Friends of the Box-Ironbark Forests

While we’re on the subject of fire in Box Ironbark systems, it might be worth while recalling important research conducted by scientists at the Arthur Rylah Institute in 2007, and published as Ecological burning in Box Ironbark Forests.  Thirteen years is a long time in a warming and drying climate, but we believe that the document still repays reading, and would recommend it especially to fire managers.

Phase 1 is a Literature Review. The executive summary reads as follows [our emphases]:

1. The review has not been able to shed light on historical aboriginal burning regimes. Some have suggested that seasonal burning was probably undertaken, but little direct evidence exists, and what evidence there is relates to landscape-wide observations that are not site- or vegetation-specific. Fire has probably played a minor part in influencing the vegetation structure and faunal assemblages in Box-Ironbark ecosystems. Management should now be geared towards the needs of the forests as they exist today, not as they existed in some idealised pre-European state.

‘Litter plays an important role in nutrient cycling, and provides important habitat for invertebrates and small vertebrates. Frequent burning…may eventually lead to a depletion of soil nutrients and loss of habitat.’ The problem is that for fire managers litter is fuel: that contradiction can only be resolved by careful and detailed attention to particular sites…and that costs money.

2.The response of the understorey to applied burning will depend heavily on the nature of individual remnants, season, landscape position, soil type, seed bank, disturbance history and susceptibility to edge effects. Some species, particularly leguminous shrubs and short-lived obligate seeders, will be promoted by fire in the short-term. Resprouting species that make up a large proportion of the flora will be little affected unless burning is frequent. Few species rely on fire for germination, and most species that are stimulated by fire will still recruit at a low level in the absence of fire. No species should be lost through burning provided the inter-fire period allows all species to reach reproductive maturity (a minimum of 10-20 years) but absent species are highly unlikely to reappear. Most species will persist even when the interval between fires exceeds 50 years. Further research is required into the germination requirements of Box-Ironbark shrub species, and the effects of applied burning (taking advantage of DSE’s fuel-reduction program). Ecological Burning in Box-Ironbark Forests. Phase 1 – Literature Review Report to North Central CMA 6

3. The response of the canopy will depend on the intensity of the fire. In most instances, fire in small remnants is unlikely to be of sufficient intensity to lead to canopy replacement. In any event, most Box-Ironbark species show continual recruitment in the absence of fire, and thus do not rely on it. In any one patch, the minimum inter-fire period for a fire that kills or severely reduces the overstorey and that allows full recovery of structure is likely to be around 60 years. Further research is required to determine the germination requirements for Ironbark eucalypts.

4. Litter plays an important role in nutrient cycling, and provides important habitat for invertebrates and small vertebrates. Frequent burning (for example, 3-5 year intervals) will disrupt natural processes in the short-term and may eventually lead to a depletion of soil nutrients and loss of habitat.

5. Research into the effects of fire on invertebrates is confounded by high natural variability, and it is often difficult to determine the baseline or climax community. Short-term effects are intimately linked in many cases to burning of the litter layer, and burning at frequencies as high as every three years should be avoided. More research is required into the effects of fire on termites, known to be key drivers of secondary productivity in these forests.

Continue reading →

Here’s something to think about, from Victor Steffensen’s book Fire Country–how Indigenous fire management could help save Australia [Hardie Grant Travel 2020]:

‘When it comes to Aboriginal fire management, the old people didn’t burn every ecosystem. Many people think that Aboriginal people burnt everything and applied fires that scorched large tracts of land. They also think it is like Western hazard reduction, but it is all far from the truth. How could they maintain the diversity of ecosystems and natural resources for thousands of years through the careless application of fire? Aboriginal fire knowledge is based on country that needs fire, and also country that doesn’t need fire. Even country we don’t burn is an important part of fire management knowledge and must be within the expertise of a fire practitioner.’ Page 48

The government is conducting another in its series of Engage Victoria consultations, this one being on the North Central Regional Catchment Strategy 2021-27. Readers may have picked up a touch of cynicism in FOBIF’s approach to these surveys, which we find seriously lacking in attention to detail. In particular, they operate in a kind of vacuum which takes no account of previous work in the area. What, for example, was achieved by the 2013-9 strategy? Or the one before that? Or the numerous other heavy documents on water in the last 20 years? [see our posts here and here]

Reports and strategies keep piling up. What have they achieved?

But hope springs eternal. We suggest you have a go.

The survey can be found here. There will be a regional round table community consultation at Harcourt Leisure Centre hall on Tuesday 17 March from 6.00 to 8,30 pm with a meal available from 5.30 pm. Book here.

We know the land is getting drier—well, most people know. Some politicians and commentators think this is just a passing phase. The rest of us have to deal with it.

On this matter it’s worth quoting some draft findings from the Victorian Government’s Long term water resource assessment.[2019] This process irritatingly divides water use into four categories, including  ‘water for human use [ household, industry, farming]’ and ‘water for environmental use [to keep waterways healthy for us and for native flora and fauna]’. News flash: water ‘for environmental use’ is water ‘for human use’. Separating human and environmental priorities creates unproductive conflicts, and is a practice that should be abandoned.

