Ecosystem Condition Accounts - Forests and Woodlands 2024

Condition Accounts

Condition accounts record the condition of ecosystems in terms of selected characteristics at specific points in time. Over time, these accounts can be used to examine changes in condition, and provide information on the health and function of ecosystems and their capacity to provide ecosystem services.

The CSO has further developed its methodology for the development of condition accounts since the publication of Forests and Woodlands 2012-2022, and has included four additional condition indicators, alongside statistics on deadwood and tree cover density using updated methodologies, to provide a more comprehensive view of the condition of forests and woodlands. The condition indicator variables have been compiled and organised according to the System of Environmental-Economic Accounting - Ecosystem Accounts (SEEA-EA) Ecosystem Condition Typology (ECT), which together offer insight into the condition of these ecosystems based on water availability, carbon storage, forest structure, timber resources, disturbance, and the surrounding landscape.

Based on the condition indicator variables selected, Ireland's Forest & Woodland ecosystems show a trend of increasing condition over the three reference years. Four of the indicators show an increase between 2018 and 2024: Normalised Difference Moisture Index (NDMI) increased by 8.3% to 0.39, Tree Cover Density increased by 3.6% to 55.3%, Growing Stock Volume increased by 21.6% to 188.4 m³ per hectare, and Landscape Naturalness showed a small increase of 0.8% to 26.8%. Two showed no change: Normalised Difference Vegetation Index (NDVI) remained at 0.78, and forest damage was variable year on year but was 970 hectares in 2018 and 980 hectares in 2024. Two showed a decrease: soil organic carbon decreased by 0.9% to 133.5 tonnes per hectare and deadwood decreased by 11.4% to 10.9 m³ per hectare (Table 2.1).

In the following sections, each condition indicator variable is explored in more detail.

Table 2.1 Ecosystem condition accounts for Forest & Woodland 2018 - 2024

Group	Class	Condition Indicator	Measurement Unit	2018	2021	2024
Abiotic ecosystem characteristics	Physical state	Normalised Difference Moisture Index (NDMI)	index (-1 to 1)	0.36	0.36	0.39
	Chemical state	Soil Organic Carbon Stock (to 30cm depth)1	tonnes/ha	134.7	..	133.5
Biotic ecosystem characteristics	Structural state	Tree Cover Density2	%	53.4	55.7	55.3
		Deadwood1, 2	m3/ha	12.3	..	10.9
		Normalised Difference Vegetation Index (NDVI)	index (-1 to 1)	0.78	0.77	0.78
	Functional state	Growing Stock Volume	m3/ha	154.9	175.6	188.4
		Forest Damage	thousand hectares	0.97	0.18	0.98
Landscape and seascape characteristics	Landscape and seascape	Landscape Naturalness	%	26.6	26.6	26.8
1 Data for these indicators were taken from the National Forest Inventory; 2017 data were used for the reference year 2018; 2022 data were used for the reference year 2024.
2 Part of the reporting required for Ecosystem Condition Accounts under Regulation (EU) 691/2011.
.. no data available.

Extent of Ireland's Forest & Woodland ecosystem

Total forest extent increased from 827,600 hectares in 2018 to 834,200 hectares in 2024 (Figure 2.1, Table 2.2). Looking at different types of Forest & Woodland, Plantations accounted for the largest proportion, covering 591,800 hectares in 2018 (71.5% of Forest & Woodland), 593,500 hectares (71.2%) in 2021 and 597,400 hectares (71.6%) in 2024. Broadleaved Deciduous Forest was the next largest proportion, which increased from 145,900 hectares (17.6%) to 153,300 hectares (18.4%) between 2018 and 2024. Coniferous Forest, Mixed Forest, and Transitional Forest & Woodland Shrub each accounted for smaller shares, covering 3,700 hectares (0.4%), 51,100 hectares (6.1%), and 28,700 hectares (3.4%) in 2024. For more on Ireland's ecosystem extent accounts, see Ecosystem Extent Accounts 2024.

