A barren pine forest becomes more diverse when it gets older. Old trees, as well as dead, dry standing snags and decaying tree trunks form habitats for whole communities of species that feed one another. Snags and rotten standing birches are suitable nesting places for birds. The nutrients of decaying trees return to the soil. The decomposers, such as polypores and micro-organisms, play an important role in forests.
The use of the forests is visible in the forest structure. There are traces of former tar-burning and logging activities in the terrain.