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Comment by bouncycastle | Hacker News Reader

The problem has probably been compounded by the fact that previous bushfires have always been actively fought and many were extinguished, thus allowing more combustible material to build up over decades, where without man's intervention, the bush would have burned in its natural lifecycle.

A lot of the plant material in Australia has evolved around fire. Take for example paper-bark trees which developed a fire resistant shell around their trunks. The blue gum trees especially thrive after files https://www.google.com/amp/s/www.livescience.com/amp/40583-a...

BTW, I've witnessed an Australian bushfire up close once (standing safely at a beach). These gum trees really do explode as the descriptions say, its an incredibly ferocious fire. Perhaps that's their evolutionary trick - burn everything out around them so that their seeds will have less competition to thrive for the next generation.

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California, being a paragon of long-term planning, decided to import the pyrotechnic eucalyptus to the state, thinking it would be a good source of fast-growing lumber of railroad ties.

Welp, turns out eucalyptus makes terrible lumber, is unsuitable for railroad ties, lowers the water table, poisons the native flora, and can spontaneously ignite when sunlight shines on drops of the resin.

Oops!

Eucalyptus are also known to explode when set on fire. Another Australian flora/fauna that will actively try and kill people.

In my area the eucalyptus was primarily used to create wind breaks and and shaded areas in otherwise wide open barren landscapes. I think maybe there were multiple uses, but agriculture / soil-erosion and sun protection were definitely one of the early ones.

Some species of Eucalyptus I've heard need fire for their seeds to "activate"/germinate. They've also discovered a huge variety of Australian plants in valley's where the fire never reaches (think the Wollemi Pine); where everywhere else is really just eucalyptus. If fire could eventually start in an area you pretty much just have eucalyptus bush everywhere and nothing else.

My non-educated hypotheses is that eucalyptus was a very dangerous weed that uses fire to basically kill everything else around it. It managed to kill via fire every other native Australian plant in the bush expect with the exception of some safe sanctuary spots (close to water, deep valley's where moisture content is higher) many years ago. Some other plants have evolved against this and adapted to fire however (think Australian grass trees).

They did the same thing in Israel. It's PACKED with Eucalyptus trees. They say it was important to "drain swamps and fight malaria", but since then it has spread literally everywhere.

I'm surprised by this mistake because it's rather obvious and I'm not even a botanist.

That's too bad, as eucalyptus trees are some of my favorite, with plenty found in East Bay parks :(

I'm partial to sequoias too, except for the mess they make in the yard.

If you ever get a chance to visit the arboretum at UCLA, they have a lot of labelled eucalyptus trees.

> Perhaps that's their evolutionary trick - burn everything out around them so that their seeds will have less competition to thrive for the next generation.

There's likely some truth to this. Much vegetation in Australia has adapted to regular burning due to relatively frequent natural fires and "fire stick farming" practiced by the indigenous population.

For instance see Xanthorrhoea australis [1] which flowers prolifically after a bushfire to take advantage of reduced competition.

[1] https://en.wikipedia.org/wiki/Xanthorrhoea_australis

Keep in mind this doesn't really apply to rainforests which were much more widespread before the arrival of humans (both white and native). Rainforests take a long time to build up and are resistant to fire through their damp and cooler nature. But once they're gone the gums move in.

We once went hiking in a newly opened area close to Mt. Kosciuszko, which had previously been decimated by fire. The new growth was so thick and high, it took us 6 hours to walk 5km (3mi), all the while hunting for the pink tags left by the rangers that showed the "path".

It is certainly not that far-fetched to see how the plant life Down Under has evolved to live with and take advantage of wild fires...

I guess we’ll see in future fire seasons if that’s been a significant contributor. If so, they should be less severe.

It does seem like a ruthless ecology. Eucalyptus will kill everything around them via toxic droppings too.

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