare soil, and there is moisture, light and an appropriate temperature, you will get seed germination. The first things to come up are annual weeds such as ‘Farmers Friends’ or ‘Cobblers Pegs’ (Bidens pilosa); ‘Blue Billy Goat Weed’ (Ageratum houstonianum); and ‘Crofton’ or ‘Mistweed’ (Ageratina spp). Annual weeds are always first to appear. They will germinate on the smell of a storm and a slight increase in temperature. Camphor and privet seedlings often come up at the same time.

When the weeds grow, they form a canopy just like the forest but at a height of one metre. In this way, weeds stop light from reaching the forest floor, inhibiting the growth of rainforest seedlings.

Therefore, it is important to remove these annual weeds and not let them go to seed. Depending on time available they are either pulled or sprayed. The experience at this site has been that the seedbank is strong enough to lose some rainforest seedlings in this initial spraying. If using herbicide, two sprays during this season generally removes all the weeds and their seeds.

Figure 4. Weed around rainforest seedlings.

Figure 4. Weed around rainforest seedlings.

4. Late summer / early autumn (February-March) – refer Figure 4.The seeds of rainforest species tend to germinate after the highest summer temperatures (sometimes up to 38 and 40 degrees) have passed. By late February and early March, daytime temperatures don’t generally go over 30 degrees, but the soil temperature and moisture is at its maximum. These conditions can produce a massive germination of rainforest seeds and those seedlings grow up very rapidly. Hand weeding is usually needed around these rainforest ‘pioneers’.

Figure 5. Enjoy the growing rainforest.

Figure 5. Enjoy the growing rainforest.

5. Early winter (May-June) – refer Figure 5. On a good site, with the best seasonal conditions, many of these rainforest seedlings will have grown to saplings above head height and can create a closed canopy within the same year. This means that less light reaches the forest floor, which reduces the amount of weed regrowth in this area – but there is still enough light for later successional rainforest seedlings to germinate, building the rainforest diversity over time.

Note: The process may be slightly different depending on the type of ‘before restoration’ landscape. Refer to Woodford (2000) for more information.

Contact: Anthony Acret,  Catchment Assets Manager, Rous Water, NSW Australia. Tel+62 2 6623 3800; Email: anthony.acret@rouswater.nsw.gov.au

Restoration at Numinbah Conservation Area, City of the Gold Coast, Queensland

Key Words: assisted regeneration, restoration planning, conservation

Introduction: Numinbah Conservation Area, located in the hinterland of the Gold Coast in south-east Queensland, is one of many natural areas managed by City of Gold Coast’s Natural Areas Management Unit (NAMU). The 598 ha property contains 12 Regional Ecosystems (REs) ranging from sub-tropical and dry rainforest to dry and wet sclerophyll types; and include riparian zones, steep areas, gullies and rocky outcrops. Its conservation value is heightened by the fact that it connects to other reserves including the World Heritage areas of Springbrook.

Condition ranges from large degraded areas (i.e. pasture) to native vegetation that contains both regrowth and remnant areas. All areas were impacted by weeds due to previous disturbance from logging and subsequent cattle grazing. More than 35 weed species impact the site at varying levels with the most notable species across the site being Lantana (Lantana camara). Edges are impacted by exotic vines such as Glycine (Neonotonia wightii), the understorey by many herbaceous weeds such as Mistflower (Ageratina riparia) and rainforest zones by persistent weeds such as Coral Berry (Rivina humilis) and Passion Vines (Passiflora spp.) to name a few. Approximately 60 hectares of open area are dominated by pasture grasses and other weeds.

