Native Woodland Survey of Scotland (NWSS)
The aim of the Native Woodland Survey of Scotland (NWSS) was to undertake a baseline survey of all native woodlands, nearly native woodlands and PAWS sites in Scotland in order to create a woodland map linked to a dataset showing type, extent and condition of those woods.
The objectives were to:
1. Identify the location, type, extent and condition of all native and nearly native woodlands and Plantations on Ancient Woodland Sites (PAWS - as identified from the Ancient Woodland Inventory) in Scotland.
2. Produce a baseline survey map of all native woodland, nearly native woodland and PAWS in Scotland.
3. Collect baseline information to enable future monitoring of the extent and condition of the total Scottish native woodland resource.
4. Provide information to support policy development and the delivery of social, environmental and development forestry.
The following datasets are available on the Scottish Forestry Open Data website:
- Native Woodland Survey of Scotland (base map and polygon level attributes)
- NWSS Canopy Structures
- NWSS Habitat Components
- NWSS Herbivore Impact
- NWSS Invasives
- NWSS Other Traits
- NWSS Species Structures
The following describes the layers available from Scottish Forestry and also gives an indication of the nature of the spatial data and the related component non-spatial data. (N.B. Every table contains a SCPTDATA_I field. This is a unique field which is used to link all other component tables). If you wish to carry out complex analysis, particularly involving elements of the components tables, e.g. species selection, you should do so using GIS software.
NWSS Map:
This is a straightforward view of the data which describes the type of NWSS polygon based on the following categories:
Native woodland: >50% native species in the canopy
Nearly-native woodland: >=40% and <=50% native species in the canopy
Open land habitat: <20% canopy cover, usually 100% surrounded by woodland and adjoining a native woodland
PAWS: A woodland area wholly or partially identified in the Ancient Semi-natural Woodland Inventory as ancient semi-natural but currently not semi-natural.
NWSS Nativeness:
Displays the percentage share of native species in the total canopy. This ranges from 0% to 100% in 5% classes.
NWSS Habitat:
This view of the data shows the priority woodland type and National Vegetation Classification (NVC) woodland community. Open land habitat is defined by UK Biodiversity Action Plan (BAP) type.
A dominant habitat is recorded for each polygon, however some polygons have habitats of equal dominance. In this case only one of the habitats is recorded in the top level spatial data. To identify all of the habitats in a particular polygon please refer to the FC_S_NWSS_HABITAT_COMPONENTS table or use the map browser identify tool on the NWSS Habitats layer.
Plantations on Ancient Woodland Sites (PAWS) may not display in the Habitat layer if a surveyor has not recorded a native priority habitat type for the site. This will happen when a site is non-native.
NWSS Canopy Cover:
Displays as a percentage, an assessment of the area covered by trees/shrubs. Values range from 0% to 100% in 10% classes. A minimum of 20% canopy cover is required to define woodland, so the 10% and 20% bands are skewed to allow for this.
NWSS Canopy Structures:
This displays the number of different structures recorded in a polygon (ranging from 0 to 6). The types of recorded structures are veteran, mature, pole immature, shrub, established regeneration or visible regeneration.
A dominant structure is recorded for each polygon, however some polygons have structures of equal dominance. In this case only one of the structures is recorded in the top level spatial data. To identify all of the structures in a particular polygon please refer to the FC_S_NWSS_CANOPY_STRUCTURES table or use the map browser identify tool on the NWSS Canopy Structures layer.
Information on the species identified in each polygon is also in the NWSS Canopy Structures layer and table.
* indicates a species which is classed as native for the purpose of the survey.
+ indicates a species is a shrub not a tree.
NWSS Semi-naturalness:
This view of the data shows the percentage of the polygon that is semi-natural. Values range from 0% to 100% in 10% bands.
NWSS Maturity:
This indicates the approximate stage of woodland development as either: mature, young, regenerating, mixed or shrub. The value is based on the dominance of the structures recorded; a mixed maturity means that none of the others values are dominant.
NWSS Other Traits:
This layer records whether or not there are any other attributes which have been recorded in the polygon. The details of any other traits that have been found can be accessed by viewing the related information attached to a polygon.
NWSS Herbivore Impact:
This view of the data shows the overall impact that herbivores have had on a polygon.
NWSS Invasives:
This is a separate spatial dataset on the Forestry Commission Spatial Data Repository. It contains a subset of the overall NWSS Map dataset which includes only those polygons were there is some presence of an invasive species. The layer is symbolised on the percentage of invasive species with the polygons, show in 25% bands. The data itself contains more detailed information which is broken down into 5% bands.
