A British Hedgerow

Most hedgerows count their birthdays in centuries but naturalists have evolved a fairly simple method of working out the approximate age of a hedgerow. You measure out and mark thirty paces along it and then retrace your steps and count the number of woody plants growing along its length. Each one of these is the equivalent of a century. This may sound improbable, but it is based on some sound detective work by naturalists. ... We found over ten different kinds, which meant that, when this hedgerow had been laid down, the Tower of London and Westminster Abbey had still to be built.