Relationships between Trees and Fungi

Fungi can attack living trees as well as dead wood. While some species - notably the so-called 'brackets' and the stump-rotting gilled fungi - play an important role in turning dead trees into humus that can be reused by living plants, great damage is done to forests by fungal species that attack healthy trees. Parasitic fungi, such as this Fistulina hepatica, enter where the bark of the tree has been damaged.

Some fungi - notably the Amanitaceae, Boletaceae and Russulaceae - set up what are termed 'mycorhizal relationships' with trees. This means the fungus and the tree root system co-operate, exchanging nutrients so that each benefits from the presence of the other.

This Amanita muscaria has a mycorhizal relationship with a pine tree.

Honey fungus, Armillaria mellea (shown here growing on an oak tree) attacks living trees and those that have recently died or been felled.

As stumps decay, a succession of fungus species will appear until all useful nutrients have been extracted from the timber.