Category Archives: NCC 2015 Fire and restoration conference

Fire as a tool in maintaining diversity and influencing vegetation structure – Grassy Groundcover Restoration Project

Posted on 14 December 2015 by | Comments Off on Fire as a tool in maintaining diversity and influencing vegetation structure – Grassy Groundcover Restoration Project

Paul Gibson-Roy

Greening Australia’s Grassy Groundcover Restoration Project commenced in 2004 to investigate the feasibility of restoration of grasslands and grassy woodlands (primarily by direct seeding) in the agricultural footprint of Australia. To date the project has achieved the reconstruction of grassy understories in grassland or grassy woodland on near to 100 sites in ex-agricultural land (predominantly across Victoria, but increasingly in southern to central New South Wales and mid-lands Tasmania). Post establishment we use fire in our sites to reduce biomass, particularly to inhibit grass growth which over time become the dominant life form, just like trees can in other communities. Opening the grass canopy allows for the small forbs and sub-dominant grasses to regenerate. Burning in particular can help create these canopy gaps and in a cost-effective way.

Fig 1. Snake Gully CFA burn at Chepstowe.

Fig 1. Snake Gully CFA burn at Chepstowe.

Fig 2. Restored herb-rich grassland on roadside near Wickliffe.

Fig 2. Restored herb-rich grassland on roadside near Wickliffe.

Fig 3. Differential management of Kangaroo Grass at Rokewood Cemetery.

Fig 3. Differential management of Kangaroo Grass at Rokewood Cemetery.

Operational challenges can and often do arise considering sites are located within urban or agricultural footprints where protection of life and property is paramount. This at times prompts us to consider alternative methods of biomass removal such as through grazing (sometimes used as a method for annual weed control) and mowing when burning is deemed inappropriate. These alternative or complimentary biomass reduction methods can also have additional benefits. For example, mowing and producing bales of cut straw, if cut in early spring or autumn, can be used for fodder. This is also the case with grazing. Alternatively, if sites are cut and baled in late spring or summer when grasses contain ripe seed, the hay can be moved and spread at other locations to create a grassland elsewhere.

While the project has carried out various combinations of these approaches at our restored grasslands in recent years, the following list includes a few examples of their use.

  1. Burning at Chepstowe (located to the west of Ballarat, Victoria) to reduce grass biomass and allow forbs to establish and persist. The burn is being conducted by Snake Gully CFA members (Figure 1).
  2. The nationally threatened species – Hoary Sunray (Leucochrysum albicans tricolor) and Button Wrinklewort (Rutidosis leptorrynchoides) were introduced by direct seeding along with many other ground layer species onto a roadside near Wickliffe, Victoria. Following establishment the grassland has been managed with fire by the Wickliffe CFA so that grasses do not dominate and the rare species can recruit and spread. (Figure 2.)
  3. Kangaroo Grass (Themeda triandra) growth has been the focus of differing management techniques within the Rokewood cemetery reserve Victoria (under the Cemetery Trusts grassland management plan). This remnant grassland contains the largest Victorian population of the nationally threatened Button Wrinklewort. To avoid the Kangaroo grass dominating the herb rich areas, it is maintained by fire, whereas in the approaches to the burial area it is kept mown low for function and protection of the memorial infrastructure. (Figure 3).
  4. Similar opening of a restored grassy canopy is achieved at Chatsworth in south western Victoria where a grassland currently dominated by Wallaby Grass (Rytidosperma setaceum) was mown and baled (Figures 4 and 5). This material was used to as fodder by the landholder.
  5. A late autumn burning of herb-rich restored grassland at Hamilton, Victoria, undertaken by the Buckley Swamp CFA (Figure 6).
  6. The aforementioned site at Hamilton taken in the following spring. It shows visitors touring the restoration where Common Everlasting (Chrysocephalum apiculatum) and many other sub-dominant forb species are in full bloom (Figure 7).
  7. Diverse restored grassland located adjacent to a wheat crop at Point Henry, near Geelong, Victoria. This site 16 ha site has been maintained over time by combinations of burning and cutting and baling (Figure 8).
Fig 4. Wallaby grass dominated grassland at Chatsworth pre-baling.