Abiotic Ecosystem Characteristics - Physical State

Normalised Difference Moisture Index (NDMI)

The Normalised Difference Moisture Index (NDMI) is a measure of the water content in plants, with low or negative values indicating water stress and high values indicating no water stress. For Forest & Woodland, the mean NDMI for all types of forest was 0.36 in 2018 and 2021, increasing to 0.39 in 2024 (see Figure 2.2, Table 2.3). This shows that more water was present in the tree canopies in 2024 compared with 2018 and 2021.

Looking at different types of Forest & Woodland, an increasing trend was evident in all types. Plantations were the only type to show a slight decrease in 2021 before increasing again in 2024. In 2024 Broadleaved Deciduous Forest had the lowest NDMI (0.30) closely followed by Transitional Forest & Woodland Shrub at 0.31, while Coniferous Forest and Mixed Forest were both 0.36. Plantations had the highest NDMI value of all types for all years, and in 2024 it was 0.42. NDMI measures water content in the tree canopies, and this is influenced by the density of the forest type as well as the type of leaves; Broadleaved Deciduous Forest is dominated by trees which lose their leaves in winter, and generally has a more open canopy than other types of forest, and so the lower NDMI reflects this. Overall, the NDMI condition indicator variable suggests that Forest & Woodland ecosystems are in increasingly good condition when it comes to water availability, as indicated by increased water content in the tree canopies.

Abiotic Ecosystem Characteristics - Chemical State

Soil Organic Carbon

The soil organic carbon content (to 30cm depth) decreased from 134.7 tonnes per hectare in 2018 to 133.5 tonnes per hectare in 2024, an overall reduction of 1.2 tonnes per hectare. This needs to be considered along with the increase in forest area over this time period, however, with the total quantity of soil organic carbon rising from 103,701 tonnes in 2018 to 107,987 tonnes in 2024 (Table 2.4). High carbon stocks improve soil structure, water retention, and nutrient cycling, so a decrease in soil carbon content can be linked with decreased forest soil condition. 

Biotic Ecosystem Characteristics - Structural State

Tree Cover Density

Tree cover density for Ireland's Forest & Woodland increased between 2018 and 2024, rising from 53.4% to 55.3%, indicating an overall increase in canopy cover (Figure 2.3, Table 2.5).

Looking at different types of Forest & Woodland, results varied by forest type. Coniferous Forest increased from 58.2% in 2018 to 60.2% in 2021 before decreasing to 58.4% in 2024. Mixed Forest increased from 59.3% in 2018 to 61.0% in 2021 before declining to 60.4% in 2024.  Plantations increased from 55.9% in 2018 to 59.0% in 2021 before decreasing to 57.9% in 2024. Transitional Forest & Woodland Shrub showed an opposite trend, firstly decreasing from 23.2% in 2018 to 22.4% in 2021 before increasing to 30.3% in 2024. In contrast, Broadleaved Deciduous Forest declined marginally from 48.5% in 2018 to 48.3% in 2021, remaining unchanged at 48.3% in 2024.

Increased tree cover density is associated with increased ecosystem condition and capacity to provide ecosystem services, e.g. the Air Filtration service. Overall, the results suggest a modest increase in forest condition as measured through tree cover density, although change differed between forest types.

Deadwood

The total deadwood volume per hectare decreased from 12.3m³/ha in 2018 to 10.9m³/ha in 2024 (Figure 2.4, Table 2.6). This trend was not evident in all categories of deadwood however, and while lying deadwood decreased from 7.9m³/ha to 5.4m³/ha, standing deadwood increased from 4.4m³/ha to 5.5m³/ha. Deadwood in a forest increases biodiversity through habitat provision, so an overall decrease is indicative of a decrease in ecosystem condition. 

