Native, semi-natural broadleaved woodland that occurs on acid or base-poor soils that may be either dry or humid, but not waterlogged. Woodland on humus deposits are included, but not peats.
Stands are usually dominated by Sessile Oak (Quercus petraea), or mixed stands of Sessile and Pedunculate Oak (Q. petraea and Q. robur) or their hybrids. Other common trees include Downy Birch (Betula pubescens), Holly (Ilex aquifolium) and Rowan (Sorbus aucuparia). Downy Birch (Betula pubescens) can be the dominant tree in some situations.
In places where the soils are less acid, Ash (Fraxinus excelsior) and Hazel (Corylus avellana) may also be present in small numbers. If either of these tree species is abundant, consider the following category, oak-ash-hazel woodland - WN2. The ground flora typically comprises Ling (Calluna vulgaris), Bilberry (Vaccinium myrtillus), Bracken (Pteridium aquilinum), Hard Fern (Blechnum spicant), Great Wood-rush (Luzula sylvatica), Velvet Bent (Agrostis canina), Common Cow-wheat (Melampyrum pratense) and Wood Sage (Teucrium scorodonia). The climber, Honeysuckle (Lonicera periclymenum), is also common. The cover of mosses and lichens in the ground flora and on trees is often very high.
Links with Annex I: Corresponds to the annexed habitat, ‘old sessile oak woods with Ilex and Blechnum in the British Isles (91A0)’.