The National Forest Inventory (NFI) is the most recent programme of Forest Research to survey British trees and woodland. It does this through a combination of remote sensing and field visits to 15,000 one-hectare sample plots across Britain. This year, the satellites and their earthly plotters completed the second in a series of 5-year cycles mapping every woodland in Great Britain. Forest Research are currently running a review of this service. In investigating how we might respond, it has become clear that there is a treasury of mapped coppice here and more for us to contribute ahead.
Since 1924 the Forestry Commission’s inventory work has periodically recorded the size, distribution, composition, and condition of British woodlands and so too the changes taking place in those woodlands over time. The timeline below shows its various incarnations over the past century and the published milestones of this work.
Table 1: Development of Forest Research mapping since 1924
The results of the survey conducted between 1995 and 1999 were subsequently published in 2003 as the National Inventory of Woodland and Trees (NIWT). This was the last full description of the character of British woodlands produced by Forest Research in a report format. NIWT also provided detailed analysis of each of the 3 countries, which was further broken down into separate reports for 9 regions and 46 counties in England, 6 historic counties of Wales and 10 in Scotland. At this time coppice represented 0.9% of British woodland cover. The source of the sample table below leads to similar tables for Kent, Dorset, Hampshire, Lincolnshire, Lothian, and Gwent.
Table 2: 3 Woodlands of Britain by Country and Forest Type
Since 2009 FR’s survey work has been conducted under the banner of the National Forest Inventory. This work is continuous and currently produces annual outputs, available on the Forestry Commission’s ‘Open Data’ website for public use in digital mapping.
What counts as woodland?
The NFI, which started in 2009, covers any forest or woodland of at least 0.5 hectares in area; with a minimum width of 20 m; and that has at least 20% tree canopy cover (or the potential to achieve this). These criteria conform to European forest inventories so that data can be reported and shared internationally. NFI also uses its sample field surveys to maintain monitoring of smaller areas of woodland: of 0.1 to 0.5 hectares; trees in linear features (hedges); trees in groups and single trees.
How is the NFI used?
NFI data and reports are used by many people and organisations involved in forestry and land management, and in the wider world of planning, policy development and business.
The NFI programme works closely with the FC’s plant health teams and with other colleagues to provide information to help estimate impact and to formulate policy in response to disease outbreaks and natural events such as storms.
Coppice in the National Forest Inventory
The National Forest Inventory makes specific reference to coppice, identifying coppice and coppice with standards as distinct forest types. While it might seem that coppice has not recently featured strongly in portraits of UK industry or forest planning at a national level, the National Forest Inventory still has a whole chapter of its current guidance on field sampling devoted to coppice. This is well worth a read to see how scientific surveying manages the complexities of mapping multi-stemmed trees, regularly cut to the ground and re-growing, and recently tending towards being over-stood. While not part of the current consultation, it might also benefit from a review by NCFed members, as users of coppice woodland. Chapter 17 of the Survey Manual, devoted to coppice can be downloaded here – https://www.forestresearch.gov.uk/documents/3159/17-Coppice-V3.pdf
Figure 1: Sample Map showing coppice from National Forest Inventory GB 2018
How to Use the National Forest Inventory maps
Here are some basic instructions for viewing NFI maps:
Find a dataset (this is a collection of digital mapping files that represent the land we stand on, coloured with trees!)
- Go here – http://data-forestry.opendata.arcgis.com 
- Use the search bar (just below where it says, ‘Find Data’) and type in ‘National Forest Inventory’. Hit ‘Enter’ to get the results.
- At the top-right of the resulting page, you can sort the resulting datasets. If you select ‘Date created’ as the sort criteria, it will put the most recent (currently the 2018 surveys, published at the end of 2019) to the top.
- Click on the title of the dataset you want to view e.g. National Forest Inventory Woodland GB 2018.
- This takes you to another page for the most recent datasets… or
- … invites you to download a zip file for anything dated 2016 and earlier.
View your data as a map (… for more recent data)
- Click ‘Create Webmap’ from the list on the right, below the word ‘About’, and it opens an ArcGIS webpage, under licence to Forest Research
- The ArcGIS website briefly flashes up an invitation to ‘Sign In’ while it recognises the FC licence. Wait until …
- The webpage loads showing a map and a key, featuring ‘Coppice’ as the brightest green
- It speeds up the process of drawing all the elements of the map in any location if you zoom in a bit before it starts showing woods. Use the + or – buttons to zoom in or out.
- To move the map around, right-click and hold
- Once you can see a woodland, click on it to reveal the area and its classification as a forest type.
- There’s a ‘Description of attributes’ document which includes clues about how coppice is located from aerial photography here, https://www.forestresearch.gov.uk/documents/2773/NFI-Description-of-attributes.pdf
Finding your Coppice
Perhaps you can use National Forest Inventory to find the coppice that you work, manage, visit, or own, by way of the records above. Be aware that the practicalities of building these maps means that sometimes the character of the wider woodland governs its forest type and coppice is not drawn in a place, even when it is known to be there.
Keep in touch if you find any anomalies between maps and land and we can see if there is a way to set the records straighter. Email firstname.lastname@example.org to let us know about coppice missing from the map or offer feedback about the NFI and its services.
 This is the collaborative research hub for national forestry bodies of England, Wales, and Scotland
 National Inventory of Woodland and Trees, NFI (2003) – https://www.forestresearch.gov.uk/tools-and-resources/national-forest-inventory/national-inventory-of-woodland-and-trees/ , accessed 15.7.20
 “Contains Forestry Commission information licensed under the Open Government License v3.0.”