Is there some sort of key to understanding eucalypts? Dean has started making his own, a way of appreciating the subtle differences between the more than nine hundred eucalypts on his property. Here, E. brachycalyx, another Mallee, growing up to the coastal fringe of the Nullarbor Plain. Multi-stemmed, pith glands, shiny leaves, and flattened bud caps. But you have to know the differences, and how can you, unless your head’s full of a hundred fruit shapes, reniform cotlyedons, lanceolate leaves? Easier to imagine Andrew at work, planing, caulking. Up and down the rows, until one is overcome by a sort of guilty monotony.

So what is this tree that holds a sort of magical sway? As a kid, the grey-green blur you drove past on your way from one city or town to another. An unfortunate mess, ripe for clearing. As it always has been. Pioneers rolling stone-filled drums across the Mallee, clearing skeletal soils for sheep and wheat. Patrick White’s Australian Everyman, Stan Parker, arriving in the bush, driving between two big stringybarks and stopping, the horse ‘shaggy and stolid as the tree’. The animal taking root in an unpromising landscape. ‘The man’ (no different to ‘the tree’) striking the eucalypt with an axe. ‘It was the first time anything like this had happened in that part of the bush.’ But not the last.

Two hundred years of clear-felling.

Peregian Springs on Queensland’s Sunshine Coast. The usual line about hinterland, unspoiled beaches, and nearby national park, but progress always has a price, in this case, the clearing of five hectares of old growth scribbly gum (E. racemosa) forest. Thirty homes, and commercial developments, although Sunshine Coast Environment Council (SCEC) spokeswoman Narelle McCarthy explains that ‘the community are not going to stand by and watch vegetation that is wildlife habitat destroyed’. Developer Forrester Kurts Properties (FKP) seems to understand that ‘development work like land clearing can be difficult for the local community’. A difficulty that we still struggle with today.

An aerial view of Peregian Springs (photograph by Linda Fitzgerald, Wikimedia Commons)

Dean Nicolle’s Currency Creek Arboretum is the result of a lifetime’s interest in eucalypts. On gentle slopes overlooking the Coorong, more than nine hundred species (8,000 plants) move in the breeze off the Southern Ocean. A mix of Eucalyptus (more than 800 types), Corymbia (ninety types), and Angophora, or the ‘apples’ (so named for their similarity to apple trees). Angophora, with true petals, and both Eucalyptus and Corymbia favouring hardy bud caps. Angophora, with its leaves arranged opposite each other along the branch, but Eucalyptus and Corymbia (mostly) favouring alternate leaves.

Looking out on this sea of gums, it becomes apparent that the devil’s in the detail; the minor variations of habit and bark, from the chaos of a ribbon gum to the messages of the scribbly gum smooth, mottled, granular, each evoking a distinctive landscape or memory. The boxes, the stringybarks, the bloodwoods, a sort of mappa mundi of Australian landscapes, both physical and cultural. The high country and tropical species, struggling with Currency Creek’s cold mornings; the blue gums from Tasmania and South Australia, the smell of lemon, all crowded onto a vellum map that, it seems, would take a lifetime to understand.

We walk past paddocks full of grazing sheep and cattle, the remnant redgums (E. camaldulensis) along the dry creeks, a scattering of pink gums (E. fasciculosa) and lonely blue gums (E. leucoxylon). When Dean’s father, a retired commercial grower of cymbidium orchids, realised his son’s passion for the genus, he decided the teenager couldn’t keep planting gum trees in the family garden. To him plants were money; to his son they were a life’s work.

I try to fathom this devotion. Dean isn’t sure himself. Starting here, with the yates, a group of eucalypts from south-west Western Australia. Eucalyptus macrandra, the river or long-flowering yate, a four-to-ten-metre-tall Mallee with smooth bark varying from grey-green to coppery-orange. Its elongated bud caps revealing Splice-coloured flowers on hot summer days. Not to be confused with the Stirling Range yate, slightly shorter, with pale grey bark, the same long, horn-shaped bud caps, and similar yellow-green flowers in winter and spring. I become a budget Sherlock, trawling the undergrowth for an understanding of what makes subseries Cornutae different from subseries Liberae (and that’s before we start on the bushy yates, and their various subspecies). Eucalyptus megacornuta, with its long, warty bud caps, used by generations of West Australian kids to scare their younger siblings, chasing them around backyards with these tumorous witch fingers, pulling off the bud caps to reveal little green shaving brushes.

Eucalyptus cornuta, eight to twenty metres high, tallest and grandest of the yates. A hard wood favoured, back in the day, by wheelwrights, sweet nectar for honey, a fast-growing specimen used for coastal shelter. First described by French biologist Jacques Labillardière (1755–1834). Born into a large, poor, Catholic family, he studied medicine at the University of Montpellier then moved to Paris and spent his days in the Jardin du Roi. Thence to London, where Labillardière met Joseph Banks. He refined his study of exotic plants before returning to Paris and signing on to an expedition to the Near East. In 1791 the now well-respected botanist set sail for Australia as naturalist on the Bruni d’Entrecasteaux expedition, stopping at south-west Australia, Tasmania, and New Zealand. He assembled a large collection of botanical samples, which were then confiscated by the British upon the expedition’s arrival in Java. Luckily, Banks helped secure the return of this material after Labillardière’s return to France: ‘... the right of the Captors to the Collection should be on this occasion wav’d and that the whole should be returned to M. de Billardiere ...’  The material was returned, and eventually described in the two-volume Novae Hollandiae Plantarum Specimen (1804–6).

