Scottish Forestry's Carbon Code Calculations: EIR Review

Information requested

Original request 202600512427

On 19 October 2021, Dr Pat Snowdon (Head of Economics and Woodland Carbon Code) was one of several witnesses attending the House of Lords Science and Technology Committee – Nature-based solutions for climate change. The transcript for this session is provided with this FOI request.

In response to question 51, Dr Snowdon states ‘we have modelled the Woodland Carbon Code on the world’s leading global standards such as Verra, the Verified Carbon Standard, and the Gold Standard, so it has the key components of a high quality standard such as measures for permanence, additionality, transparency through the use of a carbon registry, and independent third party validation and verification. These are the central components of a good-quality code’.

1. Verra and other ‘global standards’ may use a range of methodologies which may also be updated over time. Which specific methodologies from these global standards were used for modelling the Woodland Carbon Code (WCC)? Please provide the specific methodologies (and their mathematical/scientific workings) used.

2. Did staff working for the WCC and/or Scottish Forestry (and/or other Scottish Government staff) ensure that due diligence measures were taken to assess the credibility of the global standards used to model the WCC? Please provide all information (if any) to show that due diligence measures were made.

3. Was the decision by staff and/or advisors working for the WCC/Scottish Forestry to adopt the temporary sequestration of carbon (with buffers) on site from commercial forestry (by calculating the long-term average stock of carbon) based on a methodology or methodologies provided by one or more of these ‘leading global standards’? If so, what were the methodologies used? Please provide the specific methodologies, and their mathematical/scientific workings used to show that the long term average stock of carbon on site was used to determine carbon sequestered, if not already provided under point 1 above.

4. The WCC claims there are no leakage effects due to the 1967 Forestry Act and agricultural regulations. It is assumed leakage effects (in this case) refers to carbon emissions occurring from

• (a) trees being cut down for agricultural production and
• (b) agricultural intensification of existing agricultural land (both measures being to compensate for loss of food supply from planting new woodlands). Does the WCC state/mean that there are assuming no leakage effects occur in the UK only, or there are no leakage effects at an international level?

5. Was this assumption that planting new woodlands in the UK have no leakage effects derived from one or more methodologies used in the various ‘global standards’ previously mentioned by Dr Snowdon? If so, please provide what these methodologies were. Also please provide all economic forecasting and other claimed evidence (if any) that shows no leakage effects occur.

6. In determining how the WCC was/is calculated, did the WCC/Scottish Forestry staff investigate or research the hypothetical lifecycle (carbon/greenhouse gas) emissions of the (range of) timber products when taken off-site? It is understood harvesting emissions are already considered when computing the long-term average stock of timber on site. If yes, did the WCC/Scottish Forestry consequently establish that these lifecycle emissions meant the alleged projected quantity of long term carbon sequestration as computed by the WCC calculator for new commercial (harvested) woodland creation sites was therefore untrue?

7. Scientists and others have pointed out that the carbon sequestered by trees (those planted for commercial purposes) is only temporary, as all the carbon sequestered is typically returned to the atmosphere over the lifecycle of the product. Furthermore, there will be emissions from activities such as transport, processing, manufacturing and distribution of the resulting timber products.

The quantity of these cumulative emissions (over indefinite, multiple harvest cycles) from these activities will reduce and eventually exceed the quantity of long-term stock of carbon sequestered on site from where the timber was harvested. It appears the WCC/Scottish Forestry decided to ignore the fact that the long-term stock of carbon on site would be reduced and eventually cancelled out by the emissions from consuming the resulting timber products. Was this decision to ignore lifecycle emissions due to the WCC/Scottish Forestry adapting one or more of the ‘global standards’ (or some of the methodologies within these standards) mentioned previously? If so, please provide the methodology or methodologies that was used to ignore lifecycle emissions. Alternatively, was the decision by the WCC/Scottish Forestry to ignore the impact of lifecycle emissions taken by its own staff/advisors?

8. It is understood that there is no requirement for companies that process the harvested timber off site (for the end product) to ‘compensate’ for their greenhouse gas emissions caused by their activities. However, even if there was an obligation to ‘compensate’ for these emissions by for example, ‘offsetting’ through acquiring carbon credits from a different, new commercial woodland creation scheme, there are also product lifecycle greenhouse gas emissions due to the new woodland scheme. Does the WCC/Scottish Forestry hold any information that shows mathematical and scientific proof that using carbon credits from a new commercial woodland creation scheme to ‘compensate’ for emissions from the lifecycle emissions of timber products leads to net removal of greenhouse gases from the atmosphere? The following questions/requests for information relate to governance and decision making by the WCC in determining how carbon sequestration calculations, methodologies and assumptions are approved and/or incorporated into the WCC calculator.

