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2.6 Monitoring

Monitoring Plan

Each project shall have a monitoring plan in place before validation.  Monitoring will enable the project to quantify and document the progress of carbon sequestration as well as ensure that the project is being managed to the UK Forestry Standard.

The monitoring plan shall contain details of how tree stocking density and carbon stocks will be assessed throughout the duration of the project, and outline how the Year 5 Survey Protocol or other Carbon Assessment Protocol method will be applied. The details shall include;

  • The assessment protocol(s) to be used
  • The frequency of monitoring
  • The sampling frequency (ie the number of plots)
  • Who will undertake the monitoring (project member or contract)
  • How the data will be reported and quality assured.

The monitoring plan shall also set out what monitoring is being undertaken to ensure that the project remains managed to the requirements of the UK Forestry Standard and the supporting Guidelines.  


When to monitor

Projects shall be monitored 6-12 months (but no more than 12 months) prior to each verification due-date to demonstrate successful woodland establishment initially and assess actual tree growth and carbon sequestration rates.  It is necessary to begin monitoring at this time to allow sufficient time for verification prior to the verification due-date. 


What to monitor

Monitoring at year-5
The first verification due-date of more recent projects will be 5 years after the start date (For those projects validated since July 2013 who used version 1.2 of the Code or later). For projects validated earlier, the timing of first verification due-date may differ.

The purpose of monitoring at year 5 is to ensure that the site has been suitably stocked and established (as set out in the PDD) and that the trees/ site are in good health with the potential to grow and sequester carbon as predicted.  

The Survey Protocol for WCC Project at Year-5 sets out requirements of the stratified sample plot survey.  It assesses:

  • Tree stocking density through number of seedlings and saplings of each species
  • Actual species mix
  • Tree health, tree damage, weed growth and tree protection (shelters/fencing)

The WCC Year 5 Data Collection and Calculation Sheet provides template sheets for data collection as well as a summary sheet which calculates stocking density from the results of the field survey.

Monitoring at subsequent assessment periods.
Verification due-dates for subsequent assessments will be 15 years after the project start date and then 10-yearly up to the project end date.  Thus monitoring of projects should start 6-12 months prior to each verification due-date. 

For subsequent assessments more detailed surveys of established trees will be required,  involving the collection of mensuration data.   Approved methodologies currently available for mensuration surveys are outlined in the Carbon Assessment Protocol.  

Future developments in remote sensing techniques may reduce the requirement to undertake plot based assessments. Appropriate methods for carbon related woodland assessments shall be set out in the WCC Carbon Assessment Protocol and kept under review.


Who can undertake the assessment?

The survey can be carried out by a suitably experienced landowner, project developer or independent third party.  The verification body will always visit the site at the year 5 verification but will do so on a risk-based approach for subsequent verifications.  Monitoring carried out by an independent third party could be less likely to require a field visit, however project developers should contact their chosen Verification Body to check the suitability of and independent surveyor prior to carrying out the survey.


The Carbon Assessment Protocol

5 Methods to estimate Volume:  The Protocol details 5 different methods of measuring the volume of timber (and therefore mass of carbon) in a woodland.  It also helps you to decide which method should be used for a particular woodland or situation:

  • Method A:  Felling of sample trees.  Whilst this is likely to give the most accurate results, it is not likely to be used in practice.
  • Method B:  Broadleaves 
  • Method C:  Conifers
  • Method D:  Pure even aged stands where measuring tree height is problematic
  • Method E:  Small woodlands (less than 1.25ha)

How to measure carbon:  For each method the protocol takes the user through a number of steps to enable the final calculation of whole-tree carbon estimates:

  • Deciding upon the method to use
  • Defining the area to be assessed
  • Dividing the woodland into 'similar' areas (stratifying your woodland)
  • Deriving a tree stem volume estimate
    • Deciding what size and how many plots to assess
    • What to measure (diameter, height etc)
    • How to record measurements
  • Estimating a whole tree volume
    • Adding in estimates for the volume of foliage
    • Adding in estimates for the volume of roots and stump
  • Converting the volume estimates to Carbon Dioxide equivalents

The science behind the protocol:  The methods of calculating the tree stem volume are detailed further in the Forest Mensuration Handbook.  The methods of estimating the mass of carbon from the tree volume are given in The Carbon Content of Trees and other Forestry Commission publications such as Forests, Carbon and Climate Change: the UK contribution


Verification of Projects

See Stay Certified - Verification.


Future Developments

  • We will develop a soil carbon assessment protocol
  • We will continue to investigate the potential for using less intensive methods of carbon assessment and look at alternative methods for monitoring carbon stocks in woodlands, for assessments from year 15 onwards.


Last updated: 8th March 2016