It grows on the side of various species of tree, which it infects through broken bark, causing rot. The species typically continues to live on trees long after they have died, changing from a parasiteto a decomposer.
Though inedible,F. fomentariushas traditionally seen use as the main ingredient of amadou , a material used primarily as tinder, but also used to make clothing and other items. The 5,000-year-old Otzi the iceman carried four pieces ofF. fomentarius, concluded to be for use as tinder. It also has medicinal and other uses.