Carbon Footprinting

At Organic Arable we see the importance of supporting our members to beginning the journey of annual carbon footprinting. In fact, one day, in the not too distant future it is likely to be an essential part of running a farm business and we are already starting to feel a pressure from our buyers to quantify the carbon emissions from the farms who supply them. The day may even come when this data is a requirement of selling grain and who knows, a net zero or carbon negative farm may even receive a premium. Farm subsidies may also be linked to carbon emissions. With all this in mind we cannot underestimate the importance of encouraging you all to take part in this process, particularly as we are offering support to complete the footprinting using Organic Arable's very own  Farm Carbon Toolkit Calculator (

We are now making good progress in completing the calculator with our members and we would like to encourage you to take part in this process if not done so already and if you haven't got a date in the diary with either Andrew or myself to introduce you to the tool. I am happy to say filling out the data is not nearly as onerous as a first glance at the tool may suggest and there are key places to focus that will have the biggest impacts on both your emissions and sequestration. The calculator is currently taking around two hours to bring to near completion with a bit of extra time to finesse and improve the accuracy of the data. There is plenty of estimation and whilst no-one would claim the tool to be perfect, it is a good starting point on the road to annual carbon footprinting your businesses. 

One area that it has become increasingly apparent of the importance, is in long term, consistent monitoring of soil carbon. There are farms that may have doubled their soil organic matter (SOM)  since conversion to Organic, but without the data to support this, the carbon sequestration associated with this build up in SOM cannot be accounted for and will not count towards the offset of emissions. In fact if long term  soil sampling has been conducted it would help to show Organic farming can be considered "regenerative", but without measuring, monitoring and proving the upward trends since conversion, it can't prove that. A note on this: whilst most soil organic matter testing has been using loss on ignition (LOI) as the method which is cheaper but also less accurate than measuring using the Dumas method should be considered. It has to be said that LOI is most likely to be inaccurate on soils high in chalk and clay where it overestimates soil organic carbon. In order to make use of long term data it is imperative to use a consistent method. You cannot convert between LOI and Dumas. However, I would encourage farmers to start using the more accurate test as quickly as possible, and to perhaps consider a period of transition in which you are collecting both LOI and Dumas data on the same fields. The calculator works on trends in SOM levels so a single time point or a steady state will not give you a sequestration value. Soil analysis results are also highly variable so two or three time points may also not be reliable, and you may need several years of testing to establish the true, overall trend in SOM (think of it like the volatility in the stock market in the short term compared to the overall growth longer term). Signing up to the SFI will help to cover the costs of soil sampling in the short term as a potential transition in testing takes place.

It also has to be said that whilst the tool continues to use the metric of GWP100 it is still overestimating the global warming potential of the greenhouse gas methane (CH4) which serves to make livestock farming more carbon producing than it is in reality. Hopefully the tool will start using GWP* as a more accurate time horizon, which does take account of the short lived nature of methane. The biggest emissions by far have been from livestock enterprises but fuel usage has also been contributing a significant proportion too. We have seen some farms close to carbon neutral and some farms that are even carbon negative but these farms have large areas of woodland.

Please get in touch if you're keen to carbon footprint and haven't yet signed up to it.