ELEANOR HALL: While some politicians say now isn't the time to talk about what is driving these extreme fire conditions – especially if it involves talking about climate change – some National Party politicians do want to talk about backburning.

So has there been enough hazard reduction burning going on?

And, if not, why not?

Isobel Roe has more.

ISOBEL ROE: Bronwyn Petrie knows the Tenterfield region in northern New South Wales well. Her family has been on the land for five generations and in recent years she's seen an increase in the frequency of bushfires.

As she spoke to me she describes a nearby fire, ablaze in the tops of the trees around 25 kilometres away.

BRONWYN PETRIE: It just spreads so rapidly and it kills every living thing in the heads of those trees that have gone up there to escape.

All the little nesting birds at the moment, the koalas, the gliders, the lizards: you name it, they're up in there being incinerated.

ISOBEL ROE: And in the past couple of years the bushfire threat has increased. She attributes this to local authorities not burning off as much.

BRONWYN PETRIE: Up until two years ago there's no sign of a crown fire on our 25,000 acres, no sign at all. But in the last two years it has happened because fuel loads have intensified.

ISOBEL ROE: She blames gradual policy change and pressure from environmental groups for the increase in fuel loads.

BRONWYN PETRIE: Over the last 15 or so years there's been a change in the rules. The hazard reduction burns or agricultural burns you can do: you have to have a hard edge, or else you can't have a permit.

So that means you need to have a road. You need to have a fence line or something where you contain the fire in.

The thing is: they say, "Oh, we will not have running fire." But the fact is: as a result of this, there's a lot of country – simply, it's impossible to have a hard edge because of the nature of the terrain.

ISOBEL ROE: And who made the rule saying that you had to do it like that?

BRONWYN PETRIE: Well, the Rural Fire Service makes the rules; state agencies, whether that's forestry corporations or national parks or local land services.

ISOBEL ROE: The National Party says the Greens Party have made it more difficult to light fires.

But that's a claim rejected by fire risk management expert, Professor Ross Bradstock:

ROSS BRADSTOCK: The notion that there is some sort of conspiracy to stop hazard reduction is a piece of fiction.

ISOBEL ROE: He says there's more pre-burning happening in New South Wales than ever, but state agencies don't have the money to do the amount of burning needed to prevent fires like those in the state this week.

ROSS BRADSTOCK: Hazard reduction will only put a dent in risk. It will not eliminate risk, because the amount of hazard reduction you would have to do to eliminate risk is beyond the financial resources of the state.

ISOBEL ROE: Professor David Bowman works in pyrogeography, the study of wildfire, at the University of Tasmania.

ROSS BRADSTOCK: What we're really talking about here is the tension between a command-and-control and regulating the use of fire in the landscape and a more organic, self-organising use of fire: 'the old school' way of doing it.

ISOBEL ROE: And he says, as the population grows in semi-rural areas, the harder it is to light safe fires.

ROSS BRADSTOCK: And they're becoming increasingly complicated because of the effect of shrinking safe weather windows and increased intensity of the fires.

But as you come down into the settled areas, the complexity of planned burning increases. As you get more land tenures, you have to have more sign-off, more regulation, more agreement.

ISOBEL ROE: Professor Bowman believes the budget for hazard reduction burning needs to dramatically increase, not just to increase burning but to develop better ways of doing it.

ELEANOR HALL: Isobel Roe reporting.