The message
from robert contains these words:

A holding number is the county/parish/holding number (CPH) given to all
agricultural holdings registered with Defra or one of its agencies.

They are based on nine digits, county x2/parish x3/holding x4, eg
10/301/1111

Whilst they are not as important for involvement is subsidy schemes as
they used to be they are still useful as a tool for identifying the
location of farming businesses.

If you have a smallholding or land that could be classed as part of the
farmed environment you can apply for a CPH.

Many thanks. Interesting wording "classed as part of the farmed
environment"; would that mean it doesn't necessarily have to be a
commercial enterprise?

brian mitchell