Anyone know what this funky happening is?  (The black stuff not the fungus growth).

Not sure, but possible Phytophthora spp (watermold) infection, with the black exudation being the tree's natural reaction to the invasion. The turkey tail fungus is saprophytic (invades dead wood) and probably the more advanced stage of this disorder.  Is there sprinkler water continuously wetting the tree trunk?  If so that could be a causal factor. The nails into the tree trunk can contribute to pathogen invasion.   

13 hours ago, drtreelove said:

Not sure, but possible Phytophthora spp (watermold) infection, with the black exudation being the tree's natural reaction to the invasion. The turkey tail fungus is saprophytic (invades dead wood) and probably the more advanced stage of this disorder.  Is there sprinkler water continuously wetting the tree trunk?  If so that could be a causal factor. The nails into the tree trunk can contribute to pathogen invasion.   

 

Thanks for that, you were pretty close.

Mrs sent the pics to a local gardening company who said it was a reaction to the nails in the supports and to remove them and clean it off then spray it and it should be all good.
So pathogen from nails it was.

Local gardening company? Spray with what?  ..should all be good? That's optimistic, but I  have my doubts. Extensive wood decay like this cannot be reversed, tree tissue does not regenerate like in animals, it only closes over with callus tissue in some cases.  An external spray will not likely reach the internal advancing mycelium of the wood decay fungus. Extensive damage has been done and attention should be on potential risk from structural failure if the tree is large and near potential high value targets.