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  • Landcare, caring for country Liddy Nevile

    [email protected]

    Introduction Australia is an old country and its environment is fragile. Aboriginal practices have supported inhabitants for millenia, possibly with significant evolution of the environment, but in the last two hundred years the environment has significantly changed and, in some cases, been destroyed or rendered dangerous. However climate change is relevant, severe fire events are not infrequent and the flora and fauna have significantly changed.

    This talk aims to draw attention to the difference between the old and new land use practices and ask if the immigrants of the last 200 years might be able to learn from their predecessors. In particular, the role fires and associated practices can play in the environment will be considered as a way of drawing attention to and interpreting land care and caring for country.

    Early European paintings of Australia show it as a land with open ‘grazing’ spaces in which hunting was easy; with bio-diversity, and safety from what is now greatly feared in Australia, uncontrollable fire.

    Image 1: Painting by Eugene von Guerard, , ABC Firestick Ecology1

    Image 2: Painting by Eugene von Guerard, ABC Firestick Ecology2

    For a long time it was believed the early painters were simply seeing the new land through their ‘old’ lenses, imaging it as they saw the mother country. Recently, northern hemisphere visitors attested to such a temptation when they commented on the problem they saw with many

    1 from http://www.abc.net.au/local/photos/2015/09/14/4312198.htm 2 Op cit.

  • indigenous Australian trees having bark only up to a certain height. They wondered how the forests maintained their canopy.

    Image 33

    Today, it is slowly being recognised that those early painters were painting what they saw, and that the land had been ‘treated’ to provide those useful open spaces. The Aboriginal practice of using fire as a tool for agriculture rather regarding it as an unpredictable, arbitrary risk and enemy, has been credited with this achievement. The role of open grazing has also been recognised.

    A friend of the author relates that his grandfather used to ‘slow burn’ their farmland. He claimed that his neighbours did not ‘approve’ so in later years, early in the season he simply dropped some ash from his pipe in a strategic location and then took a while to get around to dealing with it – knowing that by the time he did, his mission would have been accomplished and slow burn would be underway. His grandson recalls it as controlled, deliberate, slow burning.

    Australia is subjected to very savage bushfires these days – every year, huge areas are burnt beyond repair by hot, in fact increasingly hotter, fires. These hot fires race up hillsides, supported by increasingly strong winds it seems, but they also jump, as inflammable eucalyptus gas clouds. Many of the alpine forests where modern Australians ski are now gone. The last fires were so hot they burnt the trees and the seeds and now it is not even possible to plant new forests because the native trees will not survive without the protective cover of older, bigger trees.

    Today, somewhat ironically, many Australian native plants cannot be propagated unless they are associated with fire somehow – by being heated or by being wet with water that has smoke infused in it, or something similar.

    Biodiversity degradation The evolution of the landscape occurs surprisingly quickly.

    3 from https://i.pinimg.com/originals/12/4f/58/124f58582b3c2c2fd86128c0e6705802.jpg

    https://i.pinimg.com/originals/12/4f/58/124f58582b3c2c2fd86128c0e6705802.jpg

  • Image 4: ABC Firestick Ecology4

    Vic Jurskis, an expert forester, points to the many exposed tree trunks and branches in an area as dipicted in Image 4, as typical of sick trees in a declining forest due to a lack of burning and also a lack of grazing, which he says has similar benefits to traditional burning:

    The process begins with the lack of fire, seedlings grow into bushes; mulch accumulates; soil conditions and microclimates change; nitrogen accumulates in the soil; tree roots deteriorate; and as the trees get sick they lose their foliage and that lets more light in and the understory thrives; that's a vicious cycle; pests flourish that eat any part of the tree, the leaves and the roots - because sick trees are better food. (Brown, 20155)

    Image 5: ABC Firestick Ecology6

    In Image 5, the red gum to the left has been fenced off and is surrounded by saplings, and the one to the right is in a grazing paddock. Jurskis says the comparison of the crowns shows that the tree in the grazed paddock is obviously more healthy. The image shows an example to support the theory that trees decline unless undergrowth is controlled and nutrient cycling is maintained by burning or grazing.