Fig 4. Wallaby grass dominated grassland at Chatsworth pre-baling.

Fig 5. Wallaby grass dominated grassland at Chatsworth post-baling.

Fig 5. Wallaby grass dominated grassland at Chatsworth post-baling.

Fig 6. Buckley Swamp CFA conducting a late autumn burn of restored herb-rich grassland near Hamilton.

Fig 6. Buckley Swamp CFA conducting a late autumn burn of restored herb-rich grassland near Hamilton.

Deciding which method or combination of biomass removal techniques to use, and at what time can be complex and there is no textbook. Good management is about constantly assessing the landscape and prevailing conditions to identify prompts for action. It is also about having the right networks and technical capacity available when required. As a general rule we find that when a site has greater than 70% vegetation cover of the ground surface and dry material is being held above 150 mm, there is enough combustible material to carry a flame. This condition also indicates that that the gaps in the vegetation are starting to close up.

Contact: (Dr) Paul Gibson-Roy. Lead Scientist, Greening Australia.Tel: +61 437591097. Email: PGibson-Roy@greeningaustralia.org.au

[This project summary is a precis of a talk presented to the Nature Conservation Council of NSW’s 10th Biennial Bushfire Conference, ‘Fire and Restoration: Working with Fire for Healthy Lands’ 26-27 May 2015. For full paper see: http://www.nature.org.au/healthy-ecosystems/bushfire-program/conferences/%5D

Fig 7. Spring and wild flowers are in bloom at Hamilton.


Fig 7. Spring and wild flowers are in bloom at Hamilton.

Fig 8. Species and functionally diverse restored grassland adjoining a wheat crop near Geelong.

Fig 8. Species and functionally diverse restored grassland adjoining a wheat crop near Geelong.

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Posted in agricultural lands, Fauna & habitat, Fire Ecology & Management, Grassland/grassy understorey, Integrating ecosystems & industries, NCC 2015 Fire and restoration conference, Restoration & management theory, Techniques & methodology, Threatened species & communities, Victoria, Weed issues & solutions

Managing fire for nature conservation in subtropical woodlands

Posted on 2 December 2015 by | Comments Off on Managing fire for nature conservation in subtropical woodlands

Emma Burgess, Murray Haseler and Martine Maron

Introduction. A study investigating the response of bird assemblages to mosaic burning is being conducted on 60,000 hectares private nature reserve in the Brigalow Belt bioregion of Queensland (Fig 1). The Brigalow Belt has recently experienced high rates of native vegetation clearing, motivating Bush Heritage Australia (BHA) to purchase and protect the property in 2001. The subsequent removal of cattle and horses from Carnarvon Station Reserve has increased grass and herb biomass. The seasonal surge in productivity the property now experiences however, increases the potential for more intense, frequent and extensive fires in hot, dry conditions. The risk of such wildfires needs to be managed, and a common approach to such management is prescribed burning. But how to ensure nature conservation objectives are still met?

Fig 1. Locality map of Carnarvon Station Reserve

Fig 1. Locality map of Carnarvon Station Reserve

In fire ecology, there is a common assumption that if we introduce a range of burn conditions to produce a mosaic of patches with different fire histories (pyrodiversity) – then the resulting diversity in fire histories and the greater representation of successional stages of vegetation is expected to accommodate more species in a given area (Fig. 2). Reducing the spatial scale at which fire history turns over- the “breaking up” of country- is also known as the patch mosaic burning approach.

Fig 2. Diagram of mosaic burning approach

Fig 2. Diagram of mosaic burning approach

Whilst we assume that pyrodiversity will give us increased habitat diversity, and therefore greater animal diversity, there is uncertainty as to the scale (alpha, beta or gamma diversity) at which pyrodiversity might influence biodiversity (Fig. 3). Alpha diversity is the total number of different species within a site or habitat; beta diversity is the difference in species composition between sites or habitats; and gamma diversity is the number of different species across all sites or habitats in the area of interest. At what spatial scale do we see the benefit for birds of mosaic burning (Fig. 3)?

