Scottish Forestry - Woodland Carbon Code information: EIR release

Information requested

1). The Woodland Carbon Code (WCC) version 3.0 (January 2026) provides links to a document titled ‘Soil Carbon and the Woodland Carbon Code’ (Vicky West, 14 July 2011, 10 pages). This document claims on page 5 that:

Research recognises that there can be initial losses to soil carbon on organomineral soils, but that depending on the intensity of the ground preparation and ongoing management, there can be subsequent gains to soil carbon as woodlands grow and mature.

In respect of the above paragraph, it appears that the ‘initial losses’ are supposedly determined through a percentage loss of carbon from the soil due to disturbance resulting from forestry techniques such as hand turfing, mounding, ploughing and scarifying (as referred on pages 5-6).

However, the same sentence says (for organo-mineral soils) ‘there can be subsequent gains to soil carbon as woodlands grow and mature’. Please could you provide and/or identify the specific research source(s) that reaches this conclusion.
Although the document has eight references (page 9), it is unclear if any of these items of research contains the assertion (and if this is substantiated) that ‘there can be subsequent gains to soil carbon as woodlands grow and mature’.

2). Page 5 of this same (14 July 2011) document states:

Further research in the next 2-3 years will allow us to develop more reliable figures for rates of soil carbon accumulation. Results of this research will be used in the next Woodland Carbon Code update on soil carbon. Projects will be able to update their soil carbon estimates at the first verification, based this research and update.

In respect of the ‘further research in the next 2-3 years’ being used to ‘develop more reliable figures for rates of soil carbon accumulation’, please could you provide the research paper title(s) and author(s) of all research relating to potential post-planting soil carbon changes, not just for the 2-3 years after July 2011, but up to the present day. The above sentence seems to make the presumption that soil carbon accumulates post-planting (presumably after allowing for carbon losses from initial disturbance). As this research may instead show soil carbon is lost post-planting (long after initial disturbances to soil through establishment preparation and planting), it appears Scottish Forestry/WCC might also hold research and/or information from July 2011 to the present day demonstrating that soil carbon is lost over the longer term, not just from initial disturbances to soil through preparation and planting. Please ensure these research paper titles and authors are also provided.

Note: when I refer to soil carbon losses over the longer term, I mean soil carbon losses that are not due to disturbance to the soil through establishment preparation and planting (such as hinge mounding or scarifying), but due to physical, biological and other changes occurring due to the introduction of trees to the soil, and the subsequent growth of these trees over the long term (years and decades).

3). Page 5 of the 14 July 2011 document states ‘Results of this research will be used in the next WCC update on soil carbon’. If this research exists (and has been requested above in point 2), was this research actually published, and where? Was this research used to update any future WCC(s), and if so, which updates did they feature in?

4). If there was research suggesting soil carbon increases over time and this was used to update the WCC, have projects subsequently been able to ‘update their soil carbon estimates at the first verification’?

5). Given the 14 July 2011 document suggests ‘there can be subsequent gains to soil carbon as woodlands grow and mature’ it is unclear as to what the previous or current assumptions of the WCC are in relation to changes in soil carbon after the initial establishment phase. Is it the case that the WCC version 3 and all previous versions assume (or assumed) that there is no change in soil carbon for the duration of the project after the initial loss of soil carbon due to the initial establishment phase?

6). Research has shown that carbon continues to be lost from the soil for many years after planting for some sites, thus contradicting (a) the suggestion in the 14 July 2011 document that organo-mineral soils gain carbon over time after planting, and (b) any assumptions (potentially held by the WCC and others) that soil carbon in organo-mineral soils remain constant over time after planting.

For example, a paper by Friggens et al. (2020) ‘Tree planting in organic soils does not result in net carbon sequestration on decadal timescales’, appears to demonstrate that soil carbon decreased significantly for some sites. Another paper, by Joly et al. (2025) ‘Temperate grassland conversion to conifer forest destabilises mineral soil carbon stocks’, appears to suggest that the WCC does ‘not yet include an assessment of possible changes of soil C stocks following afforestation’.

Given that (according to the 14 July 2011 document) there was an apparent willingness to update the WCC in line with any research showing increases in soil carbon stock following planting (and apply this change at the first verification), are the WCC planning to update the WCC to account for long-term declines in soil carbon stocks post-planting, as several research papers demonstrate?

