Forests and woodlands | Scotland's soils

Topic sections

UK Forestry Standard
Collecting soil data
Soil data for the UK Forestry Standard
Soil data for woodland creation
Soil data for forests & climate change
Useful links

UK Forestry Standard

Healthy soils are the basis of a healthy forest. Understanding and protecting soils are crucial parts of sustainable forest management.

The UK Forestry Standard (UKFS) is the technical standard for sustainable forest management across the UK. It defines requirements and provides guidance on sustainable forest management. It is designed to be read in full for context. Chapter 8 outlines the requirements and guidelines for Forests and Soil. These aim to protect soils during activities such as cultivation, harvesting and drainage.

Scottish Government supports tree planting through the Forestry Grant Scheme, which Scottish Forestry administer. This support is only provided where UKFS requirements are met, and where there is confidence that the site is suitable for the trees being planted.

The UKFS is supported by other soils specific forestry guidance in Scotland:

Cultivation for upland productive woodland creation sites supports practitioners in making decisions about what cultivation techniques to use for upland productive woodland creation sites in Scotland. (includes a peat depth survey methodology)
Deciding future management options for afforested deep peatland explains the factors to consider when seeking felling approval from Scottish Forestry for forestry on peat soil.

Collecting soil data

Forest owners and managers need to gather soils data to comply with the UK Forestry Standard (UKFS). Data on soils are also needed to apply for Felling permission, for a forestry Environmental Impact Assessment (EIA) or the Forestry Grant Scheme.

For an initial assessment of the soil on a site, you can find useful background information from the maps available on this web site. The national maps are mostly at a scale of 1:250,000. This level of information could be useful for broad, pre-application discussions with a Conservancy and key stakeholders. However, forest planning and management decisions require more detailed information. Forest plans submitted to Scottish Forestry need to be mapped at a scale of 1:10,000. As publicly available soil maps are often not at this scale it is highly likely a site-based soil survey will be required, possibly supported by soil sampling and analysis, depending on circumstances and the availability of data. This will tell you how soils change across a site and inform planning and managements decisions.

Soil data and information required to comply with the UK Forestry Standard

The UKFS is clear about the importance of good soil management and how forestry soils should be managed to help achieve quality tree growth and sustainable forests. All forest and woodland managers must comply with the UKFS by addressing the key processes that damage forest soils: acidification, contamination, compaction, disturbance, erosion, fertility and organic matter.

The UKFS sets out a number of guidelines on how to comply with its requirements for soil. Table 1 provides links to soil data and information that can help implement these requirements at different stages of the forest management cycle. In many cases, field-level assessment will also be required. Table 1 only includes UKFS Soil requirements and guidelines that can be informed by existing maps and their associated data.

Table 1: Where to find soils data and information to help implement the UKFS at key stages of the forest management cycle.

Woodland creation due diligence and forest plan scoping stage

UKFS requirements & guidelines for soils at each forest management stage		Existing data which can help provide background information	How to obtain further detail required
Peat depth	Good Forestry Practice Requirement 4: New forests should not be established on soils with peat exceeding 50 cm in depth – or a depth specified in country guidance – or on sites that would compromise the hydrology of adjacent bog or wetland habitats.	Carbon and peatland 2016 map can be used to identify areas where peat is likely to be found (but not its depth)	Peat survey
Peat depth	Soil Guideline 20: Consider, informed through tools such as a peat assessment, the balance of benefits for carbon and other ecosystem services before making the decision to restock (or regenerate) on soils with deep peat, ensuring the decision complies with relevant country practices.	No suitable map available	Peat survey
Vulnerability to erosion	Soil Guideline 13: Consider woodland creation to protect erosion-prone soils, stabilise slopes and intercept sediment-laden run-off from upslope.	OS mapping layer (scale 1:10,000) available on most digital maps, to identify gradient Soil erosion and runoff risk maps (cover agricultural areas and adjacent uplands at a scale of 1:25,000)	Soil survey alongside aerial photography, topography and vegetation
Risk of slope failure	Soil Guideline 15: On steep slopes where there is a risk of slope failure or serious erosion, use native species and low impact silvicultural systems including continuous cover forestry where possible.	OS mapping layer (scale 1:10,000) available on most digital maps, to identify gradient	Interpretation using soil type alongside aerial photography, topography and vegetation

