I was in London today for a seminar, hosted the Arboricultual Association and presented by Barrell Tree Consultancy, regarding British Standard 5837:2012 and how to manage trees effectively on construction sites, in the lovely area of Bloomsbury Square. Characteristically, I was there very early, so had a chance to look around the trees in the garden square. Many of the trees were London plane, of which most were very mature. One drew my attention in particular, as it had very pronounced ‘bottle butt’. Lo-and-behold, there were old sporophores of what is probably Ganoderma australe, on two sides of the butt. Without question, this has at least partially facilitated in the creation of the bottle butt, as the fungus induces a white rot that de-lignifies the wood, making it soft. As a result, reaction growth is laid down, creating the bottle butt formation.