A heathland reserve on the New South Wales south coast has come back to life after being scorched by bushfire in August 2018, and local land carers are praising the role of fire in maintaining the environment's biodiversity.

Key points: The South Pacific Heathland Reserve was burnt by arsonists in August 2018 and now many plant species have rejuvenated

The South Pacific Heathland Reserve was burnt by arsonists in August 2018 and now many plant species have rejuvenated Reserve volunteers say the Indigenous method of cool mosaic burning plays an important role in maintaining the native environment

Reserve volunteers say the Indigenous method of cool mosaic burning plays an important role in maintaining the native environment One firefighting veteran says there's "merit" in Indigenous burning methods when applied in combination with academic knowledge

The South Pacific Heathland Reserve near the seaside town of Ulladulla is 14 hectares set within a cliff line and a suburb, with an extraordinary amount of plant diversity in a relatively small area.

The landscape, which has been nurtured by volunteers since the 1960s, is made up of several vegetation types including wet heathland, sand heath, and coastal woodland.

In August last year the area was set alight by arsonists.

Annie Boutland at the South Pacific Heathland Reserve. ( ABC Illawarra: Sarah Moss )

"In the centre of the reserve where the heathland is we've had a number of fires over the past decade," said environmental scientist Annie Boutland, who is in her final months as chairwoman of the board of land managers for the reserve.

"What we are looking at today is several stages of post-fire regeneration.

"What we've ended up with, somewhat by accident, is a mosaic of burn. We have areas that were burnt only eight months ago, some two years ago, and some three."

Mosaic burning is the deliberate burning of patches of land, which has been used to enhance biodiversity.

The method, primarily utilised by Aboriginal people, reduces the chance of large, 'hot' fires by replacing them with 'cool' burnings where isolated patches of land are targeted to include the vegetation and terrain types.

"One of the key things about the burn is that it increases the biodiversity because, in this particular environment, what happens without fire is that you end up with a dominance of the casuarinas," Ms Boutland said.

Without fires to maintain them the casuarinas become thick and make the space uninhabitable for other plants. ( ABC Illawarra: Sarah Moss )

Healthy headland heathland

Ms Boutland said one of the reasons the reserve was so diverse was because of "different and overlapping vegetation types".

"We've also got a cliff face dropping down to the sea, which has its own special plants and ecosystem."

A recent ecological study undertaken at the heathland environment by author Nicholas de Jong identified 340 unique species of plants, placing the environment alongside a rainforest in terms of biodiversity.

More than 100 bird species have also been sighted from Ulladulla's headlands.

"With such a diversity of species-rich plant communities comes a myriad of food sources, nesting materials, and secure, safe places for birds to seek shelter," de Jong said in his 2017 book, Heathlands: Walks and wildflowers of the Ulladulla Headland.

The fragrant tick bush, or Kunzea ambigua, grows in both dry and wet heathland in the reserve. ( ABC Illawarra: Sarah Moss )

'The more you burn, the less you burn'

Ulladulla's headland plant communities: Dry heathland on sand

Dry heathland on sand Wet heathland on clay

Wet heathland on clay Tall heathland dominated by banksia shrubland

Tall heathland dominated by banksia shrubland Tall heathland dominated by sheoak shrubland

Tall heathland dominated by sheoak shrubland Mallee

Mallee Woodland

Woodland Hanging dry heathland

Hanging dry heathland Hanging wet heathland

Hanging wet heathland Hanging swamp

Hanging swamp Coastal sand dune zonation Source: Nicholas de Jong, 2017

As climate changes and periods of drought extend across seasons, the window of opportunity to implement any fire management on the reserve is reduced.

Horticulturist and treasurer of the reserve's land managers' board Robyn Russell has been responsible for maintaining fire management on the reserve for the past few years.

"This last season has been so dry that the window of opportunity is so short and some places here have never had a burn, at least for a long time," she said.

"Local Indigenous people commented 'The more you burn, the less you burn', which I find comforting because I worry about the carbon release during fires but they clearly have another viewpoint worthy of consideration.

"Essentially they are saying that the more you burn the less build-up happens and therefore you get less of that tree-top voluminous stuff that's roaring and dangerous, and killing everything."

After attending an Indigenous Firesticks workshop in Ulladulla, Ms Russell said she learnt about cultural burning that is implemented through the Indigenous methodology of cool mosaic burning.

She said the mosaic burning method was ideal in the reserve environment where many plants required fire to release seeds.

"Chris Palmer, a representative from the Rural Fire Service, admitted that the Indigenous method of cool burning was a gentle method for the bush and plants that need fire," Ms Russell said.

The yellow-tailed black cockatoo thrives in the sheoak shrubland in the reserve. ( Supplied: Linda Slinger )

"But [he said] bureaucracy has his hands tied in paperwork when it comes to protection of assets."

Mr Palmer, an Ulladulla fireman for 30 years, is currently working with Indigenous Firesticks official Victor Steffenson presenting academic papers at conferences. One paper addressed best practice for blending traditional fire burning practice with academic rigour for best outcomes.

"I'm in the fire service, Victor is a [fire] practitioner," Mr Palmer said.

"I've been seeing what's going on and there's merit in the work that's being done and I think we need to look at it as a whole.

"There's traditional knowledge that needs to be shared and there's academic knowledge that needs to be shared, and I think if we combine the two there's a good chance of having the best outcome for the environment.

"It's a conundrum between the [modern-day] way and the Indigenous way, which is a softly-softly approach."

Robyn Russell says fire plays an important role for the reserve's plant communities. ( ABC Illawarra: Sarah Moss )

Ms Russell said the reserve's board of land managers would like to have targeted mosaic burns on the reserves to help particular plant species flourish.

"We would love an Indigenous mosaic burn in pockets that we pinpoint, like the waratahs or flannel flowers, but it's just not easy within the framework we've created — we've snookered ourselves really," she said.

"Nothing occurs naturally or easily here. It's constrained by lots of bureaucratic red tape. I feel sorry for the RFS and people who are trying to implement changes in Aussie bush fire management."

Bushfire has silver lining

The South Pacific Heathland Reserve sits between the cliff line and a suburb. ( Supplied: Google Earth )

Nearly all coastal heath plants are dependant on fire for rejuvenation but the reserve, located between a cliff line and a suburb, hasn't been a part of a larger bushfire for decades.

As the surrounding development prohibits fire events from reaching the reserve, a fire management plan has been essential. However over the past 40 years deliberately lit fires have been frequent, touching large portions of the reserve.

"We've had arsonists light this place up a few times," Ms Russell said.

"It wasn't the right thing to do but the plants have come back, proving to people that these plants live with fire.

"Given the right length of time between firings, nature responds willingly."

After areas of the reserve were set alight in August 2018 not all the plant species have made a comeback.

"The woodier plants take years to grow back, which is why the timing between fires is critical," Ms Russell said.

"A plant like this Banksia serrata can take nine years to reach maturity and make a seed, and it needs fire to release the seed."

The Grevillea macleayana only occurs in small populations in the dry and wet heathland between Jervis Bay and Ulladulla. ( ABC Illawarra: Sarah Moss )

Ms Russell said more emphasis needed to be placed on the role of fire in maintaining the prosperity of Australian bushland.

"The Indigenous people understand the burning process and I think if we all tune in a little bit to their techniques we can find a happy medium," she said.

Ms Russell said practising small areas of mosaic burning was the way to best manage the reserve's diverse landscape, providing it was conducted correctly and under the right weather conditions.

"A tiny patch like this reserve with suburb all around would require 20 people — trained volunteers with Indigenous leaders could burn this 20 square metres, then we all put it out immediately," she said.

"Not today, it's a no-fire day, but you know what I mean."

