I recently visited Seán Ó Conláin’s forest to learn about his efforts to work with nature while still making the forest economically viable.

Edergole Forest
Critics often complain that single species plantation forestry, especially conifers, are staid and lifeless areas. However this forest, located in the rolling hills of County Leitrim is wonderful. A towering ancient oak greets you on your approach up the driveway to the house. And behind the house, when you walk through Edergole forest you get a wonderful feeling of being immersed deep in nature. A wide range of plants grow under the canopy of high trees and the birds sing noisily in the background. The original hedgerows and ditches that once separated the original fields are still in situ and are rich with a mosaic of common countryside flora. So how did it get like this?

Becoming a Forest Owner
Seán and his wife Bríd moved from Dublin to their idyllic rural home at Edergole near Dromahair in 2003. Both were newcomers to forestry back then but had a strong appreciation for nature. So in 2004 the decision was taken to plant a mixed broadleaf forest on an area of about 15 acres. Species planted included ash, oak, alder, birch, rowan, sweet chestnut, some Scots pine, spruce, hazel, maple etc. Seán was quite hands on with the establishment of the plantation and had no unusual challenges in establishing the young saplings. There were fewer deer in the area back in 2004 (to nibble on juicy leaves) and so once the trees had taken root they slowly started to stretch year on year.

A New Challenge
In 2013 something happened which Seán and Bríd were not expecting – a 20 acre forest adjoining their land came up for sale. After little interest from other parties, the couple decided to buy this additional plot. It had been planted in 1987 and was towering at around 16 meters high. The plot was entirely Sitka Spruce and Seán began researching how best it could be managed. Seán was sure that clearfelling the forest in one sudden action wasn’t what he wanted. Instead he researched management options that would take a more sensitive and gradual approach. He began reading about a practice called “continuous cover forestry” or CCF for short, which was beginning to take hold in the UK and which had been common on the continent for decades. CCF is sometimes also known as Close to Nature forestry and involves avoiding clearfell by slowly removing timber in gradual amounts. In addition to gradual and selective harvesting operations, CCF aims to create the conditions in the forest which ensure the trees remain resistant to blowing over. CCF also encourages natural regrowth of self seeded trees to minimise manual planting. Trees always remain standing on a CCF site so the risk of disturbed soil running into waterways (during harvesting) is reduced. Indeed nature as a whole is allowed to express itself over time without the familiar and unnatural rows of trees that are common in plantations. But there was a problem with Seán’s vision.

Risk of Windblow
The previous owners of the Sitka forest had carried out no thinning operations. Seán learned that thinning for the first time at such a late age (26 years since planting) would hugely increase the risk of windblow. Some practitioners of CCF are recommending a first thin when the plantation is as young as 13 to 15 years old – this allows the root plate of the small trees to stretch out wider which keeps them grounded in their later years. Undeterred, Seán engaged Paddy Purser, a forester with experience of continuous cover forestry operations and in 2014 they established research plots in three places in the Sitka plantation. This created a record of details such as 1) Number of trees per plot and thus an indicative average for the forest as a whole. 2) Details of tree width and height 3) Form of the trees – their shape and structure and 4) Other observations such as soil condition, roadway access, drainage etc. Paddy made it clear to Seán that the combination of age, height and soil type as well as the likelihood of strong winds made late thinning a risky enterprise with no guarantees of success.

The Worst that Could Happen
Seán weighed up the risks and concluded that windblown timber could still be salvaged so in this sense not all would be lost if he thinned, and thus the process of transformation to CCF started. Granted, it would be better to be salvaging trees that were older but the late thinning wouldn’t jeopardize the investment entirely. So in 2014 a roadway to the upper section of the conifer plantation was completed and the first thinning commenced in 2015. Harvesting machinery is very heavy and can dig or “rut” deeply into the soil, breaking roots and increasing chance of windblow. So in response the decision was made to bring in men to carry out this initial harvesting using hand operated chainsaws. This would test the waters for future thinning operations. A small mechanical “forwarder” was used to collect the sawn timber. In total 1080 trees were cut with a combined weight of 380 tons. 135 tons of this was saw log; 85 tons pallet wood and 158 tons pulp. Saw log followed by pallet wood are the most valuable timber in the forest and CCF often removes slightly more of this higher value timber in the initial thinning operations. Traditional first thinning (where clearfell is the ultimate objective) concentrates on removing the weakest, smallest trees. The first thin in any forest typically involves the removal of one complete row of trees in seven to create an access rack or alley. Future forestry operations generally stick to this pathway to concentrate soil disturbance in one section as opposed to across the entire site. A few other trees from either side of the rack were also selectively removed.

