Dr. Frank O'Mara:

Hedgerows are an important feature of Irish landscapes. We have quantified the length of hedgerows in the country and the total is somewhere of the order of 650,000 km. They are a huge part of our landscape when one considers that the average field size is somewhere around 2.5 ha and most field boundaries, as committee members know, are hedgerows. They have a role in carbon sequestration and storage. There is a difference between storage and sequestration. Our hedges store a lot of carbon in the woody biomass, the material above ground, and there is also quite a bit of carbon in the rooting system and so on underground. From the point of view of sequestration, the additional carbon that is added is of real interest. That can be in the form of planting additional hedgerows or managing our existing hedgerows to allow them to accumulate some more material or biomass. In other words, that would involve making them a little bushier than they currently are while still maintaining their shape and making sure they are effective as stock barriers and shelter belts.

As I said, we have quantified the length of hedgerows and we are now involved in research to look at the amount of carbon that is stored both above and below the ground. While we know that additional hedgerows or allowing the existing ones to get bulkier will add extra carbon, we are also trying to quantify more exactly how much extra carbon might be stored from the way we manage our hedges.

This is a very active area of work and we hope to have the results of it very soon.