Sir, – ‘Don’t eat meat’ – someone shouted it and everyone followed without a thought.

But, the opposite is true. Let us look at 10 molecules of CO2 in the atmosphere. They waft pass some grass, the grass takes them in and with the magic of photosynthesis, takes the carbon atoms, makes sugars and releases oxygen.

Of those 10 carbon atoms, seven will go on to make a bit of the carbohydrate and protein of a leaf, three will go on to make a bit of root, and subsequently become part of soil biology.

Those seven ‘leaf’ carbon atoms get eaten by a grazing ruminant, four of those carbon atoms are converted to protein (50% carbon) by the magic of the rumen. Two of these carbon atoms make dung, which lands on the ground providing food for a wonderful variety of lifeforms, in turn providing nourishment for the soil, for birds and much more.

One carbon atom is left and this becomes the ‘emission’, which is negligible compared with the CO2 removed by the grass.

Back to the four atoms in the animal’s protein. We eat it. When we are young, it builds our bodies and is stored. When older, it is used for repairs. What we do not use ends up in the loo, from there to the sewage works where it can easily be trapped and stored.

Taking a look at planted woodland. The soil is ridged to make a drained weed-free strip to plant the wee tree. It grows and grows, and after 10 years covers the ground – 100% leaf area index. At this stage it can trap as much CO2 as grass, but the grass has been trapping CO2 for 10 years already.

The trees grow for another 20 to 30 years, not allowing light to the soil creating an almost sterile acid environment and building wood – only 45% carbon unlike protein!

Trees are then harvested, baring the soil and allowing erosion and oxidation of the soil – for another 10 years until full cover is again achieved.

So much of Scotland is only suitable for grass and thank goodness, Thanks to ruminants, it can produce wonderful food for us and also trap carbon to save the planet.

Many parts of the world are dry and arid – but with skill and great dreams, it could be cooled using solar panels for shade during the day and producing a little moisture from condensation during the night, enabling grass to be grown for livestock and an income from electricity sales plus carbon capture from all that CO2 taken in by grass.

We see politicians wringing their hands with no idea how to remove CO2 from the atmosphere – it is so obvious, nature does it all the time for free!

Eat meat, grow grass and save the planet.

Robert Johnstone

Balaclava,

Island of Islay.