7). If the WCC is revised to account for long-term soil carbon losses post-planting, will this be applied to any existing projects? If so, which ones? If applied would this change occur to those projects awaiting all subsequent verifications over

8). Please can the WCC provide all information relating to discussions or correspondence relating to possible revisions to the WCC to account for long-term soil carbon changes post-planting for both mineral soils and organo-mineral soils This would be all correspondence with third parties and all internal correspondence with the WCC and Scottish Forestry.

9. Please can you provide the names and/or job titles of the staff with the WCC and Scottish Forestry who are responsible for proposing changes or revisions to the WCC, along with the names and job titles of staff with the WCC, Scottish Forestry and anyone else in the Scottish Government who are responsible for implementing or rejecting proposed changes or revisions to the WCC.

Response

As the information you have requested is ‘environmental information’ for the purposes of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are required to deal with your request under those Regulations. We are applying the exemption at section 39(2) of the Freedom of Information (Scotland) Act 2002 (FOISA), so that we do not also have to deal with your request under FOISA.

This exemption is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exemption. We have found that, on balance, the public interest lies in favour of upholding the exemption, because there is no public interest in dealing with the same request under two different regimes. This is essentially a technical point and has no material effect on the outcome of your request.

Response to your questions 2 and 8:

While our aim is to provide information whenever possible, after conducting a thorough search across the organisation, I can confirm that we were unable to provide any information regarding parts 2 and 8 of your request, as Scottish Forestry does not hold any information within this scope. This is a formal notice under section 10(4)(a) of the Environmental Information (Scotland) Regulations 2004 (the EIRs), informing you that Scottish Forestry does not hold the information you requested.

We acknowledge the distinction between compile and create under Regulation 9 of the Environmental Information (Scotland) Regulations 2004 (the EIRs) (Advice and assist). However, in this particular case, the requested information cannot be compiled, as no Scottish Forestry information in recorded form exists that would fall within the scope of this request.

Under Regulation 10 (4) (a) of the Environmental Information (Scotland) Regulations 2004 (the EIRs), we are required to provide only information held at the time of the request.

Under Regulation 9 (Advice and Assist) of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are not required to create new information to provide a response. Accordingly, the information you have requested in parts 2 and 8 of your request is not held by Scottish Forestry.

Please refer to Annex A below for a more detailed explanation of the exception applied.

Response to your questions 1, 3, 4, 5, 6, 7, and 9:

The answers to your questions are provided below:

Question 1: The Woodland Carbon Code (WCC) version 3.0 (January 2026) provides links to a document titled ‘Soil Carbon and the Woodland Carbon Code’ (Vicky West, 14 July 2011, 10 pages). This document claims on page 5 that:

Research recognises that there can be initial losses to soil carbon on organo-mineral soils, but that depending on the intensity of the ground preparation and ongoing management, there can be subsequent gains to soil carbon as woodlands grow and mature.

In respect of the above paragraph, it appears that the ‘initial losses’ are supposedly determined through a percentage loss of carbon from the soil due to disturbance resulting from forestry techniques such as hand turfing, mounding, ploughing and scarifying (as referred on pages 5-6).

However, the same sentence says (for organo-mineral soils) ‘there can be subsequent gains to soil carbon as woodlands grow and mature’. Please could you provide and/or identify the specific research source(s) that reaches this conclusion. Although the document has eight references (page 9), it is unclear if any of these items of research contains the assertion (and if this is substantiated) that ‘there can be subsequent gains to soil carbon as woodlands grow and mature’.

Response to your question 1:

Relevant research is presented in these two papers:

• Morrison et al (2012) Understanding the Carbon and GHG balance of UK Forests, Forest Research
• Read DJ, Freer-Smith PH, Morison JL, Hanley N, West CC, Snowdon P (eds) (2009) Combating climate change – a role for UK forests. An assessment of the potential of the UK’s trees and woodlands to mitigate and adapt to climate change. The Stationery Office, 

While our aim is to provide information whenever possible, in this instance we are unable to provide some of the information you have requested because an exception under Regulation10(5)(c) of the Environmental Information (Scotland) Regulations 2004 (the EIRs) applies to the above-mentioned publications. These were found and located by the relevant Scottish Forestry division and used when writing and compiling the answers to your review request.

Please refer to Annex A below for a more detailed explanation of the exception applied in this response.