But there’s informative stuff in the draft findings. They’re for southern Victoria, but we find them eerily familiar. Here are some examples:

‘The assessment found that long-term surface water availability across southern Victoria has declined by up to 21 per cent. Current longterm surface water availability is less than when it was last estimated for the sustainable water strategies… The main cause of declines in surface water availability is drier conditions. Upstream interception of water for storage in domestic and stock dams and plantations may also be contributing to the decline in surface water availability in some basins.’…

‘Water availability for consumptive uses (by people, farms and industry) has declined in most of southern Victoria, with percentage decline varying from 1 per cent to 13 per cent. Water availability for the environment has declined in all basins except the Otway Coast. The percentage decline varied from 4 per cent to 28 per cent, mainly due to declines in above-cap water. Above-cap water is water that remains in a river after limits on diversions have been reached, as well as spills from storage and unregulated flows that cannot be kept in storage.’…

‘In most basins, aspects of waterway health most important for people, animals and plants have not been monitored for as long or as frequently as the assessment needed to identify long-term trends.’ [FOBIF emphasis]

Sound familiar? These and similar realities are what the next North Central strategy will have to deal with.

The harmless, even charming looking plant below is Tribulus terrestris—variously called Caltrop, bindii, cat’s head, goat’s head, yellow vine. It’s a native of North Africa, now naturalised around the world, including Australia. It’s thought to have been introduced here as a contaminant in seed from the Mediterranean area, California or South Africa, and spread widely when its seed was caught in car tyres in the 1920s and 1930s.

Calthrop/Bindii…a new arrival in our district: how did it get here?

A grisly list of the problems associated with this plant can be found here. They relate to the seed, a diabolical looking object vaguely like a land mine from an alien planet. It’s painful to stand on, punctures bike tyres and can stick to pets’ feet. Obviously not something to have to put up with on a sports field.

Caltrop seed: a glance will suggest why it’s painful.

Caltrop/Bindii is most commonly found in the North of Victoria, but seems to have recently arrived in Castlemaine, where it’s been found on the Western Oval and some roadsides. How did it get here? The common factor in all sites found so far is that they’ve been disturbed by road and other works, or seem to have soil brought in from elsewhere: another reason for paying more attention to the cleaning of machines, and for being more careful about transferring soil from one place to another.

The terms of reference for the national royal commission into bushfires contain some potentially fruitful lines of enquiry, including the ideas of national policy on biodiversity, land use planning, and indigenous land use practices.

One of the challenges the commission will face is the directive to take into consideration ‘other reports and enquiries’. There have been more than 50 of these, and it’s hard to see how the commissioners can come up with something new, unless it’s a way of actually getting recommendations effectively implemented.

Take land use planning, for example. Here’s part of the Black Saturday Royal Commission recommendation 39 on the matter: ‘The State amend the Victoria Planning Provisions relating to bushfire to ensure that the provisions give priority to the protection of human life, adopt a clear objective of substantially restricting development in the areas of highest bushfire risk—giving due consideration to biodiversity conservation—and provide clear guidance for decision makers.’ [FOBIF emphasis].

Here’s Kevin Tolhurst on the fate of that recommendation:

‘The Government and its agencies has … been timid in applying land-use planning regulations in bushfire-prone areas. While the CFA, with its experienced and specialist bushfire planning staff, has been removed from its role as a planning authority with the power to accept or reject planning applications for buildings and developments in bushfire-prone areas.’

Let’s see how this Royal Commission goes around that circle.

Another part of the terms of reference is to investigate the matter of ‘hazard reduction.’ Although this has been a favourite theme of commentators wanting to distract the public from the fact that climate change might be making bushfires worse, it also could be a good subject to consider.

Except that it too is an idea that’s been kicked around endlessly with no apparent consensus. Who now remembers the 2008 Victorian Parliamentary enquiry into land management and bushfires? One of its recommendations was a huge burn off target. The State Government said of that recommendation:

‘The Victorian Government supports planned burning to improve protection, conservation and production outcomes. However, the annual area treated by planned burning needs to be determined based on science and risk management frameworks and be subject to  opportunities as dictated by seasonal conditions.

‘Given this, the Government recognises that the amount of planned burning will vary to take into account these factors.

‘The Government supports a move away from focusing on hectare—based targets which may lead to inappropriate planned burning outcomes. They do not account for differences in the effort required for small area asset protection burns (often around settlements) compared to larger scale mosaic burns in more remote areas.

Then, only a few years later, the Black Saturday Royal Commission recommended a rolling 5 per cent target…and it was found unworkable and ineffective by the Commission monitor, for exactly the reasons set out in 2008—but only after a large area of land had been burned for no sensible reason.

Let’s hope we don’t have to go around that circle again.