Evidence of a relationship between the occurrence of wounds on balsam fir and attack by Stereum Sanguinolentum has drawn attention to the possibility that infection and subsequent establishment of this fungus may be influenced by the severity of the injuries, particularly when they result in the death of the host. The observations presented in this paper demonstrate the existence of such a relationship and to show how the condition of the host as a result of injuries may determine the kind and distribution of colonizing fungi.