Finns love a good forest fire…

The Finnish government and commercial forest owners have started to arrange controlled burning of forests to improve regeneration and forest diversity.

Controlled burning is nothing new here – it has been going on for years but new scientific studies have revealed that controlled burning and careful regeneration are important ways to care properly for forests.

Climate change is also causing more wild fires in forests because draught and hotter weather with more storms makes the forests more likely to catch fire and burn more fiercely when struck by lightening. These forests need replanting as soon as possible, which is probably not the case in the USA, where even the president appears to be clueless about forest management – he has suggested that Finns avoid forest wild fires by raking the undergrowth!

Commercial farmers in South America, in Asia and in Africa are unfortunately burning rain and tropical forests deliberately for grazing land, rubber and palm oil plantations and other agricultural activities. They may be gaining some extra cash from this activity but this burins of such critical assets is a foolish way to damage the globe… The loss of rain forests and tropical forests endanger our world. On the other hand, the controlled burning of small areas of forests for regeneration and diversity takes us in the opposite and good direction.

During the past summer, Tornator, a forest investment company with StoraEnso as the major shareholder, carried out a total of 5 different controlled burning sites in eastern Finland totalling 50 hectares. This has been repeated for almost a decade in the same area.

In forest management, logging residues, waste trees and parts of the ground humus layer are burned from the felling area before new saplings are planted.

The aim is to improve forest growth and diversity in commercial forests. Incineration produces alkaline ash, which reduces the acidity of the soil. The nutrients in the ash from wood residues and the humus layer are utilised easier and faster by the new tree generation. Burning also curbs the spread of pests.

Controlled burning mimics the natural burning of our forests. During the millennia, Finnish forests have burned naturally about once in a hundred years, but current effective fire fighting have effectively stopped wild fires in commercial forests. The living conditions of fire-dependent species such as beetles, lichens and fungi have thus deteriorated significantly. 

In most controlled burnings, a few trees are normally left to burn in a special area – (see the Special Burn video below). This can create important habitats for fire-dependent species, but it is challenging to find a suitable site.

A successful controlled burn needs a sufficient supply of water, and it also needs to be near a road with easy access for fire-fighting equipment – a road automatically serves as a good fire-defining fire alley – and you also need a sufficient amount of waste-wood residue and humus for good results.

The harvesting wood from the forest needs planning once an area has been chosen for controlled burning, so that logging residues are spread evenly over wide area for burning. 

A fire passage free of logging residues is left at the edges of the burn site. To the extent that the site is not bounded by a water protection zone or road, an excavator must expose mineral soil 2-3 meters wide to stop the fire from spreading. Water hoses are needed if the fire escapes, but skilled burning personnel are generally sufficient to prevent the spread of fire.

As a rule, burning is carried out in the spring following the winter harvest. Prior to implementation, the area will be carefully inspected for bird nests that will be mapped, marked and protected. 

Depending on the site, the controlled burning is carried out in parts or all at once, according to a plan made in advance. Due to occupational safety and the spread of sparks, large piles of wood are often burned in blocks, making the fire easier to control and predict. 

After the incineration, it is the turn of the post-guard, which lasts from two days to several weeks, depending on the circumstances. The timing of burning before the rainy season significantly reduces the need for post-guarding, as does watering the site with fire hoses after the burn.

Photos: The Finnish Forest Center or in Finnish “Metsäkeskus”! The people there were very helpful in getting this article written. They even had some interesting videos at the following sites – unfortunately they are in Finnish but that will not be a problem for firebugs who read this!

Here are the videos:



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