    4 Op cit. 5 From www.abc.net.au/local/photos/2015/09/14/4312198.htm 6 O p cit.

    http://www.abc.net.au/reslib/201509/r1474147_21578722.jpg

  • Images 6: , ABC Firestick Ecology7

    In Images 6, Jurskis is looking up at a dying ironbark that is covered not with foliage but with parasitic Mistletoe. The tree is surrounded by uncontrolled Pittosporum and native cherry that is a parasite on the tree's roots. Jurskis says that traditional Aboriginal burning kept forests clear of such undergrowth.

    Image 78

    Soon enough, Jurskis says, instead of an open grassy forest with spaced trees and wider crowns and open, grassy understory, and easy walking, the crowns of the spotted gums are thinning, they have epicormic growth, and they haven't got mature leaves out on the ends of the branchlets where they should be (Image 7). The crown is sort of receding down onto the branches as shown in Image 8.

    Image 8; ABC Firestick Ecology9

    7 Op cit. 8 Op cit. 9 Op cit.

  • Image 9: ABC Firestick Ecology10

    Jurskis says Image 9 shows a forest in the last stages of tree decline. He says a thick under-storey has developed because of a lack of burning, leaving the trees vulnerable to pests, parasites and diseases.

    The survivors are still there. The dead trees aren't obvious because they've broken down. It's quieter because the bellbirds have 'moved on to where there are more sick trees in the earlier stage of decline’.

    The ‘space’ vacated is then filled:

    Image 10: ABC Firestick Ecology11

    For Jurskis, the final stage of tree decline is the invasion of wattle scrub (Image 10). "Because declining trees don't carry seeds then the site has reverted to wattle scrub." And that's how it will stay.

    The wattles produce hard seeds that persist in the soil so when the current stand dies of old age or gets burnt by a high intensity fire, then we'll get a new wattle scrub.

    Jurskis says this is an example of how allowing forests previously managed by Aboriginal burning to turn to wilderness ends up destroying biodiversity.

    10 Op cit. 11 Op cit.

  • Image 1112

    Despite the fact that epidermic shoots will sprout vigorously from under bark that has been lightly burnt, the recovery of forests after serious fires is not good. Note that in Image 11, the canopy has been fatally burnt.

    Protecting diversity Insight SBS featured Victor Steffensen, an Aboriginal fire expert:

    Each year rural fire services across the country carry out vast swathes of back-burning and hazard reduction, but Steffensen says this is entirely the wrong approach: the fires tend to burn inward, creating an inferno from which animals cannot escape and a heat so strong it burns both undergrowth and canopy.

    Indigenous burning, on the other hand, is cool: temperatures remain low so flames never reach the canopy.

    “The canopy is [a] whole other world,” says Steffensen. “The canopy is so important to us because that's the life of the flowers, the fruits, the birds, the animals … that top canopy is very, very sacred and the simple rule is that it never burns.

    If you burn the canopy, then you have the wrong fire. Fire [should] behave like water, trickling through the country [so] it doesn't burn everything.”

    Traditional burns are also started from ‘fire circles’ and patterns that allow the fire to spread out in a 360 degrees radius. This allows animals to escape as they smell the smoke and keeps temperatures down, with only one fire front to manage.

    Steffensen says this kind of fire knowledge has been lost over the centuries, both as a result of colonisation – the diffusion of knowledge throughout the stolen generations, the introduction of non-native weeds that spring up when the canopy burns – and of our migration towards cities. Even European pastoralists knew how to manage the land with fire, he says.”

    The author spent a day with Steffensen, Aboriginal Elders and forestry experts in Victoria learning about cool fires. Participants were shown how trees limit the height to which fires can burn without damaging the trees and, in fact, with the cool fire cleaning their trunk and offering propagation opportunities to seeds in the surrounding area.

    12 from https://en.wikipedia.org/wiki/Bushfires_in_Australia#/media/File:Bushfire_damage.jpg

  • Might it be that the trees have short bark coverage to deal with fires, by any chance?

    Image 1213

    In fact, many long-lasting Australian trees only have heavy bark for a short distance up their trunk. An Elder described how the bark of the tree in Image 12 controls the movement of air up the trunk and so actu