Burnt Grass Reveals Ancient ‘Magic’ Rituals in an Australian Cave

When you step into Cloggs Cave in the high country of Victoria, you might not expect to find remnants of a fire that burned thousands of years ago. Yet, tucked in the silty floor are tiny glass‑like particles called phytoliths, and a good number of them are blackened, as if they’d just come from a smouldering hearth.

Researchers from Australian National University, Monash University and a French partner have now taken a fresh look at these microscopic clues. Their paper in Frontiers in Environmental Archaeology argues that the burnt grass wasn’t accidental at all – it was deliberately gathered, carried into the darkness and set alight as part of what the GunaiKurnai people called “magic” rituals.

The story starts with the cave’s long‑known history. Archaeologists first rediscovered Cloggs Cave in the 1970s, but it was only after the GunaiKurnai Land and Waters Aboriginal Corporation returned in 2019 that a deeper, collaborative investigation began. The partnership opened the door to studying the cave’s archaeobotanical record – essentially, the plant fingerprints left behind.

From a series of pits the team excavated, they pulled out thousands of phytoliths. Unlike pollen, which can travel far on wind or insects, phytoliths tend to stay put where the plant decays. That makes them perfect forensic evidence of what was actually placed in the cave. About 18 % of the 29 plant types identified were burnt or partially melted, and many of those came from the leaves and flower stems of grasses.

“No plants grow inside the cave because there’s no light,” explains Elle Grono, the study’s first author. “So the only way these phytoliths got there was on human shoulders – or perhaps on the fur of nocturnal animals like possums.” Yet the pattern of the ash layers – 73 distinct, thin blankets dating from roughly 4,000 to 1,600 years ago – points to repeated, intentional deposits rather than random animal activity.

Adding intrigue, a standing stone about 28 cm tall was unearthed in one of the ash‑rich layers. The stone, likely set upright by the GunaiKurnai around 2,000 years ago, may have acted as a focal point for the ceremonies. Near it, researchers found wooden sticks with smeared animal fat, another possible ritual implement.

GunaiKurnai elders have long spoken of caves as places of healing, cursing and other “magic” work. The distribution of the burnt grass aligns with those oral histories, suggesting that ash was used not only for its symbolic potency but perhaps also to mark a pathway for spirits or to demarcate sacred space.

Anna Florin, an archaeologist at ANU who was not involved in the study, praised the interdisciplinary approach. “It’s a great example of marrying hard‑science phytolith analysis with Indigenous cultural knowledge to reconstruct a practice that spanned many millennia,” she said.

While the authors acknowledge that any interpretation of prehistoric ritual is provisional, the convergence of phytolith data, ash stratigraphy and GunaiKurnai oral tradition makes a persuasive case. It also highlights how under‑used archaeobotany can be a window into the spiritual lives of ancient peoples, not just their diets.

In the end, the burnt grass of Cloggs Cave does more than show us that fire once crackled there; it whispers of gatherings, chants, and perhaps a shared belief that the scent of smouldering herbs could bridge the human and the unseen.