A new report published by the Department of Agriculture shows that over half of Irish forestry (54%) has now become a small source of greenhouse gases as it emits more carbon into the atmosphere than it sequesters each year.

According to National Forestry Accounting Plan 2021-2025, managed forestry land in Ireland, which includes forests managed by Coillte and farmers that are over 30 years old after 2021, has transitioned from being a carbon sink over the last decade to a source of carbon emissions in 2020.

The forestry report forecasts that managed forestry in Ireland will emit an average of 140,000t of C02 equivalent every year from 2020 to 2025. The reason this forestry is now emitting more carbon than it is capturing from the atmosphere is due to the maturing and harvesting of the trees, as well as the loss of carbon from the soils in which the trees are planted.

Peat soils

Forestry planted on peat soils heavy in organic matter is a typical example of this, where the drainage of the soil for planting and the subsequent aeration of the soil by the new trees leads to significant CO2 losses from the carbon-rich peat soil.

Over half of all forestry in Ireland (54%) is deemed to be managed forest land as it is over 30 years old after 2021. The remaining 46% of forestry in Ireland is known as afforested land and comprises forest cover and trees that are less than 30 years old. These trees remain a major carbon sink and typically sequester between 4m and 5.5m tonnes of CO2 equivalent every year, which more than offsets the small sourse of carbon emissions from managed forestry.

When taken as a whole, the entire forest estate in Ireland removed an average of almost 4m tonnes of C02 equivalent between 2007 and 2016.

However, the National Forestry Accounting Plan forecasts that managed forests will begin to emit more and more CO2 over the coming decades as trees are harvested. Annual CO2 emissions from managed forestry is forecast to peak at close to 3m tonnes of CO2 equivalent by 2035.

The report forecasts that the net impact of this rise in emissions from managed forestry land will almost totally offset the amount of carbon being captured out of the atmosphere every year by the 46% of afforested land in Ireland.

Forestry in Ireland

Since the foundation of the State, forest cover in Ireland has grown from 1.4% of the total land area to the current rate of 11% today.

In total, over 770,000ha (1.9m acres) of land in Ireland is afforested. Over 300,000ha (740,000 acres) of this land has been afforested in Ireland since 1990. The majority of the land afforested has been privately-owned agricultural land.

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