A moss growing on or under a tree is an example of mutualism in the taiga biome. The moss protects the tree from wood-boring insects and the extreme heat of the sun, while the tree provides a protected living environment for the moss.
Aside from protecting trees, mosses also provide shelter to many living organisms, such as small worms, fungi and other microorganisms. Moss shares a symbiotic relationship with trees where both organisms benefit from each other by working together and depending on each other at some extent to thrive in their existing environment. The moss does not adversely affect its host tree, and the tree is neither damaged nor threatened by the presence of the moss.