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Country Land and Business Association


Country Land and Business Association

The CLA is the membership organisation for owners of land, property and businesses in rural England and Wales.


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Savills is a global property company with a dedicated Rural division. Employing over 180 professionals, operating out of more than 24 UK offices, we aim to give our clients the best of UK rural experts, able to advise on all aspects of rural property.


CALM, Carbon Accounting for Land Managers, is the first, fully-free, business activity-based calculator showing the balance between annual emissions of the key Greenhouse Gases (GHGs)and carbon sequestration associated with the activities of land-based businesses.

The calculator measures emissions of carbon dioxide, methane and nitrous oxide from a land-management business and any carbon which is stored in soil and trees. 

The emissions come from:

  • Energy and fuel use,
  • Livestock,
  • Cultivation and land-use change,
  • The application of nitrogen fertilisers and lime.

These are balanced against carbon sequestration in soil and trees.

The calculator also assesses the impact of Environmental Stewardship options. This is calculated as a partial budget to estimate what would be saved following entry into Stewardship or what has been saved where the business is already in the scheme. It is not a measure of carbon capture (sequestration) but the annual change in emission pre and post entry, although some of the changes, such as new grass margins on arable land do sequester carbon (where they remain in place).

Understanding the carbon balance of a business is a vital first step towards thinking about management decisions that may have some mitigating effect on climate change by reducing GHG emissions.

The calculator has been updated with the latest UK National Inventory Report (1990-2006) data published in April 2009. This may change the output from previously entered data.

The "further reading" screen provides more information and web links to the references and sources used in the construction of the calculator.

"CALM is an excellent first step, and offers a useful tool for land managers" Professor Gareth Edwards-Jones, Professor of Agriculture and Land-use studies at the University of Wales, Bangor. (CALM peer reviewer)


  • Step 1 - Get your data together. You will need physical data for crops, stock and energy use.
  • Step 2 - Select "Login" on the top menu bar to enter your name and secure password.  This will not appear if you are already logged in, in which case go straight to step 3.
  • Step 3 - Select "Calculations" (on menu bar) to enter your farm details and then a calculation for the farm. If you have previously used the calculator you may select an existing farm profile by clicking on it.
  • Step 4 - Create a calculation for the farm selected. If you have already created calculations for the farm selected you may also modify, copy or use any of these, also by clicking on the description.
  • Step 5 - Select the type of assessment (Whole farm, forestry, stewradship)
  • Step 6 - Enter data in the input screen. For more guidance visit the Help page.
  • Step 7 - When finished click "Report" on the menu at the top of the screen and choosing the output format you require.
  • Step 8 - Use the mitigation advisory notes, available from the reports section, to assess ways you can improve your carbon balance.

All data is saved as it is entered. You can come back to it later and add to it or copy it or clone the data for subsequnet modification to test "what if" assumptions.  Where (some) data is entered under a particular section heading make sure that values are entered into any other related inputs on screen for that section even if zero (e.g. where a crop tonnage produced is entered and no straw is moved from the farm, enter zero for the straw).

The site is secure and data is only accessible to the user. Additional notes can be found on the Help page.