Ancient woodlands are areas that have been continuously wooded since at least 1600AD (1750 in Scotland). They are the primary woodlands with wildlife communities, structure and soils that have been modified the least. Ancient woodland contains a diverse number of species and is considered to be a historic part of our landscape which is irreplaceable.
There are two different types of ancient woodland:
- Ancient semi-natural woodland. This is woodland that has developed naturally.
- Plantations on ancient woodland. This is woodland planted on sites that previously contained ancient woodlands.
 Features and processes
Ancient woodland is typically composed of:
- Vegetation layers (canopy, understorey, field and ground).
- Irregular canopy structure.
- Veteran trees.
- Large amounts of dead wood (standing and fallen).
- Undisturbed soils.
- Sustained natural regeneration in gaps.
Ancient woodland and its associated soil have been shaped over centuries by the interaction of natural disturbance, local climatic conditions and soil conditions, solar radiation, temperature, atmospheric moisture and nutrient cycling.
Local planning authorities are advised to conserve and enhance biodiversity. In particular in relation to ancient woodlands, harm should be avoided wherever possible and the National Planning Policy Framework (nppf) states:
‘...planning permission should be refused for developments resulting in the loss or deterioration of irreplaceable habitats, including ancient woodland...unless the need for, and benefits of, the development in that location clearly outweigh the loss’.
Developments can affect ancient woodland directly through the loss of trees or damage to the root systems and soils, or through pollution incidents or changes to the woodland’s drainage or water table.
The locations of ancient woodland sites over two hectares have been mapped and are available online from the MAGIC website and Forestry Commission. The databases are not considered to be complete and therefore it may be necessary to commission an ecologist to undertake an ecological survey in order to identify any ancient woodlands within development sites or close to them, that may be unrecorded.
In January 2019, the Royal Town Planning Institute (RTPI) reported that just 2% of land in the UK is covered by ancient woodland and that they are threatened by the cumulative effects of inappropriate developments on their fringe as much as by permanent loss and damage.
Government guidance recommends that local authorities should refuse permission for developments that result in the loss of ancient woodland and ancient or veteran trees except in exceptional cases, but ancient woodland is not a formal statutory designation, and the evidence used to designate a site as ancient woodland could still be open to challenge by developers and other parties.
 Related articles on Designing Buildings Wiki.
- 11 things you didn't know about wood.
- Chain of custody.
- Definition of tree for planning purposes.
- Designated sites.
- Forest ownership.
- Forest Stewardship Council.
- National nature reserves.
- National parks.
- National Planning Policy Framework.
- Permission for felling or lopping a tree.
- Planning permission.
- Sustainably procuring tropical hardwood.
- Tree hazard survey.
- Tree preservation order.
- Trees in conservation areas.
- Types of land.
 External references
‘Structures and structural failure’ at IHBC’s Nottingham School, with Ed Morton (ex Canterbury, York and Westminster to St Paul’s) and John Ruddy.
Ageing gracefully - restorations which retain historical decay.