9. The WCC website states that the WCC has been in operation since 2011. Is it the case that since the original WCC calculator in 2011, estimated projected carbon sequestration was based on the long-term average stock of carbon in trees over harvesting cycles, such as up to 100 years?

10. Please could you identify all the individuals and their job titles within the WCC/Scottish Forestry (or predecessor organisations such as Forestry Commission Scotland) that were responsible for the original (version 1.0) of the WCC and the associated spreadsheet calculator.

11. It is understood the WCC and the associated spreadsheet calculator has been updated (currently at version 3). From 2011 up to this version, have there been any proposals by WCC/Scottish Forestry staff and/or WCC advisors to cease including the projected carbon sequestration attributable to the long-term temporary stock of commercial (harvestable) trees on site?

12. From 2011 up to version 3.0, has there been any communication from third parties to suggest, advise, or debate discontinuing the inclusion of projected carbon sequestration attributable to the temporary stock of commercial (harvestable) trees on site? If so, please provide all correspondence between Scottish Forestry and these third parties in relation to any possible suggestions, advice or debates to discontinue the inclusion of projected carbon sequestration attributable to the temporary stock of commercial (harvestable) trees on site.

13. Have the WCC and/or Scottish Forestry in the last six years written, or received any reports (published or unpublished) confirming that commercial conifer plantations do not permanently sequester carbon? If so, please provide these report(s).

14. Please could you identify all the individuals and their job titles within the WCC/Scottish Forestry that were responsible for the latest version (version 3.0) of the WCC and the associated spreadsheet calculator.

Response

I have now completed my review of our response to your request 202600512427 under the Environmental Information (Scotland) Regulations 2004 (EIRs).

I have reviewed our original response and concluded that the original decision should be modified in order to provide more clarity on the information already provided and provide newly found information from new searches carried out as part of this review.

Your initial questions in EIR request 202600512427 were:

1. Verra and other ‘global standards’ may use a range of methodologies which may also be updated over time. Which specific methodologies from these global standards were used for modelling the Woodland Carbon Code (WCC)? Please provide the specific methodologies (and their mathematical/scientific workings) used.

I am upholding Regulation 10(4)(a) of the Environmental Information Regulations (EIRs) (information not held) because you asked for specific methodologies used from ‘global standards’ for modelling the Woodland Carbon Code (WCC). Specific ‘global standard’ methodologies were not copied to produce the WCC but ‘global standards’ were researched in identifying good practice on which to base (or model) the development of the WCC.

Under Regulation 9(1) of the Environmental Information Regulations (EIRs) (advice and assistance) I will provide further context that may be of help. I am also providing 6 documents as part of this advice and assistance.

There have been major staff and organisational changes since the design phase of the WCC in the period up to launch in 2011, including the completion of forestry devolution in 2019. Staff leading the development of the Code between 2007 and 2011 have left the organisation. There is one current Scottish Forestry staff member who was involved at the time, but he does not have access to all the files that were created at the time.

However, the 6 documents found through the search for this review demonstrates that the Code of Good Practice (as the WCC was known at the time) aimed to follow best practice in carbon markets internationally. These include documents relating to the public consultation that was held in 2009 about the development of the Code of Good Practice. References are made in these to other standards, including the Verified Carbon Standard (VCS).

It should be noted that the development process involved research and discussions with experts and stakeholders about best practice in carbon markets, but the aim was to design a standard that could operate in the UK while being aligned with best practice, rather than to copy the detailed methodologies of other standards. For example, the UK has specific growing conditions, land-use patterns, legislative and economic structures which mean that the Woodland Carbon Code’s carbon calculator and the additionality test had to be designed to operate effectively in this UK context.

The essential point was that this should be done while adhering to best practice principles in carbon markets including permanence, additionality, transparency and independent validation and verification.

The Forestry Commission set up a Technical Working Group in 2008 comprising experts and practitioners in certification schemes and carbon projects. The group included a representative from Plan Vivo, an international standard for nature-based projects in climate and nature markets that has now operated for over 25 years. The group discussed the attached document on “Carbon Standard Methodologies and Potential Application in the UK Code (Final)” which formed part of the Forestry Commission’s research into how lessons from other carbon standards might be applied in the Code in the UK.

Regulation 11(2) of the EIRs (personal information) applies to 5 of the 6 documents being sent as part of this review 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 if the public interest in disclosing the information outweighs the public interest in applying the exception.

2. Did staff working for the WCC and/or Scottish Forestry (and/or other Scottish Government staff) ensure that due diligence measures were taken to assess the credibility of the global standards used to model the WCC? Please provide all information (if any) to show that due diligence measures were made.

I refer to the answer given under Q1 above. I have also provided the following information that underlines the status and reputation of the Woodland Carbon Code internationally.

