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In March 2020, Joel was invited to present to the Yankalilla & District Historical Society on our research into how the landscape of the Fleurieu has changed over the last few centuries. Below is an edited version of the talk. If you’re interested in knowing more, we can also send you some links to interesting historical images from the colonial period. Any errors are our own – let us know if you have any questions or comments.
In 2012, my wife Sophie and I, with our children Asher and Annika purchased Yarnauwi, just outside of Second Valley. Our property is just under 50 acres, running between South Road and the Wirrina golf course, and over the last seven years with the generous support of our friends, neighbours and family we’ve worked to regenerate this patch of the landscape.
Our property is intended to remain at least partly agricultural. We’re not seeking to return it to a prior state of imagined ecological perfection. As we’ve discovered through our research and through our experience of working with the land over the last seven years, too much has changed and is still changing to return what was there before colonisation.
Instead, we’re working to restore its health and function as a landscape, and to build its resilience in a changing climate. I’m neither an historian or a scientist, however we have spent a lot of time contemplating both history and science, and tonight I wanted to share with you some of what my wife Sophie and I have discovered in our process of working to regenerate Yarnauwi.
The vegetation associations of the Fleurieu Peninsula are constrained by their soils, rainfall, orientation and microclimate. I’ll be sharing what we’ve observed and learnt about broad patterns, but these of course, vary significantly. It’s worth remembering too that less than 10 percent of the original vegetation of the Fleurieu Peninsula still remains, and what does remain are in isolated fragments (Bickford 2001, p. 22).
In the highest rainfall areas, often with shallower, sandy soils, you can typically find Stringybark forest. Deep Creek, particularly along Tappanappa Road around Raywood Nursery, is a fine example of this with towering Eucalyptus obliqua, or messmate stringybark.
Stringybark is the dominant species, and as rainfall drops or soils become shallower, you typically see a shift towards Eucalyptus baxteri, often a smaller, more twisted stringybark, and eventually to pink gum. You can see this in places like Nixon Skinner Conservation Park at Myponga, where pink gum and stringybark are closely associated, and throughout Deep Creek. Likewise, in the Kalamunda native forest reserve between Yankalilla and Parawa, you can observe how on the same valley, north-facing slopes are dominated by pink gum, and cooler south-facing slopes are dominated by stringybark. Cup gum is also allied with these communities.
On the deep, fine-grained soils of the rolling country on the flanks of the highlands we find blue gum woodland – this is the landscape of Yarnauwi. The rainfall is typically lower than stringybark country, and topographically, the slopes are gentler and more rounded. The canopy of the blue gum woodland is open, contributing to the famous “park-like” appearance of many agricultural landscapes in the region, with an understory that is less dense than the stringybark forest. Ecologists have noted a relationship between stringybark, pink and cup gums, and likewise, blue gums are allied with manna and red gums. Likewise, sheoaks are typically more dominant, particularly where rock begins to surface, and red gums line the rivers and valley bottoms. Other familiar species are golden wattles, native cherries, sticky hop bush, yakkas. It is in this landscape that staple indigenous foods such as the yam daisy and kangaroo grass can dominate the understorey.
Throughout this landscape, red gums trace creeks, rivers and damp valleys, sometimes being joined by blackwoods and silver banksias. In structure and species, there are many similarities between the red and blue gum woodlands. Interestingly, as ecologists noted as early as the 1920s, where the blue gum woodland is cleared, it can often be colonised by red gum.
These associations are represented in the map above which suggests the natural vegetation associations of the Fleurieu. It’s worth noting that the blue gum woodlands form a coastal corridor, and due to their structure and the land management practices employed by Aboriginal people were the first and easiest areas to be cleared and colonised.
It was in this landscape that the Kaurna and Ramindjeri First Nations thrived for millennia, and overlaid their own land management. Through a deep understanding and meticulous observation, they observed and responded to seasonal changes to track, manage, harvest and conserve resources. The Dreaming story of Tjirbruke, gives an insight into the pre-colonial life of the Fleurieu. The story details a landscape criss-crossed with trade routes and seething with communication networks, a landscape known intimately and mapped by the resources available.
For the Kaurna, summer was a time to move towards the cooler climate of the coast, while during the cooler, wetter months, the Kaurna would migrate to the shelter of the hills and high country as the lowlands became floodplains and swamps. Through seasonal movement, the Kaurna could access a diverse, seasonal diet, while also avoiding the over exploitation of resources in particular locations (see James Tylor’s article on the Kaurna diet here.
