Hedgerows

[Kenelm Philip]

	'Hooper's Rule' for the age of hedgerows is discussed in Chapter
9 of Oliver Rackham's fascinating book 'The History of the Countryside'.
There is no mathematical subtlety involved here--the rule was derived
observationally from a study of hedges of known age (75 to 1100 years).
There are some exceptions, which Rackham lists as the elm exception, the
Grantchester exception, and the Neroche exception--so the rule needs to
be applied with caution.

							Ken Philip
fnkwp at uaf.edu