Polypores hide inside trees until it is time to reproduce
Polypores are Basidiomycota fungi, the mycelium of which often grows inside tree trunks, hidden from prying eyes. The mycelium decomposes dead or dying wood and slowly recycles the nutrients within, making them available to other plants. From time to time, the mycelium will grow a fruiting body on the surface of the trunk, which is the fungus’s reproductive structure. Its purpose is to produce spores that are released into the air and spread by winds to new growth sites.
The polypores found on Ruissalo include chicken of the wood, oak mazegill, beefsteak fungus and robust bracket, all of which decompose English oak and are thus quite common on the island. Chicken of the wood (Laetiporus sulphureus) is a bright yellow, impressive polypore, which often penetrates into oaks via splits in branches. Chicken of the wood is annual, meaning that it grows new fruiting bodies on the side of the tree every year. Over time, the fungus’s decomposing hollows out the tree trunk. Oak mazegill (Daedalea quercina) is a perennial polypore that grows in oak stumps, on the trunks of fallen trees and in the dead branches of still living trees. The species is easy to identify by its maze-like gills. Beefsteak fungus (Fistulina hepatica) is a big, soft, dark red polypore with a slimy or leathery surface. It is an annual fungus that usually grows at the base of the oak tree. Robust bracket (Phellinus robustus) is a perennial polypore that grows on oak trees. Its large, up to 15 cm thick, hard and bumpy fruiting body has a cinnamon-brown underside. Polypores play a key role in increasing the biodiversity of the forest, as the decaying wood that they produce serves as homes and food for a wide range of creatures.
