A passenger flying over Ireland 20,000 years ago would not have recognised what they were looking down upon.

For starters, the sea level was around 120 metres lower than it is today, meaning Ireland was connected to the United Kingdom, which in turn was connected to mainland Europe.

Of course, this would not have been apparent to the viewer, as the entire continent lay beneath a sheet of ice up to a kilometre high in places. It was around this time that the Earth’s climate entered a warming phase.

By 10,000 BC, the majority of western Europe was ice-free all year around.

Seeds from unglaciated areas to the south were carried north and west by wind, rivers, and in the bellies of migrating animals.

They colonised the bare ground left beneath the ice sheets, first with herbs and grasses, then scrub and patchy woodland.

By around 7,000 BC, the cycle of ecological succession had concluded. High-canopy climax woodlands of oak and elm blanketed the fertile soils. Birch and Scots pine dominated the uplands, with alder and willow in the sodden lowlands.

The first humans arrived here at around 6,000 BC. They were Mesolithic (Stone Age) hunter-gatherers.

They maintained this way of life for at least 2,000 years, living under the canopy of the great forest alongside wolves, bears and wild boar.

The arrival of agriculture

The arrival of agriculture marked the beginning of the end for this primordial woodland culture. Mastery of ironworking would arrive a little later and function as a major accelerant of decline.

Our ancestors now had the motivation to clear the forests, and an effective tool to do the job.

British woodland ecologist, Oliver Rackham, suggested tree cover in Ireland was reduced to just 20% by 3,000 BC.

By the time of the Ulster plantations, less than 10% remained, confined to the most remote places, or increasingly within the walls of large estates.

A surging rural population in the 1700s put great pressure on the last fragments of native woodland, and whilst this trend was temporarily reversed in the aftermath of the Great Famine, the overall trajectory remained downward.

In 1881, the first of the Land Acts associated with Home Rule were passed in London. It was now clear that the future of the aristocratic estate was no longer secure.

In the years that followed, Ireland lost around 100,000ha of its remaining woodlands, either liquidated by the former owners on their way out, or cleared by the new owners on their way in.

The Black-faced ewe arrived in the west of Ireland around the same time, quickly displacing the prevailing cow-based system.

The sheep’s hardy nature meant it grazed all parts of the mountain and was left out year-round, giving forests little chance to regenerate.

1% forest cover by 1900

By 1900, Ireland was down to just 1% forest cover. The Irish State was formed in 1921 and, whilst it had aspirations for woodland restoration, little was done beyond trials in the initial decades.

It was not until the ’50s that the Forest Service (now Coillte) began afforestation in a serious way. The model was simple – plant marginal land, grow for 40 years, clear fell, and repeat.

In the mid-90s, the State pulled back from direct planting of land.

Farmers were now to be tasked with delivering our forestry targets. And deliver they did. As we moved into the new millennium, Ireland was putting 20,000ha of land a year into forestry, reaching 10% total land cover.

Trouble ahead

Planting land is no small thing for farmers. There is a permanent land-use change clause in forestry – once you go in, the land cannot be farmed anymore.

It is, in essence, a long-term contract with the State: they pay the establishment costs and cashflow the unproductive early years, and the landowner gets to sell the harvest. A good deal, it would appear.

However, from around 2008, a sequence of unfortunate events would see farmers’ confidence in forestry wane. In the aftermath of the financial crisis, forestry premiums payments to farmers were cut, both in value and duration.

Diseases like ash dieback and phytophthora hit plantations, leading to more financial losses for landowners. Finally, in 2018 a court case relating to forestry’s environmental impact saw the forest licensing system effectively collapse.

With no effective remediation measures and no entitlement to fix matters for themselves, farmers were left swinging. The State had reneged on its side of the deal. Bad news travels fast.

“Don’t get into forestry, you’ll get burned,” was the message being spread.

In 2022, just 2,000ha of new forests were planted. Out of that figure, farmers planted just 400ha. The remainder was planted by non-farmers and investors.

Whilst Ireland’s official forestry programme floundered, its wild woodlands were expanding fast.

Data from Tailte Éireann and the National Forest Inventory (NFI) showed that between 2017 and 2022, tree cover increased by 38,328ha; yet, only 19,819ha of land was planted during this period. The remaining 19,009ha, dominated by pioneer species such as birch and willow, can only be explained by the reproduction of wild trees. Policy changes and rural demographic suggests this trend is only going one way.

As we move into 2024, Ireland’s total tree cover in the form of native woodlands, commercial forestry, emergent woodlands and hedgerows stands at 18.5% of its land area.

The State now relies heavily on forestry to mitigate its total greenhouse gas emissions. To meet its 2035 climate targets, an additional 6% of the countryside will need to be planted.

Teagasc estimates that this will require at least 18,000ha of land to be planted every year between now and then. A tall order, by any measure.

It is hoped that the recently bolstered programme of financial supports for woodland creation can function as a much-needed reset for the ailing sector.

Ray Ó Foghlú is an environmental scientist and woodland conservationist. He is the farm programmes co-ordinator with the Hometree charity. He recently completed a Nuffield scholarship on ‘Acquiring social licence to increase tree cover on the Irish landscape’. In his contributions to the Irish Farmers Journal, he will focus on Ireland’s native woodlands and offer advice to farmers on how to improve these habitats on their farms.