An aerial view of Dean Nicolle's Currency Creek Arboretum, 2017 (photograph by Dean Nicolle)

Labillardière’s book, with its 256 black-and-white images, was the definitive text on Australian flora until Robert Brown’s Prodromus (1810), a book that sold so poorly it was withdrawn from sale. But it was Labillardière, wandering the forests around Tasmania’s Recherche Bay in April 1792 and January 1793, who first described species as diverse as Tasmanian blue gum (E. globulus) and the carnivorous Cephalotus follicularis, as well as a range of bryophytes. He even defined new genera such as Calytrix, with his excellent grasp of Latin, the universal descriptor of plants. Labillardière married language with science (as W.G. Sebald said, ‘Scientists very frequently write better than novelists, and so I tend to read scientists by preference ...’).

A family history, from now to then, names breeding in the shadow of the past, our provenance set out precisely for any idiot to understand. Andrew Darling begets John, begets William, down through the years, as botanist Ferdinand von Mueller sets to work, and, following him, Richard Baker, Joseph Maiden, through to Dean Nicolle. Either way, only a few generations back to Mary Anne, my gran, lost in her own key of time, fog on the Bleak House hills of Currency Creek, and all I have is a reference someone wrote for her in 1932. (‘Miss M. Dawes has been in my employment for the last four years. She is an excellent cook, smart and efficient ...’)

The wisdom of plants was always there. Benedictine Abbess Hildegard (1098–1179) favoured lavender oil for lice and rheumy eyes. Sitting in her Mainz monastery, composing madrigals, studying science and medicine, burning lavender sprigs to ward off evil spirits. At the same time, Aboriginal people were using eucalyptus infusions for sinus congestions, pain, and colds. White sails in the sunset, and ship’s surgeon Dennis Considen starts distilling oil from Sydney Peppermint (E. piperita) only a few weeks after the First Fleet’s arrival in 1788. A few years later, colonists are using basic stills to make their own oil. Soon, von Mueller convinces Joseph Bosisto to set up a commercial distillery just outside Melbourne. Bosisto sees this as a great opportunity for his Richmond pharmacy. In 1854 he starts producing oil from the Narrow-leaved Peppermint (E. radiata). In 1882, with investors Alfred Felton and Frederick Grimwade, he establishes the Eucalyptus Mallee Company and builds Australia’s biggest distillery at Dimboola. He pays local unemployed and Indigenous men to cut branches and haul them in carts to the still. The vegetation is steamed in steel vats, separated from the water, bottled, and sent off for domestic and overseas use.

Bosisto works tirelessly promoting the oil until his death in 1898, making it the accepted Victorian treatment for ‘rheumatism, sprains, wounds, coughs, colds & c. Beware of imitations!’ Generations of Victorians knew ‘Doctor’ Bosisto, dispensing advice from his Melbourne shop. Always pushing his favourite lines: ‘Syrup of Red Gum’, having ‘a mucilaginous astringency [that] renders it effectual in all affections of the mucous membrane of the Stomach and Bowels, inducing a feeling of repose and tranquillity’.

Not that he was some sort of confidence man. ‘Bos’ was a frilly-shirted, late-Victorian man of science. There was some basic knowledge of eucalyptus oil composition in the 1870s (most notably from French chemist F.S. Cloez, studying Tasmanian Blue Gum, E. camaldulensis, in newly laid-out European plantations). Cloez isolated ‘eucalyptol’ (cineole), and later, at the beginning of the twentieth century, several Australian chemists identified the oil content of different species. Bosisto believed eucalypts were a ‘Fever Destroying Tree’. The oil was popular with everyone from prime ministers to the street kids of Jolimont and West Richmond (whom Bosisto represented as a member of the Victorian Legislative Assembly). Perhaps he truly believed eucalyptus oil could make a tubercular bacillus or influenza virus ‘die at its opening day’.

Australia, for half a century after Bosisto’s death, was the world’s biggest eucalyptus oil exporter. Then, with the establishment of overseas eucalypt plantations, this declined. Now, Brazil and China dominate the world market. But Bosisto’s continues, courting an over-prescribed world, even selling floor cleaners, all the time promising a ‘cleaner, healthier life, without harmful chemicals’.

The smell lingers, our most powerful connection with the past. The olfactory bulb, running along the base of the brain, rubbing up against the amygdala and hippocampus, emotion and memory stores for the years, the decades we’ve left behind. Andrew Sholl, media consultant and husband of Nikki Gemmel, described why the couple felt the need to return home from London: ‘And then there was the call of Australia, the call to come back home. Nikki would wake up in the middle of the night desperately homesick for the, the smell of eucalyptus. Deadly seriously.’

