Our estate is divided into 23,000 compartments, each of which has permanent, visible boundaries, and a unique identification code. The average size of a compartment is 19 ha. Each compartment is divided into one or more sub-compartments (also referred to as stands), which are numbered consecutively within the compartment.

Our inventory is conducted by specially-trained staff. We have approximately 30 inventory staff, located throughout the country. Survey intervals vary for an area, but each area is surveyed on average once every eight-ten years. They use the Ordnance Survey 1:10560 map as a basis for their survey and follow detailed guidelines for stand mapping to ensure consistency. The inventory process consists mainly of a ground survey, and it can be divided into a number of steps:

• Confirm compartment boundaries on the ground;
• Divide compartment into stands, depending on the age/species/growth rate of crop;
• Draw stand boundaries on field map;
• Describe stand; and
• Draw forest roads, right of ways, ESB lines, and other features on field map.

The following information is used to describe each stand:

• Location
• ID code
• Area (gross and net)
• Species
• Age
• Yield class
• Established spacing
• Land Use Type
• Site information - soil type, site fertility, elevation, exposure, drainage, windthrow hazard and machine workability

The basic crop and site information is recorded on a hand-held computer and downloaded to Coillte's Geographic Information System (GIS), where it is digitised and stored. The inventory data are available on the company's main computer network and reports, listings and maps can be generated.

There is occasionally a delay in transferring data onto the main computer network. For this reason it may appear, in the County Age Class Distribution section, that some counties may not have any post 2000 planting when in reality this may not be the case.