Wildfires: “a significant oversight”

By Richard North - August 14, 2023

After the passage of days, we’ve seeing some more considered analytical articles on the Maui fire disaster.

Up front is the Washington Post which offers a piece headed: “Why Hawaii’s wildfires are so devastating – and ‘predictable’”, with a sub-heading telling us that: “The ecological ravages of Hawaii have left behind non-native grasses that serve as fuel for blazes. Some experts say the islands have yet to fully prepare”.

Following on a few days later is the Sunday Times, an article from which has scientists explaining “the key factors that led to the catastrophe”. It refers to the “tinder-dry conditions” which, it says, were more dangerous “because of the spread of tropical non-native grasses, such as guinea grass, that had grown to occupy about one million acres across the state”.

These grasses, the paper says, are highly flammable. They accumulate biomass such as wood residue during the wet periods, creating dangerous conditions for firefighters.

A scientist we met in my earlier blogpost, Clay Trauernicht, is quoted extensively, saying amongst other things that he has been flagging the dangers of invasive grass to fire response agencies for years.

“The bottom line”, he says, “is that the change in land use in the past several decades, namely the decline in large-scale agricultural and ranching operations, has resulted in thousands of acres of unmanaged fallow lands”.

Interestingly, we also hear from Stefan Doerr, director of the Centre for Wildfire Research at Swansea, who says that the replacement of arable land with grass has been one of the key reasons that this summer’s fires on the Greek islands of Rhodes and Corfu were also severe.

Then we have the Observer, writing about the “growing threat of ‘devastating’ fires as island landscape dries and warms”, with the text telling us:

Long before fast-moving flames descended on the historic town of Lahaina, the growing threats of catastrophic fire in western Maui were clear. Acres of abandoned farmland that line the picturesque coastal communities played perfect host to invasive grasses that are primed to burn, creating tinderbox conditions as the island’s landscapes dried and warmed.

Common to the narrative in all three pieces, therefore, is the central role of the non-native Guinea grass, displacing to a certain extent the rhetoric about climate change. Yet, even these articles do not begin to convey the scale of the peril to which the town of Lahaina on the western side of the island was exposed on Tuesday 8th August, when the town was all but destroyed.

With an uncanny degree of prescience, however, a mere two days before the destructive fire in Lahaina, the journal Science published on-line an article headed “Fiery invasions”, warning that: “Around the world, flammable invasive grasses are increasing the risks of damaging wildfires”. Putting the problem into context, the article tells us:

Even as catastrophic wildfires that roar through towering treetops capture the public’s attention, ecologists have been paying increasing attention to this less conspicuous trend: how seemingly modest nonnative grasses are allying with fire to eat away at dry forest and savanna ecosystems.

These invasive grasses can hijack fire to create a self-reinforcing cycle, explains Carla D’Antonio, an ecologist at the University of California, Santa Barbara, who has studied the phenomenon for more than 3 decades in Hawaii and California. Once established, the grasses help fuel blazes that kill and suppress less fire-tolerant native plants, opening up new territory for the invaders to colonize—catalysing yet more fire. In a short time, land that was once shrubland, savanna, or dry forest is locked into being a grassland. “It’s that trigger of grass and fire that sets the system off in some undesirable direction,” D’Antonio says.

This is the big eye-opener. Although we tend to associate wildfires with forest fires, and carry images of forests and burning trees, in many respects, grass fires driven by non-native species, are far more deadly. Not least, as a PhD study pointed out, predicted fire behaviour was more extreme in grasslands than in forests, with rates of spread 3-5 faster and flame lengths 2-3 times higher in grasslands than in forests.

Furthermore, in respect of the Guinea grass infesting the Hawaii Islands, because of the nature of the growth cycle, dead fuel loads were consistently high, making up at least half, and often closer to 75 percent, of the total fine fuel load in these grasslands. This makes the grassland easier to ignite and more likely to combust even when moisture levels are relatively high.

Looking through a huge body of work, it is clear that this problem is well known – in academic circles at least – and by no means confined to Hawaii, with Texas researchers describing Guinea grass as a wolf in sheep’s clothing – one of the worst invasives in South Texas, spreading into Central Texas at an alarming rate.

If the academics were and are aware of the threat, though, the message does not seem to have percolated to the local government in Maui – if the 2021 official report on wildfire prevention is any guide.

Written in the wake of Maui’s “unprecedented wildfire season in 2019”, where more than 20,000 acres were burned and resources seemingly stretched thin, the
the Cost of Government Commission decided to examine the County’s wildfire prevention and response practices and costs.

The Commission was interested in identifying the current and potential future costs associated with firefighting response and prevention for the County, as well as what additional policies or actions might be needed to reduce these costs and losses.

The investigation conceded that the number of incidents appeared to be increasing, and that this increase posed “an increased threat to citizens, properties, and sacred sites”.

At the start of the inquiry, it was assumed that an increase in fire events would subsequently increase firefighting cost overruns, response problems, and result in budgetary pressures for additional fire prevention and fire response resources. However, says the report, “this assumption was not supported by the research”.

It was also assumed that new regulations would likely be needed to meet wildfire threats. This assumption was also not supported. Furthermore, the investigation revealed that current budgets, combined with County and State access to Federal emergency relief funding, were adequate to meet the current fire threat, but it was conceded that they were “inadequate for an effective fire prevention and mitigation programme”.

When it came to fire prevention though, the Maui County Department of Fire and Safety had then recently released its strategic plan for 2021–2025, whence prevention was “given short shrift”. This was despite Professor Trauernicht’s wisdom. He had told the inquiry:

You’ve got this sort of one-two punch when it comes to wildfire season in Hawaii. It’s not only drought. Coming out of a wet winter like we’ve had, you’ve got a lot of vegetation and particularly grasses that have done nothing but grow and grow and grow very fast. But they go from green to yellow to brown pretty quickly and that is making us way more vulnerable to these big, destructive fires.

Yet there was no stated goal for fire prevention, nor any metric to assess success or improvement in prevention. There was much space devoted to preventing injuries and illness in employees, and to preventing equipment failure, but nothing about what could and should be done to prevent fires.

Thus, the Commission found that existing preventative and enforcement practices of the Maui County Fire Chief could be expanded to achieve needed wildfire prevention and safety measures pursuant to State law – without setting out any specific measures, content with noting that The [Fire] Department’s new strategic plan had failed to address fire prevention as a mission or goal. It called this “a significant oversight”.

As to what prevention measures could and should be taken, this is a complex subject and will provide material for another blogpost. But, while there are still those who wilfully prattle about the effects of climate change, the destruction of Lahaina begins to take on the mantle of government incompetence and an extraordinary level of complacency, all in the face of a known and quantifiable threat – which wasn’t climate change.

One wonders to what extent the climate change rhetoric excused or legitimised the lack of action, in the certain expectation that no number of electric cars or heat pumps would have made any difference. One should also note that, as of 2017, Hawaii had the highest share of petroleum use in the United States, with about 62 percent of electricity coming from oil.