Plants and cultural knowledge: how biodiversity sustains heritage

September marks National Biodiversity Month – a time to reflect on the richness of Australia’s environments and the responsibility we share in protecting them. At Extent Heritage, we recognise that biodiversity is never just ecological. It is cultural too.

In this article, we explore how heritage and biodiversity sustain each other, guided by the insights of ethnobotanist, anthropologist, and author Dr Philip Clarke.

Figure 1 Small redroot (Haemodorum brevicaule), for dye.

Figure 2 Ron Bonney and ethnobotanist, Philip A. Clarke, documenting Aboriginal plant use. If it is not possible to conduct a bush walk, then plants can sometimes be identified from books during interviews.

From museum collections to applied anthropology

Few people have spent as long examining the relationship between biodiversity and heritage as Philip Clarke. With a background in botany and zoology, he joined the South Australian Museum in 1982. It was there, working in the Aboriginal collections, that his interest shifted from plants and animals in the scientific sense to the cultural relationships surrounding them.

“I started out describing my work as ethnobotany, because it was mainly focused on plants,” he recalls. “But over time, I broadened into looking at Aboriginal relationships with the wider environment, particularly animals. Eventually, I realised that to understand these relationships properly, I needed anthropology as much as biology.”

Clarke went on to complete a PhD in social anthropology, while continuing to publish widely on Aboriginal plant knowledge. After three decades at the Museum, he left in 2011 to focus on applied work in heritage, native title, and land rights – the areas where his expertise now most often intersects with consultancies like Extent.

Plants as survival and resilience

In discussing the role of plants in Aboriginal knowledge systems, Clarke resists the idea of a simple list. Significance, he explains, is always relative to context. Some plants were everyday staples. Others were medicines or ceremonial markers. And some were what he calls “hard-time foods” – resources that were unpleasant, labour-intensive, or even toxic, but crucial for survival in times of scarcity.

One example is Nardoo (Marsilea drummondii), a small water fern found in the deserts of western New South Wales and Victoria. After rain, it produces spore cases that can remain in the mud for months or even years. Aboriginal people knew how to dig them up, crack them open, and prepare them as food. But they also knew the dangers.

Figure 3. Wangkangurru woman Linda Crombie collected the ngardu sporocarps (spore cases) from the nardoo water fern (Marsilea drummondii)

“It’s a very toxic plant,” Clarke explains. “Burke and Wills, the explorers, saw Aboriginal people eating Nardoo, but they didn’t realise it was mainly the aged Nardoo that was used, and even then, there was a complex process for getting the toxins out. Their deaths were contributed to by eating it incorrectly.”

Nardoo is just one example of the deep survival knowledge encoded in Aboriginal traditions. Foods that might be ignored in good times became lifesaving in harsh ones. These “hard-time foods” illustrate how biodiversity is never simply about species counts. It is about survival systems – and the cultural knowledge that makes those systems work.

Figure 4. Sacred lotus (red lily, Nelumbo nucifera), grows in deep billabongs throughout the Australian tropics.

Plants as cultural markers

Plants also serve as guides to seasonal change and cultural practice. In some regions, the flowering of daisies signals that swans are laying eggs or that mullet are running in rivers. Water lilies in the Top End carry dozens of different names depending on their part or life stage – tubers, stems, flowers, dead plants, sprouting leaves.

Clarke compares this to the well-known example of Inuit languages, where dozens of words for snow and ice encode survival knowledge. “It’s the same with plants,” he says. “Aboriginal people distinguished what mattered in the landscape, and those distinctions were built into the language.”

This holistic knowledge system extends beyond direct use. “Even plants without an obvious purpose are recognised as important because of the roles they play in supporting other species,” Clarke notes. “Everything is interconnected.”

Yam Daisy: a cultural touchstone

Among the many species Clarke has studied, the Yam Daisy (Microseris lanceolata), or Murnong, stands out as a plant whose story spans ecology, culture, and heritage.

A staple food across Victoria, parts of South Australia, and New South Wales, its finger-like tubers were widely harvested and eaten. European colonists often called it “wild dandelion,” a name that later fell out of use as “Yam Daisy” became more common.

“Today, Yam Daisy has become culturally significant again, particularly in Victoria, where communities are reintroducing it,” Clarke explains. “You can even buy it in nurseries now as a bush food plant.”

The plant has also been at the centre of heritage debates. In the 1990s, during the Hindmarsh Island dispute in South Australia, evidence was given that linked the flowering of the Yam Daisy with seasonal indicators such as the Seven Sisters in the night sky. Confusion over its shifting common names – “wild dandelion” versus “Yam Daisy” – became entangled in questions of women’s heritage knowledge.

“Even a plant as seemingly straightforward as a food source can become a battleground,” Clarke reflects. “That’s how central plants are to cultural identity.”

Figure 5. Yam Daisy or 'wild dandelion' (Microseris Lanceolata) tubers and foliage

Figure 6. Scented sundew (Drosera whittakeri) tuber, for pigment.

A message for National Biodiversity Month

Asked what message he would leave for audiences during National Biodiversity Month, Clarke is clear:

“Biodiversity and cultural diversity go hand in hand. We cannot really maintain one without the other.”

It is a reminder that heritage and environment cannot be separated. To sustain one, we must sustain both.

At Extent, we have been fortunate to collaborate with Dr. Philip Clarke on projects across Australia that bring biodiversity and heritage into dialogue, and these experiences continue to enrich our practice. Looking ahead, we are excited to keep building on this collaboration, learning from the depth of his knowledge and from the communities we serve together.

Dr Philip Clarke is an ethnobotanist and anthropologist based in Adelaide. He worked for three decades at the South Australian Museum before becoming an independent researcher and consultant. His books include Discovering Aboriginal Plant Use, Aboriginal Peoples and Birds (2023), and his forthcoming Aboriginal Peoples and Terrestrial Invertebrates (2026).

Figure 7. Dr. Philip A. Clarke