Hole in the tree

I came across this old rowan tree beside the stream when I was walking this afternoon. I have no idea how old it is but it looks as if it has been through quite a lot during its lifetime. At some time quite early in the tree's life, the trunk split into two and both sides grew on independently, although it does look as if the two halves met up again briefly, forming an oval hole, before returning to their independent ways. Above this temporary join, the left hand trunk has a hollow in it where the heart wood looks quite rotten, yet the growth above looks perfectly healthy. it could live in for quite a few years yet.
Later in my walk, on a piece of rough moorland, I stumbled across (quite literally) a recumbent wooden electricity pole. At least ten years ago, the poles were replaced and the old ones taken away, except this one. Now, it is just lying there, slowly sinking into the boggy ground. This dead piece of wood was quite a contrast to the vibrant old rowan I had seen earlier.