Backyard gardeners around the world are helping to save Australia’s deeply ancient Wollemi pine


Heidi Zimmer, Southern Cross University and Catherine Offord

As bushfires blackened forests last summer, one tree species was protected by a specialist team of firefighters: the Wollemi pine.

These trees have a deeply ancient lineage dating back to when dinosaurs walked Gondwana 100 million years ago. Back then, rainforests – including Wollemi pines (or their cousins) – covered what became Australia.

So when a handful of Wollemi pines were discovered alive in 1994 on the brink of extinction, it caused a frenzy of interest that has barely died down among plant enthusiasts.

How firefighters saved the Wollemi pine from the bushfires.

Today, fewer than 100 mature pines are left in the wild. But their exact location is one of the best kept secrets in Australian plant conservation, to protect them from pathogens such as the root-rotting phytophthora that might hitch a ride on human visitors.

But while rare in nature, our ongoing research with citizen scientists is finding Wollemi pines grow in backyards all over the world, in a range of environments, and this information can inform how we can protect them in the wild.

From Gondwana to the garden

The Wollemi pine is considered the iconic poster-child for plant conservation. It’s an unusual-looking plant – each wild tree has many trunks covered in bark resembling bubbling chocolate and branches of lime or grey-green fern-like leaves. And in the wild, they grow to more than 40 metres tall.

The species is a member of the southern conifer family Araucariaceae, and its cousins include the monkey puzzle tree and the Norfolk Island pine. While considered a rainforest tree, many remaining in the wild exist between rainforest and dry eucalypt woodland, on the ledges of a sandstone gorge.

Wollemi pines can stretch 40 metres in the wild.
Heidi Zimmer.

Since the Wollemi pine was discovered 26 years ago, the protection effort has been intense, focusing on conservation in the wild.

One of the first strategies was cultivation. Horticultural scientists at the Australian Botanic Garden Mount Annan (Sydney) worked out how to propagate the species so it could be grown and enjoyed in gardens, reducing the risk of illegal visitation in the wild.




Read more:
Wollemi pines are dinosaur trees


After the Australian Botanic Garden established a basic “insurance population” of plants propagated from the wild trees, some of the first cultivated Wollemi pines were distributed to botanic gardens in Australia and overseas, including in the UK’s Royal Botanic Gardens Kew.

In 2005, Wollemi pines were auctioned to the public at a Sothebys Auction. Since then, they’ve been exported to many nurseries around the world, and now grow in many public and private gardens.

I spy a Wollemi pine

When plants are very rare in the wild, or are very restricted in their distributions, conservation away from the site (ex situ) can play an important role in their survival.

This includes seed banking, translocation (establishing new populations of rare plants in new locations) and cultivation for the nursery trade.




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Where the old things are: Australia’s most ancient trees


Enter our I Spy A Wollemi Pine project. Fifteen years after the Wollemi pine became available for sale, our study asks people to report where Wollemi pines are growing in gardens across the world.

So far, results from the online survey have revealed the species grows across 27 different countries, from Australia to Russia, and the UK to Peru.

The tallest trees so far – stretching to 7 metres tall (though dwarfed by their wild counterparts) – have been reported from the UK. To date, 987 people have contributed data about Wollemi pines.

Wollemi pines growing in Coates Wood, United Kingdom.
Ellen McHale © RBG Kew.

What we can learn

Reading comments from survey participants – from “Has survived minus 10 degrees” to “I just love it” – has been a source of interest and joy for us researchers.

When the survey is finished, we’ll analyse the responses to understand what influences the growth of this species, such as different climates and soils.

Knowing how Wollemi pines grow in other parts of the world will provide gardening tips for home growers, but more importantly it will inform future conservation efforts in the wild in the face of climate change.




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For example, this research will provide information on what environments the Wollemi pine can tolerate. We’re discovering the hottest, coldest, wettest and driest places on earth this species can survive in.

This information can help us find places to establish new populations of Wollemi pines. It may also provide clues on the evolutionary history of this species and how it managed to survive multiple ice ages and other dramatic climate changes in deep history.

Conservation with cultivation

Conserving Wollemi pines in backyards is not quite the same as Wollemi pines in the wild – in the same way its important to have pandas in the wild, and not just in zoos. But using cultivation for conservation does mean these species have much greater distribution today than they have ever had in the past.

In fact, this isn’t the first time a rare tree has ended up in gardens. The dawn redwood, thought to be extinct in the wild, was rediscovered in China in the 1940s and can now be found in gardens across the world.