The aim of the project is to restore, to the extent possible, the structure, function, dynamics and integrity of the pre-existing vegetation and the sustaining habitat that is provided. Our goals are to:

  • Improve the health of vegetation and habitat types across the site
  • Improve connectivity for flora and fauna
  • Reduce fuel levels in fire prone ecosystems and the risk of hot fires sweeping through the site and wider landscape
  • Increase the resilience of the site
  • Improve water quality
  • Increase the health, populations and distribution of threatened species – flora and fauna
  • Reduce the need for weed control maintenance over time i.e. to a level of minimal maintenance
  • Provide nature based recreational opportunities and environmental education along this section of the Gold Coast Hinterland Great Walk

Planning. An ecological restoration plan was developed after detailed site assessments and the site was divided into precincts, zones and sub-zones to assist directing works. Information in the plan included species lists, weed control information, maps and detail on how to restore each area and progressively link zones. A detailed fire management plan was also developed for the site that took into account wildfire mitigation, restoration zones, the location of threatened species, site objectives, REs including their recommended fire regimes, and the capacity of areas to regenerate.

Works to date. Works over the last 9 years have covered more than 190 ha. The main approach to restoration has been via assisted regeneration consisting mainly of large scale weed control and the fencing of areas to reduce the impact of cattle. Further works have involved planting a section of creek to assist stability and connectivity across a section of the site; and the propagation and translocation of four threatened flora species (details not disclosed for security reasons).

Where low intensity fuel reduction burns were conducted in dry sclerophyll vegetation, timely follow up weed control was applied to ensure re-shooting Lantana, Molasses Grass (Melinis minutiflora) and other weeds did not fill gaps and to support the colonisation and growth of native vegetation. In remnant and regrowth vegetation, systematic weed control using a range of techniques has been applied. E.g. large areas of Lantana were controlled using three techniques: cut, scrape and paint where it was in close proximity to native plants; over-spraying after isolating infestations; and, spot-spraying when it germinated or was re-shooting. Weed species were continually suppressed to ensure native species germinated and grew to a point where most gaps have been filled with native vegetation. As each area developed and maintenance reduced, efforts were put into continually expanding the work fronts.

A propagation and translocation project was also implemented in partnership with Seqwater. More than 1150 individuals (four species) have been propagated, planted into their particular niche and have been monitored and reported on annually. This will continue until all species are considered to be self-sustaining i.e. flowering, fruiting and reproducing.

(a)NCA8n_20080502

(b)NCA8n_20080827

(c) NCA8n_20090716

(d)NCA8n_20100625

(e)NCA8n_20110630

(f)NCA8n_20151130

Figure 1, (a-f) represents an annual sequence of recovery after control of Lantana and subsequent weed at one photopoint from 2008 to 2011, with the last photo taken in 2015. The results reflect accurate and timely weed control to support the recovery of native vegetation. (Photos: City of Gold Coast)

Results to date. As of July 2015, weeds have been significantly reduced across the 190 ha treated area to a point where maintenance is being applied, with some areas requiring little to no maintenance. In a number of areas this reduction of weed has also significantly reduced fuel levels.

Increased abundance and diversity of native vegetation has occurred across a range of ecosystem and habitat types within the reserve. Open areas once dominated by dense Lantana have taken approx. 3 years to naturally regenerate with a range of pioneer, early secondary and later stage rainforest species (Figs 1-3). Many of those areas now include continuing recovery of later stage species and contain a large diversity of seedlings, groundcovers and ferns. More diverse communities have recovered with a large range of species (depending on the ecosystem / ecotone) and support a diversity of fauna species. Works in four of the larger precincts have now joined up and weed control works are continuing to expand all regenerating areas.

More than 7000 plants installed along the open riparian stretch are establishing with native species regenerating amongst the planting. After approx. 7 years the average height of the planted canopy is approx. 5-7m tall.

Ongoing works: All current work zones are being continuously extended ensuring progress made is maintained. The open area (e.g. paddock) is being reduced over time as vegetation is encouraged to expand (i.e. by continuing to control weeds to past the drip lines of all native vegetation). Fences that currently contain cattle (i.e. to assist managing open areas for access, fire management and to ensure funds are spent in more resilient areas) are being moved to continue to reduce the size of highly degraded areas. Fire management, large scale weed control and the monitoring and evaluation of threatened species, together with fauna surveys, is continuing.