Question 3: Page 5 of the 14 July 2011 document states ‘Results of this research will be used in the next WCC update on soil carbon’. If this research exists (and has been requested above in point 2), was this research actually published, and where? Was this research used to update any future WCC(s), and if so, which updates did they feature in?

Response to your question 3:

There is ongoing work to collect further data on soils to inform the WCC models in future. Through Forest Research, the WCC team has organised the collection of soil carbon data at over 140 WCC sites as part of this work. Forest Research is analysing these data and once this is complete, we hope to provide a more detailed soil carbon calculator. Information is provided on this page of the WCC website alongside other developmental work that we are taking forward – see Soil Carbon

Updates to the carbon calculator for the Woodland Carbon Code since Version 1.0 can be found here on the “Version control” tab. It should be noted that ongoing research by Forest Research and others informs the development of the Forest Research forest carbon models. As such, the Woodland Carbon calculator, including handling of soils, is based on the current state of the science rather than a specific piece of research necessarily.

Where information is already publicly available, links to the relevant webpages are provided. Under Regulation 6(1)(b) of the EIRs, we are not required to provide you with information that is readily available online.

Please refer to the attached documents (Annex B to this response) for further information on this matter.

An exception under Regulation 11 (2) of the EIRs (personal information) applies to some of the requested information because it constitutes third-party personal data. You will be able to identify where names have been redacted in the released document.

Question 4: If there was research suggesting soil carbon increases over time and this was used to update the WCC, have projects subsequently been able to ‘update their soil carbon estimates at the first verification’?

Response to your question 4: Research evidence indicates that soil carbon can accumulate over time under woodlands. Woodland Carbon Code guidance states on p. 5:

"Under certain conditions, with minimal ground disturbance, soil carbon can accumulate as a woodland grows. Currently it is only possible to claim for this accumulation for a woodland managed as minimum intervention (without thinning or clear felling), which is on mineral soil and was previously in arable use."

The Woodland Carbon Code calculator indicates on the “Version control” tab that a soil carbon accumulation column was added to the calculator in 2018.

Where information is already publicly available, links to the relevant webpages have been provided. Under Regulation 6 (1) (b) of the EIRs, we are not required to provide you with information that is readily available online.

Please refer to the attached documents (Annex B to this response) for further information on this matter.

An exception under Regulation 11 (2) of the EIRs (personal information) applies to some of the requested information because it constitutes third-party personal data. You will be able to identify where names have been redacted in the released document.

Question 5: Given the 14 July 2011 document suggests ‘there can be subsequent gains to soil carbon as woodlands grow and mature’ it is unclear as to what the previous or current assumptions of the WCC are in relation to changes in soil carbon after the initial establishment phase. Is it the case that the WCC version 3 and all previous versions assume (or assumed) that there is no change in soil carbon for the duration of the project after the initial loss of soil carbon due to the initial establishment phase?

Response to your question 5: As noted above under Q4, carbon accumulation can only be claimed under the Woodland Carbon Code on mineral soils in a woodland with minimum intervention where the previous land-use is arable.

Where information is already publicly available, links to the relevant webpages have been provided. Under Regulation 6 (1) (b) of the EIRs, we are not required to provide you with information that is readily available online.

Question 6: Research has shown that carbon continues to be lost from the soil for many years after planting for some sites, thus contradicting (a) the suggestion in the 14 July 2011 document that organo-mineral soils gain carbon over time after planting, and (b) any assumptions (potentially held by the WCC and others) that soil carbon in organo-mineral soils remain constant over time after planting.

For example, a paper by Friggens et al. (2020) ‘Tree planting in organic soils does not result in net carbon sequestration on decadal timescales’, appears to demonstrate that soil carbon decreased significantly for some sites. Another paper, by Joly et al. (2025) ‘Temperate grassland conversion to conifer forest destabilises mineral soil carbon stocks’, appears to suggest that the WCC does ‘not yet include an assessment of possible changes of soil C stocks following afforestation’.

Given that (according to the 14 July 2011 document) there was an apparent willingness to update the WCC in line with any research showing increases in soil carbon stock following planting (and apply this change at the first verification), are the WCC planning to update the WCC to account for long-term declines in soil carbon stocks post-planting, as several research papers demonstrate?

