Native broadleaf woodland
What is it?
The following categories of woodland are all considered to be broadleaved woodland (as defined by the current UK Biodiversity Action Plan).
Ancient semi-natural woods (semi-natural stands on ancient sites)
Other semi-natural woods (semi-natural stands on more recent woodland sites)
Planted woods on ancient woodland sites where the composition is mainly site native species (over 50% of the canopy)
Other planted woods of mainly native species (over 50% of the canopy is site-native species), where the agreed aim is to manage towards a more semi-natural structure and composition
New native woodlands created to mimic the natural composition of the woodlands on the site
To qualify as a Habitat Action Plan (HAP) woodland, a site must have:
20% or more canopy cover, or the potential to achieve this in the case of newly planted stands.
A canopy composed of 50% or more site-native species of trees or shrubs (or will be at canopy closure in the case of younger stands). Site native trees are those which are native to the locality and capable of growing naturally on the site, ie. they can successfully colonise and complete their life cycle.
There are several categories of native broadleaf woodland:
Lowland mixed deciduous woodland
This is a large category that incorporates most of the semi-natural woodland in southern and eastern England, and in parts of lowland Wales and Scotland (as well as relevant planted native broadleaved woods). Despite great variety in the species composition of the canopy layer and the ground flora, some features are common to many stands:
Occurs largely within enclosed landscapes, usually on sites with well-defined boundaries
Many are ancient woods.
Most sites are relatively small, less than 20 ha.
Most were traditionally coppiced, particularly those on moderately acid to base-rich soils; on very acid sands the type may be represented by former wood-pastures of oak and birch.
Pedunculate oak (Quercus robur) is generally the commoner oak (although Sessile oak (Quercus petraea) may be abundant locally) and may occur with virtually all combinations of other locally native tree species.
Lowland beech and yew woodland
Lowland beech and yew woodland spans a variety of distinctive vegetation types reflecting differences in soil and topographical conditions. Calcareous beech and yew forms perhaps 40% of the total amount of this priority habitat, beech woodland on neutral-slightly acidic soils comprised about 45%, and acidic beech the remaining 15%.
For Calcareous beech and yew woodland, Beech woodland on neutral-slightly acidic soils and Acidic beech woodland see the UK Biodiversity Action Plan.
Alder, birch and willows are usually the predominant tree species, but sometimes ash, oak, pine and beech occur on the drier riparian areas [do we need to explain ‘riparian’?]. Succession from open herbaceous wetlands results in a wide range of structures and compositions, determined by the composition of the original vegetation, the climate and the nutrient status. There is frequently a mixture of ‘dry-land’ species, for example around the base of large alders or willow.
The situation in the South East
The following data concerns broadleaf native woodland and consists the combination of the above woodland types.
|Extent in England||251,000 ha
|Extent in the SE region||153,680 ha
|Percentage UK resource in the SE||61%|
|Extent covered by SSSI designation||data to be added
Rate of Change
|County||1998 extent (ha)||2008 extent (ha)|
|Isle of Wight||unknown||3,848|
The main threats to the woodland in the region are as follows:
- Replanting with conifers and clearance for agriculture leading to loss of habitat or changes in the composition and structure of the woodland.
- Grey squirrels (and in the Chilterns, edible dormouse Glis glis) strip the bark from beech trees (between 10 and 40 years old) which can result in tree death, disruption of normal age structure and shifts in species composition; rabbits can also cause damage (bark stripping and eating regeneration) in some beech and yew areas.
- Deer browsing on seedlings and saplings, is a widespread problem, which limits capacity for regeneration.
- Introduced species, that replace native beech and yew woodland species. Some woods were planted with conifers in the past; locally, invasive species may include sycamore, rhododendron, Turkey oak Quercus cerris and cherry laurel Prunus laurocerasus
- The predominance of the older age classes (older trees) has increased the susceptibility of the trees to damage from droughts and storms.
- Lack of management, or unsympathetic management, due to lack of interest, expertise and incentives amongst owners.
- Air pollution may increasing tree susceptibility to disease and damage epiphyte populations
- Fragmentation of the habitat as a result of development.
- Climate change, potentially resulting in changes in the vegetation communities.
- Wet woodland has been affected by the lowering of water-tables through drainage or water abstraction, flood prevention measures, river control and canalisation resulting in change to drier woodland types.
- Wet woodland has also been affected by poor water quality arising from eutrophication, industrial effluents or rubbish dumping leading to changes in the composition of the ground flora and invertebrate communities.
Vision for native broadleaf woodland
The South East Biodiversity Forum’s vision for this habitat is that there should be:
- No further loss of existing habitat
- Good management, including where appropriate pest (eg. deer) control, visitor management.
- No damage to site integrity from activities arising outside the sites, eg. inadequately managed public access
- Re-creation of lowland woodland on appropriate sites to restore some past losses, including the linking up of fragmented sites
- Greater public appreciation of woodlands and their specialist wildlife, including greater awareness of the impacts of human pressures, such as dog-walking, mountain-biking, and dumping of waste
- Creation of alternative green space around important woodland areas under pressure for increasing new housing, such as the New Forest
How can we deliver this vision?
- Forestry Commission Forest Design Plans (http://www.forestry.gov.uk/forestry/infd-7bbkt4)
- Provision of land management advice by statutory (Natural England) and non-statutory agencies (NGOs)
- Agreements under Higher Level Stewardship
- Project funding (SITA Trust, WREN etc)
- Site management plans
- Land purchase/management agreements by NGOs
- River restoration linked to Water Framework Directive Programme of measures (wet woodland)