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Methods: We examine the relative influence of the diversity of fire histories, spatial configuration of these fire histories, spatial extent of particular fire histories and other measures of environmental heterogeneity on:

  1. Aggregated measures of bird species richness at both the landscape- (100 ha) and local-scale (1 ha); and
  2. Response of different bird foraging guilds to mosaic burning, at both the landscape- and local-scale.

 So what did we find? The diversity of fire regimes in the 100-ha landscape did not correlate with average site (alpha) or landscape- (gamma) diversity of birds. Rather, the total area of longer-unburnt vegetation was important for increasing bird richness at the landscape-scale, and sites in longer-unburnt vegetation had more species.

Although areas burnt in prescribed burns supported lower bird diversity compared to long-unburnt areas, prescribed burns are still necessary to reduce the risk of extensive wildfire. Such burns should focus on breaking up areas of high fuel at the beginning of the dry season (Fig. 4). The extent of long-unburnt vegetation that can be maintained with careful fire management is yet to be determined, but its importance as bird habitat is clear.

Acknowledgements: This work could not have been completed without funding and logistical support provided by AndyInc Foundation, Bush Heritage Australia and UQRS. Thanks to Peta Mather and Donna Oliver who assisted with field work. This study was carried out with approval from the Animal Ethics Committee at the University of Queensland (approval no. SGPEM/325/11/UQ).

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Contact: Dr Emma Burgess University of Queensland, Email: e.burgess4@uq.edu.au

[This project summary is a precis of a talk presented to the Nature Conservation Council of NSW’s 10th Biennial Bushfire Conference, ‘Fire and Restoration: Working with Fire for Healthy Lands’ 26-27 May 2015. For full paper see: http://www.nature.org.au/healthy-ecosystems/bushfire-program/conferences/%5D

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Posted in Fauna & habitat, Fire Ecology & Management, Landscape pattern & design, NCC 2015 Fire and restoration conference, Queensland, Restoration & management theory, Sclerophyll communities, Techniques & methodology

Prescribed burning provides opportunities for site restoration via weed management in the Mount Lofty Ranges, South Australia

Posted on 2 December 2015 by | Comments Off on Prescribed burning provides opportunities for site restoration via weed management in the Mount Lofty Ranges, South Australia

Andrew Sheath

Introduction. The purpose of much of the prescribed burning work we do in the Mount Lofty Ranges in South Australia fuel reduction to mitigate the risk of bushfire. But we also do a lot of work, including burning, purely for the purpose of biodiversity conservation. Being so close to Adelaide all of our Parks are highly fragmented and have a strong history of disturbance such as mining and grazing.

Within our team we have a very strong focus on weed control and we do this routinely for all of our burns. There are two reasons we have such a focus on weed management and no longer just go in and burn and walk away. The first is to ensure that the vegetation condition does not deteriorate and the second is to ensure that fuels don’t increase due to woody weeds. In many cases this is leading to improvements in quality of the sites.

Methods. Our burns are done under a prescription which specifies certain weather parameters for which the burn can be carried out safely. Our sites are typically between 5 and 200 hectares, often adjacent to built assets (Fig 1). Mapping both before a burn and 4 years after a burn allows us to monitor progress. We map most of our burns on foot, assessing native vegetation condition, weeds present, their distribution and their cover throughout the proposed burn site. We undertake this with a view to gaining a clear picture of what we’ve got to deal with during the burn and post-burn. Our planning begins 6-18 months prior to a burn to give us plenty of time to carry out works that are often seasonally dependent.

Fig 1: Example of a typical Adelaide Hills conservation area on the urban fringe. Red areas show prescribed burns either completed or in the planning phase.

Fig 1.  Example of a typical Adelaide Hills conservation area on the urban fringe. Red areas show prescribed burns either completed or in the planning phase.

Examples and results to date. In most of our situations pre-burn control greatly increases the efficiency of any post-burn work and overall makes our work easier.

Example 1: Figures 2 and 3, shows a significant reduction in the distribution of Gorse (Ulex europaeus) at an otherwise relatively intact site after the burn, improving the condition of the bush in this area.

