You might be surprised to know that the word ‘boundary’ has no special meaning in law. Generally speaking there are two ways in which it can be used; the Legal boundary and the Physical boundary.
The Legal boundary is an imaginary or invisible line which divides one owner's land from that of his neighbour. It is a line which has no thickness or width and is not usually shown with any precision either on the ground or in the legal documents which convey or transfer land. Nor is it shown on the Ordnance Survey mapping. If there is a dispute about a boundary line the exact line can only be determined by a Court or the Land Registry Adjudicator.
The Physical boundary is a tangible feature that can be seen; for example a hedge, wall or a fence. This may, coincidentally, also follow the invisible line of a Legal boundary. It can be difficult to record the precise position of the Physical boundary on a plan and will largely depend on the accuracy of the survey on which the plan is based. Even the most detailed surveys made with the most accurate and modern equipment have certain defined degrees of accuracy. The mapping based on the Ordnance Survey is no exception to this. A line shown on the Ordnance Survey map is only an indication that a feature existed in that position at the time the survey took place.
If it is clear from the legal documents or the title deeds that the Legal boundary runs along the line of a hedge, identifying this boundary line on the ground can prove difficult as a hedge is a living structure and, as such, can move if left to grow unchecked. It might take root where it touches the ground and either deviate from its original line or become very wide.
Approximately three quarters of land in England and Wales is registered at the Land Registry but even with registered land establishing the Legal boundary is not easy.
Because of the difficulties shown above the great majority of titles registered at the Land Registry show merely general boundaries. It is possible to apply to the Land Registry and ask them to determine the boundary. This is a request to the Land Registry asking them to show a definite boundary line. The Land Registry will require a very precise plan which meets the Land Registry's requirements showing the exact line of the boundary and will need to be consistent with the title deeds. It is also preferable to reach agreement with your neighbour about the line of the boundary but if an application is made to the Land Registry without the agreement of your neighbour the Land Registry will, if they feel you have a case, write to your neighbour giving them a chance to object.