The fagus turns… but for how long?

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As thousands flock to witness Tasmania’s annual ‘turning of the fagus’, we wonder how much longer could it last?

By Liz Ginis

April 19, 2022

Reading time: 2 Minutes
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Australia’s only cold-climate deciduous tree is spinning.

Its leaves are blushing brilliant autumnal yellows and oranges at this time and by mid-May its branches will be mostly bare. The rare Tasmanian Nothofagus gunnii (fagus) is a stunning reminder of Australia’s Gondwana heritage. This small tree, usually less than 2m tall, is quite unique to the mountains of Tasmania.

It grows in stands in the remote mountainous regions of the Tasmanian Wilderness World Heritage Area, covering a total area of ​​less than 11,000 ha; it requires cold winters and more than 1800 mm of rain per year. The annual “turning of the fagus” that attracts hikers from all over to enjoy the spectacle is a fiery reminder that Tasmania was once part of the southern supercontinent of Gondwana.

Related: Turning the fagus

The fagus is considered by scientists to be a key to understanding the evolution of vegetation in the southern hemisphere.

“They have a fabulous story to tell us, not only about the history of Tasmania, but also about the evolution of plants around the world,” says Professor Greg Jordan of Biological Sciences at the University of Tasmania.

The fagus, a shrub that is estimated to live for around 600 years, is one of Professor Jordan’s favourites. Its leaves are like woodchips that, before opening, are squeezed like a piano accordion in the bud, an adaptation that allows them to blossom in the spring.

“The story of the fagus is fascinating and extremely important to me, it represents a species that has been around for around 40 million years and that is a remarkable thing.

Fagus threatened as Tasmania heats up

However, despite surviving for tens of millions of years relatively unchanged, the fagus is now under threat.

Scientists believe the tree could become extinct as climates become hotter, drier and more fire-prone. And while the threat won’t wipe out the fagus within a year or even 10 years, Prof Jordan thinks it could happen within 100 years.

“The biggest threat is the increase in fires due to climate change. The story of the fagus is not so much about adapting to the world as it is about changing, but rather about clinging and clinging, in its own habitat, which is why places like Mount Field are so important.

The threat, following an increase in dry flashes, bushfires and other symptoms of climate change, is also impacting a range of other older native flora.

“The mountains of central and western Tasmania are home to a rather astonishing collection of relict plants. These include conifers, such as pencil, creeping and Mawson pines, but also a number of other shrubs. These are even older than the fagus and most of them are threatened by the same mutations.

“The big problem is that these species all tend to live together in fairly small, specialized habitats, such as at Tarn Shelf, Mount Field NP and the slopes of Cradle Mountain. [approx. 300km to the northwest]. So that means they are all vulnerable to the same fires and stresses.

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