One of the most valuable biodiversity actionsBurning forest intentionally might sound like a very extreme action at a time when climate change increases the likelihood of natural, unplanned forest fires due to the carbon dioxide in the atmosphere. Thus controlled burning considerations need to balance between climate change mitigation, as forests absorb carbon, and biodiversity preservation, as burned forest provides an invaluable habitat for many threatened species.
This means that the areas for controlled burning are identified carefully: not any place is ideal to have the positive biodiversity impact. For instance, Brattforsheden in Sweden is one of the areas where Stora Enso conducted controlled burning in 2023. It is a dune field that has historically been characterized by recurring fires. Today the area is largely forested and a home for a wide range of flora and fauna that benefit from sand and fire in different ways.
“The areas that we select for controlled burning are environments that have been prone to forest fires before human intervention. Therefore, they benefit from and even require forest fires to retain their nature values. This way, we are able to also promote habitats for three of the species that we have selected to protect: the smoke-dancing fly ( Hormopeza obliterate), long-horned beetle ( Tragosoma depsarium), and a flower called “Lady of the Snows” ( Pulsatilla vernalis) that all thrive in burned forests,” tells Andreas Öster, Nature Conservation Specialist, Stora Enso Forest Sweden.
The three pillars of successful controlled burnings: safety, safety, safetyIn the Nordics, forest fires have decreased in the past century thanks to efficient infrastructure to extinguish fires and safeguard lives and infrastructure. Since controlled burning remains one of the most valuable ways to enhance biodiversity in a forest, it goes without saying that safety is of utmost importance.
“This is why controlled burnings are exactly that: controlled. The biggest danger is for the fire to spread uncontrollably, which is why – even if it may sound strange – the best time to do it is during very dry periods. This way, we can ensure that enough ground fuels – such as moss, lichen, dry grass, roots, needles, and branches – burn well and won’t later set on fire on their own, which makes the whole operation safer in the long run. To prevent the fire from spreading, the borders are watered well beforehand, and it’s important to choose a day when there’s stable wind and the air is humid enough,” Öster explains.
During the burning, there is always a well-trained team of fire operations present as well as a helicopter equipped with a water-carrier. Afterwards, personnel remains on-site until there is no smoke for two days. Nowadays, drones with infrared cameras have been a true game-changer for detecting smoldering fires.
The burnings in 2023 were conducted together with the Swedish Forest Agency and the County Administrative Board.