Polypores are efficient decomposers, whose taxonomy and ecology are well-studied in Fennoscandia. In Finland, 37% of the 230 polypore species are classified as threatened or near threatened. The main reasons for the decline of polypores are the decrease in the area of natural forests, and the large-scale reduction in the amount of dead wood because of intensive forest management
Most polypores are to some extent specialized with regard to their growing substrates: prerequisites for occurrence can be connected with tree species, size, type, decay stage, microclimate, and biotic interactions. Furthermore, the size of the habitat patch, and the structure of the surrounding landscape have been shown to affect species occurrences.
Some species living in Finland:
Amylocystis lapponica - pursukääpä (FIN) - lappticka (SWE)
Vulnerable species restricted to large and fairly fresh spruce logs in rather moist microclimate.
Antrodiella citrinella - sitruunakääpä (FIN) - citronporing (SWE)
Vulnerable successor species of common species Fomitopsis pinicola . Found only on large and well-decayed spruce logs.
Cerrena unicolor - mossy tooth polypore (ENG) - pörrökääpä (FIN) - slingerticka (SWE)
Common species on birch logs, snags and branches.
Fomes fomentarius - tinder polypore (ENG) - taulakääpä (FIN) - fnöskticka (SWE)
Very common species growing on deciduous trees, mainly on birch.
Gloeophyllum protractum - yellow-red gill polypore (ENG) - liekokääpä (FIN) - tallstocksticka (SWE)
Near-threatened species restricted to rather large, barkless, hard but long decayed 'kelo' pine logs on sun-drenched places. Currently found only in northern Finland, but in the 19th century its distribution covered also southern Finland.
Gloeoporus taxicola - viinikääpä (FIN) - blodticka (SWE)
Quite rare species restricted to conifers.
Oligoporus rennyi - kuromakääpä (FIN) - skörporing (SWE)
Rather rare species growing on conifer logs.
Piptoporus betulinus - birch polypore (ENG) - pökkelökääpä (FIN) - björkticka (SWE)
Common species decaying birches.
Pycnoporus cinnabarinus - cinnabar red polypore (ENG) - punakääpä (FIN) - cinnoberticka (SWE)
Common species preferring deciduous logs in open and sun-drenched places.
Skeletocutis lilacina - liilakääpä (FIN) - lilaporing (SWE)
Very rare vulnerable species growing solely on spruce logs.