Fig 2. Gorse distribution and density pre-burn

Fig 2. Gorse distribution and density pre-burn

Fig 3: Gorse distribution and density 3 years post burn after control work

Fig 3. Gorse distribution and density 3 years post burn after control work

Example 2: Figure 4 shows successful tree heath (Erica arborea) control in an otherwise intact woodland in the Adelaide hills. Six months prior to burning we cut and disturbed the stand of Tree Heath on this site to ensure all the biomass would burn; that we wouldn’t have the adults sitting up high above the flame dropping seed onto burnt ground (which often happens when burning under mild conditions); and, to promote juveniles which would then be burnt and killed during burn. The other benefits of this approach are that it also promotes native germination and makes follow up, post-burn easier.

Fig 4: Erica control site showing before being burnt or cut, after being cut and post burn.

Fig 4: Erica control site showing before being burnt or cut, after being cut and post burn.

Fig 5. Erica post control and pre-burn

Fig 5. Erica post control and pre-burn

Fig 6. Erica post-control and post-burn

Fig 6. Erica post-control and post-burn

Example 3: Figure 5 shows a perched swamp in the Adelaide Hills being thickly invaded by Wonnich (Callystachys lanceolata) from Western Australia. Because of location of the site we were unable to burn the swamp at sufficient intensity to consume the Wonnich. So in this situation we burnt the surrounding area in spring in mild conditions within prescription. We later went back in autumn after we had dropped all of the Wonnich on the ground and we burnt that swamp at a very high intensity and consumed all of the biomass. That promoted mass-germination of the weed. We’re then dealing with one age-class and we can go through and hand weed, spot spray, and re-burn areas to control the germination. Joe Quarmby, Threatened Flora Ecologist, was the mastermind behind this burn and continues to drive follow up control work at the site.

Fig 7. Swamp burnt in drier conditions during autumn.

Fig 7. Swamp burnt in drier conditions during autumn (after surrounding area burnt in more mild conditions in an earlier season).

Follow up control work in swamp.

Fig. 8. Follow up control work in swamp.

Lessons learned. Burning can be a very useful tool for weed management and although no site is ever the same we have been able to use a variety of techniques for certain weeds which greatly increase our efficiency. The key point however is that weed control should be and is routine and needs to be thought about pre-burn.

Acknowledgements. Thanks is extended to Joe Quarmby, Threatened Flora Ecologist.

Contact: Andrew Sheath, Department of Environment Water and Natural Resources – South Australia. Tel: +61 0457 512 032, Email: Andrew.Sheath@sa.gov.au

[This project summary is a precis of a talk presented to the Nature Conservation Council of NSW’s 10th Biennial Bushfire Conference, ‘Fire and Restoration: Working with Fire for Healthy Lands’ 26-27 May 2015. For full paper see: http://www.nature.org.au/healthy-ecosystems/bushfire-program/conferences/%5D

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Posted in Fire Ecology & Management, Grassland/grassy understorey, NCC 2015 Fire and restoration conference, Sclerophyll communities, South Australia, Standards, Techniques & methodology, Urban ecosystems, Weed issues & solutions

Operational planning and logistics – introducing fire into the landscape

Posted on 18 November 2015 by | Comments Off on Operational planning and logistics – introducing fire into the landscape

Robert Strauch

Eastern Suburbs Banksia Scrub (ESBS) is an Endangered Ecological Community that only exists in the eastern part of the Greater Sydney area – between North Head and La Perouse. From an original estimated area of 5300 hectares there’s only 146 hectares of this community left. From the 3% that’s actually left only 18% of that ESBS is on managed lands. A lot of it is in areas like golf courses, people’s backyards along coastal parts in the Sydney eastern suburbs and small pockets on Council reserves, most locations of it are quite sparse in area, with the North Head community being the largest portion in total area remaining.

In 2004, the key stakeholders developed a recovery plan for ESBS, with National Parks working with other land management agencies to try and protect and manage this community. One of the recommendations from the plan was high intensity burn at an 8-15 year rotation.

Fire and Rescue New South Wales (NSW) are re-introducing fire as a tool to restore ESBS at three sites: broad area burning at North Head, some windrow burning at La Perouse on the site of the NSW Golf Course and pile burning at Centennial Park in the Moore Park area. This involved three types of burns: an area burn, windrows and burn piles.

