Powerful Stuff.

David Jollands, 72, of Caythorpe, Lincolnshire, feared that the dreaded [leylandii] trees [that his neighbor had planted], which can grow to 80ft (25m), would tower over his garden – so he used his own gardening expertise to retaliate.

He started going for late-night walks to water the trees with his own urine. To his delight, the trees became brown and withered. Russell Brooks, his neighbour, also spotted the decline of his trees, so kept watch over his garden to catch the culprit on camcorder.

If Jollands had decided to urinate on his neighbour's compost heap, the outcome could have been so different; for many keen gardeners, urine is the secret ingredient for the perfect planting soil. The gesture may have been seen as a sign of friendship and an end to a boundary dispute that has lasted for eight years.

Urinating regularly, however, on a tree trunk or bark for almost a year creates too much salt, blocking conducting vessels and preventing water from keeping leaves green.

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