Stakeholders and funding bodies: Natural Areas Management Unit (NAMU), City of Gold Coast and Seqwater. Contact Information Paul Cockbain, Team Leader Restorations +61 7 5581 1510

 

Forested wetland regeneration project, The Gap Road Woodburn, NSW

Julie-Anne Coward

Contract bush regeneration works involving fire and weed management commenced in 2011 in 2.5 ha of endangered ecological coastal floodplain communities at the Cowards’ property on the Gap Road, Woodburn in northern NSW (Fig 1). An area of 7.19 ha of the 10ha property had been recently covenanted for conservation by new owners and 2 small grants were gained to convert the previous grazing property back to forested wetland. Remnant vegetation existed on the property and regrowth was already occurring, although extensive areas were dominated by exotic pasture grasses, particularly >1m high swathes of Setaria (Setaria sphacelata).

Works commenced with spraying of the weed with herbicide and regular follow up spot spraying of weed regrowth. However, because the dead Setaria thatch was taking a long time to break down (and high weed regeneration was likely) a burn was carried out to hasten the recovery responses to fit within the 3 year funding cycle. The works were monitored before and at 6 monthly intervals using 6 (9m2) quadrats in each of hot burn, cool burn and unburnt areas (Fig 1).

Fig 1. Works zones at the Gap Road wetland

Figure 1. Works zones at the Gap Road wetland – mapped in April 2013 where the quadrats were laid out. and data recorded prior to and at 6-monthly intervals after treatment.

Works undertaken. A 2-3m wide firebreak was cut around the burn area and a burn was conducted in dry conditions on Oct 19th 2012 (Fig 2) by the landholders, assisted by Minyumai Green Team and with the local fire brigade on standby. The fire burnt approximately 0.5 ha of the Setaria-dominated area, most of which had been previously sprayed (Fig 2).

Results. A more complete (and presumably hotter) burn was achieved in the sprayed areas (Figs 3 and 4). Setaria and Ragweed germinated prolifically, with a few natives and the site was virtually blanket sprayed with glylphosate. By the second follow up natives had started to regenerate so spot-spraying was used thereafter, taking care to protect the natives. Within 5 months quadrats in the sites that burned hotter achieved over 50% native cover, while the unburnt area achieved only half (25%) that cover. Both areas ultimately achieved similar recovery of natives, but markedly higher spot spraying inputs over longer time frames were needed in the unburnt areas compared to the hotter burn areas.

Over the three year contract, unexpectedly high and prolific regeneration occurred of 35 species of native forbs, sedges and grasses (germinating from buried seed banks) and 7 species trees and shrubs (largely from seed rain) (Fig 5). However, weed germination was also prolific, particularly in unburnt areas, and required at least monthly levels of continual suppression.

fig 2. The burn itself (Oct 17, 2015)

Figure 2. The burn itself (Oct 17, 2015)

Figure 3. Sprayed Setaria prior to the burn.

Figure 3. Sprayed Setaria prior to the burn.

Figure 3. Prolific native groundcover and tree regeneration 2 years after the burn and as a result of consistent spot spraying.

Figure 3. Prolific native groundcover and tree regeneration 2 years after the burn and as a result of consistent spot spraying.

Lessons learned. The proximity of remnant vegetation (within 100m) and intact soil profile was important to the native recovery. At least monthly weed control is essential and can achieve results on its own. However, the project involved substantial volunteer time as well as contract labour – and when labour was insufficient new weed populations formed in the disturbed areas that then required more intensive treatment to overcome. Comparing the demand for weed control in burnt and unburnt areas showed that the feasibility of weed control is very much reduced without the use of fire to flush out weed at the outset.

Acknowledgements: The project is dedicated to the memory of Murray Coward who helped initiate the project. Minyumai Green Team (Daniel Gomes, Justin Gomes, Chris Graves and Andrew Johnston) have kept the project on track over the years, with assistance from Tein McDonald. Thanks is due to the EnviTE team, particularly Virginia Seymour, for their work at the site in the first 18 months. The project is covenanted with the Nature Conservation Trust of NSW (NCT) and received some initial funding from NCT. It subsequently gained a $15K Private Land Conservation Grant (funded by Foundation for National Parks and Wildlife and managed through the NCT) and has now gained a second, similar grant to continue and expand the works.