And the internet is a great place to foster conservation. In online forums, people share every stage of their Wollemi babies’ growth, from seed germination to pine cone production.




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This love and connection to Wollemi pines might even help address “plant blindness”: the propensity for people to see, recognise and focus on animals rather than plants, despite plants being central to providing us with food, the air we breathe and our climate.

So, as more species are threatened with extinction every day, everyone’s actions – even in their own backyards or online – can make a difference.


If you have a Wollemi pine in your backyard, or know of a Wollemi pine in a park or garden, and would like to get involved in our citizen science survey, please click here.The Conversation

Heidi Zimmer, Research associate, Southern Cross University and Catherine Offord, Senior Principal Research Scientist

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Climate explained: could the world stop using fossil fuels today?



Dave Greenberg/Shutterstock

Ralph Sims, Massey University


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Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

If we stopped oil, gas and coal extraction immediately – what would happen? What would we need to change about the way our economies and societies work in order to adjust to that resource no longer being available? Do alternatives already exist that mean it could be business as usual if we (governments and individuals) make changes, or would it mean a major adjustment to the way we live our lives?

It is not feasible to immediately stop extracting and using fossil fuels. The global economy, human health and livelihoods currently depend heavily on oil, coal and gas. But over time, we need to displace fossil fuels with low-carbon renewable energy sources.

The first priority should be on switching to renewable energy, not just for electricity but also for heating, cooling and transport fuels. It will be much harder to substitute fossils fuels used for chemical processing, such as the manufacture of plastics or fertiliser, but it is technically possible with biomass (organic material from plants and animals). After all, the hydrocarbons in coal, oil and gas were originally derived from biomass millions of years ago.

The aim of governments, local and national, should be to encourage reduced use of fossil fuels by supporting renewable energy systems.




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Increasing contribution from renewables

One issue is that global subsidies for fossil fuel extraction remain large, at around US$4.7 trillion per year according to the International Monetary Fund.

In a recent global energy review, the International Energy Agency described a significant drop in energy demand from fossil fuels as a result of the COVID-19 pandemic. Demand is likely to rise again, but in the meantime, the use of renewable electricity continues to increase and now has a 25% share of global electricity.

Countries with good renewable resources can reach a significantly higher share. New Zealand, for example, now produces around 85% of its total electricity from renewable sources (including hydro, wind, solar and geothermal) without government intervention. But overall, renewable energy contributes only 40% of all energy demands in New Zealand, and far less globally.

There are many examples of how renewable energy can meet intensive industry demands, in New Zealand and elsewhere. New Zealand’s aluminium smelter uses electricity generated by the country’s largest hydro power station built underground at Lake Manapōuri. A steel mill in Sweden uses “green hydrogen”, produced by using renewable electricity to split water into hydrogen and oxygen.

The Manapōuri hydro power station supplies electricity to New Zealand’s aluminium smelter.
Uwe Aranas/Shutterstock

Green hydrogen can also be used to displace natural gas for heating and cooking as well as for fuelling trucks, cars, boats and planes.




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Immediate phase out of fossil fuels could keep warming below 1.5°C


The costs and benefits of change

There are many alternatives to fossil fuels with far lower carbon footprints. This includes electricity generated by nuclear power plants.

But the problem is fossil fuels remain relatively cheap, because the cost of their pollution isn’t usually factored in, and energy dense (there is more energy contained in a lump of coal than a piece of wood of a similar size). Displacement is not easy and will take time to allow those working in the fossil fuel industry to go through a “just transition” to work in other sectors.

Government intervention is often required for low-carbon options to increase their share in meeting total energy demands. But changing people’s behaviour around energy use is more challenging than deploying new low-carbon technologies to provide the same energy services.




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We should not forget the additional benefits that come with a shift to low-carbon energy generation. More walking and cycling improves health, electric vehicles reduce local air pollution (compared with petrol and diesel vehicles) and using public transport and carrying more freight by rail can reduce traffic congestion. Other simple energy-saving measures – switching off lights, not wasting food – can all save money while lowering someone’s carbon footprint.

We have become a wasteful society, with consequences for the environment. Perhaps now is the time to make major adjustments to how we live before climate change impacts do it for us.The Conversation

Ralph Sims, Professor, School of Engineering and Advanced Technology, Massey University

This article is republished from The Conversation under a Creative Commons license. Read the original article.