A glimpse of the depth of Kaurna knowledge of their landscape is seen in the Kaurna seasonal calendar, represented by Scott Heyes (1999). Instead of seasons being fixed according to dates, as in the European calendar, the Kaurna calendar had 4-6 seasons, that would begin once a critical mass of environmental phenomena had been reached. Some may not occur at all in some years. In 1924, a ‘WGR’ gives a description that indicates the complexity of indigenous landscape knowledge in the region, echoed in the calendar. WGR recalls how during the gold rush, many white men on the Fleurieu left for the gold rush in Victoria. This saw a period when Aboriginal people assumed much of the work on settler properties throughout the region.
The youngsters went hunting and fishing with the natives, and learnt a lot of things unknown to the average white about birds, animals and fish. Shoals of mullet visited the coast at times. Dick [an Aboriginal worker] promised to let us know when they were coming. One night he roused me up, “Mullet come along, Master Willie. Put on clothes and come down beach.” Off we went, and sure enough there were great numbers passing along the sandy beach going south. Asked how he knew it, he pointed to a particular star in the south-east. “Yes, but how about this?” “Well, my father tell me.” It is remarkable that more than 60 years afterwards an aboriginal gave the same reply regarding the movements of another variety of fish.
It was this meticulous knowledge of the landscape and seasons that formed the basis for Kaurna land management, with fire a significant element of this. Through fire, the Kaurna and other First Nations could not only reduce fuel load, but also create a mosaic of different habitats, create forage for game, germinate fire dependent species or protect fire-sensitive species, protect special areas, open country for travel. This mosaic was overlaid onto the unique limitations and potentials of the soil and microclimates of the Fleurieu.
Early colonial depictions and descriptions of the western Fleurieu – usually the landscape we’ve identified as the blue gum woodland – describe an open landscape, often referred to colonist’s as reminiscent of a “gentleman’s park”, with large, widely-spaced trees over grassland. Colonists were thrilled at the agricultural potential of this landscape and quickly took advantage of this. The landscape they moved into was not a natural landscape however, it was a landscape managed and maintained by the Kaurna. As Sophia Bickford writes, “the treed, but very open, nature of the grassy woodlands of the Fleurieu Peninsula first encountered by Europeans, were likely to be demonstrating one effect, at a point in time, of Aboriginal burning.” As ethnobotanist Philip Clarke describes in Discovering Aboriginal Plant Use (2014), the staple crops of this region were likely Yam Daisy (Microseris sp., Ngampa in Kaurna) and cumbungi (Typha sp.). It’s likely that these open landscapes were also maintained for the cultivation of yam daisies and staple grains such as kangaroo grass, as described extensively by Bruce Pascoe in Dark Emu (2014).
Aboriginal fire use was noted by colonists in 1837, “…the watchers on the deck beheld a fire on one of the hills, which seemed to spread from hill to hill with amazing speed….at the end of summer as this was, the natives had set fire to the long grass to enable them to more easily to obtain the animals and vermin on which a great part of their living depends” (in Bickford 2001, p. 26).
In early images of the Fleurieu, historian Bill Gammage writes,
“no undergrowth, and trees in clumps, implying fire about every three years to make grass. Foreground hills are burnt, but forest fringes distant dunes… William Light’s nearby View at Yankalillah (1836) shows similar sheoak and scrub, very open. Such places are good camping: sheltered, cool in summer, handy to sea and plain. They were burnt less often: Drooping Sheoak needs at least seven fire-free years to seed. So at least two fire regimes, and possibly others for the swamp and the hills, made this land. Much of the coastal plain was similarly open – “extensive treeless downs, contrasting strikingly in appearance from the woody country around” … George Angas painted a view west to the sea over the Carrickalinga ‘river’, showing “the singular manner in which the trees were dotted about in all directions.” His Entrance to the gorge at Yankalilla (1850) shows many trees small enough to be post-settlement, but foreground eucalypts and sheoak big and few, while hills are almost bare, as at Rapid Bay further south. Together these pictures show varied tree spacing, but country always more open than is natural. To make such variety, fire regimes could not be haphazard. Each was distinct, repeated, and integrated with neighbours to maintain a range of plant and animal habitats.” (Gammage 2011, p. 40-41)
When travelling south, Sturt recorded the Onkaparinga hills as “grassy, and clear of trees… On the other side of Mount Terrible the country is very scrubby for some miles, until, all at once, you burst upon the narrow, but beautiful valley of Myponga … covered with Orchideous plants of every colour, amidst a profusion of the richest vegetation.” Many orchids signify recent fire. Jane Franklin wrote that the land between Mt Lofty and Encounter Bay “was exceedingly pretty; in some parts not unlike an English park, grassy and lightly timbered, and quite free from scrub and underwood,” and Sturt remarked that it was “so open that the labour of felling and clearing is wholly unnecessary.” … To burn patterns so complex in terrain so varied needs intricate knowledge of plants and fire, visionary planning, and skill and patience greater than anything modern Australia has imagined.” (Gammage 2011, p. 43).