Fig 1. Broad area burning at North Head

Fig 1. Broad area burning at North Head

1. North Head

A burn was conducted at North Head, Sydney Harbour in early September 2012. This was done in collaboration with National Parks and Wildlife Service, the Sydney Harbour Federation Trust and also the North Head Sanctuary Foundation. Interestingly, the location of the fire is very close to the location Dr Geoff Lambert has identified as the site European people in Australia first recorded their observations of fire being used by Indigenous people on the 28th May 1788.

Methods and risk management. At North Head, three relatively small burns were conducted: third quarantine cemetery (0.8 ha), North Fort (1.5 ha0 and Blue Fish Drive (1.8 ha). These involved very high levels of operational logistics and operational planning, prior to waiting for the appropriate burn conditions.

(a) Public safety. Because of a history of fires getting out of control at North Head, precautions involved restricting public access to the headland, which meant confining all three burns to 1 day to minimise disruption. There was an overall incident controller, Superintendent Kel McNamara for the North Head complex, plus divisional commanders in charge of each of the burns. The divisional commanders essentially were running their individual burns managing their operations officers and resources required. From this we ended up with 10 firefighting appliances (trucks) and (including the incident management and logistical appliance) we had a total of 36 resources contributed by three agencies: Fire and Rescue NSW, National Parks and Wildlife Service and Rural Fire Service Pittwater-Warringah. With all of that we had 121 fire fighters for our very small sites. State Emergency Service assisted us with closing down walking trails and making sure people weren’t actually coming onto the headland. We had a fire truck (Flying Pumper) sitting there as if it was in a fire station, so if any spot fires occurred they could go and deal with the fire and we could still carry on with our prescribed burning that we were undertaking.

(b) On the day of the burns there were 400 kids on the headland, which was worrying. I tried to encourage them to go into Manly for the day but they wanted to stay on the headland for their planned activities at the Quarantine Station. Because of that I then had to go through steps in the local emergency management plan and arrange with Sydney Ferries to make sure there was a ferry ready and available in case we needed to evacuate the headland as we could only evacuate by water. Also we had to speak with Harbour Control in case the fire got away and we had to shut down the shipping channels coming into Sydney Harbour.

(c) Heritage protection. We obtained mitigation funding through the NDRP National Disaster Resilience Funds to do some mitigation work around North Head’s historical stone walls criss-crossing the headland. This involved some clearing along those walls to protect the historical significance of them and this clearing doubled to create a strategic fire advantage zone over the headland.

(d) Miscellaneous risks. Among the other things I had to deal with was underground ventilation. There’s historical war tunnels through North Head with ventilation intakes that I had to make sure were covered and insulated so we weren’t dragging smoke into the underground tunnels, increasing the carbon monoxide load down there. This was so if people walked in there after the burns they weren’t going to asphyxiate themselves. The bonus carry over from Defence was possible unexploded ordinance out on the headland. Furthermore, the Sydney Water treatment plant opposite the blue fish drive burn involves an above-ground storage tank of highly explosive biogas.

(e) We could only burn in certain seasons. The breeding seasons of the Endangered population of Long-nosed Bandicoot (Perameles nasuta) and also the penguins had to be considered. This also involved working in with studies of these that were being done by the University of New South Wales, researching the bandicoot’s pre and post-fire introduction. Then we had to put in a notification strategy. The weather window, given all the other constraints, was very narrow. We put out an email notification system where we were literally going to give people anything from 24 hours notice up to 48 hours notice to actually go ahead with the burn.

This high level of risk meant that I had to win the confidence of senior management of Fire and Rescue NSW to support the burn. We did get that support as well as support from all the other land managers, which was fantastic.

Burns themselves. In terms of the burns themselves, once the fire got into the burn area it developed to very good intensity. It was a very high fuel load situation and one interesting challenge was to try and stop the fire fighters from putting the fires out. The buildings were quite close and they were very small parcels of burns.

