Katie Paterson’s IHME Helsinki 2021 commission was born out of the artist’s fundamental drive to create artwork that heightens awareness of the sixth extinction. To Burn, Forest, Fire explores the scent of the first and last forests through the creation of bespoke incense sticks. The artist collaborated with scientists to define and characterise these forests, the scents of which have been made into incense and burned across a variety of sites around the city of Helsinki, and beyond.

The Earth’s first forest grew in modern-day Cairo, New York State, 385 million years ago. It was discovered through fossilised root systems containing three types of ancient plant species, including Archaeopteris, which had well-developed roots, a large trunk and branches with leaves. What would it have been like, this forest? A shady place of greens and browns, certainly, but probably with little other colour – the evolution of flowers was still a long way into the future. A quiet place, probably – not quite bereft of animal life, for small millipedes, mites, springtails, crustaceans and other invertebrates had already moved onto land with the plants.

The second incense stick recreates the scent of a living forest biome that is acutely endangered, and has become an emblem of the ongoing ecological crisis: the Amazon Rainforest. Home to about 10% of all biological species on Earth, the Amazon has thus far been deforested by about 20%. Reduced rainfall due to climate change is driving a feedback loop in the Amazon involving wildfires and the local hydrological cycle, which could convert much of the rainforest to savanna by the end of this century.

In To Burn, Forest, Fire, the Amazon is represented by a single locality: the Tiputini Biodiversity Station in the Yasuní Biosphere Reserve in Ecuador. The Tiputini station provides the IHME commission a discrete look into the Amazon which, at least for the time being, remains a vast and varied rainforest biome.

These past and future environments have been translated into incense, in collaboration with Japanese perfumers and incense makers Shoyeido. The scent of the first forest is guided by basic, identifiable elements of the Devonian environment: the soil, the plants and their closest modern analogues such as lycopsids and liverworts, and the swampy aroma of anaerobic decay.

By comparison, the scent of the last forest can be developed from a much wider body of information. Dr Ana María Yáñez Serrano’s research on airborne volatile organic compounds (VOC’s) describe the chemical constituents of the modern rainforest scents: the isoprene emitted by almost all plants, but also an assemblage of dozens of monoterpenes and sesquiterpenes unique to the Amazon. This chemical foundation is complemented by careful descriptions made by the staff and local groups at the Tiputini Biodiversity Station in Ecuador. Field observations in the vicinity of the station in early 2021 recorded a stunning array of scents, from the alcoholic fizz of guava trees to the fresh peanut-like aroma of the Earth, all combining to a unique sweet and bitter fragrance of the modern Amazon.

To pinpoint the first and last forests, the project turned to geology, and the scientific knowledge about the long-term evolution of life on Earth. A team of advising geologists included Prof. Jan Zalasiewicz (University of Leicester, UK) and Dr J. Sakari Salonen (University of Helsinki), with further comments and advice from Prof. David George Haskell (University of Sewanee, USA), Dr Chris Berry (University of Cardi, UK) and Prof. Sarah Gabbott (University of Leicester, UK). In addition, collaborators include ecologists and biologists specialised in modern-day, threatened rainforest biomes: Dr Ana María Yáñez Serrano (CREAF, Ecological and Forestry Applications Research Centre, Spain) and David Romo Vallejo (Tiputini Biodiversity Station, Ecuador).