Mr. Gerard Murphy:

I am not a scientist and this area can be complex. National statistics have been produced in terms of the Kyoto Protocol for carbon stock in different areas. The question concerning species is a good one. The rate of carbon sequestration depends on factors such as soil type. For example, peatlands will hold more sequestered carbon. There are also factors such as age and species. For instance, in the early years faster growing species like spruce will sequester more carbon. However, because there is a longer rotation period broadleaves tend to capture it over a longer period. It depends on at what stage one measures the rates of carbon sequestration. I am not aware of statistics for hedgerows, but we need to look at all of the different sources in accounting for total carbon produced. They tend to look at forests - above and below the ground and what is captured in the soil. That is my understanding of how carbon is measured.