Damp & Mild
This is the latest fallen Beech in the valley, a huge tree. The reason for the coins well there are a few trees around covered in coins, one I know is near Ingleton, North Yorkshire. So someone (not me) has done this to start the trend we haven't put any in as yet.
There is another tree stump at Dry Bones with a few coins in - it is probably not noticed by most people that pass it.
Copper has been used to kill tree stumps for years - so it probably evolved into hammering coins into the stumps then people thought it was lucky to do and so you get a tree trunk filled with coins, the one at Ingleton is stunning.