Non-renewable Jokes

My two favourite anecdotes on this subject demonstrate the difference
between renewable and non-renewable resources. First the non-renewable:
The congregation of a small stone church (in England?) decided that the
stone which formed the step up to the front door had become two worn by its
years of use, and would have to be replaced. Unfortunately, there were hardly
any funds available for the replacement. Then someone came up with the bright
idea that the replacement could be postponed for many years by simply turning
the block of stone over.
They discovered that their great-grandparents had beaten them to it.
Now the renewable:
An entomologist at New College, Oxford ("New" because its only a few
centuries old), discovered beetles infesting the oak beams supporting the roof
of the Great Hall. It was fairly urgent that these be replaced before the roof
collapsed-but anyone who has looked at the price of oak lately can tell more...