They say money doesn't grow on trees.
But it certainly appears to do so on the mysterious coin-studded trunks dotted around the UK's woodland.
The strange phenomenon of gnarled old trees with coins embedded all over their bark has been spotted on trails from the Peak District to the Scottish Highlands.
The coins are usually knocked into felled tree trunks using stones by passers-by, who hope it will bring them good fortune.
These fascinating spectacles often have coins from centuries ago buried deep in their bark and warped by the passage of time.
The tradition of making offerings to deities at wishing trees dates back hundreds of years, but this combination of the man-made and the natural is far more rare.
It used to be believed that divine spirits lived in trees, and they were often festooned with sweets and gifts - as is still done today at Christmas.
The act is reminiscent of tossing money into ponds for good luck, or the trend for couples to attach 'love padlocks' to bridges and fences to symbolise lasting romance.
Some pubs, such as the Punch Bowl in Askham, Cumbria, have old beams with splits in them into which coins are forced for luck.
There are seven felled tree trunks with coins pushed into them in the picturesque village of Portmeirion, in Wales.
Meurig Jones, an estate manager at the tourist destination, told the BBC: 'We had no idea why it was being done when we first noticed the tree trunk was being filled with coins.
'I did some detective work and discovered that trees were sometimes used as "wishing trees" .
'In Britain it dates back to the 1700s - there is one tree in Scotland somewhere which apparently has a florin stuck into it.'
He said that a sick person could press a coin into a tree and their illness would go away.
'If someone then takes the coin out though, it's said they then become ill.'
'We haven't publicised it at all, it's just happened,' he added. 'It's quite amazing really.'
In Scotland, there is also a legend about a kissing tree. If a young man could drive a nail into a tree with one blow, he earned a kiss from his sweetheart.
Yoko Ono has used wishing trees in her artwork, and in 1877 Queen Victoria wrote about visiting an oak tree with coins stuck in it in the Highlands.