In 1859, there is a passing reference to a local landowner Mr. J. Allen being requested to “caution his native shepherd respecting lighting fires in the bush.” It’s possible to imagine that the shepherd may have been attempting to maintain cultural burning practices in a rapidly changing landscape.
Elsewhere, Gammage writes of a template for the management of coastal plains, that recurs throughout Australia and may also be applicable to the coastal cliffs and plains of the Fleurieu. Colonial observations from Tasmania to north Queensland noted how often the coast was kept open for up to 3-4 miles inland, used for travel, hunting, and fish lookouts (2011, p. 93-94).
When we consider the Kaurna name for the locality of our farm, Yarnauwingga – “bald water place” or “bald hills water hole”, this seems to be a clue to the cultural nature of the landscape. Wirrina’s plantings through the 1970s and 1980s demonstrate the capacity of the landscape to support forest, and our own plantings are thriving in the deep soils, suggesting that the “baldness” of the region was a result of land management for open grassland rather than the natural state of the landscape.
It’s worth noting that often these records are from the easily accessible country along the coastal band, as part of the mosaic of habitat types cultivated through fire. Sometimes in the background of historical images we can see that the highlands were likely more heavily wooded.
The first Europeans to colonise South Australia, made decisions based on their economic and cultural context and the knowledge and resources they had available. They came to an unfamiliar land and climate, a landscape known intimately and managed sustainably for millennia by Aboriginal people, and initiated profound changes. Landscape ecologist Sophia Bickford asserts that the impact of European settlers was such that the landscape and ecosystems that exist now are considered entirely new ecosystems, due to the loss of indigenous species, the introduction of new species and substantial changes to the function of the landscape (2001, p. 290).
By 1840, there was a small population of British subsistence farmers living in the region. They had immediate impact through widespread land-clearing and cultivation of the landscape, as well as a change of burning regimes. While Aboriginal burning patterns ended with European arrival, burning actually increased, with landscapes burnt every five years or less to open the country for farming and grazing. This would have rapidly eliminated fire sensitive species from many areas of the landscape.
Grain production was a significant driver for agricultural growth in the early days of colonisation, and colonists moved into the blue gum and red gum woodlands of the region (such as the lands of Anacotilla and Yarnauwi). Blue gums and red gums were considered to be indicators of soil fertility. The “lands” method was the accepted method of cultivation at the time, ploughing furrows oblique to the contour on all slopes, and this led to significant sheet and gully erosion. As noted in 1928, ploughing transformed the Bungala River from a “chain of ponds” into an erosive gully,
The Bungala has its source in Eaglehawk Gully, two miles to the eastward of Kemmis Hill. The first settlers found this river of later days, nothing but a chain of surface holes, over which a man could step very easily. The furrow of a plough was accountable in the first instance of the chasm, which now exists. Beneath the banks embedded therein, are the trunks of huge gum trees, which are being laid bare as the result of successive winter floods…
Meanwhile, pastoralists were also quick to move into the open woodlands and grasslands so carefully cultivated by the Kaurna. By 1842, colonists noted that all the palatable grasses had been grazed out. Official numbers for 1844 suggest almost 11,500 sheep in the region. By the 1890s, by which time the highlands had been surveyed, there were almost 37,000 sheep in the region. Throughout this country, graziers typically burnt the scrub every 3-5 years in an attempt to cultivate feed.
Timber collection occurred from settlement onwards, with the open woodlands of blue and red gum the first to be cleared for timber and fuel, or ring-barked to open more country for grazing. From the early 1840s, itinerant timber cutters moved into the stringybark forests of the highlands, setting up logging camps. By the 1860s, timber cutting licenses were the largest revenue stream for the Rapid Bay Council, with timber cut for construction and use in local mining ventures, such as the Talisker mine, as well as the construction of jetties through the region, the production of 16,000 railway sleepers for the Port Adelaide railway, and the export of timber telegraph poles around the colony. It’s thought that by the 1880s, all of the large timber in the forests of the Fleurieu had been cut, with the ongoing timber cutting moving on to small trees and secondary regrowth.
