For the Aboriginal peoples of Australia, the giant eucalyptus trees brush against the world of the spirits: the ancestors, gone up to the sky, can come back down to earth by way of the trees. From south-eastern Australia to Tasmania, these trees, sometimes more than a hundred metres tall, reign over a forest shaped by fire. Around one of them, 105 metres high, a web of interdependence comes to light that megafires and logging are now breaking apart.
Nearly three million hectares: the eucalyptus seems to reign there over acacias and black sassafras, but it is less a solitary monarch than the pivot of a network.
Born in the crown of a fern, the roots of the young trees then wrap around it, and they win the race to the light.For the Gunaikurnai people, the eucalyptus is a legacy of the Dreamtime, where past, present and future intertwine for those who know how to listen to the forest. Russell Mullett grew up there, spending whole days in it. Every eucalyptus, he says, is an umbrella for the ground: it filters the light and shelters the plants and animals of the understorey. When he began to carve a trunk, the tree feeling the same small pain as skin being tattooed, everything around him fell silent; then the birds got used to the noise. His elders knew that by removing the canopy you change everything that lives beneath it: they took a piece of wood, never the whole forest. The Europeans did not understand that here every element is connected to another, and deforestation followed the arrival of the settlers. Our eucalyptus is more than 400 years old; its trunk, 5 metres in diameter, soars to 105 metres. It owes its stature to millions of years spent with fire, which returns naturally every 75 to 150 years: by rising more than 40 metres above its neighbours, it towers over the furnace.
“Our connection to nature was taken from us”: Russell Mullett speaks of what the arrival of the settlers also cost his people.
All Aboriginal peoples have inherited the art of carving rock and trees; this pattern is, says Russell Mullett, “a drawing for future generations”.
Underground, the giant is no less immense: its roots go down as far as 50 metres and draw up water and minerals even in the depths of drought.At the foot of the giant, a bird plays the gardener. The ecologist Alex Maisey is in no doubt: without the lyrebird, there might be no giant eucalyptus trees. With its enormous claws, it turns over the leaf litter all day, all year round, and shifts the equivalent of thirteen tipper lorries of soil and leaves a year. To prove it, he fenced off two squares of forest and, in one of them, imitated the bird every month with a rake: that is where the most invertebrates lived. By stirring up the soil, the lyrebird brings seeds back to the surface, lets the rain soak in and makes the ground less flammable. Underground, the eucalyptus depends on another ally: the truffle, whose filaments attach to its roots and bring it water and nutrients. To spread its spores, the truffle needs the potoroo. These small marsupials are “noses on legs”: they dig it up, eat it and sow it in their droppings. After a fire, explains the biologist Andrew Claridge, the smoke makes some truffles even more fragrant. “Without it, this forest might not exist.”
The lyrebird makes the plants that wallabies and wombats feed on grow: no other ecosystem-engineer animal has as great an impact.
His enclosures, three metres by three, closed off for two years, show it: by scratching at the litter, the bird itself raises the prey it feeds on.
Potoroos, truffles and eucalyptus have evolved together over thousands of years; the filaments of a single truffle stretch across tens of metres.The eucalyptus does not merely survive fire: it fans it. Its leaves are laden with flammable essential oils, its bark peels off in long strips that the wind carries away as burning shreds, and its candelabra shape carries the heat from one tree to the next. This sacrifice eliminates its competitors. Once the fire has passed, buds hidden beneath the charred bark burst into green shoots; its seeds, released only by heat, fall onto soil fed by the ash. When young, it grows several metres a year, and becomes a springboard for a small animal threatened with extinction, the greater glider. The ecologist Kara Youngentob counts them at night, in the rain. Few animals can digest these toxic leaves; yet no two eucalyptus trees of the same species share the same chemistry. Mapped by plane and by drone, this chemistry explains why the gliders live here rather than there. “We are shaped by the place where we live.” The scars left by fire, lightning and insects also hollow out cavities in the giants on which more than 150 species depend.
The ultimate escalation: at the heart of the blaze, the eucalyptus even gives off methane, which adds an explosive touch to the flames.
They are called epicormic buds: this “resurrection foliage” restarts photosynthesis, and the ash enriches the soil with potassium.
Like the koala, the greater glider digests these leaves thanks to a microbiome that breaks down their toxins; it comes out only at night.For forty years, the ecologist David Lindenmayer has been monitoring 200,000 hectares of forest. Every plant has its defence: the tree fern regrows from the top, and the seeds that fall into its crown germinate there with a two-to-four-metre head start on their competitors. But a normal, patchy fire should only come every 75 to 150 years. Human activity has made fires more frequent and more violent: a megafire exceeds a million hectares, and Australia has had four in twenty years. The fires of the 2019-2020 “Black Summer” burned an area the size of the United Kingdom. Forests that have been felled and then resown, too dense, catch fire faster, and climate change is drying them out. In Tasmania, helicopters burn the clear-cuts, and with them everything that lives in the soil, from echidnas to truffles. The activist Lisa Searle climbs into the trees to block the machines of a mine that wants to clear 285 hectares for a toxic waste pond. She would like to give this land back to the Aboriginal people, and tell them she is “truly sorry for everything we have done to these forests”.
Here, an old-growth forest burned in 2009 is regenerating: David Lindenmayer has the trees, the structure of the vegetation and the young seedlings measured.
So uniform and so intense, megafires destroy the refuges that biodiversity needs to survive.
In five years, the mine has been able to clear only a small area. For Lisa Searle, “the only solution is to put our bodies in their way”.“When you come into the forest, everything speaks to you. If you hear nothing, it’s because you’re not listening. Even silences have meaning.”Russell Mullett, Gunaikurnai people
“L’arbre qui cache la forêt is fascinating. […] The series goes beyond the trees themselves and the forests it depicts, to remind us of the complexity and importance of these ecosystems.”Mònica Planas Callol, Ara (Barcelona)translated from Catalan · July 2026
“Sumptuous images, a dreamlike voice-over, a hypnotic soundtrack […]. Beneath the trees, we marvel at the intertwining of the infinitely small and the infinitely large. […] By celebrating the majesty of the setting, L’arbre qui cache la forêt urges us to preserve it.”Ouest-FranceJune 2024