Hedgerows and carbon sequestration

Hedgerows and grassland make a positive contribution to climate stabilisation and biodiversity

Sir, – The plea from the prominent environmental bodies with regard to saving our hedgerows will surely strike a chord with many who cherish the Irish landscape and environment (Letters, February 3rd).

Indeed, looking out over our patchwork of small fields I have often asked myself the question as to whether the abundant hedgerows are valued and, in particular, whether they are taken into account when considering net carbon emissions. The answer, it seems, is not straightforward.

The carbon sequestration contribution of hedgerows and indeed grassland is not taken into account under agriculture in the Climate Action Plan. This has potential to give a distorted impression as to carbon emissions under the agriculture heading.

Hedgerows and grassland are considered under a separate heading “Land use, land-use change and forestry”. But this is a very broad land-use category which includes grasslands, wetlands, forestry and the marine. Surprisingly, perhaps, these land uses in total are calculated as carbon emitters.


At first glance, this suggests that farmland (including hedgerows) do not contribute to carbon sequestration or offset emissions from farming.

But how the emissions and sequestration are measured reveals a lot.

For grasslands the amount of carbon sequestered each year (which can be up to four tonnes per hectare) is not accounted for in the calculation. Instead, the amount allowable is the “additional sequestration” that occurs due to “management changes”. In practical terms the allowance is the difference between the actual carbon performance of the cultivated grassland and a baseline output before cultivation. But, if we left all the land uncultivated there would be no agriculture!

Hedgerow contributions are to be measured against a 2005 baseline. But since we have no idea what the baseline was in 2005, we cannot measure the contribution from hedgerows.

State-owned bogland is a very high-carbon emitter which drags the figures down. The average farmer can have no effect on this.

Grassland on drained organic soils is a high emitter.

These are the lands which were improved in the past with massive State aid and encouragement.

The net effect of the “Land use, land-use change and forestry” heading is to give the impression that farming is an environmentally unsustainable activity and that the average farmer is somehow at fault.

While I welcome the proposal that farmers should be given encouragement and financial incentive to maintain their hedgerows, I also think that we need to re-evaluate how the carbon emission figures are calculated and more importantly how they are presented in order to recognise the positive contribution which hedgerows and grassland are making to both climate stabilisation and biodiversity. This would be far more productive than seeking to reduce hedgerow removal limits or increasing penalties. – Yours, etc,



Dublin 14.