What are inventories?
All UK countries now have an ancient woodland inventory - a map-based record of the location and boundaries of ancient woods.
In England, Scotland and Wales these were created in the 1980s and early 1990s by the Nature Conservancy Council (now Natural England). They are now held and maintained by the statutory conservation agencies in each country - Scottish Natural Heritage in Scotland, the Countryside Council for Wales in Wales and Natural England in England.
In Northern Ireland, the Woodland Trust produced the inventory, which was launched in 2007 and can be accessed at www.backonthemap.org.uk
The inventories are all provisional. This means that woods may be added or removed from them, or their classification might change, if new evidence comes to light. Except in Northern Ireland, they do not include woods under 2 hectares (5 acres) in area. None of the inventories cover ancient wood pasture and parkland sites.
How do inventories help protect woods?
One of the key uses of ancient woodland inventories at the Woodland Trust is in fighting woods under threat cases.
Ancient woodland, land that has been continuously wooded since at least 1600, has some protection under planning guidance in some UK countries. This means we are better able to fight wood under threat cases where woods are classified as ancient woodland on such inventories.
The inventories also help us decide our priorities for action across the UK. We believe that action for biodiversity has the greatest chance of success in areas where habitats are concentrated. We were able to use the ancient woodland inventories to determine relative areas of ancient woodland concentrations in the UK.
These priority areas inform our lobbying work and also where we focus our site based action.
How are inventories created?
In each country, different sources were used to identify ancient woods:
In England and Wales: Ordnance Survey maps from the early 19th century were used as the baseline. Where possible, but not always, earlier maps and records, and the wood itself, were also studied to decide whether it was ancient.
In Scotland: The early Ordnance Survey maps were supplemented by the Roy military maps of 1750. This has led to an additional category of long-established woodland.
In Northern Ireland: The first edition Ordnance Survey maps were used as a baseline. Every wood was also subjected to detailed archive study and field survey to determine its antiquity. This inventory is also divided into ancient and long-established woods.