Strong Storms
Several strong storms followed in the months following the operations but thankfully there was minimal wind blow. Seán and Bríd were delighted that the operations had been a resounding success. Seán also used the principles of continuous cover approach in the broadleaf forest. It was thinned by chainsaw and the best broadleaf trees were marked to allow to grow on to full maturity. Buoyed on by how wind resilient the initial conifer thinning had proven, Seán began making plans for a second conifer harvesting operation. The forest road was extended in 2017 to the a lower section of the conifer forest which hadn’t been harvested and thinning began in 2018. The original section had its second thinning which removed 300 trees while the lower conifer section got it’s first thinning, removing 700 trees. This time the team decided to use a mechanical harvesting machine and it worked well with little soil damage. Details of timber removed was 86 tons of saw log; 115 tons pallet wood and 291 tons pulp so a total of 493 tons. Paddy and Seán decided to under plant 150 trees (such as hornbeam, hazel and beech) under the towering conifers – this planting is technically referred to as enrichment planting. This would kick start the regeneration of the next generation of the forest and also be an interesting test of how light levels were favoring the growth of new trees. Seán was happy to do this planting work himself which kept costs to an absolute minimum. Also the sample research plots first measured in 2014 have been revisited several times since establishment and this is helping to guide exact volumes to be removed at thinnings.

Ash Die Back and Windblow
2019 brought a mixed bag. Unfortunately Seán noticed that his forest had Ash Dieback (Chalera). The decision was made to allow the affected ash trees to put on more girth. Seán and Paddy are continuing to monitor the spread of the disease closely. Further thinning was carried out in the broadleaf area and drainage was improved to the Sitka plantation. Wet soil encourages wind blow so allowing the ground to dry quicker would be of long term benefit. In 2020 further enrichment planting was carried out on the spruce plantation with 250 of both beech and Western Red Cedar planted. In 2021 a further thinning was carried out yielding 494 tons. This contained 190 tons of saw log. 140 tons of pallet wood and 164 tons of pulp. A further 178 tons of deadwood pulp was also removed. Ground conditions were wet and unfortunately deep rutting occurred during the operations. And in the recent storms in spring of this year, 2022, windblow occurred on the highest part of the forest. Earlier this year more enrichment planting was carried out on the upper conifer section with: 250 cedar, 500 beech and 200 hazel planted with about 10% planted in the broadleaf section. Finally a further thinning of other broadleaf trees was carried out by hand in March 2022.

So Where Next?
As regards the windblow Seán is considering his options. Seán has no regrets about choosing continuous cover but it’s very much a “wait and see” approach to the conifer area. To this end he is exploring lighter forwarding equipment and extending his forest road to reduce rutting and impact caused by the fowarder travelling with heavy loads across long distances. The area of windblown damage isn’t so large or severe to justify bringing in machinery to salvage the timber. Equally, if the area of windblow spreads in future storms Seán may have to consider a partial or complete clearfell. His efforts in the conifer area won’t have been in vain regardless of the outcome. He has already started planting and encouraging the growth of the next generation of trees to replace those standing. And in the years since the first thinnings, light has streamed down onto the forest floor encouraging a wide variety of native plants to naturally regenerate. With plants come insects and larger mammals encouraging a wonderful web of life. This wouldn’t have been achieved without that risky initial thinning. For other forest owners then, Seán’s advice would be to thin early to encourage wind firmness and where possible, to move the plantation in the direction of “continuous cover”.Seán also mentioned his appreciation of the support he has received from the Forestry Service on his forestry journey.

For more articles on managing forests using continuous cover forestry, visit www.prosilvaireland.com