South Australian writer Barbara Hanrahan, living in London, remembered her childhood in Adelaide, the streets of Mile End, the eucalypts shedding bark beside the Wheatsheaf Hotel. Recording these memories in her classic The Scent of Eucalyptus (1973). Although eucalypts are barely mentioned. More, the memory, the smell, the sound of lanceolate leaves rustling on a shingle beach. When she is sent on a youth camp to Mount Lofty, she finds an empty box and decides to fill it with ‘beautiful things’, as she did, in her London bedsit, reconstructing a life. ‘My jewels were toadstools, an empty snail-shell, ivy leaves that looked like stars, pebbles that were cool against my cheek, some wattle, gum leaves with holes, a feather. My jewel-case became a garden ...’

The landscape morphing from Summer’s Night’s Dream to Mallee. A castle at Springton, sixty kilometres north-east of Adelaide. The story of a man who lived in the hollowed-out base of an old river red (E. camaldulensis). Johann Friedrich Herbig found it amenable, until he married Anna in 1858. After the birth of their second son, they decided enough was enough and Johann built a hut. By 1867 Friedrich had paid off his land, finished the hut, and fathered another four children. By 1885 there were sixteen in all. And the river red prospered. Six metres of floor-space, twenty metres tall, and up to five hundred years old. Kept as a sort of family souvenir, still visited today by thousands.

The Herbig Family Tree in Springton, South Australia (photograph by Abi Skipp, Flickr)Similar trees have been home to Indigenous Australians for tens of thousands of years. Natural, or burned-out, cavities. Or the use of vegetation from eucalypts to make goondies, or temporary dwellings, in contrast to more permanent type structures built elsewhere (such as the volcanic stone dwellings of the Gunditjmara people in south-west Victoria).

Our understanding of the eucalypts coincides with our grasp of this continent, an eighteenth- and nineteenth-century take on morphology, cells, reproductive and evolutionary strategies, leading to the work of Darwin and Lamarck, and beyond. Anton van Leeuwenhoek grinding 550 lenses to inflate the microscopic world to 270 times its actual size, allowing Robert Hooke to describe the bodies of hairy fleas, leading to a scientific obsession with seeing, knowing, understanding an unknown planet of small things (as French, Dutch, and English ships replaced micro- with macroscopic journeys across the Pacific and Indian Oceans). This astounding polymath, Hooke (artist, watchmaker, technician, surveyor of the post-Great Fire London) describing all of this in his famous Micrographia (1665). Cork, too, with its cells, these small units of life that would reveal their secrets over the next century.

This leads to a room in the British Museum in the 1770s, where a seconded French botanist, Charles-Louis L’Héretier de Brutelle, sat examining a specimen forwarded by the botanist on James Cook’s third expedition to Britain’s latest land acquisition. David Nelson had collected the specimen (E. obliqua) on Bruny Island, and now de Brutelle was examining its distinctive bud cap (operculum), seemingly in place to protect the plant’s reproductive parts from a harsh environment, only shedding under pressure from the developing stamens. The flower bud seemed ‘well’ ‘covered’ (‘eu’ ‘calyptos’) and a genus was born. Soon after, as the First Fleet were pitching their tents at Botany Bay, de Brutelle published his description of E. obliqua in London.

None of this would have been possible without the gradual accumulation of information that began with Theophrastus, three hundred years before the Christian millennia. This remarkably ‘scientific’ description of plants, their growth structures, reproductive strategies, all gathered in the nine volume Historia Plantarum. Theophrastus kept refining his work up until his death, devoting his life to the subtleties of leaf margins, anthers, and filaments, as well as the uses plants had in what passed as medicine.

Here, in the first volume, he describes the differences between trees, shrubs, and perennials, and observes that some trees (silver fir, for instance) have leaves that are always opposite each other on the branch, while others are irregular. In 1797 the English botanist James Edward Smith describes the Sydney Blue Gum (E. saligna), with its alternate leaf arrangement. In 1922, Joseph Maiden described the disjunct leaf arrangement of the Port Lincoln Mallee (E. conglobata), first classified by the nineteenth century’s premier botanist, George Bentham. Throughout, a language and legacy of detail accumulate like scale, describing and refining each detail of the hundreds of eucalypts.

A proliferation of keys, books (coffee table and scholarly), essays, and field guides to a plant that has continued to colonise the world. In the 1850s, for example, the fast-growing E. globulus was taken to the Californian goldfields by Australian prospectors and planted as a source of wood for mines, fuel, housing. In the following decades, it was laid out in plantations to provide wood for the growing railway network. In a letter to the Pacific Rural Press from September 1900, a reader asks, ‘Will it do to plant eucalypt trees in the Santa Cruz Mountains on sandy hills between Glenwood and Felton? I wish the trees for fuel and for the sake of the landscape as well.’ The editor explains, ‘As we had never seen any eucalypt in that region we appealed for information to Mr E.F. Adams of Wrights, an old resident and a close observer. He writes that he does not remember seeing a eucalyptus in the Santa Cruz hills... [but] he can see no reason why they should not grow on the sandy hills ...’ This unfussy expatriate, putting down roots in some of the world’s worst soils.

