Fungus, coins and superstition

It was foggy in Perth, so for our Saturday walk we drove up to Comrie, where the forecast was better.

Walking up to the Deil's Cauldron we passed this fallen tree with many coins hammered in. I know this used to be a tradition with a few favoured trees, but more recently every fallen tree seems as likely to have coins as fungus. Is this a genuine superstition, do you think, or just a cultural meme like the padlocks? Either way, I have the uneasy feeling that rationality is on the retreat.

Further along our walk (see the extra) we glimpsed a dipper singing beautifully. It was too far away to photograph, but we listened for two or three minutes. I didn't know they were such strong singers; usually they seem to busy to say anything.