Put our forest giants on the record

Trees lured me from the land of the redwoods but Tasmania still plays down its wonders, says Yoav Daniel Bar-Ness

ICAME to Tasmania for the giant trees. As a child in 1980s Silicon Valley, I naively imagined that California’s significance stemmed from the very important fact that we had the tallest trees in the world. Yet upon arrival in Tasmania 20 years ago as a scientist studying our own tallest flowering forests, I was surprised to discover how little public presence the worldrenowned trees had in the tourism landscape.

It’s been a delight to see the upswell of enthusiasm for giant tree tourism in different sectors — online, in local government, and in the pages of the Mercury. I’d like to provide readers, and those in government and tourism, with an up-to-date snapshot of our globally superlative tall trees.

It’s of immense interest to many Tasmanians and mainlanders, to a subset of passionate tourists, and to scientists worldwide. I feel if we are all equipped with a toolkit of well-phrased talking points, we can more clearly discuss the opportunities and responsibilities these trees bring to the island.

My experiences touch on these directly. I have visited, documented and climbed several of our champion trees; conducted ground-laser measurements on our tallest tree, Centurion; and started Giant Tree Expeditions, the first specialist tourism operation focusing on these forests. I’ve also had the chance to conduct the first systematic measurements of the world’s broadest trees, India’s giant banyans, which form wooden networks 200m across.

As individuals to introduce, organisms to study, and physical environments to explore, giant trees have been a constant touchpoint in my professional life.

Fundamentally, statistics are a very limited way to understand ancient organisms. They do spark interest, but I believe we need to recognise all of the non-champion trees for their other attributes such as age, complexity and charisma. Like any scientific measure of the natural world, tree-nerd statistics aren’t absolute measures of eternal truth — they represent a snapshot in time using specific methods and tools.

With that said, I believe you should know Tasmania’s trees are globally premier in many ways.

The tallest flowering tree in the world is a Eucalyptus regnans in Tasmania, last measured at 100.5m tall. With one single overlapping measurement of a rainforest dipterocarp tree in tropical Borneo as a possible contender, the tallest known flowering plant in the world is growing in Tasmania’s Huon Valley. In November 2018, I measured and reported this Eucalyptus regnans, Centurion, at 100.5m +/- 0.4m. It survived the Riveaux Fire only two months later. There are non-flowering redwood trees taller in California, including the world’s tallest tree at 115.9m.

Tasmania is home to the tallest flowering forests in the world, with groves more than 85m tall. There are a handful of groves where several eucalyptus grow together over 85m tall. The only other forests of such stature are on the western coast of North America — but these are nonflowering species such as redwoods, firs, pines and cypresses.

Tasmania has the tallest trees and forest in the Southern Hemisphere, and the tallest trees and forests outside of California. Tasmania has the tallest trees and forests in Australia.

Tasmania is home to the world’s largest flowering plant by wood volume, a eucalyptus regnans just under 400 cubic metres. It’s worth adding that these statements may have quite recently and may in future apply to Victoria.

The list goes on. Tasmania’s East Coast kelp forests are the tallest underwater forests in the Southern Hemisphere.

We also have two contenders for the oldest living individual things on the planet, Huon pines estimated to be 10,000 years old and the King’s Holly calculated to be 43,600 years old. Add in many species unique only to Tasmania, and our extreme southerly location, and Tasmania is well endowed with both botanical and zoological superlatives.

Height measurements are, quite literally, onedimensional numbers, and they deserve a deeper explanation. Any published statistic is not only uncertain, but also out of date immediately. Forest soil and tree stems grow and shrink with temperature and moisture. Like humans, these trees are at their tallest for only a short period before they enter the more interesting and complex phases of life. As their summits decline, they continue to grow their branches outwards and develop the structural complexity that serves as wildlife habitat.

These simple statistics are the numbers that children and adults around the world yearn for as they learn about planet Earth. There are a surprising number of websites pointing to

Tasmania as a world capital for botanical champions, yet we have no consistent tourism strategy or investment in sharing these trees with the world. I recognise that there have been good faith efforts from several sections of society — forest managers, conservation organisations, private citizens, and journalists — to promote and discover these trees. More than a decade ago, the inter-agency

Giant Trees Consultative Committee stated one of its goals was to “promote opportunities for access to Giant Trees for recreation and tourism”. In 2002, Forestry Tasmania (now Sustainable

Timber Tasmania) published its objective to “promote with other forest managers a statewide tourism strategy for Giant Tree appreciation … participate in its implementation”. These written words have greatly inspired me, and I believe these remarkable trees are of great potential value as ambassadors for the natural world, as flagships for Tasmania’s international branding and as elements of our future prosperity through nature tourism. Yoav Daniel Bar-Ness is a scientist and a guide for Giant Tree Expeditions.