Around this time, the wattle bark harvesting industry began to grow, with wild harvest of the wattlebark moving into cultivation. Land was cleared through burning, sown with wattleseed, then burnt again to germinate the seed. This industry continued into the 1920s.
With the implementation of chemical fertilisers and trace elements in the 20th century, land clearing accelerated, with the same amount of land being cleared between the late 1940s to the mid-1960s as had been cleared in all the years preceding. These cleared lands, much of which would have been former Stringybark forest, were typically sown to pasture and used to graze sheep. As beautiful as they are, it’s thought that the remaining stringybark forests are significantly different from their pre-colonial state. Observers in 1830 described the forests as relatively open, with trees of immense size, diameters typically over a metre wide, while the big trees are gone from the young, even-aged present day forests. The repeated burnings for grazing have likely eliminated many species that were once present.
Landscape historian Sophia Bickford writes, “The effects of widespread clearance … appear to be still in play, with species extinction and the invasion of non-native species continuing… Ongoing grazing disturbance is preventing overstorey regeneration. The effects of the almost-instantaneous imposition of agricultural and industrial technologies on the Fleurieu Peninsula landscape are still being played out. New ‘stable’ ecosystems have not yet been formed” (2001, p. 292).
This offers a reasonably grim picture for the environment of the Fleurieu, as American conservationist Aldo Leopold wrote, “One of the penalties of an ecological education is that one lives alone in a world of wounds.”
So what does this mean for our farm?
One of our intentions is for Yarnauwi to remain a productive landscape. However, it’s also a landscape that continues to experience erosion, and despite being saturated in winter, becomes bone-dry in summer. We’re working to make it more stable and resilient.
Our land has been long cleared, the soil has been transformed through decades of cultivation, spraying and grazing. Bringing back trees is one priority for us for habitat, shelter, and for managing water in the soil, and even attempting to rebuild local water cycles: rehydrate the landscape.
Bureau of Meteorology records show a steady downward trend for rainfall at Poolamacca (Second Valley) and Yankalilla from the 1880s. It’s possible that this trend is at least partly due to land-clearing. Writing about the settlement of Melbourne, Sophie Cunningham notes, “When the settlers arrived aggressive clearing began – so aggressive that the first peoples of the area noted a drop in rainfall caused by the loss of trees” (2019, p. 96). Scientists are increasingly acknowledging that there may be a sound foundation to the traditional wisdom that “forests attract rain”. Sheil and Murdiyarso describe forests as an “atmospheric moisture pump” that, when continuing unbroken from the coast, serve to draw moisture into dry continental interiors. In the context of the Fleurieu Peninsula, this suggests that under increased tree cover, there may have also been an increased rainfall. It’s also intriguing to note the presence of ancient manna gums on the hills that overlook our farm. Perhaps these gums are a lingering memory of a wetter time.
Some observers are increasingly aware of the role of local, ‘short-circuited’ or ‘closed’ water cycles, and their loss through land clearing. In contrast to the big scale of the long hydrologic cycle that sees water transition from land to oceans to clouds and back again, in areas with “well-established vegetation cover and … soil organic matter”, short water cycles cycle water and nutrients in highly localised environments and over short time spans. You can see this in the green circles underneath big gum trees in otherwise dry paddocks. Furthermore, the disruption and disappearance of short water cycles through deforestation hinders vegetation growth, and tends to increase the intensity of temperature fluctuations for a site between both day and night and from season to season. In short, trees capture and cycle moisture locally, and this results in an evening out of temperature extremes.
A farmer at Parawa once described to us how he recalled the winters of his childhood as being defined by constant mist and drizzle, a contrast from the present pattern of discrete dry period and rain events. It is interesting that one of the 1880s photos of the Anacotilla property depicts the hills to the south of our farm shrouded in low cloud. If such a climatic phenomenon occurred regularly, the interception of mist by vegetation could have served as another mechanism for hydrating the landscape. Writing of vegetation on the high points of the Mount Lofty Ranges, Peter Schwerdtfeger asserts that during drier spring and summer periods, the landscape “may frequently benefit” from “the capture of cloud droplets by tall trees… A wide range of indigenous and exotic plants owe their survival through the summer to this temporal augmentation of effective rainfall” (1976, p. 78). This pattern is also noted by Osborn and Adamson, who assert that “the persistence of cloud at the higher altitudes [of the Mount Lofty Ranges] must be taken into account … an appreciable amount of water which will not affect the annual rainfall must condense upon the vegetation…” (1924, p. 93).
