Reasons to be cheerful: botanist Peter Latz on our deserts

For eighty years, botanist and author Peter Latz has been watching the world change from his back yard, through the prism of his beloved arid zone plants and their ecosystems.

It’s a split-level back yard. At the macro level, we’re talking about pretty much the entirety of Central Australia, an area the size of France, as he likes to put it. At the micro level, it’s a twenty acre block on Roe Creek, 15 km from the town of Alice Springs. Here Latz made his home nearly 40 years ago, and has been able to observe and experience changes at close range through all the variety of conditions the Centre undergoes: flood, drought, fire — and all the peaceful times in between.

His verdict on this ever-changing world may surprise you: We’ve never had it so good!

While the public conversation is dominated by predictions of doom for humans and other animals and danger for the planet, Latz is looking at his world as it actually is, and how it’s changed since he was a boy growing up Hermannsburg in the 1940s.

Well-known for his research into the long back story of humans and plants in the Centre — and what may have come before the humans — the author of Bushfires and Bush Tucker believes the country may not have looked this good for “thousands of years”.

 I sat down with Peter at his block

. What follows is PART ONE of an abbreviated transcript of our conversation — starting with the bad news.

Peter: For the world as a whole unless we change our ways, global warming is really going to stuff up the planet, but the interesting thing is that living here in Central Australia we’re actually better off at the moment — I don’t know about the future — with global warming. The plants at least — and that’s the thing I’m most interested in.

Dave: How can that be?

For a start, desert plants’ biggest limiting factor is water. In the desert when you have more carbon dioxide in the air you have to open your stomates for shorter time to let the carbon dioxide in, and that means you lose less water from evaporation. So in other words, in Central Australia now, and in most of the deserts of the world, plants are favoured by carbon dioxide. It doesn’t work so well for wetter areas, because the limiting factor in wet areas is nutrients, if you’ve got plenty of water. And so extra carbon dioxide doesn’t help you.

Is this something you’ve observed?

Oh yeah. See, in my nearly 80 years, the other important thing is about every 25 years we used to have really bad droughts, and I mean bad droughts. I remember trying to walk home from town one day in Alice Springs and the only way I could find my home was to follow the road because I couldn’t see from here to you for dust. Now we haven’t had one of those for 50 years, so in other words, every 25 years we used to have terrible droughts and now we haven’t had one for 50 years.

We’ve had a couple of very dry years, though, haven’t we?

Yeah, and what’s happened — if you look over there — you can see lovely wattles looking very healthy after the worst drought we’ve had in the last 50 years. In the past, every 25 years, every wattle died— flowered and fruited, produced some seed in the ground, then they all died, every single one of them. Now I haven’t noticed this at all in our last drought.

It’s still quite a short time, to talk about — 50 years — when we’ve got so little knowledge.

Plants have to put up with extra temperature but they’re used to that. Up till now I’ve never seen the country so good. I reckon there’s nearly twice as much biomass in trees and shrubs in Central Australia now as when I was a kid.

Now we have to blame the rabbits, as well, and so it’s not just global warming.

The rabbits having gone, things are coming back?

Yes, they used to ringbark a lot of the trees and shrubs. We’ve still got rabbits, but they’re not a serious menace anymore. So yeah, the plants in the last 50 years are the best they’ve ever been, probably the best they’ve been for thousands of years.

Wow! But, given that and given that you also expressed concern about the planet in general, what should we do, knowing that it’s good for us (here) and it’s good for deserts but it’s not necessarily good all round?

Well, we don’t know what the future still holds. I mean, some of the scientists say that we’re gonna have worse droughts, and bigger floods as well, but that doesn’t seem to have happened here, and of course we don’t have to worry about sea level rise in Central Australia! But yeah, we really have to pull our finger out and do something about the extra carbon dioxide in the air.

You know, the plants were doing OK before the extra carbon dioxide. They’re better off at the moment but who knows what’s going to happen in the future? I’m an optimist. But humans are well-known for waiting until the last minute … we’ve definitely got to pull our finger out. But you know, the other exciting thing is, China and India are the world experts on getting sustainable energy.

But they’re still using the most fossil fuels.

Well, we could not have got to where we are without the use of fossil fuels … especially, places like Africa have got to keep using them until they get enough money or economy to be able to produce (alternatives).

Are you worried about how hot it might get?

Well, as I said, our plants are pretty much adapted to the heat so it’s the humans that are going to suffer more than the plants. I’m not saying that we aren’t in trouble all over the world, that’s for sure. I’m just surprised.  And the other problem with global warming for here is that you get more growth, that means more bushfires, and the heat helps that as well. So we really need to not only pull our finger out with sustainable energy, but we need to work on preventing bad fires.

It’s quite a complicated story, because inevitably there are going to be wins and losses, and winners and losers. Some crops that will grow better, particularly in the northern hemisphere and maybe winters that aren’t quite as savage. How do you feel about children growing up… the Greta Thunbergs… with this kind of despair, that there is no tomorrow?They seem to think they are living in the final days and the planet is doomed.

But isn’t that a great thing, that the kids are worried about it? I’m not saying they haven’t got reason because you know, we’ve buggered things up for them and we’re expecting them to pull us out of it, but at least the young people, being better educated and so on — we wouldn’t have got here, we wouldn’t have been able to educate all our children if we hadn’t had coal and gas energy.

You can’t say it’s all bad, and I don’t think there’s any doubt that we have only obtained …. I mean, we’re living in the best time of the Earth ever! You and I have been so lucky to have grown up at this time in the planet’s history, because there’s now fewer hungry people on the Earth, less war. Really, the world is the best it’s ever been.

Dave Richards.

Watch for the second part of this interview, in which Peter explains why he is optimistic about the on-going survival of the unique trees, shrubs and grasses of the arid zone — and how the threat of invasive species like buffel and couch grass is being checked. You can also watch the first of a series of  Youtube videos of the interview.