Work plan stage

UKFS requirements & guidelines for soils at each forest management stage		Existing data which can help provide background information	How to obtain further detail required
Soil type and suitability	Good Forestry Practice Requirement 1: At planning and operational stages, the quality of forest soil in terms of its physical, chemical and biological properties should be protected so that it is maintained, and where appropriate, enhanced.	National soil map of Scotland (covers the whole of Scotland at a scale of 1:250,000) Soil map of Scotland (partial cover) (covers agricultural areas and adjacent uplands at a scale of 1:25,000) The soil types in parts of the National Forest Estate can be found on the UK Soil Observatory	Use field evidence (e.g. from soil pits) and interpretation (e.g. from topography, vegetation and current land use)
Vulnerability to erosion	Good Forestry Practice Requirement 2: Forest operations should be planned and managed to minimise compaction and damage to soil structure and function by using appropriate measures. Should damage occur, reinstatement should be undertaken and adverse effects mitigated.	OS mapping layer (scale 1:10,000) available on most digital maps, to identify gradient Risk maps show areas of soil at risk of erosion, runoff, leaching and both topsoil and subsoil compaction (cover agricultural areas and adjacent uplands at a scale of 1:25,000)	Interpretation using soil type alongside aerial photography, topography and vegetation
	Good Forestry Practice Requirement 3: The environment adjacent to forests should not be subject to adverse effects due to soil disturbance associated with woodland creation or forest management practices.
	Good Forestry Practice Requirement 4: New forests should not be established on soils with peat exceeding 50 cm in depth – or a depth specified in country guidance – or on sites that would compromise the hydrology of adjacent bog or wetland habitats.
	Soil Guideline 11: Consider the potential impacts of soil disturbance when planning operations involving cultivation, harvesting, drainage and road construction; minimise the soil disturbance necessary to secure management objectives, and amend practices to manage the risks posed.
	Soil Guideline 14: Address the risks of soil erosion as part of the forest and operational planning processes, ensuring mitigation measures are implemented when the soil will be exposed.
Soil fertility	Soil Guideline 17: Choose tree species and silvicultural systems that are well suited to the site and, with the exception of short rotation forestry or short rotation coppice, do not require continuing inputs of fertilisers.	Ecological Site Classification Decision Support System (ESC-DSS)	For ESC, use evidence collected from field surveys rather than default values
Risk of increased acidification	Soil Guideline 1: On soils classified as at high risk of increased soil and water acidification, avoid short rotation forestry or short rotation coppice, and the harvesting of whole trees, forest residues and tree stumps.	Catchments vulnerable to acidification	Not needed

Forest operations

UKFS requirements & guidelines for soils at each forest management stage		Existing data which can help provide background information	How to obtain further detail required
Soil fertility	Soil Guideline 16: Unless the site is part of an approved peatland restoration project, ensure the removal of forest products from the site, including non-timber products, does not deplete site fertility or soil carbon over the long term and maintains the site potential.	No maps suitable for forestry are available	Soil survey
	Soil Guideline 18: Minimise the use of fertilisers and confine these to areas where analysis clearly shows management benefits; if they will be used, plan applications to minimise the risk of nutrient loss.
	Soil Guideline 19: To minimise soil carbon loss, employ techniques for ground preparation that create the minimum amount of soil disturbance but are still adequate to ensure successful establishment.
	Soil Guideline 20: Consider, informed through tools such as a peat assessment, the balance of benefits for carbon and other ecosystem services before making the decision to restock (or regenerate) on soils with deep peat, ensuring the decision complies with relevant country policies.
Vulnerability to compaction or erosion	Soil Guideline 6: Minimise compaction, rutting and erosion during forest operations by selecting the most appropriate working method for site conditions; monitor operations and modify, postpone or stop procedures if soil damage starts to occur.	OS mapping layer (scale 1:10,000) available on most digital maps Risk maps show areas of soil at risk of erosion, runoff, and both topsoil and subsoil compaction (cover agricultural areas and adjacent uplands at a scale of 1:25,000)	Interpretation using soil type alongside aerial photography, topography and vegetation
	Soil Guideline 7: On sites vulnerable to compaction and erosion, consider the weather and avoid working during periods of heavy or exceptional rainfall; plan for changes in the weather that could affect site conditions, and suspend operations if necessary.
	Soil Guideline 8: Maintain adequate brash mats throughout extraction where operations provide this material. If brash is not available, use other techniques to protect the soil.
	Soil Guideline 9: Where compaction has occurred and will affect tree growth or lead to other detrimental effects, apply remedial treatment, but minimise the soil disturbance involved.
Soil acidity	Soil Guideline 5: When restoring brownfield sites, seek specialist advice, especially if measures are needed to ameliorate excess soil acidity.	No maps available	Soil analysis of selected samples
Risk of increased acidification	Water Guideline 15: When planning and cultivating restocking sites, seek to minimise the amount of brash placed into mounding spoil trenches.	Catchments vulnerable to acidification Water classification hub - catchments identified as failing / at risk of failing good status due to acidification	Not needed