Response to your question 6: The Woodland Carbon Code calculator already accounts for soil carbon emissions after planting. It assumes that all these emissions happen immediately rather than being spread over a number of years.If an assumption is applied in the calculator that the intervention technique for planting involves high disturbance, and the soil is organomineral, the calculator will typically show that the woodland does not achieve a positive carbon balance for 10 or 20 years or more and that no carbon credits are issued until after this period. We believe that that the transparent nature of the calculator, incorporating these more prolonged carbon emissions, acts as a deterrent to management practices that involve higher levels of soil carbon emissions.

Where information is already publicly available, links to the relevant webpages have been provided. Under Regulation 6 (1) (b) of the EIRs, we are not required to provide you with information that is readily available online.

Please refer to the attached documents (Annex B to this response) for further information on this matter.

An exception under Regulation 11 (2) of the EIRs (personal information) applies to some of the requested information because it constitutes third-party personal data. You will be able to identify where names have been redacted in the released document.

Question 7: If the WCC is revised to account for long-term soil carbon losses post-planting, will this be applied to any existing projects? If so, which ones? If applied would this change occur to those projects awaiting all subsequent verifications over the project lifetime?

Response to your question 7: The answer to Q6 shows that the Woodland Carbon Code already accounts for any long-term soil carbon losses.

Question 9: Please can you provide the names and/or job titles of the staff with the WCC and Scottish Forestry who are responsible for proposing changes or revisions to the WCC, along with the names and job titles of staff with the WCC, Scottish Forestry and anyone else in the Scottish Government who are responsible for implementing or rejecting proposed changes or revisions to the WCC. 

Response to your question 9: Details of the staff involved in running the Woodland Carbon Code are provided in the governance section of the website here.

Where information is already publicly available, links to the relevant webpages have been provided. Under Regulation 6 (1) (b) of the EIRs, we are not required to provide you with information that is readily available online.

ANNEX A

REASONS FOR NOT PROVIDING INFORMATION

Personal data relating to a third party

An exception under Regulation 11(2) of the EIRs (personal information) applies to some of the information requested because it is personal data of a third party and disclosing it would contravene the data protection principles in Article 5(1) of the General Data Protection Regulation and in section 34(1) of the Data Protection Act 2018.

This exception is not subject to the ‘public interest test’, so we are not required to consider whether the public interest in disclosing the information outweighs the public interest in applying the exception.

Information publicly available

Under Regulation 6 (1) (b) of the Environmental Information (Scotland) Regulations 2004 (the EIRs), Scottish public authorities are not obliged to provide information if it is already publicly available and easily accessible, for example, online.

This is an absolute exception and is not subject to the public interest test.

Intellectual property rights – copyright

Regulation 10(5) (c) of the Environmental Information (Scotland) Regulations 2004 (the EIRs) allows aScottish public authority to withhold environmental information if its disclosure would or would likely cause substantial prejudice to intellectual property rights, including copyright.

Two documents listed in response to question one were identified during the search and used as sources when compiling the answers to the request; these documents were subsequently withheld in full under Regulation 10(5)(c) of the Environmental Information (Scotland) Regulations 2004 (the EIRs).

This exception is qualified and subject to a public-interest test to determine whether the public interest in withholding information outweighs that of disclosure.

While we recognise that there is some public interest in transparency, openness, and accountability of public authorities, the public interest in maintaining the exception outweighs the public interest in disclosure. Disclosing copyright-protected information available for purchase and free of charge online, in bookshops, in academic databases or national libraries could cause potential financial and reputational harm to the public body, in this case, Scottish Forestry and Scottish Government, and consequently to the Scottish taxpayer.

Information not held at the time of the request

The Environmental Information Regulations (EIRs) apply to recorded information already held at the time of the request, and Scottish public authorities are not required to create new records to answer questions, even if an accountability gap exists.

Scottish Forestry did not hold the requested information at the time the request was received. Under Regulation 10 (4) (a) of the Environmental Information Regulations (EIRs), Scottish public authorities are not required to provide information that they do not hold at the time of the request, nor to generate new information.

This exception is subject to the ‘public interest test.’ Despite not holding this information, we have a statutory obligation to apply this test. Therefore, taking into account all the circumstances of this case, we have considered whether the public interest in disclosure outweighs the public interest in applying the exception. We recognise that disclosing information not held at the time of the request, or creating information to respond to information requests, could impose an unjustified burden on public resources. Taking account of all the circumstances of this case, we have found that, on balance, the public interest lies in favour of upholding the exception.

About FOI

The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at https://www.gov.scot/foi-responses.

EIR 202600513712 - Information released - Annex B

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