Sparse forests when fire shaped the landscape

In the past, fires would occur in many areas every 40 to 50 years. This had a profound impact on forest development and the flora and fauna that lived there. Through evolution, species "adapted" to the fires, and some even became reliant on them for survival. For example, there are insects that meet at fires to mate and lichens that can only thrive on charred wood.

There are also many species that are not entirely dependent on fires but benefit from them. Many of these species prefer open and sunny environments, which emerge after a fire sweeps through. Additionally, numerous plants appreciate when the mosses and lichens covering the ground burn away, allowing their seeds to germinate in the exposed soil.

Generally speaking, many fire-adapted species are not highly competitive and struggle to assert themselves among other species. However, after a fire, they get the opportunity to thrive and expand.

Good for pines – spruces died

Fires determined which tree species dominated our forests. Spruces rarely survive fires and thus seldom lived long lives. Pines, on the other hand, are specialists at enduring fires, leading them to dominate landscapes. The forests were characterized by sparse stands of pines, where sturdy individuals bathed in sunlight with significant distances between neighbours. Some pines could live to be incredibly old.

There also used to be significantly more deciduous trees than there are today, as these species regenerate easily after a fire.

Of course, there were also John Bauer-style forests, but these covered only small areas that had escaped fires for long enough to develop into such environments. Typically, young spruces would begin to take root and grow in the shade beneath the pines, but then the next fire would come and destroy them—starting the cycle anew.

Radical change in the late 19th century

Fires shaped the forests for thousands of years, creating thriving conditions for species that prefer bright, sunny environments. But in the late 19th century, humans began extinguishing forest fires effectively, radically altering the dynamics. Pines and deciduous trees lost their competitive advantages and drastically declined in number.

Spruces, however, benefited from the shift, along with other species that thrive in darker, wetter environments. The decreased frequency of fires also significantly impacted insects, birds, herbs, lichens, and mosses.

This marked a massive transition. Previously, forest grounds were mostly covered by lichens, but today, large areas are dominated by mosses, which prefer the shaded conditions in dense spruce forests.

Lot of life in dead trees

Another major difference today is that there is less dead wood in the forests. When fires swept through, many trees died, creating an abundance of dead wood that provided both food and habitats for flora and fauna.

"There is an astonishing amount of life in dead trees. They are incredibly important habitats." 

Particularly valuable are the trunks of old pines that have survived multiple fires but eventually succumbed. Over the years, as these pines were damaged by various fires, they self-impregnated with tar-like substances, making their wood highly resistant. The damage also slowed the growth of the trees, causing the wood to become very dense and tough. As a result, these dead pines can remain intact and provide ecological benefits for hundreds of years before they finally decompose.

Burning benefits species

Nowadays there is a lack of such old, dead pines. There is also a shortage of forests that arise after fires. This makes it tough for fire-dependent species. You could say that these species have lived in a sort of "subsistence existence" for the past 150 years.

To address this, SCA regularly works with prescribed forest burnings. In this process, we burn forests under controlled conditions to create habitats that fire-dependent species need. It also creates forests resembling those of the past: sparse, bright pine forests with quite a few deciduous trees, but not so much spruce.

In many areas, burning is the best management measure SCA can implement, as it is the most natural intervention we can make. Fire has shaped our forests since ancient times.