Soil data and information to assess a site for woodland creation

Table 2 provides links to soil related maps that can provide information when assessing a site for a woodland creation proposal. It also highlights where field-level assessment is more appropriate. Table 2 only includes the information that can be gained from publicly available maps and data.

Woodland creation applications submitted to Scottish Forestry should refer to the FC soil classification system. This system is used widely in forest soil survey work and is explained in the FC Field Guide: The identification of soils for forest management. A table to help you translate data from the Soil Survey of Scotland classification into the FC classification system is given in FC soil codes translation table.

You can find guidance on Protecting and managing soil in forests on the Scottish Forestry website.

Table 2: Where to find soils data and information to help support a woodland creation proposal

Soil data and information to consider in a woodland creation proposal	Existing data which can help provide background information	How to obtain further detail required
Soil type	National soil map of Scotland (covers the whole of Scotland at a scale of 1:250,000) Soil map of Scotland (partial cover) (covers agricultural areas and adjacent uplands at a scale of 1:25,000)	Soil survey and interpretation
Land suitability for woodland creation	National scale Land Capability for Forestry (covers the whole of Scotland at a scale of 1:250,000)	Soil survey and interpretation
Land capability for agriculture	National scale Land Capability for Agriculture (covers the whole of Scotland at a scale of 1:250,000) Land capability for agriculture (partial cover) (covers agricultural areas and adjacent uplands at a scale of 1:50,000)	Not needed
Presence of deep peat (peat layer greater than 50 cm)	Carbon and peatland 2016 map - areas where peat is likely to be found (but not its depth)	Peat survey
Digital terrain	OS mapping layer (1:10,000) available on most digital maps	Not needed
Vulnerability of soils to erosion, compaction and runoff	Risk maps show areas of soil at risk of erosion, runoff, leaching and both topsoil and subsoil compaction (cover agricultural areas and adjacent uplands at a scale of 1:25,000)	Interpretation using soil type alongside aerial photography, topography and vegetation

Using soils data to inform the response of a forest to climate change

In order to comply with the UKFS Requirements for forests and climate change, forest managers should:

consider how forests contribute to mitigating climate change by capturing and storing carbon;
plan and manage forests to enhance their resilience and mitigate the risks posed from climate change.

Managing the carbon in forest soil is important as there may be more carbon stored in the soil than in the tree biomass, especially in peat. Data on where peat lies, and at what depth, will help determine if woodland creation or restocking is appropriate, and help identify where action should be taken to maintain soil fertility and soil carbon.

Accurate soils data will help plan and manage a forest to increase its resilience to the risks posed by climate change. Climate change projections suggest that, on some sites and for some species, growing conditions will become more challenging, especially where summer drought coincides with free-draining soils. The Ecological Site Classification Tool (ESC4) takes into account climate change projections for 2050 and 2080, for which it is important that accurate soils data is used.

Find out more about forests and climate change on the Scottish Forestry website.