Summary of Attributes
SCPTDATA_I Polygon ID (Unique identifier)
PAWS_SURVY Surveyed as PAWS
TYPE Type
CANOPY_PCT Canopy cover percentage
NATIVE_PCT Native species percentage
DOM_HABITA Dominant habitat type
DOM_HB_PCT Dominant habitat type percentage
SEMINT_PCT Semi-natural percentage
STRUCT_NUM Number of structures
MATURITY Maturity
DOM_STRUCT Dominant structure
HERBIVORE Herbivore impact
ER_NAT_PCT Percentage of establish regeneration of native species
INVASV_PCT Invasive species percentage
INVASV_NUM Number of invasive species
OTHR_TRAIT Other traits recorded
HECTARES Area in hectares
Default
Identification info
- Alternative title
-
S_NWSS
- Metadata Language
- English
- Character set
- UTF8
- Dataset Reference Date (Creation)
- 2009-11-01
- Dataset Reference Date (Revision)
- 2014-02-03
- Identifier
- S_NWSS
- Presentation form
- Digital map
- Maintenance and update frequency
- Not planned
- Keywords
-
-
Forest Management
-
Grant Schemes
-
Planning
-
Environment
-
Felling
-
Landscape
-
Woodland
-
Licence
-
Ownership
-
Native
-
-
GEMET - INSPIRE themes, version 1.0
-
-
Habitats and biotopes
-
- Limitations on Public Access
- Other restrictions
- Other constraints
-
No limitations on public access
- Use constraints
- Other restrictions
- Other constraints
-
Please ensure that the following acknowledgement is displayed on any hard copy: Reproduced by Permission of Ordnance Survey on behalf of HMSO. © Crown copyright and database right [year]. Ordnance Survey Licence number 100043970.
- Other constraints
- Open Government Licence
- Spatial representation type
- Vector
- Denominator
- 10000
- Topic category
-
- Farming
- Biota
- Economy
- Environment
- Extent
-
GB-SCT
ISO3166-2 2007-12-13
))
Temporal reference
Temporal extent
Temporal extent
- Reference system identifier
- EPSG / OSGB 1936 / British National Grid (EPSG:27700) / 7.9
Distribution Information
Data format
- Data format
-
Name Version ESRI Shapefile
1.0
WMS
1.3.0
Transfer options
- Resource Locator
-
Protocol Resource Locator Name WWW:LINK-1.0-http--link
https://open-data-scottishforestry.hub.arcgis.com/ Scottish Forestry Open Data
WWW:LINK-1.0-http--link
https://forestry.gov.scot/forests-environment/biodiversity/native-woodlands/native-woodland-survey-of-scotland-nwss NWSS Guidance Document
OGC:WMS
https://ogc.nature.scot/geoserver/scottishforestry/ows?service=WMS&request=GetCapabilities Native_Woodland_Survey_of_Scotland
Data quality info
- Quality Scope
- Dataset
- Statement
-
A digital woodland map has been produced for the NWSS and the National Forest Inventory (NFI) using Ordnance Survey MasterMap® features and the most recent colour ortho-rectified aerial photography available at the time of mapping.
A suitable scale was used for the boundary interpretation and snapping, e.g. a scale of no less than 1:2500 is used to digitise 1:10000 data.
The woodland map shows the boundaries and locations of all woodlands in Scotland. The map is subdivided where visible differences in woodland occur, such as conifers, broadleaves and open spaces. These subdivisions are called Interpreted Forest Types (IFTs). Where a line is shown on MasterMap® to be within 10 m of the perceived woodland edge, IFT or Interpreted Open Area (IOA) boundary then that line was used as a polygon boundary. Where the boundary was different, it was captured by digitising along its edge. The map was supplemented by a spatial data layer identifying new native woodlands grant aided by Scottish Forestry (ex FCS). The IFT attributes are interpreted by the digitisers using the aerial photographs.
The IFTs are processed further to meet the requirements of the NWSS:
All polygons must be >0.5ha,
Conifer IFTs are removed if they are not in the Pine Zone or a PAWS.
Surveyors are given polygons from the database; they then modify and attribute these polygons according to the habitats they find in the field. Woodlands are fully surveyed if the have greater than 40% native species or they intersect a Plantation on Ancient Woodland (PAWS).
This database is then cleaned and analysed to produce the dataset that is stored on Geostore and published via the Scottish Forestry Map Browser.
The woodland map in Scotland was digitised using Ordnance Survey's Master Map (OSMM) topography layer dated between 2004 and 2007. OS aerial imagery dated 2006 - 2009 also formed the basis of the mapping exercise. Where OSMM features existed and were within 10m of the perceived woodland edge then OSMM was used as the basis of the woodland boundary, otherwise the woodland boundary was captured from the imagery.
Please Note: The Ordnance Survey's Positional Accuracy Improvement programme was completed in March 2006. PAI resulted in an improved and more consistent accuracy standard of 1:2500 mapping for rural areas. The PAI programme timeline overlapped with the digitising of the woodland map and this has resulted in an estimated 11% of the total area of the NWSS database being affected. As a result some features no longer align with the latest version of OSMM.
Metadata
- File identifier
- BB223316-8746-4338-9056-5D9A2F0D2824 XML
- Metadata Language
- English
- Character set
- UTF8
- Resource type
- Dataset
- Metadata Date
- 2023-06-22T10:47:49
- Metadata standard name
-
UK GEMINI
- Metadata standard version
-
2.3
Point of contact
- Individual name
-
GIS
- Organisation name
-
Scottish Forestry
- Position name
-
Head of Geo-Information Services
- Delivery point
-
Saughton House, Broomhouse Drive
- City
-
Edinburgh
- Administrative area
-
City of Edinburgh
- Postal code
-
EH11 3XD
- Country
-
United Kingdom
- Electronic mail address
-
geoinformationservices@forestry.gov geoinformationservices@forestry.gov.scot
- Role
- Point of contact