Wildfire

Every year, at the end of October, we have a cousins reunion at The Entrance on the Central Coast of NSW. I also had decided to attend the 150th anniversary of Ourimbah School, so we arrived there while bush fires were raging in NSW. We drove through the remains of one of them in the Southern Highlands. My mind went back to the bush fires I had encountered. I grew up in the bush and have a great love of the Australian bush. As a child and young adult I had encountered a number of them. I respect fire but I am not frightened of them.

The worst I faced was on Ash Wednesday in 1980. At that time I was developing Warrawong Sanctuary. The local Fire Captain was not impressed with my planting bush back on the cleared farm. He had told me that if there was a fire, then he “wouldn’t send in good men to die”. And what a fire there was to be.

The burn at the local dump had broken out. The fire was in the bush south west of Warrawong Sanctuary about 500 metres away. The wind was gaining pace. It was a south-westerly. Warrawong was on the north-eastern corner of the intersection of Stock and Williams Road. Stock Road runs east to west. Williams Road runs north from Stock Road forming a T intersection. They had cut a track with a bulldozer continuing Williams Road to the south.

Longwood Road runs north to south about 300 metres west of Williams Road. Three fire trucks were stationed on Longwood Road to stop the fire from crossing Longwood Road at Longwood. A fire truck was stationed on Stock Road about 50 metres west of the Stock/Williams intersection. I was stationed on the track that was cut extending Williams Road. I had a tractor with a 44 gallon drum of water with a pump running from the power take-off. There was a hose attached with a nozzle. It was getting very hot. It was mid-afternoon.

The crew on the fire truck on Stock Road, shouted something to me and jumped into their truck and vanished. I didn’t hear what they said but later I was to learn they had lost two fire trucks on Longwood Road. They had received a radio message to go. The wind was getting stronger and it was getting hotter. Suddenly a wall of flame came over the brow about 100 metres away.

The paddock that I was in had been very heavily grazed. It seemed to explode. The fire was now in the bush to my east. My jeans were burning. I pressed the nozzle. I put out my jeans. I was supposed to stop that and I hadn’t even got my nozzle turned on. I moved my gear to Stock Road. It was now my job to keep the fire out of Warrawong Sanctuary. I was confident that I could. The wind was now blowing from the south. It was blowing burning embers onto Warrawong. The smoke was dense. It was hard to understand what was going on. I just concentrated on putting out the fires on the southern edge of Stock Road producing the embers threatening Warrawong Sanctuary.

My water drum was empty. I went back into Warrawong Sanctuary to fill up. The power was off. I had to siphon water out of a concrete tank. I heard a car stop in my driveway. I wandered round. It was a police car and two policemen. One of them said, “This house is going to go. We may as well save what we can”. They had parked their car in a way which would block my way out. I said, “I don’t give a fuck what you do, but if that car is still there when I come out I will drive over it. I went back and finished filling my tank. As I left I noticed that they had moved the car and was filling it with their loot. There was nothing in the house worth pinching. I had spent all my resources developing Warrawong. It would be five hours before I saw another soul.

The rain came at about 11pm. I collapsed onto my bed. Warrawong was safe. There was to be another big fire three years later. Again my neighbours were burnt. Warrawong Sanctuary was saved. The Fire Captain who had threatened me over three years before said to me, “Well John, there are some things I don’t understand.” “Yes”, I replied and wandered away. As I drove through the Southern Highlands thirty years later I mused, “Nobody has learned anything”.

Let me start by trying to explain the bush. Just like your garden, the bush responds to the management it receives. Its management is by the animals that live in it, the people who use it and the environment itself. When Europeans settled the Australian bush it was described as “grassy woodland”. In 1851 Hugh Proby wrote home to his father in England about the bush in the Adelaide Hills, “ There is most excellent turf for riding growing at the top of the hills, and although it is necessary to make a long round to avoid some precipitous glen, yet without difficulty you can go along on most excellent cantering ground for any distance” ( An Earl’s Son – The Letters of Hugh Proby by Louise Neal). Try cantering a horse through your local national park. And: http://www.rfs.nsw.gov.au/file_system/attachments/State/Attachment_20050308_44889DFD.pdf
“It is generally accepted that the forest which grows in Australia today is very
different to the forests which existed before European colonization. Writings of a wide selection of early colonists and explorers describe the forests very open, so open as to be frequently likened to parkland. The trees were very often large and well spaced, with native grass and very little undergrowth, there was usually no need for people to clear tracks for their horses and drays.”

