In early 2020, with the arrival of the coronavirus pandemic, every national park in Tasmania closed its gates to the public. They remained closed for six weeks, between late March and mid-May. While the decision was a necessary public health measure, the timing of the closures could not have been more disappointing for fagus fanatics.
Fagus, or Nothofagus gunnii, is Tasmania’s only native deciduous species. From mid-autumn the iconic crinkle-cut leaves turn gold, orange and red in a display that attracts thousands of admirers from across the country. By late-May, the spectacle is on the wane and the trees rest bare-branched until they resprout their greenery in spring.
Nothofagus gunnii is restricted to remote alpine areas of central and south-western Tasmania, with almost three-quarters of the population protected within the Tasmanian Wilderness World Heritage Area. However, fagus was once widespread through the ancient landmass of Gondwana. Fossil records of this deciduous beech, dated at 35 million years old, have been found in Antarctica and at Cethana in northern Tasmania. Related species can be found in other ex-Gondwanan regions, including South America, New Zealand, Papua New Guinea and New Caledonia. Now, fagus is a living fossil representing one of the oldest lineages of flowering plants in the world.
I used to make the pilgrimage to Mt Field’s Tarn Shelf most autumns, to marvel at the gnarled fagus trees twisting down the hillsides and over boulders around the mountain lakes. The tarns were often so still their reflections would double the yellows, reds and coppers of the foliage. At other times a misty veil would partly obscure the scene, muting the colours but creating an enchanting scene of alpine alchemy.
Now on my visits to Mt Field I am accompanied by a tribe still too young to trek as far as the tarns, but around the more accessible and equally picturesque Lake Fenton are fagus-forested paths that glow with autumn colour and inspire the obligatory excited squeals. The oldest known fagus tree is thought to be 350 years old, and it is easy to imagine such an ancient among these forests.
However, there are now concerns that even in these last refuges, fagus may be under threat.
Fagus is a fussy friend, preferring to live in cool, wet climates. At 1,000m above sea level, and with annual rainfall of almost 2,000mm, places like Mt Field’s Tarn Shelf and Lake Fenton are ideal fagus territory. But as the climate changes, alpine areas like these are beginning to warm and dry. This increases the risk of fire, which is known to decimate adult fagus trees and their seeds, preventing their ability to resprout.
Fagus seeds have no adaptation for wind dispersal, cannot spread far from the parent tree and do not store well in soil. This makes recolonising burnt areas from the perimeter a slow process. With such a restricted population of fagus now remaining, any further losses to their number or range could have significant impact on the survival of the species.
As we paid our respects to this Tasmanian icon this year, I was grateful to have had the opportunity to return once more. In a time of turbulence and uncertainty, the importance of these touchstones and traditions become ever more acute.
The column of adventurous hikers heading up towards the tarns continued steadily as we began our descent. Our youngest waved happily to each one as they passed and I smiled, looking forward to the day when we can complete the full pilgrimage and introduce the next generation to the magic of Tasmanian mountains in autumn.
Grace Heathcote is a Tasmanian writer. With a background in ecology and conservation, she has worked throughout Australia but has a soft spot for all things Tasmanian. Her writing has been published nationally, including in The Guardian, and her academic publications can be found in peer-reviewed journals such as Conservation Biology and Wildlife Research.