Hedgerows' important role in climate-change mitigation 'overlooked'

The role of Ireland’s 700,000km of hedgerows in achieving our climate targets has been overlooked in the design of the Common Agricultural Policy (CAP) Strategic Plan (CSP).

Hedgerows Ireland has called on the Department of Agriculture, Food and the Marine (DAFM) to change that and to ensure that good hedgerow management becomes a key feature of CAP 2023-2027.

Hedgerows are a “hot topic” in carbon research circles – internationally and here in Ireland – according to Dr. Alan Moore of Hedgerows Ireland.

The focus is on how the size and biomass of these features can be accurately determined with a view to maximising their contribution to carbon neutrality by 2050, he explained.

Ireland has approximately 700,000km of hedgerows with the potential to trap significant carbon dioxide, as well as address biodiversity and species loss.

“But only if hedgerows are in good condition,” Dr. Moore told Agriland.

He explained that only one third of our hedgerows currently fit into this category.

“Small changes in hedge-cutting techniques and regimes could double or treble carbon sequestration according to recent research, he said.

Irish research
Precise measurement of these values is the subject of ongoing research by Teagasc in conjunction with the Environmental Protection Agency using LiDAR (Light Detection and Ranging) which will soon allow accurate figures to demonstrate on-farm trapping of carbon by hedges.

“Allowing hedges to grow to 2m or 3m in height instead of 1-1.5m would make a big difference, and further changes such as three-year-rotation cutting regimes or side-cutting-only techniques would multiply the benefits,” he said.

While the CSP references hedgerows under Good Agricultural and Environmental Conditions (GAECs), it goes no further than to reiterate the ban on cutting these features during bird-breeding/bird-rearing season.

Hedgerows Ireland has engaged in the CSP consultative process and has requested that it is amended so that the references to hedgerows are explicit and feature in relevant Pillar I and II schemes.

“We want the wording of the first of the Pillar I Eco Schemes to include a basic requirement that hedgerows are left to a minimum of 2m in height and either side cut only, or not cut for the duration of the scheme,” explained Dr. Moore.

More advanced measures of hedgerow quality would then be integrated into the Pillar II agri-environmental schemes.

“This would assess such elements as hedgerow trees, species diversity, soil organic carbon and biomass values,” he added.

The finer details are as follows:

Pillar I Eco Scheme I
Non-productive areas and landscapes: That existing hedgerows be retained and maintained with either side cutting only, or no cutting of internal/non roadside boundaries. Minimum height 2m;
Under Pillar II Agri Environmental Climate Measures Tier 3
Boundary Actions: Results-based payments for hedgerows using recognised measures of quality (height, width, species, diversity etc.).

“In addition to carbon and biodiversity values, hedges reduce flooding and soil run-off, filter pollutants and nutrients, provide shelter and shade and define ancient and historic landscapes.

“We have taken them for granted in the past, but apart from the UK and parts of France, hedgerows are largely unknown in Europe. Now is definitely the right time to value what is right under our noses,” Dr. Moore said.

Hedgerows Ireland has received support for its proposals from: