The Biggest Estate on Earth

by Bill Gammage

  There is a tandem puzzle. Typically, grass grew on good soil and trees on poor (ch 7). In 1826 Robert Dawson described country behind Port Stephens (NSW) as

  in general heavily timbered, and as usual, without underwood. After crossing a deep, and in some places a dry channel, which in rainy seasons would be called a river, the soil began to improve. The country gradually became less heavily timbered, and the views more extensive. This was in accordance with what I had been previously led to expect, and fully confirmed by my former observations, that the poorest soils contained more than treble the number of trees that are found in the best soil, being also much longer and taller. This, like most other things in this strange country, is, I believe, nearly the reverse of what we find in England.9

  In South Australia Edward John Eyre, a most competent observer, wrote, ‘For the most part we passed through green valleys with rich soil and luxuriant pasturage. The hills adjoining the valley were grassy, and lightly wooded on the slopes facing the valley; towards the summits they became scrubby, and beyond, the scrub almost invariably made its appearance’,10 and Charles Sturt observed,

  As regards the general appearance of the wooded portion of this province, I would remark, that excepting on the tops of the ranges where the stringy-bark grows; in the pine forests, and where there are belts of scrub on barren or sandy ground, its character is that of open forest without the slightest undergrowth save grass . . . In many places the trees are so sparingly, and I had almost said judiciously distributed as to resemble the park lands attached to a gentleman’s residence in England.11

  Near Gundagai (NSW) in the 1840s two tourists found ‘beautiful meadowland . . . bounded by sloping ranges of hills covered with grass, and thinly timbered. Generally speaking, all fertile lands in Australia appear to be characterized by these beautiful features.’12 Generally speaking that was so in the 1840s, but not now. Why did the most fertile land grow the fewest trees?13

  A few travellers puzzled at this. In 1831 William Govett saw summits behind Sydney ‘clothed with grass, which circumstance, considering the barrenness and excessive sterility which pervades all the connecting ridges, and that region of the mountains, is certainly very extraordinary . . . In general . . . the ranges are covered with short timber and scrub.’14 ‘The great peculiarity here’, RJ Sholl wrote northeast of Broome (WA), ‘as well as in the land to the north of the Glenelg, is the total absence of undergrowth bushes; between the widely separated thin and short trees there is nothing but grass and creepers. Let it be thin or thick, good or bad, tall or short, still it is grass.’15 At Omeo (Vic) about 1843 Henry Haygarth portrayed his perplexity vividly:

  The gloomy forest had opened, and about two miles before, or rather beneath us—for the ground, thinly dotted with trees, sloped gently downwards—lay a plain about seven miles in breadth. Its centre was occupied by a lagoon . . . On either side of this the plain, for some distance, was as level as a bowling-green, until it was met by the forest, which shelved picturesquely down towards it, gradually decreasing in its vast masses until they ended in a single tree. In the vicinity of the forest the ground was varied by gentle undulations, which, as they intersected each other, formed innumerable grassy creeks and open flats, occasionally adorned with native honeysuckles and acacias . . . Two remarkable conical hills, perfectly free from timber, rose in the middle of the largest plain . . . The whole, as far as the eye could reach, was clothed with a thick coat of grass, rich and luxuriant, as if the drought, so destructive elsewhere, had never reached this favoured spot.

  It was Omio [sic] plain. By what accident, or rather by what freak of nature, came it there? A mighty belt of forest, for the most part destitute of verdure, and forming as uninviting a region as could well be found, closed it on every side for fifty miles; but there, isolated in the midst of a wilderness of desolation, lay this beautiful place, so fair, so smiling.16

  Omeo’s historian wrote,

  When the first white men came to the Omeo Plains all the best country was treeless. On the lower foothills which bordered the plains, there were large gum trees, standing singly, and odd clumps of sally wood . . . northward and almost to the tablelands, about six miles away, the gum timber was dense, and known as The Forest,17

  and Thomas Walker thought the valley ‘the prettiest piece of country I have seen since leaving the Murrimbidgee [sic], very thinly timbered, indeed in many parts clear, with here and there interspersed a few trees or a clump or a belt, the soil sound and good . . . the sward close . . . the whole being intersected by lagoons: it is quite like a gentleman’s park in England’.18

  Other Gippsland travellers saw chains of plains,19 and in 1834 John Lhotsky confessed of similar chains between Gundaroo and Michelago (NSW):

  It is . . . a most remarkable, but not very easily explicable fact, that they are altogether destitute of trees of any kind, and only on the secondary hills or banks, which divide their plications, are some gum-trees thinly scattered, whereas large timber covers the main ranges . . . it is difficult to understand, how it is, that there is not even a vestige of incipient sylvification in the plains and downs themselves.20

  Charles von Hugel, a botanist, stated, ‘A plain like the Goulburn Plain is certainly an interesting phenomenon . . . as in the case of all the plains mentioned earlier, the soil is good—why is it that no trees occur on it, seeing that they grow splendidly when planted? There is no easy answer to this question.’21 In the same district Govett observed in 1832,

  The park-like forests of this County are relieved in many parts by plains, or portions of ground altogether destitute of timber. These plains vary in extent and form, some are hilly and undulating, while others appear a mere flat, and the generality of them possess a good soil. It appears as if the seed of the tree has never been, as it were, scattered upon them, for it cannot be disputed, that the trees which surround these plains would also vegetate upon them.22

  A century later TM Perry investigated these plains. He could find no soil distinctive to them or to the woodland around. Each could be ‘on identical soils’. He could not say why.23 This was land where trees grow now.

  Soil can regulate which plants grow where, yet Sturt saw trees vanish without any soil change, and puzzled at ‘the sudden manner in which several species are lost at one point, to re-appear at another more distant, without any visible cause for the break’.24 In the Dorrigo (NSW) brush in 1894 Joseph Maiden reported ‘plains which simply consist of grass-land, entirely destitute of trees, or dotted about as in a gentleman’s park. Usually the edge of the scrub and of the plain are as sharply defined as it is possible for them to be, as though a Brobdingnagian with mighty sickle, had there finished his reaping.’25 G Marks investigated in 1911, and found ‘open flats that never grew timber in their virgin state, yet they have similar soils to the timber areas that surrounded them, and apparently are identical in their chemical composition and mechanical nature’.26 By then Leichhardt had discounted soils. At Calvert’s Plains on the Dawson (Qld) he noted,

  It was interesting to observe how strictly the scrub kept to the sandstone and to the stiff loam lying upon it, whilst the mild black whinstone [basalt] soil was without trees, but covered with luxuriant herbs and grasses; and this fact struck me as remarkable, because, during my travels in the Bunya country of Moreton Bay, I found it to be exactly the reverse: the sandstone spurs of the range being there covered with an open well grassed forest, whilst a dense vine brush extended over the basaltic rock.

  A month later he added, ‘It is remarkable that that part of the range which is composed of basalt, is a fine open forest, whereas the basaltic hills of the large valley are covered with a dense scrub.’27 That stumped him.

  In the South Australian mallee in 1839, stumps bewildered Eyre:

  In some parts of the large plains we had crossed in the morning, I had observed traces of the remains of timber, of a larger growth than any now found in the same vicinity, and even in places where none at present exists. Can these p
lains of such very great extent, and now so open and exposed, have been once clothed with timber? and if so, by what cause, or process, have they been so completely denuded, as not to leave a single tree within a range of many miles? In my various wanderings in Australia, I have frequently met with very similar appearances; and somewhat analogous to these, are the singular little grassy openings, or plains, which are constantly met with in the midst of the densest Eucalyptus scrub . . . Forcing his way through dense, and apparently interminable scrub . . . the traveller suddenly emerges into an open plain, sprinkled over with a fine silky grass, varying from a few acres to many thousands in extent, but surrounded on all sides by the dreary scrub he has left. In these plains I have constantly traced the remains of decayed scrub—generally of a larger growth than that surrounding them—and occasionally appearing to have grown very densely together . . . The plains found interspersed among the dense scrubs may probably have been occasioned by fires, purposely or accidentally lighted by the natives in their wanderings, but I do not think the same explanation would apply to those richer plains where the timber has been of a large growth and the trees in all probability at some distance apart— here fires might burn down a few trees, but would not totally annihilate them over a whole district, extending for many miles in every direction.28

  Attempts today to explain these puzzles can be unsatisfying. Researchers write of soil boundaries, cracking clay, rain shadows, nutrient supply, frost and aspect. No doubt each applies somewhere, but none where trees grow now but not then. Other explanations—bushfire, salination, overgrazing—may sometimes be cogent, but rarely for sources so soon after newcomers came.

  Even particular trees might be curiously placed. Surprisingly often early Europeans crossed rivers and creeks via ‘fallen’ trees. Records mention twelve in Tasmania, at least seven in Western Australia, four in Victoria, three in New South Wales and one in Queensland, including over rivers like the Murray, Lachlan, Goulburn, Gordon and Tasmania’s Emu, ‘the widest and deepest river we had seen since leaving Circular Head’.29 It is hard to imagine a tree spanning those rivers now, or even a decent creek, yet in southwest Australia JC Bussell crossed several in one journey. Mary Gilmore said Aborigines dropped trees deliberately, by undermining their roots: she saw it done to cross Wollundry Lagoon at Wagga (NSW).30

  People may also have made straight tree lanes. Some led to initiation grounds. A ground near Mildura (Vic) was approached by a straight line of at least eight marked gums; another on the Macquarie by a ‘long straight avenue of trees, extended for about a mile, and these were carved on each side, with various devices’.31 On the Murray in 1844, a ‘natural avenue of gum-trees extends . . . two rows of noble trees growing at almost equal distances; the open grassy space between each row being at least 100 feet in width: so regular are the intervals between them, that it is almost difficult, at first sight, to persuade one’s self that they were not planted by the hand of man’.32 In Tasmania Henry Hellyer ‘ascended the most magnificent grass hill I have seen in this country, consisting of several level terraces, as if laid out by art, and crowned with a straight row of stately peppermint trees, beyond which there was not a tree for four miles along the grassy hills’.33

  Other curious plant stories have emerged since 1788: fire tolerant and fire sensitive plants side by side, plants needing one fire regime beside plants needing another, newcomers driving a carriage or painting a view through country where trees make this impossible now. Clear of settlement, there may be more trees today than in 1788.

  Bill Jackson calculated that 47 per cent of Tasmania should have been rainforest in 1788, but wasn’t. It was eucalypt forest, scrub, heath or grass, sometimes with burnt rainforest logs beneath. Jackson instanced sites where other plants had displaced rainforest thousands of years ago, and remained ever since. He noted that Tasmania had much less rainforest than New Zealand’s south island, a comparable climate, and concluded that deliberate burning best explained the difference.34 ‘The present distribution of floristic units in western Tasmania’, Rhys Jones agreed, ‘can be explained only in terms of both a high fire regime over a long period during the past, and the lifting of that pressure during the past hundred and fifty years.’35

  One aspect puzzled Jackson. ‘The boundaries between vegetation types at present seem remarkably stable . . . ’, he wrote, so it was ‘difficult to understand how such extensive areas of disclimax [unnatural] vegetation could arise in even [34,000 years—a 1999 estimate of how long people had been in Tasmania].’36 If other plant communities had moved so little since they displaced rainforest, Jackson was saying, how did they displace so much, even in so long? He was thinking of random fire. Community boundaries would indeed be unstable if Tasmanians had burnt randomly, but they did not. They burnt with purpose, as the stable boundaries show. In northern Tasmania RC Ellis found that on the same soil the ‘boundaries between rainforest, eucalypt forest and grassland were sharp and relatively stable’. Tasmanians selectively burnt rainforest back, then patrolled its edges.37

  Some boundaries were moved. In Tasmania much rainforest has a curious feature: giant eucalypts overtop it. Hellyer described this south of Emu Bay:

  This is a horrid place [to] be in, neither Sun nor Moon to be seen, no part of the sky, being completely darkened by dripping Evergreens consisting of Myrtle, Sassafras, Ferntrees, immensely tall White Gum and Stringy-bark trees from 200 to 300 feet high and heaps of those which have fallen lying rotting one over the other from 10 to 20 feet high.38

  Edward Curr, father of Victoria’s Edward Curr, echoed Hellyer:

  enormous Stringy Bark Trees many of them three hundred feet high and thirty feet in circumference near the roots exclude the rays of the Sun and in the gloom which their shade creates those trees flourish which affect darkness and humidity . . . sassafras, dogwood, pepper trees, musk trees . . . in some situations blackwood of the best quality . . . fungi, mosses, lichens, ferns.39

  Others noted the phenomenon,40 and it can still be seen (pictures 46–8). In Tasmania’s Mt Field National Park, opened in 1916 on land reportedly never logged, gullies and lower slopes support giant Swamp Gums, many scarred by fire. Under them is rainforest like Myrtle, Sassafras and Tree Fern, but no eucalypts. This is so too elsewhere in Tasmania: in the Styx, the Tarkine and the Blue Tier; and along the mainland’s east coast, for example in the Bunya Mountains (Qld) (picture 40) and the McPherson Range (Qld/NSW). On Cape York Christie Palmerston saw many examples: in the upper Daintree he cut

  through one patch of jungle . . . which has splendid green grass all along the top, but the sides are covered with dense jungle. Kept to this spur to the eastward for about four miles, and cut my road through four patches of dense jungle . . . The timber on the open ridges was principally gum, oak, bloodwood, and honeysuckle, and there was splendid soil on all the mountains.41

  All this is climax (natural) rainforest country. Eucalypt seedlings can’t grow in rainforest: there is no light. How did those giant eucalypts get there? Clearly, when they were young there was no rainforest. Without fire rainforest has returned, so fire once kept it back. No stray marauder can do that. It needs determined burning when conditions are right, and in rainforest that is not often. Eucalypts topping rainforest indicate land people once went to great trouble, working against the country, to clear and keep clear.42 Ancient eucalypts also stand above dense dry scrub with no young eucalypts. Such places have unnatural fire histories.43

  Other tree or scrub distributions also signal this. Kurrajongs like open land, which they got in 1788 because the tap root survives fire and the tree re-sprouts from base buds, but on reserves today, fire regenerators like wattle and casuarina are choking the ancient stands, and no seedlings survive. In semi-arid country two fires every five years are needed to clear Hopbush, but it became a major pasture menace after 1788.44 Fire made Tasmania’s dry Buttongrass plains, yet beside them may stand pines which fire kills, some 2000 years old.45 In Arnhem Land Blue Cypress needs mild fires
every 2–8 years. Fires more frequent or intense kill or damage the stand; fires less frequent let it choke with saplings. Lightning or casual burning could neither commence nor maintain such a fire regime, yet the pine stood in vast tracts in 1788, and stopping 1788 fire caused a ‘widespread crash’ in its population.46

  Even eucalypts, fire’s torchbearers, show that unnatural fire once shaped the land. In 1788 no-one lived on Kangaroo Island (SA) so it was dense forest, but adjacent mainland was open woodland. Without fire Tuart forest develops a very dense undergrowth, but early Europeans reported it ‘with plenty of grass’.47 Spotted Gums near Batemans Bay (NSW) seem pristine, but are not half the size of scattered stumps among them. A century ago this was dairy country, and in 1788 open forest. Without fire it would be rainforest. In north Queensland what looked like primal rainforest was a dairy farm only 40 years before.48 Other eucalypt forests have either a few giants scattered amid even-aged younger generations showing that once-open forest has thickened, or no old trees or stumps at all, indicating former grassland. Comparing forests in 1788, 1900, and 2000 would show a tree kaleidoscope, never the same.

  Bushfire rarely clears eucalypts: they regenerate from lignotubers or beards— branches sprouting from epicormic (sub-bark) buds under stress from drought, fire, poison or axe. Only repeated fire clears them, cool (ch 6) and frequent in dry country, hot and infrequent in wet.49 To convert eucalypts to grass people had to let fuel build up so fires could run, but burn often enough to kill seedlings, and maintain this over many generations until the old trees died. Burning most eucalypts every 2–4 years would in time make grassland, while burning a little less often would let some saplings survive and create open woodland. Both were common in 1788, some where trees and shrubs grow thickly now, others kept clear for so long that they have lost their seed stock and re-tree only by edge invasion, but re-tree they do.