We also examine wood fungus communities in primeval forest. The methodology includes somatic incompatibility tests and studies of DNA variation. It has been shown that the Gremmeniella abietina that attacks contorta pine is indigenous and is identical to the Gremmeniella that infects seedlings under the snow. This race is northern and is clearly genetically different from the southern race of Gremmeniella that attacks pine forests. The results from H. annosum and S. bovinus have shown that populations often consist of relatively dense populations of small individuals while older populations are made up of relatively few large individuals.
Many fungi exist as subspecies associated with specific tree species.
Important factors in the development of wood decay fungal communities are parasitism and competition between mycelia from different species. In population biology we study the distribution and size of individual fungal mycelia among different species. These factors help us understand what is important for the spread and survival of fungi.