Beach fungi

[Treeation]

Yeah looks like saprophytic...would be worth having a tap with a sounding mallet and a poke with a screwdriver to assess the extent of decay, also have a good look on the other butress roots for more decay. Crown stills seems healthy (assuming the photo was taken in winter)

[daltontrees]

Would it be fair to say that the area in the foreground of the 2nd photo has been excavated for a landscaped garden? If so, there's the cause. Fungus looks saprpphytic.