Fungi Causing Above-Ground Wood Decay in Structures in California


  • W. Wayne Wilco
  • Mark Dietz


Wood decay, structures, above-ground, basidiomycetes


Decay fungi were isolated and identified from decayed wood above-ground in structures in California. It was an opportunistic sample made available by a number of individuals dealing with decay problems throughout the state. An attempt was made to isolate as large a number of different decay fungi as possible from the limited sample material available. The total number of fungi involved in above-ground decay appeared to be small, and the list of fungi was almost identical with the list of fungi isolated from green lumber prior to use. This suggested the possibility that most of the fungi responsible for structure decay were present in the green lumber when the structure was built. Effects on distribution of decay by type of structure, location in structure, structure age, sub-structure construction and type of siding are reported, along with the frequency of structural defects and moisture problems promoting decay. Structures with slab-on-grade and stucco siding appeared to be the most vulnerable to decay. These data suggest an explanation for why California, with a low calculated Scheffer Climate Index, has decay problems of far greater severity than predicted by the Index.


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