Contact: Julie-Anne Coward, Gap Road Woodburn. Email: mjcets1@bigpond.com

Re-introducing burning to Themeda Headland Grassland EEC, Narooma, NSW.

Tom Dexter, Jackie Miles, Deb Lenson

Key Words: Fire management, threatened ecosystem, Kangaroo Grass, weed management, Themeda

Introduction: In 2012, Eurobodalla Shire Council commenced a project to preserve local stands of declining Themeda Headland Grassland on Council managed land on three small headlands north of Narooma, NSW. Themeda Grassland on Seacliffs and Coastal Headlands is an Endangered Ecological Community (EEC) that grows on higher fertility soils and is listed under the NSW Threatened Species Conservation Act 1995.

Burning was trialed at two of the three sites to test whether fire could improve the environmental integrity of these sites. This trial has potential implications for the much larger stands of this EEC in various conservation reserves scattered along the NSW coastline as there are many which are not currently actively managed.

The three sites were slashed annually until 2010. While the dominant grass, Kangaroo Grass (Themeda triandra) was still present on all sites, the sites exhibited some decline in Kangaroo Grass cover and vigour, with weed present on all three sites (Fig 1). Slashing had kept the headlands free from shrubs however windrows of slashed grass suppressed Kangaroo Grass and appeared to encourage weed invasion. One of the sites, which was left unburnt for logistic reasons, was initially in worse condition than the other two due to the presence of an old vehicle track and more extensive weed cover particularly from Kikuyu (Pennisetum clandestinum).

The intensity of a burn is likely to vary on a seasonal basis and is dependent on the build-up of dead thatch and the prevailing conditions on the day. There is basis to believe that the traditional aboriginal burning would have taken place in Autumn and would have been a relatively cool burn. The optimum time to burn when considering the constraints of weed invasion is early spring.

Fig 1. Mowing damage at Duesburys Beach headland

Fig 1. Lines of bare ground indicate the location of windrows of dead grass from a history of mowing at Duesburys Beach headland

Works undertaken: Two successive burns were conducted in early spring on 2 of the 3 headlands, in August 2013 and August 2014 (Fig 2). The burn in 2013 was hotter than the burn in 2014 due to a higher build up of Kangaroo Grass thatch prior to the burn.

Follow-up weed control was implemented after the burns as the fire created gaps between the grasses and allowed targeted chemical control minimizing off target damage to Kangaroo Grass and other native species.

Data were collected on three occasions using ten 1 x 1 m quadrats, established along a 50 m transect spaced at 5 m intervals (one of these for each headland). The initial baseline data were recorded in Nov 2012, prior to the spring burns, and in each successive summer (2013/14 and 2014/15) following the burns.

Fig 2. Dalmeny Headlands burn 2015

Fig 2. Typical burn on the headlands

Results to date: The burnt areas (Figs 3 and 4) showed a significant decrease of annual exotic grasses; especially of Quaking Grass (Briza maxima) and Rats Tail Fescue (Vulpia spp.). The burnt areas also showed vigorous Kangaroo Grass growth and moderate seed production of that species. Two native species -Dwarf Milkwort (Polygala japonica) and Matgrass (Hemarthria uncinata Fig 5) not recorded prior to treatment were found after treatment in the quadrats. The most abundant native forbs, Swamp Weed (Selliera radicans) and Indian Pennywort (Centella asiatica) have persisted on the quadrats but not increased (Fig 6). Some exotic forbs – e.g. Yellow Catsear (Hypochaeris radicata) and Scarlet Pimpernel (Anagallis arvensis) have taken advantage of the removal of grass biomass and have also increased, further future analysis will determine whether this increase will impact on the native forbs. Perhaps the most important finding is the Coast Banksia (Banksia integrifolia) seedlings were killed by the fire allowing the sites to remain grassland.

