The first impression when walking through Cloragh Forest is the profusion of light. Even though it is a predominantly coniferous forest, shafts of sunlight permeate the canopy, providing a mixed mosaic of dappled colours on the verdant forest floor. This is especially noticeable on a bright May morning as I receive a guided tour of the forest, located outside the village of Ashford, Co Wicklow, with Liam Byrne, chair of Pro Silva Ireland.
The second feeling is permanency. This multistorey forest seems like it has existed for millennia. Majestic Douglas fir and Sitka spruce coexist with older Scots pine, while below the canopy, diverse tree species of varying heights vie for room and light.
Young western hemlock competes with larch, fir, spruce and pine, while individual oak, birch and sweet chestnut bide their time. Cloragh is no ordinary forest. It is managed in accordance with the principles of continuous cover forestry (CCF).
Liam, who manages the forest, acts as silvicultural conductor in directing the individual tree species’ performances while ensuring continuity and permanence, which are the hallmarks of CCF. He allows the Scots pine and oak their own space as solo native performers, while Japanese larch and rapidly regenerating western hemlock provide supporting roles, kept in check to allow the main species – Sitka spruce and Douglas fir – to play the lead roles.
Like any conductor, he is conscious of striking the right notes for his audience – and customers – so the lead parts are consigned to the tree species that generate a steady flow of logs to sawmills and a continuous income stream for the forest owner. “The forest that pays is the forest that stays,” he says.
“The main objective is to produce quality timber. The social and environmental benefits follow,” he adds.
While the forest seems ancient, it isn’t that old at all. The dominant conifer trees – up to 40m tall – along with the middle and rapidly regenerating understorey bear no resemblance to the forest that existed only a few decades ago. “As recently as 2005, there was no regeneration”, says Liam. Browsing deer contributed to the lack of emerging seedlings but “some visitors to the forest questioned if the Irish climate was a factor in preventing natural regeneration”.
Whatever about the deer, climate had nothing to do with the lack of regeneration. It was light, or rather lack of it reaching the forest floor. As soon as this was understood, through his involvement with Pro Silva, trees were selected for removal to allow more light in and regeneration followed. CCF is the opposite to conventional or clear-cut forestry, where smaller trees are removed as thinnings at four-to-five-year intervals to benefit the final crop, which is eventually clearfelled.
In a forest that is being transformed to CCF, thinning is also done on a four-to-five-year cycle. However, the focus is to harvest some of the larger trees and give space for the development of future quality trees. The gaps created by removing the larger trees allow an understorey of young trees to naturally regenerate. This way, the forest renews itself without ever resorting to clearcutting and planting.
CCF makes it is possible to harvest trees and preserve the forest, at one and the same time
Key to success has been the continuity of management across the 197ha at Cloragh. Under the custodianship of Captain Charles Tottenham, much tree planting took place from the 1950s to 1970s, making use of a wide range of species. Liam’s father Larry started working the woods in 1973, which resulted in a shared vision to develop the forest.
Charles passed the forest on to his son, the late Geoffrey Tottenham, and his wife Lucy, who is the current owner. They initiated the CCF programme in 2005 and were encouraged by the forester Paddy Purser, a founder member of Pro Silva, who has acted as forestry consultant in Cloragh since the 1990s.
CCF was a learning experience for Liam. He admits that he was overly conservative initially about removing trees, but has become braver to ensure that sufficient light reaches the forest floor. With growing confidence, he now says that “CCF makes it is possible to harvest trees and preserve the forest, at one and the same time. There is a steady flow of timber income while all the other elements that people love in a natural forest are retained.”
In a well-developed part of the forest, removing some of the poorer-quality trees in early thinnings has paid dividends over the long run. Harvest operations every four to five years now generate a profitable yield of 80m3/ha, of which 90% is quality commercial sawlog. This high-level output belies the argument that CCF is an uneconomic silvicultural system.
Liam acknowledges that the management and cost profile in CCF is different from conventional forestry. For example, marking the trees to be removed is an investment, but the ability of the forest to regenerate without replanting is a saving. Tree removal requires extremely skilled harvest operators who understand the synergies involved in CCF.
Liam credits the whole harvesting team with success, including his brother Paul, Brendan Murphy, Joe Kavanagh, and other colleagues.
At times when walking with Liam, you get the impression he knows each individual tree. We pass a well-formed oak that was allowed to emerge because a massive nearby Sitka spruce was harvested.
While Douglas fir and Sitka are the major species, there are examples of other trees, including birch and mountain ash, being allowed the space to contribute to the forest ecosystem. Liam is conscious of the role these species play in improving diversity and soil amelioration. They add to the beauty of the forest and its value for wildlife. “We are only learning now about how these species interact with each other,” he maintains.
“There are energies happening here that we don’t fully understand, especially in the root system.”
Because so few trees are removed, there is no damage to the soil or other trees, which is a major advantage of CCF. “Foresters have much to learn about CCF, which is why Pro-Silva’s role in education is so important,” he says.
Liam emphasises the importance of Pro Silva in promoting and developing CCF.
“Pro Silva has been the key to providing a greater understanding of CCF, especially through Irish and international field days. Meeting foresters from countries with a CCF tradition has been extremely important in my own development as a CCF forester.”
He praises the organisation, which ensures that sustainability and resilience is at the core of its approach, especially in the following CCF guiding principles:
As Pro Silva chair, Liam is proud of the organisation and its 100 members. Cloragh Forest benefits from CCF. In return, the Tottenham family places the forest at the disposal of Pro Silva for educational field trips by foresters, forest owners and students.
Its attractiveness as a well-managed mature forest is acknowledged by the local film studio, which has featured it in a number of movies.