Today our bush is “shrubby woodland”. Let me explain the difference. Grassy woodland has little to do with grass. It is like the add we had on oil. It said “oils aint oils”. I was wandering through our local Bunnings store recently. In the nursery section there was a bench about 20 metres long labelled “grasses”. There was not a grass among it. There were lomandras and there were sedges but there were no grasses. The grass in “grassy woodland” described the look of it, not the actuality. This is important. Here in the Aldgate Valley about 80% of the natural species were small plants. About 16% were shrubs and about 4% were trees. About 15% of the small plants were grasses. Never-the-less we describe all these small plants as grasses in the “grassy woodland” because they give a grassy effect.

Since fire intensity is important when talking of loss of assets or life, I would like to define various fire intensities. I would like to do this by describing the effect the fire has on the bush. More importantly the leaves on the trees themselves. I will describe a low intensity fire as one which leaves the tree leaves alive and green. A medium intensity fire will leave the leaves intact but dead. They will soon brown and fall. A high intensity fire will leave no leaves on the trees, either alive or dead. A high intensity fire can only occur if there is enough fuel , on the ground, to produce the heat. It would be a rare event to have other than a low intensity fire in real grassy woodland.

Of course there are a number of factors which affect the intensity of a bushfire. There is air temperature, humidity, wind and terrain. However we have little control over these. Where we do have control over is fuel. So let me talk about fuel.

To do this we have to start with plant cycles. Most plants go through different cycles depending on the seasons. They grow, they flower, they fruit, they seed and they rest. Many plants, such as orchids and lilies, may disappear totally to rest. They absorb all the nutrients from their stems and leaves and simply disappear into their bulbs safely underground. Other plants die back leaving dry brown leaves such as winter growing grasses. Others stay evergreen. However, some of these can be very flammable on a hot dry day. The important thing is the diversity of the plants in a forest with some green and growing while others resting.

This brings us to the importance of diversity. For example, if we have a monoculture of a particular grass which dies and turns brown in summer, then this would present a very high fire danger indeed. If we had a monoculture of a certain shrub which rested in summer and therefore was highly inflammable, then this would also present a high fire danger. I remember when the Ash Wednesday fire in 1980 travelled from Longwood to Mylor. The distance was three kilometres. The vegetation, in the Leslie Creek Valley was a monoculture of Erica arborea. The fire took less than ten minutes to travel the distance in a series of explosions.

Two hundred years ago the Australian bush was full of animals. Kangaroos grazed the grasses. Wallabies grazed any shrubs that appeared in the grassy woodland. Lyre birds, scrub turkeys and echidnas turned over the ground litter looking for food and assisted in the rotting down of litter. Bettongs dug in the ground looking for fungi and germinating seeds. When Europeans settled Australia they bought with them foxes and cats. One old bushman, describing his bit of bush when the fox came, told me, “The bush went quiet”. Today there are few animals indeed in our bush.

In fact Australia has a very poor record when it comes to wildlife management. For example, according to the I.U.C.N. there are 733 species of animal, in Australia which are critically endangered, endangered or vulnerable to becoming endangered. http://data.iucn.org/dbtw-wpd/edocs/RL-2009-001.pdf . For the world, the number is 8,462. This means that 8.66% of the world’s species likely to become extinct in the near future are Australian. Our answer to this is to spend $125 million per year on biodiversity. Compare this with climate change, nowhere near as important as loss of species. Australia produces 1.5% of greenhouse gasses. In this case we are happy to spend billions of dollars per annum on reducing them by 5%.

Similarly there has been a massive loss of plant diversity. The list of extinctions, endangered and threatened plant species hides the true state of affairs. For example when I first bought the property, which was to become Warrawong Sanctuary, in 1969 there were 45 species of orchid growing along the edges of Stock Road. I photographed them at the time. You can see the photographs at http://www.johnwamsley.com/july01.html . Stock road is 3 km long and runs from Heathfield to Mylor. Today there are only a few species left along Stock Road. However, the species which once grew along Stock Road can still be found further away. Similarly there were once over 600 species of plants growing in the Aldgate Valley. If you don’t count the ones growing at Wirrapunga, there are less than 300 species today. Again all these species can be found further away.

Although there are no recorded extinctions of any plant species in South Australia, the diversity of plants on any given hectare has dropped substantially. Once there would have been hundreds of species growing on each hectare. Today you are lucky to find fifty. More often about twenty and sometimes a virtual monoculture. This just means that as the numbers of a species declines you simply spend more time looking for them. The records therefore, give a very false impression of the real facts. This is extremely important when discussing bushfires.

