Ancient Woodland Inventory Update Project

The Ancient Woodland Inventory is a publicly-accessible dataset holding information on locations and types of Ancient Woodland – areas which have been continuously wooded since the 1600s. As an irreplaceable habitat of great importance for biodiversity, the inventory is a vital resource to inform conservation of these areas. 

The ERIC team are currently involved with a project updating the Ancient Woodland Inventory – find out more about our project below, including how you can get involved!

Ancient Woodland

Ancient Woodland is a highly valuable, irreplaceable habitat, defined as any continuously wooded area since 1600. Due to its complex soils and ecosystem, it is of great importance for many species, and may also hold cultural and historical value. Ancient woodlands can be categorised into two types – Ancient Semi-Natural Woodland (ASNW), and Plantation on an Ancient Woodland Site (PAWS). ASNW sites developed naturally, though are likely to have been used and managed by humans. PAWS have been felled and replanted, but are still important as they retain the rich complex soils and communities of an ancient woodland site.

Updating the Inventory

The Ancient Woodland Inventory holds data on all currently designated ancient woodland sites, and is a vital dataset which is used to inform conservation decisions and management. Currently, there are over 1300 ancient woodlands designated in the North East.

The original inventory was completed in the 1980-1990s, and was later digitised to be used as seen today. New technology, digital maps, and modern aerial imagery allow us to update the inventory with further precision and an updated methodology. Originally the inventory focussed on areas of 2 hectares or more. Within the update, we are identifying areas greater than 0.25ha in size, allowing for opportunities to identify areas of fragmented ancient woodland.

Ancient Wood Pasture and Parkland

Within the update, we are also capturing areas of ancient wood pasture and parkland. These areas are identified as a priority habitat, often holding multiple generations of trees and shrubs, and will have been heavily managed – usually by grazing.

There is currently a provisional dataset of Wood Pasture and Parkland published by Natural England, but this dataset does not include evidence for ancientness.

Our Methodology

To complete the inventory update, we are following a standardised national methodology with a phased work flow.Image detailing a flowchart of the phased workflow, reading Phase 1: identify areas of long-standing woodland. Phase 2: Categorise against the current ancient woodland inventory. Phase 3: Gather and assign evidence for ancient woodland status. Phase 4: Categorise ancient woodland status.

Phase 1 covers an initial comparison of the first ordnance survey maps from the 1850s with current aerial imagery to identify areas of long-standing woodland. These woodland parcels are then carried forward to Phases 2 and 3 to be compared with the current inventory and gather further documentary evidence. Such evidence includes older maps and literature from the 17 and 1800s, other ordnance survey maps to confirm continuity of woodland between 1850-2000, and field evidence. We will be using ancient woodland indicator species and historical features to infer ancientness in a site. Pre-submitted biological records will be used alongside some field surveys completed by our team.

During Phase 4 we will refine our woodland boundaries and assign a ‘type’ of ancient woodland (ASNW or PAWS) for areas with enough evidence to infer ancientness. Our evidence base and final dataset will then be published alongside a report, and added to the updated inventory.

Our Progress

Last updated 22/08/2023

We have currently finished most desk-based work for Northumberland, and have been able to complete a few field visits over the spring and summer to begin identifying indicator species. We are currently looking for and contacting landowners to gain permissions for future field visits, and have begun work on Phases 1-3 for Durham and the Tees Valley, which we are hoping to complete in the next couple of months.

Get Involved

With such a large area to cover, the team are very interested to hear from anyone who would like to volunteer with us.
In particular, we would be looking for people to:

  • Support our desk-based comparison of historical maps
  • Assist us in field work – especially if you know your historical woodland features, or Ancient Woodland Indicator species!

If you would like to get involved, please contact us at: