4.This section defines a “high hedge” as being one which is formed wholly or mainly by a row of two or more trees or shrubs which exceed two metres in height and which forms a barrier to light.
5.Subsection (2), however, makes it clear that the density of the hedge is relevant. It provides that a hedge is not to be regarded as forming a barrier to light when the row of trees or shrubs contains gaps, which significantly reduce its overall effect as a barrier to light at heights of over two metres.
6.Subsection (3) makes it clear that the roots of the hedge are not relevant.
Commentary on Sections Meaning of “high hedge” Section 1 – Meaning of “high hedge”