There is clearly a correlation between the lack of biodiversity and the intensity of bushfires.

Aborigines set fire to the bush, wherever it would burn, to assist with catching food. They would soon realise that the areas they burned sprung to life and produced bush tucker like Yam Daisies and Native Potato. There is no doubt that they took a great interest in caring for the bush. Their very existence depended on it.

http://www.publish.csiro.au/onborrowedtime/docs/PCB_Ch11.pdf
“Aboriginal people use fire for many reasons:
• to smoke out animals such as possums and gliders from trees (Kerle, 2001; Lindenmayer, 2002b) or to trap smoke-tracking species such as some types of raptors (Boekel, 1980)
• to encourage the development of grasses for herbivores such as Kangaroos (Johnson et al., 1989)
• to stimulate the growth of particular food plants (‘firestick farming’, sensu Jones, 1969)
• as part of warfare (Martin and Handasyde, 1999)
• to communicate (by signalling; Jones, 1969)
• to clear paths for travel
• to manage fuel loads and landscape mosaics of woodlands and rainforests (Langton, 1998).”

When this management changed with European settlement, the shrubs took over our bush. The litter no longer fell to the ground where it could rot down. It hung up in the shrubbery. The shrubs formed dense masses. No longer could a horse be cantered through the bushland. It is now difficult to even walk through it. The fuel loads increased considerably. Fires, therefore, were no longer low intensity fires. The age of the holocaust was with us.

There are many publications which give a history of fire and its effects using pollen and charcoal deposits. See for example:
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2745.2006.01140.x/full

There are some who argue that fire can be used to reduce fuel loads. This is a very dangerous path indeed. There is a great difference between using fire in grassy woodland full of biodiversity and wildlife to assist the regeneration of grassy woodland, to using it in shrubby woodland devoid of wildlife. The fire merely assists the growth of plants which enjoy fire. That is what evolution is all about.

Another element has been introduced to our bush. Europeans not only brought animals such as foxes and cats to wrought damage to our bushland, they also brought their plants. Many of these have escaped into our bushland. Many enjoy fire. For example most of our native grasses are summer growing and therefore remain green in summer. They evolved to survive our hot summers. They do not grow as densely as the grasses we introduced to feed our stock. Introduced grasses generally grow in winter and die back in summer. A monoculture of dead grasses can be extremely volatile. When a fire burns in our bush in spring, it kills the native grasses together with their unripe seeds. The introduced grasses have buried their seeds in the soil and died. The fire therefore promotes these introduced grasses. Unless a fire is correctly followed up by careful removal of unwanted species, all we are doing, by burning, is solving the problem in the short term but making it worse longer term.

It is interesting to go and look at a line where housing meets the bush. If you walk from the boundary into the bush, the fuel loads are greatest near that boundary. In fact it generally reduces as you move further into the bush. The reason for this is twofold. Firstly, the adjoining gardens have crept into the bush where nobody cares for them. Secondly, there is a management in place which favours heavy fuel loads. It is as simple as that. The very management of this strip of land, in the name of fuel reduction, actually promotes fuel. While residents’ memory, of the last fire, is strong the scrub will be faithfully cleared. But, as memories fade the fuel comes back stronger than ever, revitalised by the positive gardening it has received.

There are some who claim that climate change is the cause of recent bushfires. There is no doubt there is climate change and this may well make matters worse. It would be surprising if there wasn’t. However, climate change is a slowly changing thing. It is over 50 or 100 years, not this year.

There is one other interesting point which needs to be understood. On a day of severe bushfire risk then houses, built close enough together can pose just as high a fuel load as dense scrubby bush.

It was interesting to note that the only house lost, in Stock Road in the 1980 Ash Wednesday fire was a brick house, with a tiled roof, situated in the centre of a one hectare block which had been completely cleared of all vegetation. Vegetation is important. It reduces the wind. It catches the embers. But! It is important that this vegetation be based on grassy woodland.

Finally it is important to understand a basic fact. If your house is prepared so that no embers can enter within or under your house and if the bush is properly maintained grassy woodland for a distance of 100 metres from your house, then you need not fear a bushfire.  If this is not the case then you should read “Essential Bushfire Safety Tips” by Joan Webster OAM, published by the CSIRO. This is an excellent book for those who are not interested in our natural environment or maintaining our biodiversity.