• the Woodland Carbon Code is endorsed internationally by the International Carbon Offsetting and Reduction Alliance
•  the Code is currently going through the process of accreditation with the global standards body, the Integrity Council for Voluntary Carbon Markets (ICVCM). The Code has passed the ICVCM’s “completeness checks” which means that is contains the necessary components to be worthy of the full assessment under the ICVCM.
• The Woodland Carbon Code was named as a winner in the 2025 Bloomberg Philanthropies Local Leaders Climate Awards prior to the climate change COP in Brazil in November 2025.

If you have dissatisfaction with any element of data that was provided to you under the general response 202600515196 then you can provide this dissatisfaction as a separate email as this dissatisfaction will not be responded to as part of this EIR review.

3. Was the decision by staff and/or advisors working for the WCC/Scottish Forestry to adopt the temporary sequestration of carbon (with buffers) on site from commercial forestry (by calculating the long-term average stock of carbon) based on a methodology or methodologies provided by one or more of these ‘leading global standards’? If so, what were the methodologies used? Please provide the specific methodologies, and their mathematical/scientific workings used to show that the long-term average stock of carbon on site was used to determine carbon sequestered, if not already provided under point 1 above.

I am applying Regulation 10(4)(a) of the Environmental Information Regulations (EIRs) (information not held) because WCC/Scottish Forestry did not use a methodology or methodologies by one of these ‘leading global standards’.

Under Regulation 9(1) of the Environmental Information Regulations (EIRs) (advice and assistance) I will provide further context to help explain this further.

I am providing you with a link for the Woodland Carbon Code Template documents and tools | Woodland Carbon Code. The calculations are within the carbon calculator spreadsheet. The link provides the spreadsheets and guidance. The tab in the Carbon Calculator called “StandardProjectCarbonCalculator” shows the calculations that are made to estimate the number of carbon credits to be issued and includes deductions for any soil emissions.

Forest Research holds the data for the carbon models that underpin the Woodland Carbon Code carbon calculator. These models are based on scientific consensus and evidence from forest growth in the UK in recent decades. Scottish Forestry (and the other Forestry Authorities across the UK) has supported Forest Research to develop and enhance the science that underpins their carbon models.

An internet search has identified the VCS guidance that was applicable in 2011 (when the Woodland Carbon Code was launched) for calculating long-term average carbon stocks for forestry projects with harvesting. This contains tables with calculations. However, as noted in my response to Qs 1 and 2, the Woodland Carbon Code carried out its own calculations based on UK forest growth and forest carbon models developed by Forest Research. The Woodland Carbon Code carbon calculator spreadsheet here contains a tab called “clearfell max” which applies the long-run average ceiling that is applied to projects that involve clearfelling. Guidance is provided here (see p8) and worked examples including a clearfell example can be found here. Forest Research produced this document on the construction of the carbon look-up tables used by the Woodland Carbon Code in it carbon calculator although it does not describe the approach for calculating the long-term average carbon for clearfell projects. The carbon data for clearfell projects were provided by Forest Research. This publication by Forest Research discusses the calculation of long-term average carbon (see Appendix 1, for example p129) and shows that these are in the region of a third to half of the carbon for a non-felled management regime. This is consistent the Woodland Carbon Code guidance which states on p8 that “Long-term average carbon stock tends to be between 30% and 50% of the cumulative total carbon sequestered over one rotation.”

Further detail on long-term average carbon stocks is provided in this international report in which Forest Research was also involved (see Section 5 and Appendices 2 and 3).

4. The WCC claims there are no leakage effects due to the 1967 Forestry Act and agricultural regulations. It is assumed leakage effects (in this case) refers to carbon emissions occurring from (a) trees being cut down for agricultural production and (b) agricultural intensification of existing agricultural land (both measures being to compensate for loss of food supply from planting new woodlands). Does the WCC state/mean that there are assuming no leakage effects occur in the UK only, or there are no leakage effects at an international level?

The WCC does not claim that there are no leakage effects, and the WCC guidance states that projects should consider whether they will result in more intensive use of another area of land elsewhere in the UK. We cannot guarantee for example that there are no leakage effects at an international level. Equally, we do not have evidence to indicate that there are such effects due specifically to Woodland Carbon Code projects or that any such possible effects would be significant (defining “significant” as more than 5% of the project carbon sequestration over the duration of the project). It is important to note that woodland planting in the UK is focussed on less productive land. There are also multiple and complex factors affecting trends in agricultural production at a national and international level.

5. Was this assumption that planting new woodlands in the UK have no leakage effects derived from one or more methodologies used in the various ‘global standards’ previously mentioned by Dr Snowdon? If so, please provide what these methodologies were. Also please provide all economic forecasting and other claimed evidence (if any) that shows no leakage effects occur.