With an understanding of the landscapes past form as a blue gum woodland, in many areas, it is these species that have thrived the most. The landscape has changed however, and now even some indigenous species no longer tolerate the changes. We look further afield and incorporate new species that will thrive and restore landscape function in a changing climate.
The colonial process of clearing the landscape unleashed a cascade of unforeseen consequences. Where the water was previously harvested in the soil and cycled through ecological processes, it now races along gullies that drain it from the landscape, leaving the soil desiccated. In his analysis of the dehydration of Australian floodplain landscapes, Cam Wilson also highlights how colonial land management practices often disrupted the relationship between waterways and groundwater (2011). The consequent erosion from deforestation and unchecked grazing not only drained surface water, but also interrupted groundwater flow, lowering it to the depth of the newly formed channels and beyond the reach of existing vegetation. In such circumstances, as the land dries out, vegetation undergoes succession as the existing wetland species are replaced by more drought-tolerant upland species.
Trees play an important part in managing water in the soil, but we also attempt small interventions using local materials such as through the construction of One Rock Dams, Zuni bowls and leaky weirs. These strategies are low-cost, use local materials and are easy to tweak and repair. They heal the landscape at its own pace and incrementally stabilise erosion and lift gully floors. As Bill Zeedyk says, erosion strategies like this “let the water do the work.”
The final element I’d like to share with you is that of fire. As we’ve described, fire has played a role in the Fleurieu for thousands of years. We are very aware that ours is a fire-prone landscape, and while we’re open to the idea of controlled burns, the density of people and assets in the area make this risky. We’ve designed our property with fire-breaks and fire-retardant species or species that reduce fuel loads in strategic areas.
We’re also investigating managed grazing as an approach to managing fuel load and increasing soil carbon. There is a precedent for this. Scientist Tim Flannery suggests that in the past Australian landscape, when megafauna roamed the continent, they consumed vast amounts of vegetation and manured the landscape, building soil carbon. Their demise saw an accumulation of fuel that may have triggered a period of catastrophic fires, and this may have catalysed Aboriginal fire management practices as a way of managing the landscape after megafauna. In short, in one sense, we’re hoping to use sheep as pretend diprotodons. That’s our next project!
In imagining our landscape not-so-long-ago, we are offered clues as to its future potential. If even a fraction of our guesswork is accurate, then the pre-colonial landscape of the Fleurieu Peninsula was most likely wetter, more effective in harvesting and managing water and offered a diverse, abundance of plant and animal foods. Over time, through careful observation and restoration of the landscape’s function we may be able to raise the gully floors and regenerate wetlands, woodlands and the soils that sustain us. For now though, we try to learn from the past, both the impact of colonisation and the possibilities of Indigenous land management. We plant trees, try to build soil and wait to see what happens next.
Adamson, R. S. and Osborne, T. G. B., 1924, The ecology of the eucalyptus forest of the Mount Lofty Ranges, (Trans. R. Soc. S. Aust. 48, 87-144)
Peter Andrews, 2006, Back from the Brink: How Australia’s landscape can be saved
Sophia Bickford, 2001, A Historical Perspective on Recent Landscape Transformation: Integrating paleoecological, documentary and contemporary evidence for former vegetation patterns and dynamics in the Fleurieu Peninsula, South Australia, PhD Thesis, University of Adelaide.
Philip Clarke, 2014, Discovering Aboriginal Plant Use
Sophie Cunningham, 2019, City of Trees
Bill Gammage, 2011, The Biggest Estate on Earth: How Aborigines Made Australia
Scott Heyes, 2009, The Kaurna Calendar: Seasons of the Adelaide Plains
Charles Massy, 2017, Call of the Reed Warbler: A New Agriculture, A New Earth
Bruce Pascoe, 2014, Dark Emu: Black Seeds – agriculture or accident?
James Tylor, 2019, The South Australian menu has always been seasonal
Cam Wilson, 2011, The Dehydration and Rehydration of the Australian landscape
1859, ‘District Councils – Rapid Bay’, The South Australian Advertiser, Thu 24 Feb 1859, p. 3
WGR, ‘Yankalilla Yarns: Further Comments and Reminiscences’, The Register, Sat 24 Mar 1924, p. 23
1928, ‘The Bungala’, The Victor Harbour Times and Encounter Bay and Lower Murray Pilot, Fri 6 July 1928, p. 4