The unburnt headland continues to deteriorate, with ongoing evidence of continued senescense of Kangaroo Grass, no Kangaroo Grass seed production, and exotic plants continuing to replace Kangaroo Grass in parts of the site. Kikuyu is the main exotic species on this site and is responsible for continued suppression of the native components of the grassland. There is also evidence of shrub invasion beginning to occur. It is anticipated that this site will be burnt in spring 2015.

Fig 2. Duesburys Point just after fire, Sept 2013

Fig 3. Duesburys Point just after burning, Sept 2013

Fig 3. Same site 11 months later, Aug 2014

Fig 4. Same site 11 months later, Aug 2014

What we learned: Kangaroo Grass remains vigorous throughout the burnt sites. The results to date show annual burning to be generally beneficial to the herbaceous components and associated grasses of this EEC. There was a higher success of exotic annual grass control in the first year which is most likely attributed to a hotter fire and perhaps timing. The first year also had accumulated multiple years of thatch which may have assisted fire intensity. Supplementary chemical control was effective, particularly when the fire created gaps between the grasses, allowing for better targeted chemical control.

Future directions: So far the results have shown that an August fire followed by the targeted chemical control of exotic grasses has considerable positive influence on the overall environmental integrity of this ecosystem. The annual burning allows the EEC to remain a grassland by killing off Coast Banksia and Coastal Acacia seedlings. It invigorates Kangaroo Grass growth and reduces the biomass of exotic perennial grasses at least in the short term. This again creates an opportunity in the aforementioned targeted chemical control. The herbaceous composition of the headland also remains intact and future analysis will determine whether burning has either a neutral or positive effect on growth. Kikuyu, Paspalum (Paspalum dilitatum) and annual exotic weeds continue to be the main problem. Increased post-burn selective herbicide application or hand weeding and planting of Kangaroo Grass tubestock may help to restore the grassland more rapidly than use of fire with limited weed control alone. Ongoing funding is being sought to continue the works over coming years and achieve further positive future outcomes.

Acknowledgements: The works were undertaken by Eurobodalla Shire Council with funding from the NSW Environmental Trust. Fire assistance from the NSW Rural Fire Service and cultural advice provided by Elders of the Walbunja people.

Contact: Tom Dexter; Environment and Sustainability Project Officer; Eurobodalla Shire Council (PO Box 99 Vulcan St Moruya 2537, Australia. Email: tom.dexter@eurocoast.nsw.gov.au).

Fig 5. Hemarthria uncinata was more evident after fire. (Duesburys Beach headland.)

Fig 5. Hemarthria uncinata was only evident after fire. (Duesburys Beach headland.)

Fig 5. More forbs among the grass after fire at Duesburys Point – e.g. Sellaria radicans

Fig 6. The forb Sellaria radicans persisted  among the grass after fire.

 

Wompoo Gorge Lowland Subtropical Rainforest Restoration Project, Coopers Creek, New South Wales

Key words : Connectivity, Lowland Subtropical Rainforest, Threatened Species

Introduction. Much of the state- and nationally listed Lowland Subtropical Rainforest at Wompoo Gorge, located on Coopers Creek near Rosebank, was partially cleared for pasture early last century. Parts of the cleared forest regenerated naturally with the removal of agricultural activities from the site during the 1940s-50s, but Lantana (Lantana camara) established in large gaps (Fig 1) and prevented any further rainforest regeneration. This weed domination reduced the function of an important habitat linkage between Nightcap and Goonengerry National Parks. Twenty-seven threatened species (10 threatened flora species and 17 vulnerable animal species) have been recorded on the site, which has been identified as a key climate change and wildlife corridor.

In 2009 a program of ecological restoration commenced, guided by the recommendations of the Wompoo Gorge (South) Ecological Restoration Plan (updated in 2013). The aim of the restoration works was to control Lantana and other weeds, restoring the integrity of the rainforest and helping to supporting the region’s exceptional biodiversity.

A monitoring program was established on site prior to commencement of works. This included eight transects and photopoints. Structural and floristic information has been collated and photos taken prior to the commencement of works, and subsequently over the course of restoration work. Data have been entered into then MERV (Monitoring and Evaluation of the Restoration of Vegetation) database and used to produce reports.