This iconic plant. But what does that mean? More adapted to Australian conditions, our tree, the bush that surrounds and consumes individuals in Australian story telling? A young Eileen Joyce (Suzanne Parrett) skipping through the scrub in the 1951 film Wherever She Goes. Here, one of Australia’s most successful pianists, as a ten-year-old, drawing inspiration from the rosellas in nearby gum trees, coming across a ‘bushie’ playing his harmonica, as the hills (bleached blue by a microclimate of Bosisto’s eucalyptus oil) provides the backdrop for this prodigy’s early wanderings in music.

Eucalypts are highly adapted to Australian conditions. Their tough, inedible leaves closing stomata as they hang low in the afternoon sun, shedding leaves and bark in summer; dropping deep roots in search of water; making do with the scant minerals in so many of our skeletal soils. Once, the poor cousin to rainforest species that covered much of the continent; later, adapting to the drying effects of early climate change to become the dominant species in most Australian forests, woodlands, and scrub. Then the storms, lightning, fires that affected other genera. The eucalypts responded with thick bark to protect their heartwood; the stimulation of leaf buds; epicormics tubers sprouting, weeks after fires, or seeds, deep in the ash bed, stirring to life.

One eucalypt becoming many, dozens, hundreds, over millions of years of adaptive radiation, as a new climate produced the Ooldea Mallee (E. youngiana), colonising dunes and swales with its proliferation of stems, thick leaves, bark falling away in ribbons, its pyramidal seeds burrowing into the sand. Or, not so far away, the mountain ash (E. regnans), one of the tallest trees in the world (often growing to more than ninety metres), taking advantage of high rainfall forests, living for hundreds of years until a fire comes along, stretching its enormous arms to create rainforest understorey. Or perhaps the most adapted (and common) eucalypt of them all: the river red (E. camaldulensis) the thirstiest, most versatile. Best known, each shade of its cream-brown trunk is reimagined in a hundred Hans Heysen paintings. Osmotically sucking from flooded creeks, but winding down its droughty metabolism. This marvel of reproduction, making up to 250 million seeds per hectare per year, waiting for insects to help pollinate; adapted to a wide range of conditions, drinking through its trunk, if needed, sending up roots for air during floods, growing up to thirty metres during its five-, six-, seven-hundred-year life span (some specimens are thought to be closer to a thousand years old). This marvel of adaptation, with its termite-resistant wood (making it a target for colonial home builders and sleeper cutters), provides habitat for hundreds of insects, birds, mammals such as the sugar glider (Petaurus breviceps), and reptiles like the carpet python (Morelia spilota).

The sixty-six thousand hectare Barmah–Millewa Forest in Victoria’s Murray Valley National park is the largest stand of river reds in Australia. Here the tree flourishes, taking advantage of artificial ‘watering events’ that see between three and four hundred gigalitres of water released onto the Millewa floodplain in alternate years, replicating natural flows. Allowing the trees to flourish, the growth of native Moira grass around floodplains and creeks, the spawning of Murray cod and golden and silver perch, as well as providing habitats for colonial waterbirds such as the straw-necked ibis and royal spoonbill. Traditional Aboriginal (Yorta Yorta) country, spotted with scar trees, reminding us of the tens of thousands of years this country provided manna for Aboriginal people living around the lakes and creeks, hunting, gathering food, still sleeping in the wetlands beside pre-Christian middens.

The river red is at the centre of this well-managed system. But it’s not always like this. In 2011, Adelaide’s Cohen Group announced the $100 million redevelopment of Burnside Village Shopping Centre. The centre, full of high-end brand names such as Chanel and Oroton, promised great things: more retail space, and a café-dining area fully enclosed with glass. Problem being, the hundred-year-old river red in what was to become the hippest meeting place for Adelaide’s Sass & Bide set. Many warned of the tree’s demise, but the Cohen group insisted they had thought of everything. The canopy was built, including a louvred section around the tree to let in wind and rain. On opening day, the camaldulensis seemed happy enough. Within a year it had turned brown all over.

An August 2013 article in the Eastern Courier Messenger explained, ‘As the death knell sounded on Adelaide’s most talked-about tree, no one was really surprised.’ Some claimed the Cohens had always known that a river red couldn’t survive in ‘a giant, coffee-fume filled glasshouse’. No intermittent flooding here; or insects, or anything, really. ‘When the tree’s health began to visibly decline last year [2012] ... there were phone calls from arborists, glass manufacturers and even a “tree whisperer”, who explained she had been to visit the tree and it had confided in her it was dying.’

Burnside Village Shopping Centre, 2011 (photograph by Aaron Pocock, Buchan Group)

When the controversy ramped up in 2013 the Cohen Group hired a public relations firm to sort it out. The family matriarch, Pat Cohen, flew in national experts who gave the tree regular nutrient injections. By July, Cohen had to concede that the tree was, in fact, dead. After it was removed, the centre manager explained that the river red’s spirit would live on. Some of the wood was auctioned for charity, some was given to local wood-turners and sculptors, one of whom made wooden bowls incorporating the shopping centre’s logo. Local artist Domenic Roscioli was commissioned to make benches and sculptures for the centre from the wood. Waste not, want not despite the critics saying that cappuccino was always going to triumph over camaldulensis. Basically, the tree was air-conditioned to death. The misting system and UV lighting the Cohens had installed did nothing to slow or arrest the inevitable. If any good did come from this five-year fiasco, it was an understanding of values, and how trees are still seen, in some places, as a liability.

Fire, too, is a constant in the Australian landscape. The last million years has seen our continent warm and dry, the decline of lush forests in favour of grasslands and deserts. Botanically, the survivors were the best at adapting. Paperbark (Melaleuca), for instance, re-sprouting from epicormic buds protected by thick bark doubling as a starch store for the new growth. Or the Gondwana proteas, with their deep underground stems covered in dormant buds, triggered by the hot, intense fires of the old Gondwanaland forests. But mostly eucalypts, a group that has not only learned to deal with fire but to use it. Here, the blue-leafed Mallee (E. cyanophylla), shedding its rusty bark in strips and ribbons, this low-nutrient forest trash waiting for fire, flaring up, promoting a short, intense heat that fails to damage the heartwood, sending out flares to replicate this effect across the Mallee.

Or a different approach, the messmate stringybark (E. obliqua), with its thick, fibrous insulation protecting the tree from fire. This tall, forest specimen stretching skywards in search of light, raising its vegetation from the fire-prone forest floor. Eucalypts with reserve leaf buds, biochemically triggered by the heat of fires, or, towards the base of trees, lignotubers waiting to re-sprout. Mostly, the eucalypt leaf with its volatile oil, catching, flaring, but burning quickly to avoid damage to the tree.

Or the release of seed triggered by fire in species such as mountain ash (E. regnans). Here, a towering forest specimen with no insulating bark, lignotubers, or epicormic buds, making it vulnerable to fire. Instead, a few days after fire, millions of seeds drop into the still warm ash, settling and waiting for winter rain, harvesting light from the naked canopy. Germination, hopeful roots and stems. Twenty years later, maturity, seed-set, and perhaps five hundred years’ of growth, as the cycle repeats. Unless, as on the fringes of Australia’s capital cities, we do our best to prevent fires.

The morning of 16 August 1983. Hot, again, after a dry, roasting summer, and in South Australia, low humidity, strong 100 kilometre northerlies (and later, a dust storm). It was well above forty degrees when I rode home from school. The wind held me back, the fan-forced oven on my face, dirt in my mouth, the Adelaide Hills alight. The first fire of the day had already been burning for four hours (starting near McLaren Flat), but multiplying, exponentially, through the afternoon. The same thing happening in Victoria, on this, the Christian celebration of Ash Wednesday. Charted on fire maps, the deep reds of mid- and high-forties temperatures showing the chain of events unfolding.

One hundred and ten fires (eight major fronts) burning across two states, and later, a south-westerly wind change that provided new fuel loads, whipped up firestorms and trapped some of the twenty-eight South Australians (and forty-seven Victorians) who died in cars, on farms, on roads, trying to escape. So much vegetation, and smoke, stopping any chance of organising an effective response. On Yarrabee Road, in the Adelaide foothills, Adelaide journalist Murray Nicoll watched his house burn. Trapped by the flames, he broadcast a description. ‘We are in deep trouble. We can’t see any houses. Greenhill Road is just wiped out. There are dozens of people here with me we can hardly breathe. Things are white with heat and smoke. There are women crying, and there are children here.’ A burned-out CFS truck was left in our school yard a few weeks later. Someone had died in it, apparently, and we needed to remember.

A familiar trope to most Australians. Victoria’s catastrophic Black Thursday fire of 1851 reads like some sort of prequel to 1983, and the even more devastating Black Saturday bushfires of 2009, in which 173 people died. As each event is given a religious handle, as though men and women, horses and dogs, faced some purgatorial trial, emerging cleansed, the subject for art, perhaps. Such as Black Thursday February 6th 1851, by William Strutt, the first in a long line of Australian landscape painters who have dealt with the drama of fire. Strutt’s painting is a muddled, apocalyptic vision in tones of gravy-brown and red, portraying a blaze that devastated a quarter of Victoria. The same combination of extreme heat, northerlies, low humidity, high fuel loads, the tail end of a prolonged drought. Or Russell Drysdale’s 1944 painting Bush Fire, an entirely new take on landscapes stripped of romantic associations. The burnt ochre and yellow of the remains of a homestead silhouetted against a bleached sky. Here, the feeling that the bush wasn’t worth all the effort. As Geoffrey Dutton explained in 1960: ‘Drysdale saw it all, and recorded it with an honesty unattempted by the writers, who wanted to stir sympathy or indignation.’

Australian bushfires occur less frequently now than in any time over the last 10,000 years. In a way, our nineteenth-century Turneresque take on fire, and the bold headlines of 1980s newspapers, ignore the reality of the Australian bush. Stephen Pine called eucalypts ‘an occupier of disturbed environment; a fire creature’. Like the Wandoo (E. wandoo), relying on ash beds to germinate seed, or regnans, casting its lot with wildfires that used to burn forests with far greater frequency than today.

The gum tree as culture: 28 December 1836, Governor John Hindmarsh and South Australia’s first settlers came ashore at Glenelg, seeking shade beneath a red gum (E. camaldulensis) as Hindmarsh called upon the colonists to ‘conduct themselves on all occasions with order and quietness’; as the country was explored, and Robert O’Hara Burke and John Wills stumbled along the north bank of the Coopers Creek, finding no consolation in the words carved into the flesh of a coolibah (E. coolabah):

B LXV Trunk, Creek Side
DIG 3FT NW Trunk, land side
Dec 6 60 April 21 61 Limb upstream

Thirty years later, under a ghost gum (C. aparrerinja) outside the Barcaldine railway station, striking shearers blockaded the arrival of scab labour from the south, followed, on 9 September 1892, by the reading of the manifesto of the Queensland (later Australian) Labor Party in the shade of what would become known as the Tree of Knowledge. It didn’t end well for this, the most important political tree in Australia: a vandal injected glyphosate into its trunk in 2006. (The Australian Labor Party offered $10,000 dollars for information about the culprit.) A similar fate to South Australia’s ‘old gum tree’, encased in concrete after its death in 1963. But the ‘dig tree’ is going strong.

On the subject of political trees, here is Singapore’s prime minister, Lee Hsien Loong, standing in front of a gum tree during (to quote Loong) ‘the golden hour in Adelaide’ (sunset) in June 2017. Taking a photo (his shadow included) after a week’s holiday in the hills and posting the image to his 1.17 million followers on Facebook. The long shadows, the grand old gum, forming a backdrop to Loong’s political problems. Loong leads Singapore’s People’s Action party, founded by his father, Lee Kuan Yew, in 1959. A wealthy family. So when Loong’s two siblings, Lee Hsien Yang and Lee Wei Ling, wanted to demolish the family home for a major redevelopment, Loong blocked them. They accused Loong of abusing his powers (against their father’s dying wishes). The feud became increasingly personal until (according to Adelaide journalist Tom Richardson), ‘LHL [took] the extraordinary step of apologising to the city state’s citizens for the embarrassment the bitter public feud has caused, vowing to clear his name in a speech to the legislature this week, at which government MPs will be granted a rare free vote.’ All this nastiness softened by a picture of a gum tree. The Facebook post attracted 17,000 likes and a thousand comments along the lines of, ‘Hope you push on from this unfortunate episode. LKY trusted you. We trusted him. Now, we also trust you.’

The gum tree as a symbol, a carrier of Australian values. Even in 1967, as filming began for a new children’s television series, Skippy the Bush Kangaroo. Thousands of suburban Aussie kids sitting in their Mr Sheen-smelling brick and fibro houses as Australian Everyboy, Sonny Hammond (Gary Pankhurst), nightly set off on adventures through the fictional Waratah National Park (Duffys Forest, north of Sydney) in search of rogue criminals. Sonny and one of his dozen kangaroos set free in Ku-ring-gai Chase National Park, the smell of scribbly gums (E. haemastoma) and Sydney peppermint (E. piperita) strong in the air, as developers cleared more of the same for the Australian Dream.

Robin Boyd, in The Australian Ugliness (1960), had warned that trees weren’t ornamental additions to suburban gardens, nestled between the letterbox and concrete Aborigine. On the other hand, he wrote, ‘the bush atmosphere is prized chauvinistically by people who would not dream of going beyond the suburbs except in a Jaguar’. Explaining that ‘gum trees here are probably too plentiful to command any respect, and the job of clearing is considered as inevitable for a homebuilder now as it was last century for a farmer’. Australian were arboraphobes, he said, noting that the Housing Commission in Perth was once persuaded by a ‘tree-lover group’ to ‘spare some of the native bush in an outer-suburban subdivision. The Commission agreed to leave two gums in each front garden. But six months after the estate was opened every tree had been removed by the occupiers.’

None of this in Waratah National Park. Sonny picks a leaf from a stringybark (as we all attempted, inspired by the 1970s reruns) and whistles across the canopy of narrow-leafed apple (Angophora bakeri). Although now this ridgetop woodland, too, has gone the way of what Boyd called our ‘Austerican’ dreams. The suburbs creeping north, the ‘Home of Skippy’ sign rotting in the leaf litter, the ranger headquarters (where Sonny received his nightly lecture from his father) locked up and forgotten, a few curious visitors peering in the acres of glass that keep the weather, although hardly the years, at bay.

Unfortunately, gum trees looked too, well, Australian. One exception, Boyd related, was the West Australian flowering gum (Corymbia ficifolia) that had managed to avoid the worst of the eucalypts’ scrappy canopy and messy bark. This showed that White Australia ‘has nothing against gum trees on racial grounds; it is simply unfortunate that so few of them are neat enough in their habits to be accepted’.

Watch, as the eucalypts head for Australia. Over what is now the Philippines (where Eucalyptus deglupta can still be found on Mindanao), New Guinea, adapting to a range of landscapes and climates on this journey south. Evolving smaller, tougher leaves set close to avoid water loss. Hard bark. Deep roots. And proof, in the genetics of New Caledonia’s Arillastrum, a monotypic genus of the family Myrtaceae with similar features to Angophora and Corymbia. Small, genetic changes over tens of millions of years, the least successful variants dying out in calcareous or saline landscapes, burnt brown by hot summers or their seeds washed away in seasonal floods.

It’s all in the genetics. The University of Tasmania’s Dr Rebecca Jones is a regular visitor to Dean Nicolle’s arboretum. Her research has involved using molecular genetic markers to determine if eucalypt populations are ‘at risk of extinction due to inbreeding and loss of genetic diversity’, as well as gauging the extent of clonality in (especially) Mallee eucalypts. Conservation genetics. According to Jones: ‘a field of research that uses genetic techniques to gain information about populations and species ... [this] is then used to formulate management strategies for the conservation and restoration of biodiversity’. Allowing us to understand questions such as ‘the genetic basis of variation in resistance to myrtle rust (which has recently arrived in Australia)’. Jones explains that her research at the University of Tasmania concentrates on restoration and conservation genetics, evolution and speciation, genome architecture and eucalypt breeding for pulpwood, timber, and bioenergy.

Global demand for eucalypt oil is around 7,000 tonnes a year (of which Australia supplies only five per cent). Beyond the world of medicine and cosmetics, research into a hydrocarbon component of eucalyptus oil, terpenes, promises new industrial applications. A 2012 paper showed that a catalytic process can convert terpenes into renewable, high-density fuels. According to the study’s authors, ‘The fuels produced by this process have net heats of combustion ranging from 137,000 to 142,000 btu/gal which are comparable to the tactical missile fuel JP-10.’ In the near future, terpenes found in eucalypts (primarily pinene and limonene) could be refined to adequate energy densities to combine with standard aviation fuels. Terpinen-4-ol could also be used to produce graphene, a two-dimensional carbon grid a hundred times stronger than steel (according to scientists David Kainer and Carsten Kulheim, ‘a square metre of graphene can support the weight of a house cat but weighs less than one of its whiskers’).

Jones explains, ‘There are so many [research] areas that need attention ... we are only beginning to capitalise on the 2014 release of the Eucalyptus grandis genome and so this is an exciting area in Eucalyptus genomic research.’ She believes that if speciation, divergence, and the distinctiveness of populations are understood, the management and use of eucalypts can be improved. For example, ‘the genetic basis of wood properties to help transform the forest industry from a pulpwood focus to producing solid wood products (e.g. sawn timber and veneer composites)’, or using adaptation genetics to understand ‘the selection of germplasm for ecological restoration and industrial plantings that will be resistant to rapid environmental change over the next century.’

Proclamation at the Old Gum Tree: a 1936 re-enactment of landing in S .A. of first settlers – Glenelg (State Records of South Australia, Flickr)

Genetics explains the success of eucalypts in the Australian landscape. Mysteries remain, however. For example, the yellow bloodwood (or ‘rusty jacket’), C. peltata, grows cheek-by-jowl with a lemon scented gum (C. citriodora).The former with its fibrous yellow-brown bark, the latter, smooth, and shedding, pale blue to brown, bleached like a Drysdale sky. Prompting the question, why so different in similar habitats?

Jones explains: ‘For example, the differentiation between two closely related Tasmanian eucalypts, E. tenuiramis and E. risdonii, may be the product of relatively recent changes in developmental timing. These closely related sister species are weakly differentiated genetically but are strikingly differentiated for developmental traits. E. tenuiramis, like most other eucalypts, flowers in the adult leaf phase, while the rare taxon E. risdonii rarely procures adult leaves and instead flowers while in the juvenile leaf phase.’

As we drive around his Currency Creek arboretum, Dean Nicolle explains that eucalypts have ‘different strategies to cope with something ... and that’s about all we can say with certainty, beyond that it’s all theories and hypotheses’. Eucalypts responded in different ways to the same environment. ‘Under any environment you generally have two or three different eucalypt species growing together, but they have different features.’

As we explore these hills and valleys, hundreds of eucalypts growing limb to limb, related only by the time and place they were collected. Off in the distance, a few remnant redgums growing beside a creek; pink gums (E. fasciculosa) struggling on a hillside cleared for crops; a few South Australian blue gums (E. leucoxylon) providing shade for a sheep and cattle. Nicolle, from a young age, was fascinated by this singular tree. Growing up around his parents’ cymbidium nursery, devouring books such as Ivan Holliday’s A Gardener’s Guide to Eucalypts (1980). Years later, this modern Noah, growing four of each species in uniform conditions, exploring the world of form. Barks, minni-ritchi, mottled, granular, and smooth; the peppermints, the boxes, the ironwoods, and bloodwoods; sparsely and densely reticulated leaves, and even the way oil glands bustle for room in the sun. All of these details and variations laid out in keys that take amateur botanists down paths that lead nowhere (the directions too confusing). Family trees, turning in on themselves, the subject of academic discussions that go on and on (‘I just try and keep out of all that’, Nicolle explains), the bloodwoods migrating from Eucalyptus to Corymbia as recently as 1995 (to the displeasure of some).

Something like Jorge Luis Borges’s ‘The Garden of Forking Paths’, a story about a novel about a world in which all possible outcomes occur simultaneously, creating a profusion of possibilities, only a few of which will ever connect. The protagonist, Yu Tsun, explaining that, ‘I thought of a maze ... which would take in both past and future and would somehow involve the stars.’  That is, temporal, not spatial. Not this profusion of rows in the Currency Creek cemetery, my ancestors hidden in the long grass of time (no one from my family had ever visited). Or similar rows of eucalypts from the south-west coast of Western Australia, transplanted to this cold cattle country, struggling to grow beyond their limits.

The thought returns: people are no more than the sum of their genetics. Andrew and Catherine moving from Renfrewshire to put down roots in this Currency Creek soil; to build boats and bake bread; to daily make one of two choices, again and again, that would lead to Row H, plot 5Y.

Carolus Linnaeus in Laponian costume, by Hendrik Hollander, 1853 (University of Amsterdam, Wikimedia Commons)When Carl Linnaeus published his Species Plantarum in 1753, a new order was brought to the naming of plants. Binomial nomenclature assigned a fore- and surname to the (what Linnaeus believed were) ten thousand types of plants growing under God’s careful watch. Now we know there are closer to 400,000 species of flowering plants alone, but as Linnaeus explained, ‘The first step in wisdom is to know the things themselves ...’ And what Linnaeus began in the name of God, (‘dumbstruck before the Kingdom of the Creator’), Jean-Jacques Rousseau continued in the name of Reason.

There he is now, twelve years after Linnaeus’s first edition of Plantarum, sitting at the window of his small hotel on L’île Saint-Pierre, exiled for (again) speaking his mind. He was addicted to thought, ideas, order, and tried to placate the urge by rote copying of musical notation. When this didn’t work, he ‘set out to compose a Flora Petrinsularis and to describe every single plant on the island in enough detail to keep me busy for the rest of my days. They say a German once wrote a book about a lemon-peel; I could have written one about every grass in the meadows ...’  W.G. Sebald later explained that it wasn’t so much about the plants as ‘the ordering, classification and creation of a perfect system’. A perfect system? Is that what botanists, artists, and illustrators of eucalypts long for a complete, definitive take on the genus?

Ararat engine driver Stan Kelly (1911–2001) published his first book, Australian Eucalypts in Colour, in 1949. The unassuming amateur artist started small, but set himself the challenge of painting all of the eucalypts. Travelling the country, like Nicolle, Jones, and a hundred others, searching for the next undiscovered specimen. Slowing his train, handing control to the fireman, jumping off and grabbing a specimen he would spend the weekend painting in his bedroom. Developing a range of greens to best describe each species. Meticulously observing leaf arrangement and venation, fruit shapes, flower colour. A tie and a tidy cardigan, telling his grandchildren the eucalypt was ‘Australia’s greatest asset and finest ambassador throughout the world’. His work (especially his Eucalypts of Australia, Volumes One and Two) is still admired and consulted for its detail, its precision.

Kelly was not the only one. An eight-year-old May Gibbs riding through the Western Australian bush on her pony. Stopping, sitting on a log, sketching some early version of Little Ragged Blossom. Or a twenty-year-old Hans Heysen, studying art in Paris, still smelling the big river reds around Hahndorf on hot summer days. This tree, somehow, part of the way he understood (as a seven-year-old from Germany) what it meant to be Australian. Later saying, ‘... the gum tree’s main appeal to me has been its combination of mightiness and delicacy mightiness in its strength of limb and delicate in the colour of its covering’.

To most Australians the gum tree is just there, lining creeks and highways. Like the Cazneaux Tree, a lone red gum standing near Wilpena Pound in the Flinders Ranges. Perhaps the most memorable image by photographer Harold Cazneaux. The 1937 photograph is slightly washed out; there doesn’t seem much hope: the few drought-dead branches, the orange soil, the rotted fence posts of early graziers. But it’s there today, still. Cazneaux called it the ‘Spirit of Endurance’. ‘One day when the sun shone hot and strong, I stood before this giant in silent wonder and admiration. The hot wind stirred its leafy boughs, and some of the living element of this tree passed to me in understanding and friendliness.’

The Cazneaux Tree, Flinders Ranges, South Australia (photograph by Jacqui Barker, Wikimedia Commons)

Maybe we don’t get gum trees because we don’t get Australia. The American novelist John Steinbeck knew why. ‘No one has ever successfully painted or photographed a redwood tree. The feeling they produce is not transferable. From them comes silence and awe. It’s not only their unbelievable stature, nor the colour which seems to shift and vary under your eyes, no, they are not like any trees we know, they are ambassadors from another time.’

Ste[hen Orr writes: I would like to thank Australian Book Review and its Patrons, as well as Eucalypt Australia, for continuing to support this very special sort of long-form writing. Also, the encyclopedic and ever-generous Dean Nicolle, and Rebecca Jones, whose insights and explanations made the most technical ideas simple. Their enthusiasm for eucalypts was infectious. As ever,any mistakes are mine.

This is the third ABR Eucalypt Fellowship we have offered. The Fellowship is partly funded by Eucalypt Australia, partly by ABR Patrons.