Normalised Difference Vegetation Index (NDVI)

Normalised Difference Vegetation Index (NDVI) values for Forest & Woodland remained broadly stable between 2018 and 2024. These results indicate consistent levels of vegetation throughout the period (Figure 2.5, Table 2.7).

Looking at different types of Forest & Woodland, most forest types showed little variation over the reference period. In 2024, Coniferous Forest, Mixed Forest, and Plantations all had NDVI values of 0.79, which was higher than Broadleaved Deciduous Forest, at 0.76, and Transitional Forest & Woodland Shrub, at 0.72. Broadleaved Deciduous Forest is dominated by trees that lose their leaves in the winter and generally has more open canopies, and so it would be expected to have less vegetation across the year when compared with Coniferous Forest, Mixed Forest and Plantations. 

Overall, this condition indicator variable indicates that Forest & Woodland ecosystems have consistent amounts of vegetation throughout the reference period, and are in good condition. Tracking NDVI in the future may be able to contribute to a better understanding of forest health including deforestation events or episodes of disease.

Biotic Ecosystem Characteristics - Functional State

Growing Stock Volume

Growing stock volume for Forest & Woodland increased between 2018 and 2024. The average growing stock volume increased from 154.9 m³ per hectare in 2018 to 188.4 m³ per hectare in 2024. This represents an overall increase of approximately 22% between 2018 and 2024 (Table 2.8).

Growing stock volume in Forest available for wood supply (FAWS) increased from 167.2 m³ per hectare in 2018 to 189.5 m³ per hectare in 2021 and 203.2 m³ per hectare in 2024. Growing stock volume in Forest not available for wood supply (FNAWS) also increased, rising from 111.9 m³ per hectare in 2018 to 127.1 m³ per hectare in 2021 and 136.5 m³ per hectare in 2024.

Overall, the results indicate that the volume of standing timber increased across all categories of forest over the period, consistent with continued forest growth and maturation. A high growing stock volume can indicate that a forest is maturing, and can provide high levels of ecosystem services such as carbon sequestration and storage which are components of the Global Climate Regulation service, or the growth in timber stocks of the Wood Provision service.

Forest Damage

The area affected by disease rose from 230 hectares in 2017 to 470 hectares in 2018, fell to 80 hectares in 2021, then increased substantially to 960 hectares in 2024 and further still to 1,470 hectares in 2025 - the highest disease total recorded across the entire period. Wildfire damage showed a decline from 1,960 hectares in 2017 to 500 hectares in 2018, 100 hectares in 2021, and just 20 hectares in 2024, with no wildfire damage recorded in 2025.

Storm / wind damage stood at 500 hectares in 2017, with no data recorded between 2018 and 2024, before rising to 27,400 hectares in 2025 — the only two data points in the series. This 2025 figure accounts for almost all of the total damage recorded that year and represents by far the largest single disturbance value across the entire reference period (Figure 2.6, Table 2.9).

Landscape and Seascape Characteristics - Landscape and Seascape

Landscape Naturalness

Landscape naturalness is a measure of the proportion of natural and semi-natural or modified and anthropogenic ecosystems in a landscape. It provides information on the degree to which a landscape has been influenced or impacted by human use. For Forest & Woodland, landscape naturalness remained at 26.6% from 2018 and 2021, before increasing by 0.8% to 26.8% in 2024 (Figure 2.7, Table 2.10).

Looking at different types of Forest & Woodland, varying trends are evident. From 2018, no change was seen for Broadleaved Deciduous Forest (27.6%). Mixed Forest and Plantations both saw small increases, while Transitional Forest & Woodland Shrub increased by 6% between 2018 and 2024 to 30.1%. Coniferous Forest saw an overall decrease of 3.4% between 2018 and 2024 to 28.7%.

Overall, these results tell us about the type of landscape within which the Forest & Woodland ecosystems are located. In Ireland, a large proportion of our ecosystems can be considered highly modified or anthropogenic, including Cropland, Sown Pastures & Other Grass, and Plantations themselves, with few ecosystems considered natural or semi-natural.