Figure 1. (map) Lantana cover prior to restoration. By 2014 very little lantana remained with regenerating rainforest taking the place of weeds.

Figure 1. (map) Lantana cover prior to restoration. By 2014 very little lantana remained with regenerating rainforest taking the place of weeds.

Works undertaken: Lantana has been controlled by a range of methods (Figs 2-4) including: mechanically with a tractor; spraying with a splatter gun; over-spraying dense, less accessible areas; hand weeding with brush hooks and loppers; and, cut/scrape and paint of scattered Lantana among remnant vegetation. Other less dominant weeds have been controlled to facilitate replacement of Lantana with regenerating rainforest. Follow-up work includes flattening down dead Lantana, spot spraying and hand weeding. No planting has been undertaken but fruit from native plants on site has been collected and spread throughout regeneration areas.

Figure 2. September 2009: Prior to lantana control

Figure 2. September 2009: Prior to lantana control

Figure 3.  17 September 2009: Tractor crushes down lantana

Figure 3. 17 September 2009: Tractor crushes down lantana

Figure 4. 21 October 2009: Second tractor run slashing lantana

Figure 4. 21 October 2009: Second tractor run slashing lantana

Results: Lantana has been virtually eliminated from extensive areas and vigorous regeneration of a high diversity of species has occurred (Figs 5-6). Common regenerating species include: Poison Peach (Trema aspera), Red Cedar (Toona ciliata), Giant Stinging Tree (Dendrocnide excelsa), Tamarind (Diploglottis australis), Sandpaper Figs (Ficus coronata) White Cedar (Melia azedarach) Bangalow Palm (Archontophoenix cunninghamiana), Brown Kurrajong (Commersonia bartramia), Pencil Cedar (Polyscias murrayi), Celerywood (P. elegans), Quandong (Elaeocarpus grandis) , Black Bean (Castanosperma australis), Sally Wattle (Acacia melanoxylon). Groundcovers included Soft Bracken Fern (Calochlaena dubia), Cunjevoi (Alocasia brisbanensis) Juncus (Juncus sp.), Cyperus (Cyperus spp.) and Basket Grass (Oplismenus aemulus). A range of later stage rainforest species have also germinated including Hairy Walnut (Endiandra pubens), Maiden’s Blush (Sloanea australis) and White Bolly Gum (Neolitsea dealbata).

Figure 5. ‘’Oct 2010: Resilient native regeneration in tractor cleared area

Figure 5. Oct 2010: Resilient native regeneration in tractor cleared area

Figure 6. May 2014: Natives have replaced lantana throughout cleared area

Figure 6. May 2014: Natives have replaced Lantana throughout cleared area

What we have learned. Wompoo Gorge has proven to be a highly resilient site, located as it is between two major sources of propagules. The site’s unique location, resilience and beauty has made it an ideal site to educate and inspire the community to restore rainforest Field days held on site have assisted in raising regional awareness of the value of the Lowland Rainforest EEC, the habitat it provides and of the degrading impacts of weeds. Various weed control techniques have also been discussed and demonstrated. Involving Green Army participants alongside professional regenerators has helped Green Army participants gaining valuable knowledge, skills and training in ecological restoration.

In 2014 NSW National Parks and Wildlife Service acquired the property realising the goal of former property owner Dailan Pugh to protect the property in perpetuity for the benefit of conserving native species and for future generations.

Acknowledgements: The project has received funding from the NSW Environmental Trust’s Restoration and Rehabilitation program. Additional funding has been invested through the former Northern Rivers Catchment Management Authority, the Great Eastern Ranges Initiative and a Raymond Borland Landcare grant. In 2015 Green Army teams have commenced working on site, alongside professional bush regenerators, undertaking additional and complimentary restoration works.

Contact: Paul O’Connor, Technical Manager, EnviTE Environment, 56 Carrington Street (P.O.Box 1124) Lismore  2480 Australia.

Tel: +61 2 6627 2841 Mob: + 61 427 014 692. Email: paulo@envite.org.au

 

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).