Protecting ancient woodland, ancient trees and veteran trees

Last updated: 2 July 2025

Ancient woodlands are defined as any area that has been wooded continuously since at least 1600 AD (or 1750 AD in Scotland).  According to the Woodland Trust, they comprise just 2.5% of the UK’s land area. As well as containing ancient and veteran native trees, these habitats also include specialist plant and fungal communities which have remained relatively undisturbed over long periods of time, in turn, they support important invertebrate, bird and mammal species.  

Because ancient woodland habitats, and individual ancient and veteran trees, have developed over such long periods of time (often many hundreds and sometimes more than a thousand years), these habitats and features are considered irreplaceable. 

Ancient trees are defined by their age. They have passed maturity and are incredibly old in comparison to other trees of the same species. As different trees age at different rates, there is no set age for a tree to be classed as ancient. Ancient trees can be identified by some common characteristics.  

A veteran tree is not as old as an ancient tree but has some similar features which will develop further over time. Veteran trees can be thought of as the ancient trees of the future. 

You can use the following inventories to identify ancient woodland, ancient trees and veteran trees. 
 

• The Woodland Trust’s Ancient Tree Inventory for Northern Ireland – ‘Back on the Map’ (click on ‘Tree search’ and enter a postcode/address) – only a small proportion of ancient or veteran trees are recorded on this inventory 

• The Woodland Trust’s Ancient Tree Inventory (UK wide) 
   

Ancient woodlands that are smaller than two hectares may not appear on these inventories. It’s therefore worth checking with your local records centre in case they hold data on smaller ancient woodlands.  

It’s important to note that not all ancient woodland will be recorded on these inventories, so if a site contains evidence of ancient woodland but it is not on the inventory you should contact the Woodland Trust in Northern Ireland.    

Development proposals can pose a serious threat to ancient woodland, ancient and veteran trees, and the wildlife that they support. Effects of development can be both direct (eg, damaging the whole tree, its roots or compacting soil) or indirect (eg, affecting protected species, such as bats or wood-decay insects).  

The Strategic Planning Policy Statement (paragraph 6.192) states that ‘Planning permission should only be granted for a development proposal which is not likely to result in the unacceptable adverse impact on, or damage to, known ancient and long-established woodland’. 

Local planning authorities (LPA) have a statutory duty under the Wildlife and Natural Environment Act (Northern Ireland) 2011 to conserve biodiversity as part of their functions. With regards to ancient trees and woodland, LPAs can carry out their biodiversity duty by safeguarding these habitats through their policy making and decision taking roles.  

The starting point for any development proposal should be to identify ways to avoid harmful impacts to ancient woodland or ancient and veteran trees, such as looking for alternative sites or redesigning the scheme. The next step is then mitigation of any impacts that can’t be avoided, and as a last resort compensation should be used to offset any unavoidable remaining impacts. 

This ‘avoid, mitigate, compensate’ approach is known as the mitigation hierarchy. 

Paragraph 6.193 of the Strategic Planning Policy Statement states that ‘A development proposal which is likely to result in an unacceptable adverse impact on, or damage to, habitats, species or features listed above may only be permitted where the benefits of the proposed development outweigh the value of the habitat, species or feature. In such cases, appropriate mitigation and/or  compensatory measures will be required.’ 

If an LPA decides to grant planning permission that results in unavoidable loss or deterioration of habitat (where exceptional reasons are demonstrated), they should apply the mitigation hierarchy to avoid significant harm to biodiversity.  

An example of exceptional reasons could be if the public benefit of an infrastructure project is considered to outweigh the loss or deterioration of habitat.   

Woodland Trust’s guidance on ancient woodland 

Woodland Trust’s guidance on ancient trees 

Biodiversity Duty - Guidelines for Public Bodies