William - Beautiful photos thank you for sharing .. With out a sample my best guess is that it's a fruiting body of a wood decay basidiomycetes (mainly grows on wood, sometimes it can also be found growing on soil). This fungus rapidly degrades cellulose and lignin (which give strength of the wood) and as a result wood is degraded. It does not produce any mycotoxin and not harmful to humans (but not edible). It produces abundant basidiospores (lower surface of the fruiting body), as a result some people may get allergy if exposed to large numbers of spores. Again, it's a harmless fungus but can rapidly degrade the wood.


Don't know that you wanted to really know but got my two cents in anyway.

Best Regards
Greg D. Dames
National ThermoGraphic Inspections
Pacific Mold Assessment