Regarding leakage in the UK, an answer has already been provided, through EIR 202600512427, on why this is unlikely in the UK. We do not have analysis or economic forecasts to confirm this. It is important to note that Woodland Carbon Code projects do not account for the reductions in Greenhouse Gas (GHG) emissions due to cessation of agricultural activities where woodland creation takes place. Although UK legislation protects semi-natural habitats, biodiversity and protects against deforestation, Woodland Carbon Code guidance states that projects should consider whether a project will result in more intensive use of another area of land elsewhere in the UK. A further consideration is the impact on farm productivity of planting trees and woodlands on farms. We are aware of cases where such planting has increased farm productivity and/or reduced risks to farm output, and Scottish Forestry has commissioned research (currently underway) to develop a more comprehensive evidence base.

I am applying Regulation 10(4)(a) of the Environmental Information Regulations (EIRs) (information not held) because no methodologies and economic forecasting and other claimed evidence is held.

6. In determining how the WCC was/is calculated, did the WCC/Scottish Forestry staff investigate or research the hypothetical lifecycle (carbon/greenhouse gas) emissions of the (range of) timber products when taken off-site? It is understood harvesting emissions are already considered when computing the long-term average stock of timber on site. If yes, did the WCC/Scottish Forestry consequently establish that these lifecycle emissions meant the alleged projected quantity of long-term carbon sequestration as computed by the WCC calculator for new commercial (harvested) woodland creation sites was therefore untrue?

The Woodland Carbon Code does not account for GHG impacts beyond the forest gate. However, such impacts are accounted for in the different sectors in the UK GHG Inventory (including transport). There is evidence that the use of wood products both stores carbon (for the lifetime of the product) and can provide substitution benefits where timber replaces other materials whose production and use incurs higher levels of emissions. More detail can be found on the Forest Research website here, including a report commissioned by the Woodland Carbon Code team on the carbon benefits of wood products, material and fossil fuel substitution (see Chapter 4 on p19 in particular).

7. Scientists and others have pointed out that the carbon sequestered by trees (those planted for commercial purposes) is only temporary, as all the carbon sequestered is typically returned to the atmosphere over the lifecycle of the product. Furthermore, there will be emissions from activities such as transport, processing, manufacturing and distribution of the resulting timber products. The quantity of these cumulative emissions (over indefinite, multiple harvest cycles) from these activities will reduce and eventually exceed the quantity of long-term stock of carbon sequestered on site from where the timber was harvested. It appears the WCC/Scottish Forestry decided to ignore the fact that the long-term stock of carbon on site would be reduced and eventually cancelled out by the emissions from consuming the resulting timber products. Was this decision to ignore lifecycle emissions due to the WCC/Scottish Forestry adapting one or more of the ‘global standards’ (or some of the methodologies within these standards) mentioned previously? If so, please provide the methodology or methodologies that was used to ignore lifecycle emissions. Alternatively, was the decision by the WCC/Scottish Forestry to ignore the impact of lifecycle emissions taken by its own staff/advisors?

I am no longer relying on Regulation 10(4)(a) Environmental Information Regulations (EIRs) (information not held) and providing the following link to a report commissioned by the Woodland Carbon Code team. This report shows that the carbon lifecycle of wood products has been examined carefully by the Woodland Carbon Code team.

I refer to the information and reports provided to Q6. Recent work by Forest Research here considers the life cycle GHG impacts of the timber and wood products supply chain – Figure 2.1 on p8 provides a diagrammatic explanation of the scope of the work and section 2.12 examines the cross-sectoral impacts of wood products. An important finding of the work is to compare the GHG impacts of using wood products to those of using other materials/products (termed substitution effects). This is a crucial point in determining the GHG impacts of manufacturing and using wood products. P32 explains how the “displacement factors” used to assess substitution effects are calculated and shows that these factors are net of the emissions generated in the manufacture of wood products.

Under the terms of regulation 6(1)(b) we are not required to provide you with information that is already publicly accessible to you.

12. From 2011 up to version 3.0, has there been any communication from third parties to suggest, advise, or debate discontinuing the inclusion of projected carbon sequestration attributable to the temporary stock of commercial (harvestable) trees on site? If so, please provide all correspondence between Scottish Forestry and these third parties in relation to any possible suggestions, advice or debates to discontinue the inclusion of projected carbon sequestration attributable to the temporary stock of commercial (harvestable) trees on site.

I am upholding Regulation 10(4)(a) Environmental Information Regulations (EIRs) (information not held) as a further search was carried out as part of this review and no information was found regarding communications between Scottish Forestry and third parties to suggest, advise, or debate discontinuing the inclusion of projected carbon sequestration attributable to the temporary stock of commercial (harvestable) trees on site.

As indicated above, the Woodland Carbon Code does not account for emissions and removals beyond the forest gate and, for the reasons given in the answers above (for example, Q7) this means that the carbon storage and substitution effects are not considered.

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 202600515988 - Information Released - Documents

File type

PDF

File size

3.5 MB