This was written by Maurie Killeen in July 2018.
Our Australian forests are different now than say 50 years ago and again different than 300 years ago and with the current practice they will be very different over the next 30 years.
Before Europeans, the indigenous had a management system for forest and grasslands that was pleasing to a different set of European eyes.
There are suggestions this system was developed over many years after the mini ice age, it is said Australia became covered in tropical jungle and was slowly transformed to the forest and grasslands the first Europeans saw.
Some suggest it was another race of people migrating from the north with the fire stick when the sea was much lower from the remnants of the mini ice age or it was part of a long term climate shift with violent storms, cyclones and lightning that flattened the jungle and when dried out was lit by lightning.
In parts of arid Australia there are steep gorges still with tropical vegetation in them.
There has been mention of 1770 as a benchmark for tree and forest cover.
There is also mention pre 1770 Australia was coming out of a 100 year extreme drought experience.
After 1800 with decline of the aboriginal burning regimes from most of Australia the forest closed in with scrubby understory, open plains grew more trees with scrub and by the 1850s Australia’s forested area could well have doubled.
And the so called 1770 benchmark probably was taken from the 1850 forest cover.
Victoria’s first recorded big bushfire was in 1851.
This puts the age old Green quote “two thirds of Australia’s forests have been cleared” in a different light.
Fire Prevention and Fire Management
Regardless whatever the history was, management of a many small parts of Australia was starting to change again from about the 1830s when settlers got into and over the ranges with different livestock.
Most of the cleared or parklike areas the settlers quickly took up early and the fire management practices were maintained by the new occupants , but in the vast areas of forest in between these areas some were left to the whim of the elements as there were less or no indigenous left to continue the management.
In other fertile places in the world the upset of vegetation management was not an issue, but most of Australian soils and some vegetation are very old and fragile and the whole vegetation system along with the inhabitants was always on a knife edge for survival and was tipped over.
If the plan was to get this management system back again using indigenous workforce and knowledge it would take many years, and it has been 5 to 10 indigenous generations gone by the way and very little of this knowledge handed down especially in the southern parts, and those indigenous who would deliver the management would need to be taught as it is not a skill you are born with.
With the current government thinking and rigid rules and regulations, past indigenous management would not be possible.
We need to work hard to have the strict government guidelines and impediments changed to start a revised fire prevention and mitigation system to enhance and rejuvenate the forests.
Indigenous fire management varied greatly across Australia, the far north of Cairns to Cape York and across Arnhem Land and the Kimberleys was a lot different to say Victoria and southern NSW, and there were many differences again within these areas.
Today there are differing opinions of fire management on around Cooktown and Cape York and the eco system has been changed in a very short time.
Harvesting the Forests
Up until the 1960s the harvesting of forests was selective harvested for sawlogs where the larger logs were taken and the smaller ones left to grow and 20 to 50 years later the forest was ready to be selectively harvested again.
Power and telegraph poles did take some small trees that could have grown the sawlogs but this was not a real threat as only a small few in a forest patch were suitable to take as a pole.
The taking of the Red Cedar was one area we could have done much better.
When the harvesting of whole logs for export woodchips started in the 1960s only the old hollow logs not suitable for sawlogs and the tops of sawlogs were utilised for woodchips, then the woodchip exporters wanted whiter chips from smaller young trees and clearfell came to being the normal .
This had a big impact on sawlog supply and fire management.
Fire management in a selective logged forest was not much different to a virgin forest, but a clearfell forest grows as a plantation for a long time and it is harder to fire manage without destroying the forest.
Now there are a lot of these native “plantations” amongst our forests at different stages of growth.
Getting our forests back to a stage to re-introduce indigenous burning regime.
Our forests have become a mix of fire treatment ranging from extreme wild fire, wild fire, moderate wildfire and hot moderate and cool fuel and eco burns as well as no fire treatment.
First we have to stop burning large areas and classing them as eco and fuel reduction burns because they generally become controlled damaging bushfires.
Large hot fires whether they are wildfires or “managed” fuel reduction fires promote accelerated growth for more frequent fires.
The indigenous managed tall tree forest had a closed canopy and low vegetation bushes of one metre or less in height on the forest floor, forming two levels of leaf matter.
The aim was not to have crown fires as it would let the direct sunlight in, strike the seeds and a new forest of eucalypts would shoot up and grow, then the canopy would finally restore and grow over blocking the direct sunlight leaving this mass of new forest with nowhere to go.
The new forest becomes stunted and bushy forming a third layer of high loads of leaf matter.
The forest then has high concentration of dry leaf matter on the forest floor from the previous burnt crown and now the middle layer which can be more than four times the fuel load of the original forest dropping leaves and woody fuel.
This third layer make a violent stepping stone to activate a crown fire from a docile fire on a mild day, resulting in most bushfires and prescribed burns in the last 30 years ending up as part or all crown fires.
There is need to have more one or two vehicle width tracks kept open to have many small patches to burn out within a day, this way a fuel reduction burn is not given a chance to build up.
The prescription for these small burns would need to be revised to have clearance to be lit whenever the hour suits.
After a concerted effort for say 10 years a mosaic of lots of cool burned small patches is created.
Then we are ready to operate as the indigenous burns were managed and some of those lightning strikes could be let to burn out.
Also the thrill of a statement by arsonists would diminish.
Also in some areas after a few cool burns are carried out it should get to the stage the vegetation will slow its growth considerably and very little or any burning would not be needed for a long time.
Regards the alpine forests there was a view that the indigenous managers didn’t burn them but burnt the lower forest that was a buffer to protect the alpine forest.
But as the Ash forest doesn’t need much of a bushfire to be killed, it was probably wiped out and started over again.
Maurie Killeen. 24/7/2018