The Royal Commission into the Black Saturday fires will table its preliminary report to the Victorian Parliament today but issues of fire management and the organisational response to the fires could overshadow how the fires started and what exactly burned.

All the fires on February 7 2009 were lit or caused by people — no fires were started by lightning or any other natural causes. There were dozens of fires that were deliberately lit across the state, most of which were small and put out by the CFA.

The current Royal Commission has not yet looked at the causes of the fires but powerlines have been implicated in some fires and there is now a class action against power company SP Ausnet.

A major portion of the Ash Wednesday fires in 1983 were started by powerlines, slackened by hot weather, which clashed onto trees and sparked — starting the fires. In response, after being successfully sued, the then State Electricity Company cleared powerline reserves and improved maintenance — especially in coastal areas where an accumulation of salt on insulators can “short” and start fires. Whether or not this level of maintenance has been maintained with the breakup and privatisation of power industry is not known.

Also, the Royal Commission has not yet published any examination into the vegetation types that ignited on that day, or research on how fast the fires moved through farmland and various types of bush.

Where the fire fronts — sometimes kilometres long — hit old forests it appears that the burning was stopped or slowed down. It is possible that in the older, wetter forests the wood, bark and leaf litter which rots and holds water remains cooler as it increases with age. This would make it a lot harder to burn and would explain the apparent edge where the fire fronts hit the older forests. The evidence will be there along the boundaries of the Black Saturday fires.

It’s also likely that the introduced species of pasture grasses that die off, ungrazed, in the summer time along road reserves present a greater fire hazard that the bush which has been or is being planned to be cleared. And in many places burned there are now vast expanses of bracken which is among the most flammable plants in the bush.

Many people in the community, particularly those in the Victorian towns most affected by the fires, have turned against “the bush”. Academics and politicians have hit the media hard, blaming the lack of fuel reduction burning and even the clearing of trees.

In the absence of research, unburned and barely burned forests of ancient trees have been cleared from in and around bushfire affected towns. This has caused additional stress to many people who moved to these areas to live in the bush. It may also be counter productive.

Hopefully the answers to these basic questions will be available today from the Royal Commission’s interim report.