Ecological context. The burns that we did on North Head involved a range of experimental treatments that included burning, controlled thinning and untreated controls; with some sites fenced from rabbits, a study conducted by Dr Judy Lambert.

We burnt on a small scale to start with to see what type of regeneration we were going to get from broad area burning out on the headland. The regeneration that we’re getting out at North Head is outstanding. But the biggest problem that we have is the newly sprouted post fire vegetation degradation from rabbits and the bandicoots. So we suggest for any burning in ESBS, the advice is that it needs to be fenced post-burn to encourage the regeneration to thrive.

Fig 2. High biomass vegetation before burn, North Head

Fig 2. High biomass vegetation before burn, North Head

Fig 3. During burn at North Head

Fig 3. During burn at North Head

Fig 4. Water deliver from air, North Head

Fig 4. Water deliver from air, North Head

Fig 5. Mopping up after burn at North Head

Fig 5. Mopping up after burn at North Head

2. La Perouse

At the New South Wales golf course at La Perouse the dominant species, Coastal Tea Tree (Leptospermum laevigatum) was cut and dropped on the ground. They let it cure and then they come in and burn it in isolated pockets.  Burning on the golf course is a lot easier than North Head because there are far fewer risks to plan for and manage, and the eastern boundary is the Pacific Ocean. With this type of environment and preparation we can get extremely high intensity burns which are required for the ESBS. Once again the land managers fence the area to stop exposure to rabbits. At the La Perouse golf course site, we had arson this fire season so we had an additional 21 hectares of wildfire. We’ve put measures in place to monitor what introduced fire has done compared with what wildfire has done in the same vegetative area along Henry Head.

3. Centennial Park

Centennial Park, in the middle of Sydney, has an area of ESBS which is not even a hectare. The Park’s owners, the Centennial Park Trust, have been manually clearing weed from the ESBS, piling it and then conducting pile burns on the area, spreading the ash from that. Once again some really good regeneration has occurred there and the burn area is also fenced off to stop rabbits.

That’s our story of how Fire and Rescue NSW has been involved in broad area burning, windrow burning and pile burning, working with land managers for the recovery of Eastern Suburbs Banksia Scrub.

Acknowledgements: Fire and Rescue NSW acknowledge this project could not have happed without the collaboration of National Parks and Wildlife Service, the Sydney Harbour Federation Trust, North Head Sanctuary Foundation, Rural Fire Service Pittwater Warringah, Road and Maritime Services, NSW Police, Manly Council, Sydney Water, Sydney Ports, Sydney Ferries, Harbor Control, Department of Defence and many others.

Contact: Robert Strauch, Bushfire Officer – Metro East Command, Fire and Rescue NSW (Operational Capability, Specialised Operations, Bushfire Section – Level 1, 55 Dickson Avenue, Artarmon, NSW 2064. Tel: +61 2 9901 2445, +61 448 597 547; Email: E Robert.Strauch@fire.nsw.gov.au)

[This project summary is a precis of a talk presented to the Nature Conservation Council of NSW’s 10th Biennial Bushfire Conference, ‘Fire and Restoration: Working with Fire for Healthy Lands’ 26-27 May 2015. For full paper see: http://www.nature.org.au/healthy-ecosystems/bushfire-program/conferences/%5D

Fig 6. Windrows before the burn, La Perouse

Fig 6. Windrows before the burn, La Perouse

Fig 7. Burn La Perouse

Fig 7. Burn La Perouse

Fig 8. Mopping up after burn, La Perouse

Fig 8. Mopping up after burn, La Perouse

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Posted in Fire Ecology & Management, NCC 2015 Fire and restoration conference, NCC Fire and Restoration Conf 2015, New South Wales, Organisations, Pest species, Policy & legislation, Sclerophyll communities, Threatened species & communities, Urban ecosystems

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

Posted on 6 October 2015 by | Comments Off on 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.

 

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Posted in Assisted regeneration, Bush regeneration, Community involvement, Cultural & socio-economic issues & solutions, Fire Ecology & Management, Grassland/grassy understorey, Indigenous land & sea management, NCC 2015 Fire and restoration conference, New South Wales, Restoration & management theory, Weed issues & solutions